WINTER USE PLANS

FINAL ENVIRONMENTAL IMPACT STATEMENT

VOLUME I

for the

Yellowstone and

Grand Teton National Parks

and

John D. Rockefeller, Jr.,

Memorial Parkway

U.S. Department of Interior

National Park Service
Winter Use Plans

Final Environmental Impact Statement

Volume I

 for the

Yellowstone and

Grand Teton National Parks

and

John D. Rockefeller, Jr.,

Memorial Parkway

Prepared by the U.S. Department of Interior, National Park Service in cooperation with the U.S. Forest Service; the

States of Idaho, Montana, and Wyoming; and the Counties of Gallatin and Park, Montana, Park and Teton, Wyoming,

and Fremont, Idaho.

This document presents and analyzes seven alternatives for winter use management in Yellowstone National Park

(YNP), Grand Teton National Park (GTNP), and the John D. Rockefeller, Jr., Memorial Parkway (the Parkway). YNP,

encompassing 2.22 million acres, and GTNP, comprising 310,000 acres, form the core of the Greater Yellowstone

Ecosystem, described as the last large, nearly intact ecosystem in the northern temperate zone. The approved plan will

serve as a management plan for the three national parks.

Alternative G, the preferred alternative, emphasizes clean, quiet access to the parks using the technologies available

today. It would allow over-snow access on all routes currently available via NPS-managed snowcoach only. Other key

changes in recreation opportunities are: eliminating winter plowing on the Colter Bay to Flagg Ranch route, making

Flagg Ranch a destination via over-snow transport, and eliminating all winter motorized use on Jackson Lake. This

alternative addresses the full range of issues regarding safety, natural resource impacts, visitor experience and access. It

addresses the issues in a way that would make it necessary for local economies to adapt, and for snowmobile users to

access the parks using a different mode of transport. Under alternative A-No Action, current use and management

practices in the parks and Parkway continue. The concept under alternative B provides a moderate range of affordable

and appropriate winter visitor experiences. Air quality and oversnow motor vehicle sound would be addressed, and by

the winter of 2008-2009, strict emission and sound requirements would be required by all oversnow vehicles entering

the parks. This alternative also emphasizes an adaptive approach to park resource management, which would allow the

results of new and ongoing research and monitoring to be incorporated. Alternative C maximizes winter visitor

opportunities for a range of park experiences. Alternative D stresses visitor access to unique winter features in the

parks. This alternative emphasizes clean, quiet modes of travel, visitor activities focused near destination areas, and a

minimization of conflicts between nonmotorized and motorized users. Under alternative E the protection of wildlife

and natural resources is emphasized while allowing park visitors access to a range of winter recreation experiences.

Alternative E uses an adaptive planning approach that allows new information to be incorporated over time. Alternative

F stresses the protection of wildlife resources by focusing winter visitor activities in YNP outside important winter

range for large ungulate species, and closing north and west roads to winter use. For GTNP and the Parkway, this

alternative emphasizes the protection of all resources by focusing developments, oversnow motorized trails and zones,

and nonmotorized trails and zones in certain areas, while still allowing park visitors opportunities for a range of winter

recreational experiences.

The details and impacts of the alternatives are described in this document. They include major long-term beneficial

improvements to the protection of geothermal winter range and other park resources, some adverse effects from visitor

use activities, and major beneficial improvements to the desired visitor experience for solitude, clean air, and natural

quiet. These impacts vary by alternative.

For more information about this document, contact Clifford Hawkes, 12795 West Alameda Parkway, Lakewood,

Colorado 80228. The NPS is requesting comments on the plans/FEIS, although it is not legally required to do so. All

comments must be received by October 20, 2000 and should be sent to the above address or the email address:

yell_winter_use@nps.gov. Comments received after this date will not be considered. Comments transmitted by

facsimile machine will not be considered. To meet a deadline in a court-approved settlement agreement for this

plans/EIS, the NPS cannot extend the comment period. A full copy of this document is available on the Internet at the

National Park Service web site www.nps.gov/planning. Copies are also available at local libraries. Written requests for

full copies of the document should be directed to Clifford Hawkes at the address above. Please specify whether you

wish a paper copy or a copy on CD ROM.
ii
iii

SUMMARY

INTRODUCTION

In 1990, a Winter Use Plan was completed for Yellowstone National Park (YNP), Grand Teton

National Park (GTNP), and the John D. Rockefeller, Jr., Memorial Parkway (the Parkway). In

1994 the National Park Service (NPS) and U.S. Forest Service began work on a coordinated

interagency report on Winter Visitor Use Management. This effort was in reaction to an earlier

than expected increase in winter use. The 1990 Winter Use Plan projected 143,000 visitors for

the year 2000. In 1992-93 winter use in YNP and GTNP exceeded this estimate.

In 1994, the Greater Yellowstone Coordinating Committee (GYCC), composed of National Park

Superintendents and National Forest Supervisors within the GYA, recognized the trend toward

increasing winter use and identified concerns related to that use. The GYCC chartered an

interagency study team to collect information relative to these concerns and perform an analysis

of winter use in the GYA. The analysis, Winter Visitor Use Management: a Multi-agency

Assessment was drafted in 1997 and approved by GYCC for final publication in 1999. The

assessment identified desired conditions for the GYA, present areas of conflict, issues and

concerns, and possible ways of addressing them. The final document considered and

incorporated many comments from the general public, interest groups, and local and state

governments surrounding public lands in the GYA.

In May of 1997, The Fund for Animals, Biodiversity Legal Foundation, Predator Project,

Ecology Center, and five individuals filed suit in the U.S. District Court for the District of

Columbia alleging failures by the NPS to comply with the National Environmental Policy Act

(NEPA), the Endangered Species Act (ESA), and other federal laws and regulations in

connection with winter use in the three national parks. The NPS subsequently settled the suit, in

part, by an agreement to prepare a comprehensive environmental impact statement (EIS)

addressing a full range of alternatives for all types of winter use in the parks. This is the final

environmental impact statement (FEIS) that fulfills that portion of the agreement.

The NPS has prepared this FEIS on its preferred alternative, no action alternative, and five

additional alternatives. This Summary outlines the FEIS.
SUMMARY

iv

BACKGROUND

Regional Setting

The GYA encompasses over 11 million acres and is considered one of the few remaining intact

temperate ecosystems on earth. Within the area, YNP comprises 2.22 million acres, primarily in

northwestern Wyoming and extending into south central Montana and eastern Idaho. GTNP

encompass an additional 310,000 acres and the Parkway includes 24,000 acres both located in

Wyoming. YNP and GTNP comprise the strategic core of an upland plateau called the GYA.

Portions of six national forests — Gallatin, Custer, Shoshone, Bridger-Teton, Caribou-Targhee,

and the Beaverhead-Deerlodge are within the GYA, as are the National Elk Refuge and Red

Rocks National Wildlife Refuge. Public lands make up most of the area (69%). Private lands

comprise 24% of the GYA, Indian reservations comprise 4%, and 3% of the lands in the GYA are

state lands. The GYA extends across 17 counties in 3 states. Cooperative agreements and

interagency planning and coordination aid in managing the area as an ecological unit, while

recognizing the different mandates of the land management agencies.

With the national growth in winter activities such as snowmobiling and ski touring, winter visits

to the 3 parks have increased from virtually none 30 years ago to more than 100,000 per year by

1980. The parks’ winter activities have become an important part of the region’s tourism

industry. Increased winter use has raised concerns about impacts on park resources and values,

and placed significant demands on the parks’ facilities, equipment, and personnel. These

demands also affect adjacent national forests and local communities. Until recently when

increased and new uses appeared, they were addressed according to established NPS policies with

little additional funding or personnel. It is now apparent that winter activities are an integral part

of the visitor experience in the GYA, and that more specific policies and management direction

are needed to guide winter use in the parks and protect sensitive resources.

The outcome of this EIS is the development of a plan for each park addressing existing and

potential impacts on resources and values from winter recreational uses. A plan of this sort,

termed “programmatic,” is general in nature. It is aimed at describing a program for winter use

by stating objectives and goals and determining the types of uses that are consistent with those

goals. It describes the conditions under which certain activities are acceptable and provides

general standards for management. It also provides an overall allocation of lands where certain

activities are or are not consistent with objectives.

An EIS is necessary to evaluate alternative choices for plans while revealing the possible

environmental impacts of activities that may be included in the plans. Because a plan of this type

is general in nature, an analysis of environmental impacts need only be conducted at a general

level. The type and amount of data relating to possible impacts is presented at the general level

and is not exhaustively detailed and “site-specific.” Detailed and site-specific data would be

required of analysis for a specific activity, such as the construction of a single facility.

The purpose of and need for action in an EIS is a brief statement specifying the underlying

purpose and need to which the agency is responding in proposing the alternatives, including the

proposed action. The need to develop a plan through an EIS is indicated by the difference
PURPOSE AND NEED FOR ACTION

v

between overall desired condition and the conditions that presently exist. The desired condition

reflects the parks’ mandates, and is articulated below as a series of general objectives.

Documentation of the existing condition is based on parks’ monitoring, levels of present winter

recreational use, and other information available through the winter visitor use assessment

(GYCC 1999). Existing conditions reflect management and public concern about impacts on

resources and visitor experiences that conflict with the stated objectives. The final plan will be

designed to move the existing condition toward the desired condition.

PURPOSE AND NEED FOR ACTION

Desired Condition

Proceeding from the NPS mandates, which include legislation, regulations, executive orders, and

governing policies, the following statements summarize the desired condition of the three parks

for winter use. These bulleted statements may be viewed as objectives for a new winter use plan:

• Visitors have a range of appropriate winter recreation opportunities from primitive to developed.

Winter recreation complements the unique characteristics of each landscape within the ecosystem.

• Recreational experiences are offered in an appropriate setting; they do not take place where they

will irreparably impact air quality, wildlife, cultural areas, the experiences of other parks’ visitors, or

other parks’ values and resources.

• High quality facilities are provided in parks to support the need for safety and enhanced visitor

experiences.

• Conflicts among user groups are minimal.

• Visitors know how to participate safely in winter use activities without damaging resources.

• Oversnow vehicle sound and emission levels are reduced to protect employee and public health and

safety, enhance visitor experience, and protect natural resources.

Existing Condition

Despite interagency cooperative efforts, including working with other federal and state agencies,

counties, communities, and a variety of interest groups, many unresolved issues and concerns

exist about winter use in the three parks. Land managers, constituencies, and users of public

lands disagree about the appropriateness of certain uses, the amount of various uses being

provided, and the effects of those uses. These unresolved issues and concerns contrast with the

desired condition expressed above, and represent the need for a new plan.

• Visitor Access: Access to most locations is limited to those who can afford to ride a snowcoach or

snowmobile. Access for personal motorized use via snowmobile has increased greatly since the

beginnings of the winter program in the three parks. Snowmobile use, in current numbers, is in

conflict with use of parks’ facilities by other user groups.

• Visitor Experience: A variety of winter use conflicts has been identified involving the relationship

between users and among different user groups, which affects how people experience the parks. At

destination facilities and trails open to both motorized and nonmotorized users, nonmotorized users

express dissatisfaction with the sound, odor, and quantity of snowmobiles. These vehicles affect the

solitude, quiet, and clean air and other resource values that many people expect and wish to enjoy in

national parks.

• Visitor Safety: The current level of snowmobile accidents, unsafe users, inherent winter risks, and

conflicts between users are of concern from the standpoint of public safety.

• Resources: Parks have documented health hazards from snowmachine emissions, harassment and

unintended impacts on wildlife from groomed trails and their use, degradation of air quality-related
SUMMARY

vi

values, and impacts on the natural soundscape. Many people strongly object to the degradation of

inherent parks’ values, as well as how these impacts affect people and their recreational

opportunities.

Scope of Analysis — Range of Alternatives Considered

The scope of analysis determines the range of alternatives to be considered. The analysis in this

EIS is limited to recreation during the wintertime (about December 15 through March 15,

annually).

Geographically, the analysis is limited to recreation management within the boundaries of the

three national park units.1 Recreational use considerations and supporting facilities are limited to

those that are technically possible at the present time or are feasible for development and

implementation.

The range of alternatives presents options for motorized and nonmotorized winter recreational

use in the three park units considering reasonably expected technological improvements in

emissions and sound of snowmachines. One alternative must evaluate the impacts of current

winter use (per the settlement agreement and CEQ regulations). In this instance, “no action” is

interpreted as current management, which is appropriate for programmatic planning.2

The scope of this EIS, in terms of the decision to be made, is the winter recreation program. Any

winter use may overlap or potentially affect other parks’ management concerns. These include

wildlife management (particularly bison), concession facilities and their management, and

transportation infrastructure. To the extent possible, the impact analysis considers ramifications

on other management issues. However, it is not possible in this EIS to evaluate the entire

concession program, wildlife program (including animal carrying capacities), or transportation

system.

For example, existing facilities for fuel storage and solid waste storage and handling in YNP are

inadequate for current winter use levels. Wastewater treatment facilities in YNP are insufficient

at current winter and summer use levels. It is not within the scope of this analysis to consider

alternatives for improving basic infrastructure needs to increase capacity. This is not feasible in

the present fiscal climate, and given current use levels and their impacts on resources. In addition

separate analyses are proceeding to bring some of the aging infrastructure into compliance. The

scope of this analysis is a programmatic assessment of facilities that are intrinsic to winter

recreation experiences and opportunities, such as trails and warming huts.

 

1

 As a matter of process under CEQ regulations, the impacts of park management that are known or suspected to occur

at other times and places must be disclosed in the EIS. In this EIS, economic impacts outside park boundaries are

disclosed in the socioeconomic impacts section. Physical and resource effects are disclosed in the sections on adjacent

lands and cumulative impacts.

2

 Many commenters on the DEIS stated that NPS must have a “no action” alternative — meaning no snowmobiling —

to have a full range of alternatives, and that the court settlement showed that to be the appropriate course of action. The

park service’s interpretation of “no action” means no change in general management direction from the present. The

settlement agreement did not include any concessions to claims by The Fund for Animals, nor did it remove any

options within the park service’s discretion for park management from the range of alternatives to be considered. In

approving the settlement agreement, the court asserted that a comprehensive winter use EIS (in accordance with CEQ

regulations) would be written.
COOPERATING AGENCIES

vii

COOPERATING AGENCIES

The NPS has been joined in this FEIS by nine cooperating agencies: the U.S. Forest Service; the

States of Idaho, Montana, and Wyoming; and the Counties of Gallatin and Park, Montana, Park

and Teton, Wyoming, and Fremont, Idaho

STATES AND COUNTIES WHERE THE PROPOSED ACTION IS LOCATED

Idaho: Fremont County

Montana: Gallatin and Park Counties

Wyoming: Park and Teton Counties

PUBLIC INVOLVEMENT BEFORE THE RELEASE OF THE DRAFT PLAN AND

EIS

Public scoping comments on the Draft Winter Use Plans/EIS for YNP, GTNP, and the Parkway

were accepted from April 14, 1998 to July 18, 1998. Scoping brochures were mailed to about

6,000 interested parties, and 12 public meetings were held throughout the GYA and in Idaho,

Montana, and Wyoming. In addition to local and regional meetings, four national meetings were

held in Salt Lake City, Denver, Minneapolis, and Washington D.C. About 1,998 comment letters

were received (about 1200 of these were form letters), from which about 15,000 discrete

comments were obtained. Scoping respondents include: businesses; private and non-profit

organizations; local, state and federal agencies; and the public at large. Comments were received

from 46 states and several foreign countries.

NPS determined from the comments seven major issues to be evaluated by alternatives in the

DEIS:

• Visitor use and access

• Visitor experience

• Air quality

• Snowmobile sound

• Human health and safety

• Social and economic impacts

• Natural resources
SUMMARY

viii

PUBLIC INVOLVEMENT AFTER THE RELEASE OF THE DRAFT PLAN AND EIS

The Draft Winter Use Plans/EIS was released to the public in July 1999 for a 90-day review

period scheduled to end November 30, 1999. This review period was extended until December

15, 1999. Public hearings were held in October 1999 in Idaho Falls, Idaho; Jackson and Cody,

Wyoming; West Yellowstone and Livingston, Montana; and Lakewood, Colorado.

By the end of the comment period, NPS had received about 46,500 documents commenting on

the Draft Winter Use Plans/EIS – 6,300 unique documents and 40,200 form documents. Each

document was numbered, and comment information recorded. This system helped NPS

personnel analyze the comments and compose the responses. See Volume III for comments and

responses to the DEIS.

Many commenters expressed consternation about the lack of a “no snowmobiling” alternative in

the DEIS, and suggested that impact descriptions and data to support the EIS and the preferred

alternative were not detailed enough. In some cases the NPS has added information to support

the analysis of impacts in this FEIS. Additionally, NPS is engaged in programmatic planning,

rather than project-specific planning; therefore analysis and data collection have been conducted

on a reconnaissance level. Further, where data is lacking or unavailable even at that level, CEQ

regulations provide for the decision process to continue based on best available data and

professional application of credible methods.

Many people stated they could not support any of the DEIS alternative “mixes.” An inordinate

amount of criticism was levied on the preferred alternative — to the point that constructive

comments on the other alternatives were greatly lacking. Three additional “alternatives” were

proposed: Revised Alternative E (in various forms provided by cooperating agencies and the Blue

Ribbon Coalition), the Citizens’ Solution (provided by a consortium of conservation groups), and

the Natural Regulation Alternative (provided by The Fund for Animals).3 All such comments

were read as the decisions that people would like to see the NPS make, based upon their opinions

about impacts and their interpretations about laws.

The body of comment included little substantive information beyond that disclosed in the DEIS,

and did not demonstrate that an alternative (or an alternative feature) did not belong in the range

of choices available for the decision maker. Given the ability of a decision maker to mix features

from the FEIS range of alternatives, much of the criticism in the public comment does not apply

to the analysis. Regarding the great amount of comment on the preferred alternative, and

perceived lack of justification for it, the NPS responds by saying that such criticism is more

appropriately applied to the decision when it is made. In fact, the NPS changed the preferred

alternative between draft and final EIS whereupon most of these comments no longer apply.

 

3

 Features of Revised Alternative E and The Citizens’ Solution were covered within the DEIS range of alternatives.

Certain features were either considered to be implementation details or outside the scope of analysis. The Natural

Regulation Alternative, by advocating no motorized access or groomed routes, was considered outside the scope of

analysis — although some alternatives close sections of the parks to motorized use, and adaptive management could

conceivably result in other sections being closed over time.
ALTERNATIVES

ix

Some commenters said that the desired conditions or objectives were too general, and that there is

no demonstrated need for management change. In effect, such comments missed the real issues

that are conveyed by statements of existing conditions. The NPS responds by explaining that this

is a programmatic EIS leading to a plan, which is general in nature. In addition issues regarding

resource impacts, health and safety, and visitor experience are documented sufficiently by the

NPS to indicate the need for major management changes supported by a new plan.

Given the scope of analysis, the NPS developed alternatives (alternative plans) as possible ways

to proceed from the current condition toward the desired condition. The NPS maintains that

public access during the winter is an appropriate objective to be achieved. Accommodating a

variety of recreational uses is also valid. In each case, activities must be evaluated in terms of

impacts on parks’ resources and values, health and safety, and visitor enjoyment. Alternatives

that vary the location, amount and proximity of uses are needed to assess the relative impact or

change from the current condition. The EIS expresses impacts or changes in terms that allow

people to understand how each alternative satisfies the purpose and need for action. It is

unreasonable to expect that all alternatives would address all aspects of the purpose and need

equally, or that all alternatives worthy of consideration would have no impacts. In the final

analysis, the NPS concludes that the purpose and need for action articulated in the EIS is

appropriate, and that the range of alternatives considered in detail is adequate.

It is the responsibility of the NPS decision maker, in this case, the Rocky Mountain Regional

Director, to weigh the environmental impacts and benefits of all alternatives (and alternative

features) considered in detail in this FEIS against the parks’ mandates. The decision maker must

consider any other factors that may weigh in the decision, including social and economic

considerations and public comments, and make a determination about the best way to meet the

need for action. The determination and its rationale must be fully explained in a record of

decision. There is no actionable or legal decision made until that time.

ALTERNATIVES

Formulation of Alternatives

The alternatives for the Winter Use Plans and Environmental Impact Statement for Yellowstone

National Park (YNP), Grand Teton National Park (GTNP) and the John D. Rockefeller, Jr.,

Memorial Parkway (the Parkway) were formulated in response to the major issues and concerns

raised through public and internal scoping. In addition to the scoping process, the National Park

Service (NPS) and the cooperating agencies met in Idaho Falls, Idaho in October 1998 to

formulate initial concepts for alternatives. Twenty-five participants and about 10 observers

attended the 3-day workshop. Later, similar workshops were held with park staffs in both parks.

In total, over 35 alternative concepts were generated from the 3 workshops. For a complete

discussion of the concepts generated during the workshops see Appendix A.

The NPS planning team evaluated the concepts in terms of their responsiveness to the major

issues and concerns, the decision to be made, and the purpose and need for the Winter Use Plans.

The concepts were also evaluated against their adherence to current law, park management

guidelines, and NPS mandates and policies. Lastly, each concept was evaluated for its economic
SUMMARY

x

and technical feasibility. The concepts that best met the above criteria were packaged into the

range of alternatives discussed below. Each alternative proposed considers a different means of

achieving the desired condition of the parks in the winter while minimizing impacts to park

resources.

Alternative A - No Action

This alternative reflects current use and management practices in the parks and meets the

requirement for including a no action alternative in an EIS.4 Alternative A is a baseline for

analysis and reflects existing conditions. Other alternatives are intended to improve the existing

condition in one or more major issue areas. Issues associated with alternative A include visitor

access difficulties, visitor experience conflicts, unsafe conditions, and resource impacts.

Alternative B

This alternative provides a moderate range of affordable and appropriate winter visitor

experiences. Key changes in recreational opportunities include: plowing the road from West

Yellowstone to Old Faithful to allow mass transit access by wheeled vehicles, moving the CDST

to a year-round path from Moran to Flagg Ranch, and phasing out snowmobile use on Jackson

Lake.

Over the next 10 years, an advisory committee would make recommendations on phasing and

implementing sound and emission standards for air quality and motor vehicle sound issues. By

winter 2008−2009, strict emission and sound requirements would be required by all vehicles

entering the parks. In addition this alternative emphasizes an adaptive approach to park resource

management, which would allow the results of new and ongoing research and monitoring to be

incorporated as it becomes available. Adaptive management increases the Park Service’s ability

to solve visitor access and experience issues and resource issues over time. Using the criteria

stated within Executive Order (EO) 11644 (as amended) and its implementing regulation (36

CFR 2.18), monitoring results demonstrating disturbance to wildlife or damage to park resources

would be cause to implement actions for mitigating these conditions (for example, closure to

winter visitor use or trail restrictions).

Alternative C

This alternative provides maximum winter visitor opportunities for a range of park experiences,

with emphasis on motorized recreation, while mitigating some natural resource impacts and

safety concerns. Key changes in recreational opportunities include: plowing the road from West

Yellowstone to Old Faithful to allow access by wheeled vehicles, providing a widened highway

corridor to accommodate the CDST, and providing additional groomed trails for both motorized

and nonmotorized uses.

 

4

 CEQ 40 Most Asked Questions, question number 3. Where an existing program is being evaluated, “no action” is “no

change in management.” “No action” may be thought of as continuing with the present course of action until the action

is changed. CEQ states that in such instances, “to construct an alternative based on no management at all would be a

useless academic exercise.”
ALTERNATIVES

xi

This alternative directly addresses issues that arose during scoping about potential impacts of

management change on local economies. It shows how the range of winter opportunities could

be preserved, applying mitigation primarily in the areas of air quality and sound impacts.

Alternative D

This alternative emphasizes opportunities for visitor access to the unique winter aspects of the

parks (for example, geysers, geothermal areas, wildlife, and scenic vistas), and protection of those

qualities and natural resources by phasing in clean and quiet modes of travel. It focuses winter

visitor activities near destination areas and gateway communities. Key changes in recreational

opportunities include: eliminating motorized oversnow access to Yellowstone through its East

Entrance, limiting snowmobile use in Grand Teton and the Parkway to the CDST and the Grassy

Lake Road, eliminating wheeled-vehicle access from Colter Bay to Flagg Ranch to accommodate

oversnow vehicles on the groomed highway surface, and eliminating snowmobile use on Jackson

Lake.

Emphasizing uses in different areas of the park minimizes conflicts between nonmotorized and

motorized users, and addresses issues about visitor access and experience. Support facilities

would have minimal amenities. In this alternative, visitor access routes and timing would be

modified to provide safer conditions. Over time, issues regarding impacts on natural resources

would be addressed, particularly in Grant Teton and on the east side of Yellowstone.

Alternative E

This alternative emphasizes the protection of wildlife and other natural resources while allowing

park visitors access to a range of winter recreation experiences. It uses an adaptive planning

approach that allows the results of new and ongoing research and monitoring to be incorporated.

Key changes to current recreational opportunities are: eliminating motorized oversnow access in

Grand Teton and the Parkway except for use on the Grassy Lake Road and north of Flagg Ranch

into Yellowstone, and eliminating all winter motorized use on Jackson Lake.

This alternative addresses the full range of winter use issues in Yellowstone over time, but the

current condition would prevail in the short term. Using the criteria stated in EO 11644 (as

amended) and its implementing regulation (36 CFR 2.18), monitoring results demonstrating

disturbance to wildlife or damage to park resources would be cause to implement actions for

mitigating these conditions (for example, closure to snowmobile use). Alternative E calls for

instituting an advisory committee to make recommendations about emission and sound standards.

Local, county, state, and federal agencies as well as representatives from the snowmobile industry

and environmental groups would participate on this committee. In Grand Teton and the Parkway,

the full range of issues are addressed more immediately by limiting oversnow motorized use to

the north end of the park, thus separating uses and eliminating most resource and visitor

experience conflicts relating to snowmobile use.

Alternative F

Alternative F emphasizes wildlife protection. Key changes in recreational opportunities include:

eliminating all winter access to Yellowstone’s interior through its North and West Entrances,
SUMMARY

xii

eliminating motorized oversnow access in Grand Teton and the Parkway except for use on the

Grassy Lake Road and north of Flagg Ranch into Yellowstone, and eliminating all winter

motorized use on Jackson Lake.

For YNP this alternative addresses issues regarding protection of wildlife resources by focusing

winter visitor activities near scenic areas in the eastern and southern portions of YNP. These

areas are generally outside important winter range for large ungulate wildlife species. In Grand

Teton and the Parkway, the full range of issues is addressed by limiting oversnow motorized use

to the north end of the park, thus separating uses and eliminating most resource and visitor

experience conflicts relating to snowmobile use.

Alternative G - Preferred Alternative

This alternative emphasizes clean, quiet access to the parks using the technologies available

today. It would allow oversnow access on all routes currently available via NPS-managed

snowcoach only. Other key changes in recreational opportunities include: eliminating winter

plowing on the Colter Bay to Flagg Ranch route, making Flagg Ranch a destination via oversnow

transport, and eliminating all winter motorized use on Jackson Lake.

This alternative addresses the full range of issues regarding safety, natural resource impacts, and

visitor experience and access. It addresses the issues in a way that would make it necessary for

local economies to adapt, and for snowmobile users to access the parks using a different mode of

transport.

MITIGATION

Alternatives analyzed in this EIS would produce environmental effects, both beneficial and

adverse. These are disclosed in Chapter IV. For adverse impacts, additional actions are

suggested for the purpose of lessening the magnitude, duration, or intensity of the impact. These

actions, termed mitigation (defined in 40 CFR §1508.20), are recommended as choices for the

decision maker not already included in the alternative.5 A key mitigation feature for most

alternatives is the limitation on snowmobile use in the interim until recreation carrying capacities

can be set.

IMPACTS

Table S-1 summarizes the seven alternatives. Table S-2 outlines potential impacts. The FEIS

provides detailed explanations of the impacts, descriptions of the methods of impact analysis, and

supporting references.

 

5

 Many people who commented on the Draft Environmental Impact Statement (DEIS) suggested alternative features or

different mixes of alternative features. Some suggestions were appropriate as mitigation for certain types of impacts.

Most such suggestions flow logically from the determination of potential impacts disclosed in this EIS. The EPA

suggested that limitations on vehicle numbers would be necessary as an approach to addressing air quality impacts

because the benefits of alternative technologies would not necessarily offset the impacts of increasing numbers. Some

cooperating agencies suggested it would be reasonable to limit numbers as an interim measure until a recreation

carrying capacity could be set. Other suggested measures include establishing rationing or reservation systems, permits

on a first-come, first-served basis, or other means to limit daily and annual use. If a measure or measures were selected

they would become part of the ROD (see Decision to be Made in Chapter I).
S-1. Summary of Alternatives

ALTERNATIVE A

No Action

ALTERNATIVE B ALTERNATIVE C ALTERNATIVE D ALTERNATIVE E ALTERNATIVE F ALTERNATIVE G

Preferred Alternative

Visitor Use & Access

Yellowstone

• Maintain current 180 miles of groomed

oversnow motorized road

• Maintain current 37 miles of groomed

nonmotorized

• Maintain 76 miles of plowed road (include

Hwy 191 to Cooke City)

• Existing winter season from mid December

to mid March

GT/JDRMP

• 100 miles plowed road

• 33.9 miles groomed motorized trail

• 35.6 ungroomed motorized trail or area

• 26.4 ungroomed non- motorized trail or area

All Units

• Increase interpretive opportunities

Yellowstone

• Establish 6 miles of new oversnow motorized trails

• Establish 10 miles of new nonmotorized trails

• Allow all-wheeled public shuttle vehicle access by plowing the road

from West Yellowstone, MT to Old Faithful

• Lengthen season by two weeks from the West Entrance

• Increase size and number of warming huts and other day-use

facilities

• Continue scientific studies in re: impacts of winter visitor use and

park resources; close selected areas or road segments if no other

possible mitigation method

GT/JDRMP

• Establish 6.5 miles of new nonmotorized trail

• Continue current & add destination facilities

• Provide interpretive ski tours

• 5-year phase-out of snowmobiles on Jackson Lake

Yellowstone

• Establish winter campsites (e.g. Old Faithful

area)

• Establish 10 miles of new oversnow motorized

trails

• Establish 20 miles of new nonmotorized trails

• Allow all-wheeled private and public shuttle

vehicle access from West Yellowstone, MT to

Old Faithful

• Lengthen season by two weeks in December

from West Yellowstone to Old Faithful and two

weeks in March from the South Entrance to

West Thumb

• Plow the road from Mammoth to Norris to

Madison mid-Feb to mid-Mar to allow lateseason access

• Snowcoach only from Norris to Canyon to

Fishing Bridge mid February to mid March

• Increase size and number of warming huts and

other day-use facilities

GT/JDRMP

• Establish 30.4 miles of new oversnow

motorized trail

• Establish 6 miles of new nonmotorized trail

• Allow all-wheeled access by plowing the

Moose-Wilson and Antelope Flats Roads

• Allow both snowmobiles and snowplanes on

Jackson Lake

• Continue current & add destination facilities

All Units

• Increase interpretive opportunities

Yellowstone

• Separate use by establishing 15 miles of new

oversnow motorized trails in the W and SW areas,

and 6 miles of new nonmotorized trails in the N

and NW areas

GT/JDRMP

• Establish 18 miles of new oversnow motorized

route by opening road north of Colter Bay to

snowmobiles

• Continue current & add destination facilities

• Increased and enhanced visitor programs facilities

and interpretive opportunities

All Units

• Continue scientific studies in re: impacts

of winter visitor use and park resources;

close selected areas or road segments if no

other possible mitigation method

Yellowstone

• Restrict backcountry skiing to use of

designated trails or routes only in

important winter range

GT/JDRMP

• Establish 8.6 miles of new nonmotorized

trail

• CDST eliminated through GTNP

• Oversnow motorized uses are eliminated

except for Grassy Lake Trail and groomed

motorized route north of Flagg Ranch

Yellowstone

• Close sections of road from the

West Entrance to Madison

Junction and Madison Junction

South to Old Faithful and the road

segments from Mammoth south to

Norris Junction and from Norris

Junction south to Madison

Junction

• Restrict skiing to use on frontcountry designated trails.

Backcountry use would be

prohibited

• Winter use season from midDecember to early March

GT/JDRMP

• Same as Alternative E

All Units

• Increase interpretive

opportunities

• Snowcoach only travel

Yellowstone

• Establish 11 miles of new

nonmotorized trail

GT/JDRMP

• Continue current & add

destination facilities

• Establish 5 miles of new

nonmotorized trail

• Open the road from Colter Bay

to the South Entrance to

snowcoaches

• Open the Grassy Lake Road

from Flagg Ranch to the west

boundary for snowcoach travel

Human Health & Safety

All Units

• Over-snow speed limit 45 mph except for

the Moran to Flagg Ranch segment, which is

35 mph.

All Units

• Prohibit late-night oversnow travel 11 P.M.. to 5 A.M.

• Implement information and enforcement program

GT/JDRMP

• Separate auto use from snowmachine use by moving CDST to new

pathway between Moran and Flagg Ranch

• Separate motor and nonmotor uses on interior park road; allow

nonmotorized use only from Taggert Lake Trailhead to Signal

Mountain

• Prohibit snowmachine use on CDST 8 P.M.. to 5 A.M. to allow for

groomers

GT/JDRMP

• Move the CDST to a widened highway

shoulder between Colter Bay and Flagg Ranch

All Units

• Prohibit late-night oversnow travel

• Implement information and enforcement program

Yellowstone

• Close East Entrance road

• Groom from West Yellowstone to Madison to Old

Faithful more frequently

GT/JDRMP

• Move the CDST to unplowed road from Colter

Bay to Flagg, and to widened highway shoulder

from Colter to Moran

• Nonmotor use only on interior park road

All Units

• Reduce nighttime oversnow speed limit to

35mph

GT/JDRMP

• Separate motorized and nonmotorized

opportunities

All Units

• Prohibit night oversnow travel,

sunset to sunrise

GT/JDRMP

• Same as Alternative E

All Units

• Prohibit late-night oversnow

travel

Local Communities & Adjacent Lands

All Units

• The 1999 Interagency Winter Visitor Use

Assessment shows relationships and

cooperative programs for winter use in the

GYA

• NPS visitor contacts are provided at visitor

centers in West Yellowstone and Jackson

Hole.

All Units

• Implement information program in cooperation with local

communities

• Establish advisory committee to phase and implement emission

standards

All Units

• Implement information program in cooperation

with local communities

All Units

• Implement information program in cooperation

with local communities

All Units

• Establish advisory committee

All Units

• Implement information program in

cooperation with local

communities

All Units

• Implement information program

in cooperation with local

communities

Natural Resources

All Units

• Enforce current sound standards, 78dB(A)

• Bio-lubes and fuels used by NPS

All Units

• Establish advisory committee

• Require new technologies

• Phase in more stringent standards for oversnow vehicle emissions

• All oversnow vehicle sound emissions must be at or less than 70

dB(A)

• Monitor natural resources at current levels of administration, and use

regulatory measures when necessary to prevent identified

disturbances resulting from winter recreation use

Yellowstone

• Continue scientific studies in re: impacts of winter visitor use and

park resources; close selected areas if no other possible mitigation

method

• Restrict nonmotorized use to designated important winter range

GT/JDRMP

• Phase in motorized use by snowplanes only on Jackson Lake

All Units

• Enforce current sound standards, 78dB(A)

• Manage wildlife same as in Alternative A

• Phase in alternative fuel/lube sales to public

Yellowstone

• Provide quiet nonmotorized environment by

restricting Norris to Canyon to Fishing Bridge

road to snowcoaches mid-Feb to mid-Mar

All Units

• Oversnow vehicle sound emissions must be at or

less than 60 dB(A)

• Phase in alternative fuel/lube sales

• Phase in more stringent standards for oversnow

vehicle emissions

Yellowstone

• Restrict nonmotorized use to designated trails in

important winter range, except in the Tower and

Mammoth areas

GT/JDRMP

• Allow motorized use by snowplanes only on

Jackson Lake (no snowmobiles on Jackson Lake)

All Units

• Establish advisory committee to

recommend emission standards for

oversnow vehicles

• Monitor natural resources at current levels

of administration, and use regulatory

measures when necessary to prevent

identified disturbances resulting from

winter recreation use

Yellowstone

• Restrict nonmotorized use in important

winter range

GT/JDRMP

• CDST would be accessed via shuttle from

east boundary to Flagg Ranch

• Eliminate motorized use on Jackson Lake

All Units

• Require new technologies for

reducing snowmobile emissions as

they are developed by industry

Yellowstone

• Close road from West

Yellowstone to Madison to Old

Faithful from Nov 1 to Apr 30

• Allow nonmotorized uses only on

groomed trails in frontcountry

• Shorten the season by two weeks

in March

GT/JDRMP

• Same as Alternative E

All Units

• Sound emissions must be at or

less than 75dB(A)

• Restrict oversnow motorized

travel to snowcoaches which

meet stringent air quality

standards (current technologies

exist that would accomplish this)

• Require new technologies as

they are made available

• Manage wildlife same as in

Alternative A

GT/JDRMP

• Discontinue all motorized use on

Jackson Lake

• Close important bighorn sheep

winter habitat to backcountry use
SUMMARY

xiv
S-2. Summary of Effects*

*Summary Statements Above Are Abbreviated And Taken Out Of Context To Provide A Quick Comparison By Element.

The Reader Is Encouraged To Review The Supporting Analysis In Chapter IV.

ALTERNATIVE A

No Action ALTERNATIVE B ALTERNATIVE C ALTERNATIVE D ALTERNATIVE E ALTERNATIVE F

ALTERNATIVE G

Preferred Alternative

Socioeconomic

• Social: continued values and beliefs conflicts

• No policy related impacts on economics

would result under alternative A.

• Continued high cost of winter visitor access.

• Negligible to minor effects on local & state

economies.

• Major negative effect on small gateway

communities (West Yellowstone).

• Moderate negative effects on total

nonmarket visitor benefits (through reduced

visitation).

• Minor to moderate benefit to low-income

visitors.

• Negligible to minor effects on local & state

economies.

• Major negative effect on small gateway

communities (West Yellowstone).

• Moderate negative effect on total nonmarket

visitor benefits (through reduced visitation).

• Minor to moderate benefit to low-income

visitors.

• Negligible to minor effect on local and state

economies.

• Minor negative effect on total nonmarket

visitor benefits (through reduced visitation).

• No short-term effects compared to current

condition.

• Negligible to minor effect on local and state

economies.

• Larger, major adverse effect on the

economies of small gateway communities

(W. Yellowstone and Gardiner).

• Minor negative effect on total nonmarket

visitor benefits (through reduced visitation).

• Minor effect on local and state economies.

• Larger, major adverse effect on the

economies of small communities within the

GYA.

• Minor negative effect on total current trip

nonmarket visitor benefits (through reduced

visitation).

Cultural Resource

• With appropriate mitigation, no adverse

effects on archeological or historic

resources, or cultural landscapes.

• With appropriate mitigation, no adverse

effects on archeological or historic

resources, or cultural landscapes.

• With appropriate mitigation, no adverse

effects on archeological or historic

resources, or cultural landscapes.

• With appropriate mitigation, no adverse

effects on archeological or historic

resources, or cultural landscapes.

• With appropriate mitigation, no adverse

effects on archeological or historic

resources, or cultural landscapes.

• With appropriate mitigation, no adverse

effects on archeological or historic

resources, or cultural landscapes.

• With appropriate mitigation, no adverse

effects on archeological or historic resources,

or cultural landscapes.

Air Quality and Public Health

• Continued minor and adverse effects from

emissions exposure parkwide.

• Continued moderate and adverse local

effects at major staging areas.

• Continued adverse impacts on employees

who work at entrances, destination, and

staging areas.

• Vehicular emissions would continue to cause

localized and perceptible visibility

impairment near vicinity of the West

Entrance, Old Faithful and Flagg Ranch.

• Emissions along heavily used roadways

would result in localized visibility

impairment.

• Major beneficial effects would occur at the

West Entrance, Old Faithful and Flagg

Ranch due to reduced PM10 and CO.

• Moderate to minor beneficial effects dye to

reduced CO and PM10 concentrations at other

locations where snowmobiling is permitted,

once strict emission requirements are

implemented.

• Minor beneficial effects due to reduced CO

concentrations along the Flagg Ranch to

Colter Bay roadway and the Teton Park Rd.

• Relative to existing condition, improved

visibility at West Entrance and Old Faithful.

• Vehicular emissions would not cause any

perceptible visibility impairment in the

vicinity of W. Entrance or along park

roadways.

• Major beneficial effects at the W. Entrance

and along the roadway to Madison and Old

Faithful.

• Moderate reductions in CO at the Old

Faithful staging area.

• Minor reductions in CO at Flagg Ranch and

along the road to Colter Bay.

• Minor to moderate adverse effects

(compared to alternative A) where oversnow

vehicles would be permitted.

• Relative to existing condition, improved

visibility at West Entrance.

• Vehicular emissions would not cause any

perceptible visibility impairment in the

vicinity of W. Entrance or along the

roadways.

• Perceptible visibility degradation could

occur in the vicinity of Old Faithful and

Flagg Ranch during periods of high use.

• Moderate and major beneficial effects at the

West Entrance and along the road to Old

Faithful.

• Increased traffic at Flagg Ranch and on the

road to Colter Bay would result in major

adverse impacts to air quality if mitigating

use limits were not implemented.

• Moderate beneficial effects would occur

where snowmobiling is permitted, once strict

emission requirements were implemented.

• Relative to existing condition, improved

visibility at W. Entrance and Old Faithful.

• Vehicular emissions would cause localized,

perceptible, visibility impairment near the

vicinity of W. Entrance and in the area

around Old Faithful and Flagg Ranch.

• Vehicular emissions along roadways would

not result in perceptible visibility

impairment.

• In the short term, effects would be the same

as described in No Action.

• In the long term, negligible to moderate

beneficial improvements in air quality near

the W. Entrance and other staging areas in

YNP-- depending on emissions standards

required by FACA committee.

• Moderate and major beneficial impacts

would occur in GTNP due to the prohibition

of snowmobiles on the roadway from Colter

Bay to Flagg Ranch and Teton Park Road.

• Vehicular emissions would continue to cause

localized and perceptible visibility

impairment near vicinity of the W. Entrance,

Old Faithful and Flagg Ranch.

• Emissions along heavily used roadways

would result in localized visibility

impairment.

• Moderate improvements to visibility in W.

Entrance vicinity.

• Negligible beneficial effects at Old Faithful.

• Negligible to minor adverse effects would

occur at Flagg Ranch.

• Moderate and major beneficial effects to air

quality would occur on the road from Flagg

Ranch to Colter Bay and Teton Park Road.

• Vehicular emissions would not cause any

perceptible visibility impairment in the

vicinity of W. Entrance or along the

roadways.

• Perceptible visibility degradation could

occur in the vicinity of Old Faithful and

Flagg Ranch during periods of high use.

• Major beneficial effects in air quality at the

W. Entrance and along the road to Old

Faithful.

• Minor beneficial effects at Old Faithful and

Flagg Ranch due to reduction in CO and

major beneficial effects from the reduction of

PM10.

• Major beneficial reductions in CO and PM10

are predicted along the roadway from Flagg

Ranch to Colter Bay.

• Vehicular emissions would not cause any

perceptible visibility impairment in the

vicinity of W. Entrance along park roadways

or in the vicinity of Old Faithful and Flagg

Ranch.

Public Safety

• Continued minor adverse effects to visitor

and employee safety along the road from W.

Entrance to Old Faithful and the CDST.

• Continued minor to moderate adverse effects

on winter visitors and employees who use

the E. Entrance.

• Moderate beneficial improvements due to

mass transit in YNP and separation of uses

in GTNP, including new CDST pathway.

• Minor beneficial improvements in the parks

due to the introduction of several positive

safety-oriented measures in the absence of

any additional safety risks.

• Moderate adverse effects in YNP due to the

potential for increasing visitor conflicts and

vehicle/animal collisions.

• Minor improvement due to widened

highway shoulder for the CDST.

• Minor beneficial improvements in the parks

due to the introduction of several positive

safety-oriented measures in the absence of

any additional safety risks.

• Minor improvement due to widened

highway shoulder for the CDST and

removal of wheeled vehicle traffic from

Colter Bay to Flagg Ranch.

• Negligible improvements, as compared to

alternative A, in all three-park units due to

oversnow nighttime speed limits.

• Moderate beneficial improvements in GTNP

due to decrease in oversnow motorized

travel and elimination of the CDST in the

park.

• Major beneficial improvements, as compared

to alternative A, in YNP and GTNP as a

result of the nighttime closure and the

overall elimination of oversnow travel on

north and west side of YNP and the CDST.

• Minor to moderate improvements (at

existing use levels) due to backcountry

closures.

• Improvements would be major and

beneficial, as compared to alternative A, in

the parks due to the elimination of all

potential snowmobile accidents,

implementation of park- wide mass transit

system. And removal of wheeled vehicle

traffic from Colter Bay to Flagg Ranch.

Geothermal Resources

• Minor adverse long term impacts to

geothermal features near groomed roads,

around destination areas, and near winter

trails in the backcountry.

• As in alternative A minor adverse impacts

would occur near staging areas, roads,

destination areas, and near winter trails.

• Adaptive management provisions would

mitigate these effects over the long term.

• Minor incremental long-term degradations

to, and in some cases, permanent loss of

certain features because of increased access.

• General continued adverse impacts as in A

for features near existing groomed routes

and facilities.

• As in alternative A minor adverse impacts

would occur near staging areas, roads,

destination areas, and near winter trails.

• Adaptive management provisions would

mitigate these effects over the long term.

• Elimination of human access to backcountry

and along the north and west road segments

would greatly decrease potential impacts.

• Negligible to minor improvements (over

alternative A) due to mass transit and

enhanced visitor awareness programs.

• As in alternative A, minor adverse impacts

would occur near staging areas, roads,

destination areas and near winter trails.

• Adaptive management provisions would

mitigate these effects over the long term.

Water and Aquatic Resources

• Deposition into snow pack would continue

to occur from two-cycle engine emissions

along groomed park roads in YNP and

GTNP.

• Continued high risk of adverse effects on

water quality, wetlands, and aquatic

resources where oversnow motorized use

closely parallels rivers and other bodies of

water (22% of the groomed trail system and

on the frozen surface of Jackson Lake).

• Protection through the monitoring and

scientific studies provisions. If adverse

effects occur that cannot be mitigated, the

activity specifically causing the effect would

be terminated.

• Moderately decreases the risk of adverse

effects on water quality, wetlands, and

aquatic resources where oversnow motorized

use closely parallels rivers and other bodies

of water (high-risk segments along the

Madison and Firehole Rivers). Vehicle miles

traveled on high-risk segments reduced by

65%.

• Minor improvements on the effects from

pollution deposited in the snow by selling

ethanol-blend fuels and low-emission

lubricants.

• Moderately decreases the risk of adverse

effects on water quality, wetlands, and

aquatic resources where oversnow motorized

use closely parallels rivers and other bodies

of water (high risk segments along the

Madison and Firehole Rivers). Vehicle

miles traveled on high-risk segments reduced

by 62%. Snowmobiles phased out from

Jackson Lake.

• Slightly decreases the risk of adverse effects

on water quality, wetlands, and aquatic

resources where oversnow motorized use

closely parallels rivers and other bodies of

water (high risk segments along Yellowstone

Lake). Vehicle miles traveled on high-risk

segments reduced by 14%, no snowmobiles

on Jackson Lake.

• Same as Alternative A for YNP.

• In GTNP, eliminates risk of pollutants

entering Jackson Lake.

• Protection through the monitoring and

scientific studies provisions. If adverse

effects occur that cannot be mitigated, the

activity specifically causing the effect would

be terminated.

• Greatly decreases the risk of adverse effects

on water quality, wetlands, and aquatic

resources where oversnow motorized use

closely parallels rivers and other bodies of

water (high-risk segments along the

Madison, Firehole, Gardner and Gibbon

Rivers and Jackson Lake). Vehicle miles

traveled on high-risk segments reduced by

74%. All motorized use eliminated from

Jackson Lake.

• Greatly decreases the risk of adverse effects

on water quality, wetlands, and aquatic

resources where oversnow motorized use

closely parallels rivers and other bodies of

water (high risk segments along the Madison,

Firehole, Gardner and Gibbon Rivers).

Vehicle miles traveled on high-risk segments

reduced by 84%. All motorized use

eliminated from Jackson Lake.

• Protection through the monitoring and

scientific studies provisions. If adverse

effects occur that cannot be mitigated, the

activity specifically causing the effect would

be terminated.
SUMMARY

xvi
ALTERNATIVE A

No Action ALTERNATIVE B ALTERNATIVE C ALTERNATIVE D ALTERNATIVE E ALTERNATIVE F

ALTERNATIVE G

Preferred Alternative

Wildlife - Ungulates

• Effects of groomed surfaces and plowed

roads on animal movements - unknown to

what extent any beneficial effects outweigh

negative effects.

• Effects related to displacement and

fragmentation are minor to moderate,

adverse, and short-term.

• Risk of collisions with snowmobiles is

negligible, adverse, and short-term.

• Risk of collisions with wheeled vehicles is

minor, adverse, and short-term.

Effects of nonmotorized use – adverse, minor

and short-term.

• Effects of unregulated backcountry

nonmotorized use on displacement from

preferred habitats – adverse, moderate and

short-term. Impacts to bighorn sheep in

GTNP would be moderate to major and longterm if no mitigation is applied.

• Effects from visitor use of winter support

facilities on displacement would be adverse,

minor, and short-term.

• Effects related to groomed roads would

decrease due to the plowing of the road from

West Yellowstone to Old Faithful. Plowing

may increase road-kill mortalities, but

implementation of mass transit would

ameliorate effects.

• Effects related to snowmobiles would

decrease in YNP. In GTNP, separation of

the CDST from the roadway may increase

collisions and displacement effects.

• Effects related to nonmotorized use would

be negligible; additional routes would not be

located in areas critical to wildlife.

• Backcountry uses in certain winter ranges

would be restricted or prohibited in YNP,

thus effects would decrease and become

negligible to minor. Impacts to bighorn

sheep in GTNP would remain the same -

moderate to major and long-term.

• Adaptive management would be employed

to adjust management should impacts to

wildlife be demonstrated through ongoing

monitoring and research.

• Effects on wildlife associated with oversnow

and wheeled vehicles increase. Plowing of

the road from Yellowstone to Old Faithful to

accommodate private vehicles and the

establishment of a groomed snowmobile trail

from GTNP’s south boundary to Moran

along the eastern park boundary may

negatively impact ungulates, especially on

limited winter range in GTNP. The periodic

diversion of the CDST near Jackson Lake

could impact moose.

• Effects related to nonmotorized activities

remain the same as Alternative A, but may

slightly increase because more opportunities

are provided. Moose may be impacted near

the Gros Ventre River in GTNP.

• Effects related to backcountry use would

remain the same as Alternative A.

• More winter facilities are proposed;

including campsites in YNP – thus

associated effects would increase.

• Effects of groomed roads and snowmobiles

would decrease in both parks. In GTNP, no

opportunities for snowmobile use of

ungroomed trails would exist.

• Effects related to plowed roads and wheeled

vehicles would remain the same in YNP and

would decrease in GTNP because the road

from Colter Bay to Flagg Ranch would not

be plowed.

• Effects of unregulated backcountry

nonmotorized use in YNP on all ungulate

species would be negligible to minor due to

limitations on backcountry use and closure

of the E. Entrance. In GTNP, effects of

nonmotorized use on ungulates may increase

because more use would be expected in areas

where snowmobiling would now be

prohibited (e.g., Antelope Flats).

• Overall, this alternative decreases the effects

on ungulates relative to Alternative A.

• Miles of groomed surface in GTNP greatly

decreased, eliminating snowmobile use and

its effects, from most of the park. Moose

would benefit in GTNP by the elimination of

the CDST. Effects would be much lower in

magnitude than in Alternative A. Effects in

YNP would be the same as Alternative A.

• Effects of nonmotorized use in GTNP would

decrease in the Antelope Flats area, thus

benefiting ungulates near important winter

range in the park.

• Effects of unregulated backcountry

nonmotorized use in YNP on all ungulate

species would negligible to minor due to

limitations on backcountry use.

• Overall, the effects on ungulates are

generally the same (YNP) or much less than

Alternative A (GTNP).

• Adaptive management would be employed

to adjust management should impacts to

wildlife be demonstrated through ongoing

monitoring and research.

• Effects of groomed surfaces and oversnow

motorized use are negligible. In YNP,

closing the west side of the park protects

important ungulate habitat.

• Miles of groomed surface in GTNP greatly

decrease, effectively eliminating

snowmobile use, and its effects, from most

of the park. Moose would benefit in GTNP

by the elimination of the CDST.

• In YNP, all nonmotorized use in the

backcountry is prohibited, thus eliminating

all effects associated with off-trail travel.

• Overall effects would be much lower in

magnitude than in Alternative A.

• The effects of groomed surfaces would be

less than Alternative A in GTNP. Risk of

collision from oversnow vehicles would be

nearly eliminated in all parks due to the

prohibition on snowmobiling and late night

travel. Moose would benefit in GTNP by the

elimination of the CDST.

• Mass transit would greatly reduce vehicle

miles traveled and allow for the use of

trained drivers. Consequently there would be

the ability to control where and when stops

are made. This feature would potentially

benefit all species.

• Effects related to plowed roads would be the

same as Alternative A for YNP, and

decreased in GTNP due to the elimination of

wheeled vehicles north of Colter Bay.

• In all parks, restrictions on backcountry

travel would minimize effects associated

with off-trail travel. Effects on bighorn sheep

in GTNP would be eliminated because

important sheep habitats would be closed to

winter use.

• Adaptive management would be employed to

adjust management should impacts to

wildlife be demonstrated through ongoing

monitoring and research.

Wildlife – Threatened and Endangered Species

• Effects of groomed surfaces on lynx

unknown; negligible to major depending

upon lynx abundance, distribution.

• Displacement effects of oversnow vehicles

are adverse, negligible, and short-term.

• Risk of collision with wheeled vehicles

negligible to minor for grizzly bears, wolves.

• Effects of nonmotorized use: adverse,

negligible, short-term on bald eagles; no

effect on grizzly bears; no known effect on

lynx, wolves.

• Effects of unregulated backcountry

nonmotorized use: adverse, minor, and shortterm on bald eagles; adverse, negligible,

short-term on grizzly bears; no known effect

on lynx and wolves.

• Effects of winter support facilities: adverse,

negligible, short-term on grizzly bears;

adverse, minor, short-term on wolves.

• Effects would be generally as stated for

ungulates.

• Impacts to lynx may increase in GTNP

because some of the new groomed routes are

in potential lynx habitat (e.g., Two Ocean

Lake, and diversions of the CDST).

• The new snowmobile route in GTNP may

displace ungulates, and consequently

wolves, from the southeastern part of the

park.

• The extension of the winter use season from

the S. Entrance to West Thumb, combined

with increased winter support facilities may

result in more grizzly bear-human conflicts

as bears emerge from hibernation.

• Closure and elimination of use on the road

from Fishing Bridge to the E. Entrance in

YNP would generally benefit all species

actively using habitat on the entire east side

of the park.

• Most other effects are generally the same as

Alternative A with the exception of the

elimination of unregulated backcountry use

in YNP, which decreases effects, and the

development of warming huts at Jenny Lake

which may increase effects on lynx.

• Slightly decreases the potential effects

compared to Alternative A. The elimination

of snowmobiling from most of the GTNP

would reduce effects associated with packed

trails and displacement; restrictions on

backcountry travel in YNP may decrease

displacement effects associated with off-trail

travel.

• Adaptive management would be employed

to adjust management should impacts to

wildlife be demonstrated through ongoing

monitoring and research.

• The closure of the winter season after 1

March would minimize the potential for

bear-human confrontations and conflicts that

could occur after the emergence of grizzly

bears in the spring.

• Closure of the roads from W. Entrance and

Mammoth to Old Faithful would generally

benefit listed species habitats on the entire

west side of YNP.

• In all parks, if protected species activity is

detected, park managers can close the area to

human activity to mitigate disturbance.

• Potential effects would be the same or less

than Alternative A.

• Effects related to oversnow vehicles on

groomed roads decrease, a potential benefit

to all species. Most visitors would be

traveling on NPS-managed snowcoaches

having the ability to control where and when

stops are made.

• Use of snowcoaches could continue to

displace lynx as routes pass through lynx

habitat, but effects of snowcoaches would be

less than those of snowmobiles being fewer

in number, slower, and quieter.

• Effects related to plowed roads may decrease

impacts to wolves/lynx because wheeled

vehicles eliminated from Colter to Flagg.

• Earlier opening increases potential for

grizzly/human conflicts in YNP. Restrictions

in backcountry areas would mitigate impact.

• Effects of backcountry travel decrease.

• Adaptive management used to adjust

activities if impacts to wildlife are found.

Wildlife –Species of Special Concern

• Effects of groomed surfaces negligible.

• Displacement effects of oversnow vehicles

would be negligible to minor (swans in

YNP).

• Effects of plowed roads on collisions and

displacement would be negligible.

• Effects of nonmotorized use in the front

country – negligible (wolverines, sagebrush

lizard) to minor (swans). In swan habitat, use

may cause minor, short-term displacement

and avoidance.

• Effect of winter support facilities would be

negligible to minor.

• Effects would be generally as stated for

ungulates.

• Effects of motorized wheeled vehicles

increase in YNP and effects of snowmobiles

increase in GTNP. Swans may be affected

in YNP as a result of private vehicles

stopping near open water habitats.

• Effects of nonmotorized activities in the

front and backcountry are generally the same

as Alternative A.

• Effects related to huts increase because the

number of proposed huts increases.

• The elimination of unregulated backcountry

use in YNP may decrease associated effects.

• Closure of the E. Entrance in YNP

eliminates the need for avalanche control

and thus may benefit wolverines. This

closure and elimination of use on the road to

Fishing Bridge would generally benefit

species actively using habitat on the entire

east side of the park.

• Other effects generally the same as

Alternative A.

• Effects the same as in alternative A.

• Adaptive management would be employed

to adjust management should impacts to

wildlife be demonstrated through ongoing

monitoring and research.

• Closure of the roads from W. Entrance and

Mammoth to Old Faithful would generally

benefit habitats on the entire west side of

YNP, and potential effects on trumpeter

swans would be eliminated in those areas.

• Effects in GTNP would be lowered due to

the virtual elimination of snowmobile use.

• If protected species activity is known to

occur in an area, park managers can close the

area to human activity to mitigate

disturbance.

• For all parks, overall effects are the same or

less than Alternative A.

• Effects related to oversnow motorized

vehicles are reduced because no

snowmobiles would be permitted in the

parks.

• Effects related to groomed surfaces would

decrease in GTNP benefiting martens.

• The majority of visitors would be traveling

on NPS-managed snowcoaches, and there

would be the ability to control where and

when stops are made, benefiting all species.

• Effects associated with backcountry use are

reduced from those in Alternative A. Bighorn

sheep closures may benefit wolverines.

• Adaptive management would adjust activities

should impacts to wildlife be demonstrated.

Natural Soundscapes

• Current non-natural sounds impact the

soundscape in the three park units.

• Moderate to major adverse effects occur

because vehicles are audible over more than

200,000 acres, and they are audible more

than 50% of the time over more than 26,000

acres. Audibility for more than 50% of the

time is greatest relative to the W. Entrance to

Old Faithful route and from Moran to GTNP

south entrance.

• The average sound level is highest along

these routes and on Jackson Lake.

• Elimination of oversnow vehicles on the

road from W. Entrance to Old Faithful

would moderately reduce soundscape

impacts.

• Lowering all snowmachine sound emissions

from 78 dB to 70 dB would reduce the area

in which vehicles are audible more than 50%

of the time by 38%. When implemented this

would result in moderate beneficial effects.

• Sound levels 4000 feet distant from travel

ways would be reduced by a third, overall.

• Elimination of oversnow vehicles on the

road from W. Entrance to Old Faithful

would moderately reduce soundscape

impacts.

• The area in which vehicles are audible more

than 50% of the time would be increased by

22% resulting in moderate to major adverse

impacts on the soundscape.

• Sound levels 4000 feet distant from travel

ways would be slightly reduced overall

resulting in negligible improvements.

• Reduction in snowmobile sound emissions

from 78 dB to 60 dB would moderately

reduce impacts on the soundscape.

• Compared to quiet background conditions,

this alternative would reduce by 44% the

area in which vehicles are audible more than

50% of the time. Overall this alternative

would result in moderate to major beneficial

effects on the natural soundscape.

• Sound levels 4000 feet distant from travel

ways would be moderately reduced by about

half.

• Compared to quiet background conditions,

this alternative would reduce the area in

which vehicles are audible at all by 16%.

This reduction is due to the elimination of

winter motorized use on Jackson Lake.

• The alternative would not change the area in

which vehicles are audible more than 50% of

the time.

• Sound levels 4000 feet distant from travel

ways would be slightly reduced overall

resulting in negligible improvements.

• In the absence of mitigating use limits, this

alternative would increase by 24% the area

in which vehicles are audible more than 50%

of the time. This is a result of the shifting of

use from closed segments to open segments

on the south and east side of YNP.

• Sound levels 4000 feet distant from travel

ways would be reduced by about a third,

overall.

• Elimination of snowmobile sound emissions,

and limiting snowcoach dBAs in the short

term to 75, long term to 70, would

moderately reduce impacts on the

soundscape.

• Compared to quiet background conditions,

would decrease by 47% the area in which

vehicles are audible more than 50% of the

time.

• Sound levels 4000 feet distant from travel

ways would be slightly reduced overall.
SUMMARY

xviii
ALTERNATIVE A

No Action ALTERNATIVE B ALTERNATIVE C ALTERNATIVE D ALTERNATIVE E ALTERNATIVE F

ALTERNATIVE G

Preferred Alternative

Visitor Access & Circulation

• Minor adverse impacts would continue due

to the high cost of current winter access to

YNP’s interior

• Parking at some staging areas is filled to

capacity during peak use times resulting in

minor adverse impacts.

• Some conflict between motorized and

nonmotorized use occurs.

• All areas of the parks currently accessible

under alternative A would remain accessible

under alternative B.

• Visitor capacity would remain at levels equal

to the no-action alternative

• Mass transit shuttle would provide a less

expensive means of winter access resulting

in minor to moderate beneficial effects.

• Moderate long-term beneficial

improvements for safe snowmobile access

on the CDST.

• Grand Loop not available by single means of

transport.

• Although plowed roads would allow for

wheeled vehicle access in YNP, the lack of

available parking at Old Faithful, Madison

and Old Faithful would result in moderate

adverse effects due to an overall reduction in

winter visitor capacities.

• Minor to moderate long-term beneficial

improvements for safe snowmobile access

from Jackson and Dubois to GTNP/Parkway,

and north into YNP.

• Private vehicles would provide a less

expensive means of winter access.

• Grand Loop not available by single means of

transport.

• Minor adverse impacts would continue due

to the high cost of winter access to YNP’s

interior.

• Minor adverse effects would occur to overall

park access because of E. Entrance closure

in YNP. Winter season visitors using the E.

Entrance represent 3% of winter season

visitation or approx. 4,100 visitors

• Negligible adverse effects to park access

would occur in GTNP. Moderate long-term

beneficial improvements for safe

snowmobile access on the CDST.

• Minor adverse impacts would continue due

to the high cost of winter access to YNP’s

interior.

• Short-term access in YNP, same as in

Alternative A. Long-term effects are

unknown and would depend on future

management decisions related to area

closures.

• Access to GTNP in general would not

change, although modes of travel in some

areas would change. Motorized access on

Jackson Lake would be eliminated.

• Minor adverse impacts would continue due

to the high cost of winter access to YNP’s

interior.

• Major long-term adverse effect to current

visitor access patterns at YNP due to

elimination of two winter entrances.

• Effects for GTNP would be the same as

alternative E.

• The Grand Loop experience would be

eliminated.

• Minor adverse impacts would continue due

to the high cost of winter access to YNP’s

interior.

•Negligible long-term effects to YNP because

level of access is not altered, only the mode

of travel.

• Minor adverse long-term effects in GTNP

would occur because motorized access on

Grassy Lake Road and Jackson Lake would

be eliminated.

Visitor Experience

All three park units

• Little or no operational change would occur.

Visitation would be influenced by the method

of transportation available to visitors.

• For visitors who prefer to visit the parks via

snowmobile, the visitor experience would

continue to be highly satisfactory.

• Encounters with park wildlife and scenery

would continue to be primary attractions,

consequently the overall satisfaction of

current winter visitors would remain high.

• Current levels of snowmobile emissions and

sound levels would continue to detract from

critical characteristics of the desired winter

experience for many visitors resulting in

direct short-term major adverse impacts on

visitor experience.

• The perceived unsafe behavior of others and

the occurrence of visitor conflicts would

continue to have direct short-term minor to

moderate adverse effects on the experience of

some users.

• Current motorized use would continue to

deter some user groups from visiting or

returning to the parks.

All three park units

• The adaptive management provisions could

result in sections of the park being closed to

protect resources/values. Visitor

opportunities currently afforded in those

areas would be eliminated, resulting in direct

short-term adverse effects to desired winter

visitor experience. Long-term protection of

these resources would be a major beneficial

effect by providing for future enjoyment.

• The reduction of snowmobile emissions and

sound levels would in the long term greatly

enhance opportunities for solitude, clean air,

and natural quiet. This would result in

moderate to major beneficial improvements

to the desired visitor experience.

YNP

• Major to moderate adverse effects on desired

winter experience for persons who wish to

access the park via the W. Entrance via

oversnow transport.

• Plowed road from W. Entrance to Old

Faithful could create berms of snow resulting

in moderate adverse effects on opportunities

to view scenery.

• Opportunities to view wildlife and scenery as

a solitary experience would be eliminated on

the W. Entrance Road for those persons who

are limited to motorized travel.

• Would provide an opportunity for the winter

experience at Old Faithful which has not

been available to park visitors who do not

wish to or who cannot afford to ride a

snowmobile or snowcoach.

GTNP & Parkway

• Moderate beneficial changes relating to

safety by separating user groups within the

park, and by improving groomed surfaces.

• Moderate beneficial improvement due to

increased availability of information,

interpretation, and winter programs.

YNP

• Major to moderate adverse effects on desired

winter experience, affecting the current

winter visitors who access the park via the

W. Entrance using oversnow transport.

• The creation of snow berms along plowed

roadways could cause moderate adverse

effects to scenery viewing opportunities.

• The addition of motorized and nonmotorized trails would increase opportunities

for winter experiences and would result in

direct moderate beneficial improvements.

• Affects on opportunities for solitude, clean

air, and quiet (except during the late season)

would be minor to moderate and adverse,

except at W. Entrance.

• In the vicinity of Old Faithful opportunities

for clean air would be moderate and

beneficial.

• Moderate to major adverse effects would

occur due to the complexities of park travel.

• Visitors, who are unable, cannot afford, or

do not wish to ride a snowmobile or

snowcoach would have access via private

automobile to Old Faithful.

GTNP & Parkway

• A full range of winter activities would be

available to enhance opportunities for

wildlife and scenery viewing.

• Minor beneficial changes in safety due to

improvement of the CDST.

• Minor adverse effect in locating motorized

and nonmotorized uses in close proximity.

• Opportunities for use on groomed surfaces

would increase.

• Minor to moderate beneficial effect to visitor

experience due to increased availability of

information and trailside facilities.

• Major adverse effect to opportunities for

quiet and solitude. Opportunities to

appreciate clean air also adversely affected.

All three park units

• The reduction of snowmobile emissions and

sound levels would, in time, result in

moderate to major beneficial improvements

in opportunities for solitude, clean air and,

natural quiet.

• Minor beneficial effect to visitor experience

due to greatly increased availability of

information, interpretation, and winter

programs.

YNP

• The increase in trail opportunities would

provide minor to moderate beneficial effects

for all user groups.

GTNP & Parkway

• Minor to negligible adverse effects to

opportunities for wildlife and scenery

viewing.

• Major beneficial improvements relating to

safety by separating user groups within the

park.

• Widening the groomed surfaces of the CDST

and removing adjacent wheeled vehicle

traffic from Colter Bay to Flagg Ranch

would be a moderately beneficial effect.

All three park units

• The adaptive management provisions could

result in sections of the park being closed to

protect resources/values. Visitor

opportunities currently afforded in those

areas would be eliminated, resulting in direct

adverse effects to desired winter visitor

experience. Long-term protection of these

resources would be a major beneficial effect

by providing for future enjoyment.

YNP

• Negligible to moderate beneficial short-term

improvements in opportunities to appreciate

clean air, quiet, and solitude from the

implementation of the standards set by the

FACA committee.

GTNP & Parkway

• Wildlife and scenery viewing would remain

unchanged for nonmotorized users and

automobile occupants.

• There would be major beneficial

improvements relating to safety by

eliminating snowmachines as a source of

motor vehicle accidents, except on Grassy

Lake road.

• There would be major adverse effects on

opportunities to participate in oversnow

motorized activities.

• There would be major beneficial effects

relative to opportunities for quiet and solitude

by eliminating snowmobiles- except on the

Grassy Lake road.

• Moderate to major improvements in air

quality would result in greater opportunities

to appreciate clean air.

YNP

• The elimination of winter opportunities on

the road segments connecting the West and

North Entrances with Old Faithful would

result in major adverse effects on the desired

winter visitor experience.

• If winter use increases in other areas of the

parks minor effects are expected on visitor

experience in those areas.

GTNP & Parkway

• Same as alternative E except for decline in

experiential values around Flagg Ranch due

to possible displaced motorized oversnow

use from YNP.

All three park units

• The adaptive management provisions could

result in sections of the park being closed to

protect resources/values. Visitor

opportunities currently afforded in those

areas would be eliminated, resulting in direct

adverse effects to desired winter visitor

experience. Long-term protection of these

resources would be a major beneficial effect

by providing for future enjoyment.

• Opportunities to view wildlife and scenery as

a solitary experience would be eliminated for

those persons who are limited to motorized

travel.

• There would be major beneficial changes

relating to safety by eliminating the

possibility of snowmobile related motor

vehicle accidents.

• There would be a minor to moderate

beneficial effect to visitor experience due to

increased availability of information,

interpretation and winter programs.

• Opportunities to appreciate clean air would

be greatly improved. Where oversnow

motorized use occurs, via snowcoach, quiet

and clean air would be facilitated by

improved motorized technology.

•The elimination of snowmobiles would result

in major adverse effects to the experiences

of visitors who prefer this mode of travel.

•There would be a major beneficial effect

relative to opportunities for quiet and

solitude, for nonmotorized visitors.

*SUMMARY STATEMENTS ABOVE ARE ABBREVIATED AND TAKEN OUT OF CONTEXT TO PROVIDE A QUICK COMPARISON BY ELEMENT.

THE READER IS ENCOURAGED TO REVIEW THE SUPPORTING ANALYSIS IN CHAPTER IV.
SUMMARY

xx
xxi

CONTENTS

Summary .........................................................................................................................................................iii

Introduction .................................................................................................................................................iii

Background .................................................................................................................................................iv

Purpose and Need for Action ....................................................................................................................... v

Cooperating Agencies ................................................................................................................................ vii

States and Counties where the Proposed Action is Located ...................................................................... vii

Public Involvement before the Release of the Draft Plan and EIS ............................................................ vii

Public Involvement after the Release of the Draft Plan and EIS ..............................................................viii

Alternatives .................................................................................................................................................ix

Mitigation ................................................................................................................................................... xii

Impacts ....................................................................................................................................................... xii

Tables ..........................................................................................................................................................xxiii

Chapter I Purpose of and Need for the Action ................................................................................................. 1

Introduction .................................................................................................................................................. 1

National Park Service Mandates .................................................................................................................. 2

Purpose of and Need for Action ................................................................................................................... 6

Decision to be Made .................................................................................................................................... 8

Response to Public Comments ..................................................................................................................... 9

Background ................................................................................................................................................ 11

Consultation and Coordination .................................................................................................................. 15

Public Involvement .................................................................................................................................... 20

Major Issues ............................................................................................................................................... 23

Issues or Concerns Not Addressed in the Plans/EIS .................................................................................. 25

Other Plans and Environmental Analyses .................................................................................................. 27

Chapter II Alternatives Including the Proposed Action ................................................................................. 30

Introduction ................................................................................................................................................ 30

Formulation of Alternatives ....................................................................................................................... 30

Alternative D escription .............................................................................................................................. 31

Alternatives ................................................................................................................................................ 38

Mitigation ................................................................................................................................................... 53

Alternatives Considered but Eliminated from Detailed Study .................................................................. 60

Alternatives Suggested during the Public Comment Period ...................................................................... 62

Summary of Alternatives and Effects ........................................................................................................ 64

Chapter III Affected Environment ................................................................................................................. 99

Introduction ................................................................................................................................................ 99

Mandatory Topics ...................................................................................................................................... 99

Impact Topics Dismissed ......................................................................................................................... 100

Impact Topics Addressed ......................................................................................................................... 104

Adjacent Lands ........................................................................................................................................ 194

Chapter IV Environmental Consequences ................................................................................................... 196

Introduction .............................................................................................................................................. 196

Assumptions and Methodologies for Evaluating Impacts ....................................................................... 197

Effects Common to All Alternatives ........................................................................................................ 218

Mitigation Common to All Alternatives .................................................................................................. 221

Impacts of Implementing Alternative A — No Action ........................................................................... 222
xxii

Impacts of Implementing Alternative B .................................................................................................. 267

Impacts of Implementing Alternative C .................................................................................................. 302

Impacts of Implementing Alternative D .................................................................................................. 329

Impacts of Implementing Alternative E ................................................................................................... 354

Impacts of Implementing Alternative F ................................................................................................... 374

Impacts of Implementing Alternative G — The Preferred Alternative ................................................... 401

Direct, Indirect, and Cumulative Effects on Adjacent Lands .................................................................. 431

Relationship between Local Short-Term Uses and Long-Term Productivity ......................................... 472

Irreversible and Irretrievable Commitments of Resources ...................................................................... 473

Unavoidable Adverse Impacts ................................................................................................................. 474

Cumulative Impacts Analyses .................................................................................................................. 475

Glossary ....................................................................................................................................................... 484

Bibliography ................................................................................................................................................ 492

Index ............................................................................................................................................................ 512
xxiii

FIGURES

Figure 1. Greater Yellowstone Area ............................................................................................................. 12

Figure 2. Alternative A for YNP ................................................................................................................... 73

Figure 3. Alternative B for YNP ................................................................................................................... 75

Figure 4. Alternative C for YNP ................................................................................................................... 77

Figure 5. Alternative D for YNP ................................................................................................................... 79

Figure 6. Alternative E for YNP ................................................................................................................... 81

Figure 7. Alternative F for YNP . .................................................................................................................. 83

Figure 8. Alternative G for YNP ................................................................................................................... 85

Figure 9. Alternative A for GTNP and the Parkway . ................................................................................... 87

Figure 10. Alternative B for GTNP and the Parkway ................................................................................... 89

Figure 11. Alternative C for GTNP and the Parkway ................................................................................... 91

Figure 12. Alternative D for GTNP and The Parkway ................................................................................. 93

Figure 13. Alternatives E and F for GTNP and the Parkway . ...................................................................... 95

Figure 14. Alternative G for GTNP and the Parkway . ................................................................................. 97

Figure 15. County map. .............................................................................................................................. 104

Figure 16. Percentage of time snowmachines were audible during daytime audibility logging ................ 165

Figure 17. A-weighted sound levels by hour, Old Faithful, YNP, March 2, 2000..................................... 166

Figure 18. A-weighted sound levels by hour, West Thumb, YNP, March 1, 2000.................................... 166

Figure 19. A-weighted sound levels by hour, Grand Canyon of the Yellowstone, February 29, 2000...... 167

Figure 20. A-weighted sound levels by hour, Pelican Valley, YNP, February 29, 2000 ........................... 167

Figure 21. A-weighted sound levels by hour, Flagg Ranch, March 2, 2000 .............................................. 168

Figure 22. A-weighted sound levels by hour, Colter Bay, GTNP, March 3, 2000..................................... 168

Figure 23. A-weighted sound levels by hour, Pacific Creek, GTNP, March 6, 2000 169

Figure 24. A-weighted sound levels by hour, Taggart Lake, GTNP, March 6, 2000................................. 169

TABLES

Table 1. Cooperating agencies ....................................................................................................................... 16

Table 2. Summary of comments received during scoping. ............................................................................ 21

Table 3. Management zones. ........................................................................................................................ 32

Table 4. Monitoring indicators. .................................................................................................................... 34

Table 5. Adaptive management indicators. ................................................................................................... 36

Table 6. Average total annual and daily peak oversnow use. ....................................................................... 54

Table 7. Point system for capping oversnow vehicle use. ............................................................................ 57

Table 8. Interim cap on snowmobile use in alternative G for Yellowstone/Grand Teton/Parkway area road

segments. ................................................................................................................................................ 59

Table 9. Summary of The Citizens’ Solution. .............................................................................................. 62

Table 10. Summary of Revised Alternative E . ............................................................................................. 63

Table 11. Summary of alternatives ............................................................................................................... 65

Table 12. Summary of alternative effects. .................................................................................................... 67

Table 13. Industry breakdown of employment (Number of individuals employed for the five-county GYA 

in 1996). ............................................................................................................................................... 107

Table 14. Total earnings by major industry for three-state area and for five-county GYA . ................................. 107

Table 15. West Entrance YNP winter visits and West Yellowstone resort tax collections. ....................... 110

Table 16. Comparative statistics on economic status (1989). ..................................................................... 111
TABLES

xxiv

Table 17. Preferred policy for allowing winter access to Old Faithful : winter visitor sample. .................. 112

Table 18. Preferred policy for allowing access to Old Faithful by residents and nonresidents: summer

visitor sample. ...................................................................................................................................... 113

Table 19. Respondent preference for alternative management options for winter access to Old Faithful : 

random phone sample. ......................................................................................................................... 113

Table 20. Level of agreement and disagreement with statements regarding winter use management, by

sample population. ............................................................................................................................... 114

Table 21. Visitors’ preference for bison management policies that could curtail motorized winter access

into YNP : Winter visitors. ................................................................................................................... 115

Table 22. Visitors’ preference for bison management policies that could curtail motorized winter access

into YNP by residents and nonresidents: Summer visitors. ................................................................. 115

Table 23. Respondents’ preference for alternative winter access bison management: Phone survey

respondents. ......................................................................................................................................... 115

Table 24. Social Values : Level of agreement and disagreement with statements regarding. ..................... 116

Table 25. Reported respondent participation in winter activities. .............................................................. 116

Table 26. Frequency of participation in activity: snowmobiling. ............................................................... 117

Table 27. Frequency of participation in activity: cross-country skiing. ..................................................... 117

Table 28. Primary ambient air quality standards. ....................................................................................... 122

Table 29. Carbon monoxide emissions study results. ................................................................................. 124

Table 30. Particulate matter emissions study results. ................................................................................. 125

Table 31. Volatile organic compound emissions study results. .................................................................. 125

Table 32. Case incident reports from December-March 1995-2000. .......................................................... 127

Table 33. EMS reports by activity type from December-March 1995-2000—YNP ................................. 128

Table 34. Case incident reports from December-March 1995-2000. ......................................................... 132

Table 35. EMS reports by activity type from December-March 1995-2000. ............................................. 133

Table 36. Quantitative and qualitative descriptions of typically occurring sounds. ................................... 157

Table 37. Natural background sound levels by type of site. ....................................................................... 168

Table 38. Historic resources of YNP — National Historic Landmarks (NHL ) or listed in the National 

Register — of Historic Places (NHRP). .............................................................................................. 169

Table 39. Historic resources of GTNP listed in the National Register of Historic Places . ....................... 170

Table 40. Winter lodging facilities and numbers of rooms. ....................................................................... 178

Table 41. Average winter parking capacity in YNP destination areas. ...................................................... 179

Table 42. Winter use activities in YNP . ..................................................................................................... 181

Table 43. Winter use visitors in YNP — by entrance station. .................................................................... 182

Table 44. Winter use activities in YNP — North Entrance ........................................................................ 183

Table 45. Winter use activities in YNP — West Entrance ......................................................................... 184

Table 46. Winter use activities in YNP — East Entrance . ......................................................................... 184

Table 47. Winter use activities in YNP — South Entrance ........................................................................ 185

Table 48. Sites Visited in February 1995. ................................................................................................... 185

Table 49. Winter recreational visits, by year, in GTNP .............................................................................. 186

Table 50. Winter use activities in GTNP .................................................................................................... 186

Table 51. Winter recreational visits in and adjacent to GTNP . .................................................................. 187

Table 52. Survey: Primary reasons for visitation. ....................................................................................... 191

Table 53. Survey: Important reasons for snowmobiling. ............................................................................ 192

Table 54. Major issues. ................................................................................................................................ 197

Table 55. Types of effects. ........................................................................................................................... 198

Table 56. Definition of impacts to socioeconomics ..................................................................................... 198

Table 57. Selected locations for modeling application. ............................................................................... 203

Table 58. Definition and intensity of impacts to air quality and public health ............................................ 207

Table 59. Definition of impacts to public safety .......................................................................................... 208

Table 60. Definition of impacts to water and aquatic resources .................................................................. 210

Table 61. Definition of impacts to wildlife, including federally protected species and species of special

concern. ................................................................................................................................................ 211

Table 62. Reference wheeled and oversnow vehicle noise emission levels. ............................................... 213

Table 63. Definition of impacts to visitor access and circulation. ............................................................... 217

Table 64. Definition of impacts to visitor experience. ................................................................................. 218

Table 65. Distances to limits of audibility for individual vehicle pass-bys in open and forested terrain and in

average and quiet background conditions. ........................................................................................... 220
xxv

Table 66. Maximum 1-hour average CO concentrations for alternative A . ................................................ 223

Table 67. Maximum 8-hour average CO concentrations for alternative A . ................................................ 224

Table 68. Vehicle contribution to CO concentrations for alternative A ...................................................... 224

Table 69. Maximum 24-hour average PM 

 10 

 concentrations for alternative A ............................................. 225

Table 70. Vehicle contribution to PM 

 10 

 concentrations for alternative A . .................................................. 225

Table 71. Relative risks considering current oversnow motorized use. ...................................................... 233

Table 72. Acres of park land affected by vehicle audibility. ....................................................................... 261

Table 73. Average hourly L eq  from wheeled and oversnow vehicle noise at two distances to each road

segment for alternative A ..................................................................................................................... 262

Table 74. Existing winter use visitation by facility or destination area. ...................................................... 263

Table 75. Alternative A current motorized use. ........................................................................................... 264

Table 76. YNP visitor opportunities. ........................................................................................................... 265

Table 77. GTNP and the Parkway visitor opportunities. ............................................................................. 265

Table 78. Maximum 1-hour average CO concentrations for alternative B . ................................................ 273

Table 79. Maximum 8-hour average CO concentrations for alternative B . ................................................ 273

Table 80. Vehicle contribution to CO concentrations for alternative B . ..................................................... 273

Table 81. Maximum 24-hour average PM 

 10 

 concentrations for alternative B ............................................. 274

Table 82. Vehicle contribution to PM 

 10 

 concentrations for alternative B .................................................... 274

Table 83. Snowmachines and associated risk levels for alternative B . ....................................................... 277

Table 84. Acres of park land affected by vehicles audibility for alternative B . .......................................... 290

Table 85. Average hourly L eq  from wheeled and oversnow vehicle noise at two distances to each road

segment for alternative B ..................................................................................................................... 291

Table 86. Alternative B motorized use. ....................................................................................................... 295

Table 87. YNP Visitor opportunities available under alternative B ............................................................ 297

Table 88. GTNP Visitor opportunities available under alternative B .......................................................... 301

Table 89. Maximum 1-hour average CO concentrations for alternative C . ................................................ 304

Table 90. Maximum 8-hour average CO concentrations for alternative C . ................................................ 305

Table 91. Vehicle contribution to CO concentrations for alternative C . ..................................................... 305

Table 92. Maximum 24-hour average PM 

 10 

 concentrations for alternative C ............................................. 305

Table 93. Vehicle contribution to PM 

 10 

 concentrations for alternative C .................................................... 305

Table 94. Snowmachines and associated risk levels for alternative C . ...................................................... 308

Table 95. Acres of park land affected by vehicle audibility for alternative C ............................................. 321

Table 96. Average hourly L eq  from wheeled and oversnow vehicle noise at two distances to each road

segment for alternative C ..................................................................................................................... 322

Table 97. Alternative C motorized use. ....................................................................................................... 324

Table 98. YNP Visitor opportunities available under alternative C ............................................................ 325

Table 99. GTNP Visitor opportunities available under alternative C .......................................................... 328

Table 100. Maximum 1-hour average CO concentrations for alternative D . .............................................. 331

Table 101. Maximum 8-hour average CO concentrations for alternative D . .............................................. 331

Table 102. Vehicle contribution to CO concentrations for alternative D .................................................... 332

Table 103. Maximum 24-hour average PM 

 10 

 concentrations for alternative D .......................................... 332

Table 104. Vehicle contribution to PM 

 10 

 concentrations for alternative D . ................................................ 333

Table 105. Snowmachines and associated risk levels for alternative D . ..................................................... 335

Table 106. Acres of park land affected by vehicle audibility for alternative D ........................................... 346

Table 107. Average hourly L eq  from wheeled and oversnow vehicle noise at two distances to each road

segment for alternative D ..................................................................................................................... 347

Table 108. Alternative D motorized use. ..................................................................................................... 349

Table 109. YNP Visitor opportunities available under alternative D .......................................................... 350

Table 110. GTNP Visitor opportunities available under alternative D . ...................................................... 352

Table 111. Maximum 1-hour average CO concentrations for alternative E ................................................ 355

Table 112. Maximum 8-hour average CO concentrations for alternative E ................................................ 355

Table 113. Vehicle contribution to CO concentrations for alternative E . ................................................... 355

Table 114. Maximum 24-hour average PM 

 10 

 concentrations for alternative E . .......................................... 355

Table 115. Vehicle contribution to PM 

 10 

 concentrations for alternative E .................................................. 356

Table 116. Snowmachines and associated risk levels for alternative E ....................................................... 358

Table 117. Acres of park land affected by vehicle audibility for alternative E ........................................... 366

Table 118. Average hourly L eq  from wheeled and oversnow vehicle noise at two distances to each road

segment for alternative E . .................................................................................................................... 369
xxvi

Table 119. Alternative E motorized use. ..................................................................................................... 370

Table 120. YNP Visitor opportunities available under alternative E . ......................................................... 371

Table 121. GTNP Visitor opportunities available under alternative E ........................................................ 373

Table 122. Maximum 1-hour average CO concentrations for alternative F ................................................ 377

Table 123. Maximum 8-hour average CO concentrations for alternative F ................................................ 378

Table 124. Vehicle contribution to CO concentrations for alternative F ..................................................... 378

Table 125. Maximum 24-hour average PM 

 10 

 concentrations for alternative F . .......................................... 378

Table 126. Vehicle contribution to PM 

 10 

 concentrations for alternative F .................................................. 379

Table 127. Snowmachines and associated risk levels for alternative F ....................................................... 382

Table 128. Acres of park land affected by vehicle audibility for alternative F . .......................................... 393

Table 129. Average hourly L eq  from wheeled and oversnow vehicle noise at two distances to each road

segment for alternative F . .................................................................................................................... 394

Table 130. Alternative F motorized use. ...................................................................................................... 395

Table 131. YNP Visitor opportunities available under alternative F ........................................................... 398

Table 132. GTNP Visitor opportunities available under alternative F ........................................................ 400

Table 133. Visitation response to alternative G changes in winter park access: by visitor category. ......... 401

Table 134. Estimated economic output and employment impacts of alternative winter management options. 

.............................................................................................................................................................. 405

Table 135. Maximum 1-hour average CO concentrations for alternative G . .............................................. 407

Table 136. Maximum 8-hour average CO concentrations for alternative G . .............................................. 408

Table 137. Vehicle contribution to CO concentrations for alternative G .................................................... 408

Table 138. Maximum 24-hour average PM 

 10 

 concentrations for alternative G ........................................... 409

Table 139. Vehicle contribution to PM 

 10 

 concentrations for alternative G . ................................................ 409

Table 140. Snowmachines and associated risk levels for alternative G . ..................................................... 410

Table 141. Acres of park land affected by vehicle audibility for alternative G ........................................... 422

Table 142. Average hourly L eq  from wheeled and oversnow vehicle noise at two distances to each road

segment for alternative G ..................................................................................................................... 423

Table 143. Alternative G motorized use. ..................................................................................................... 425

Table 144. YNP Visitor opportunities available under alternative G .......................................................... 426

Table 145. Visitor opportunities available under alternative G ................................................................... 429
1

CHAPTER I

PURPOSE OF AND NEED FOR THE ACTION

INTRODUCTION

In 1990 a Winter Use Plan was completed for Yellowstone National Park (YNP), Grand

Teton National Park (GTNP), and the John D. Rockefeller, Jr., Memorial Parkway (the

Parkway). In 1994 the National Park Service (NPS) and U.S. Forest Service (USFS)

staff began work on a coordinated interagency report on Winter Visitor Use

Management. This effort was in response to an earlier than expected increase in winter

use. The 1990 Winter Use Plan projected 143,000 visitors for the year 2000. Winter

visitors to YNP and GTNP in 1992-93 exceeded this estimate.

In 1994 the Greater Yellowstone Coordinating Committee (GYCC), composed of

National Park Superintendents and National Forest Supervisors within the Greater

Yellowstone Area (GYA), recognized the trend toward increasing winter use and

identified concerns relating to that use. The GYCC chartered an interagency study team

to collect information relative to these concerns and perform an analysis of winter use in

the GYA. The analysis, Winter Visitor Use Management: a Multi-agency Assessment,

was drafted in 1997 and approved by the GYCC for final publication in 1999. The

assessment identifies desired conditions for the GYA, current areas of conflict, issues and

concerns, and possible ways to address them. The final document considered and

incorporated many comments from the general public, interest groups, and local and state

governments surrounding public lands in the GYA.

In May of 1997, The Fund for Animals, Biodiversity Legal Foundation, Predator Project,

Ecology Center, and five individuals filed suit in the U.S. District Court for the District

of Columbia alleging failures by the NPS to comply with the National Environmental

Policy Act (NEPA), the Endangered Species Act (ESA), and other federal laws and

regulations in connection with winter use in the three national parks. The NPS

subsequently settled the suit, in part, by an agreement to prepare a comprehensive

environmental impact statement (EIS) addressing a full range of alternatives for all types

of winter use in the parks. This EIS fulfills that portion of the agreement.

With the popularity of winter activities such as snowmobiling and ski touring growing

nationally, winter visits to the three park areas increased from virtually none 30 years ago

to more than 100,000 per year in 1980. The parks’ winter activities have become an

important part of the region’s tourism industry. Increased winter use has raised concerns

about impacts on parks’ resources and values, and placed significant demands on the
CHAPTER I

PURPOSE OF AND NEED FOR THE ACTION

2

parks’ facilities, equipment, and personnel. These demands also affect adjacent national

forests and local communities. Until recently, when increased and new uses appeared,

demands were addressed according to established NPS policies with little additional

funding or personnel. It is now apparent that winter activities are an integral part of the

visitor experience in the GYA, and that more specific policies and management direction

are needed to guide winter use in the parks and protect sensitive resources.

NATIONAL PARK SERVICE MANDATES

The Organic Act

These Plans and EIS jointly address winter use in YNP, GTNP, and the Parkway. The

NPS and its basic mandate are authorized under the NPS Organic Act (16 USC 1, 2-4)

and the General Authorities Act (16 USC 1a-1 through 1a-8):

“The Service thus established shall promote and regulate the use of the

Federal areas known as National Parks...by such means and measures as to

conform to the fundamental purposes of the said Parks...which purpose is to

conserve the scenery and the natural and historic objects and the wildlife therein

and to provide for the enjoyment of same in such manner and by such means as

will leave them unimpaired for the enjoyment of future generations.”

Comments on the Draft Environmental Impact Statement (DEIS) indicate that many

people feel they have a right to enjoy the park units using their choice of motorized

access. These commenters refer to the NPS “dual mandate” of protection and enjoyment,

citing needs of personal freedom and taxpayer rights. Such commenters tend to strongly

support snowmobile access. The NPS response is that there are no unlimited freedoms

implied in the mandate. The Organic Act clearly states such freedoms that are enjoyed in

national parks are subject to the need to protect the parks’ resources for enjoyment by

future generations. Preservation is implicit. When an activity is identified as the source

of impairment, management action must be taken.

Other comments indicate some people believe that the NPS is obligated to provide for

businesses that have become dependent on visitor use and enjoyment of the parks. Some

comments cited NPS policies to support this view, and they noted that the NPS

encouraged early use of snowmobiles to enjoy YNP, in effect becoming a partner in

developing this use. As in the personal freedom issue above, the initial and chief concern

for the NPS under its mandate is to protect parks’ resources and values. When there is a

determination of unacceptable adverse impacts on these resources, management action

must be taken even though it may affect present visitors and local economic concerns. A

great many people commented that NPS must not put economic issues above resource

issues.

The Redwood Act

The Redwood Act (March 27, 1978, P.L. 95-250, 92 Stat. 163, 16 U.S.C. 1a-1) affirms

the basic tenets of the Organic Act and provides additional guidance on national park

system management:
NATIONAL PARK SERVICE MANDATES

3

“The authorization of activities shall be construed and the protection

management and administration of these areas shall be conducted in light of the high

public value and integrity of the National Park system and shall not be exercised in

derogation of the values and purposes for which these various areas have been

established....”

The restatement of these principles of park management in the Redwood Act is intended

to serve as the basis for any judicial resolution of competing private and public values

and interests in the National Park System (Senate Report No. 95-528 on S. 1976 pg.7).

Recently the United States Department of the Interior (USDI) solicited public comment

on revised management policies for the NPS. The proposed policies, if adopted, would

revise and clarify the interpretation by the NPS of the Organic Act mandate. The

proposed policies are based on a premise that the Organic Act forbids broader categories

of impairment given the many kinds of potential harms to resources. The proposed

policies amplify the impairment analysis by addressing impairment of the resource in

terms of the duration, extent, timing, and cumulative effect of various impacts. This

creates a more comprehensive and flexible way of analyzing and managing potential

impairments.

The proposed policies define the Organic Act impairment standard as “an adverse impact

on one or more parks’ resources or values that interferes with the integrity of the park’s

resources or values, or the opportunities that otherwise would exist for the enjoyment of

them, by the present or a future generation.” Parks’ resources and values are defined by

the Organic Act’s fundamental purpose for all parks, as supplemented and clarified by

the General Authorities Act, and any additional purposes stated in a park’s establishing

legislation or proclamation, as the resources and values of a park whose conservation is

essential to the purposes for which the area was included in the national park system.

Park-Specific Legislation

The Yellowstone National Park Act (16 USC 21, et seq.), the Grand Teton National Park

Act (16 USC 406d-1 et seq.), and the John D. Rockefeller, Jr., Memorial Parkway Act

(P.L. 92-404) provide authority and direction for management of each park addressed in

this EIS and these Plans. The establishment legislation is included in Appendix C.

Other Laws

The Clean Air Act (as amended, P.L. Chapter 360, 69 Stat. 322, 42 U.S.C. 7401 et seq.)

provides for the prevention of significant deterioration of areas where air is cleaner than

national ambient air quality standards (NAAQS), and for an affirmative responsibility to

protect air quality related values including visibility. This Act also requires the

prevention of any future impairment and the remedying of any existing impairment in

Class I federal areas, which includes Yellowstone and Grand Teton National Parks.

Other laws and their implementing regulations contribute to the management of resources

in the parks, such as the Clean Water Act, National Historic Preservation Act,

Archeological Resources Protection Act, Architectural Barriers Act of 1968, Americans
CHAPTER I

PURPOSE OF AND NEED FOR THE ACTION

4

with Disabilities Act of 1990, Uniform Federal Accessibility Standards (UFAS),

Rehabilitation Act of 1973, Secretary of the Interior’s regulation 43 CFR 17-Enforcement

on the Basis of Disability in the Interior Programs, and the Endangered Species Act.

Executive Orders

Executive Orders provide additional direction that must be considered as part of the

purpose of and need for action. Executive Order (EO) 11644 (as amended by EO 11989)

Use of Off-Road Vehicles on the Public Lands states in part:

“The widespread use of such vehicles on the public lands — often for legitimate

purposes but also in frequent conflict with wise land and resource management

practices, environmental values, and other types of recreational activity — has

demonstrated the need for a unified federal policy...that will ensure that the use of

off-road vehicles on public lands will be controlled and directed so as to protect the

resources of these lands, to promote the safety of all users of those lands, and to

minimize conflicts among the various users of those lands.” Further, “[a]reas and

trails shall be located to minimize harassment of wildlife or significant disruption of

wildlife habitats” and “areas and trails shall be located to minimize conflicts

between off-road vehicle use and other existing or proposed recreational uses of the

same or neighboring public lands....”

This order is amended by EO 11989, which adds:

“... the respective agency head shall, whenever he determines that the use of offroad vehicles will cause or is causing considerable adverse effects on the soil,

vegetation, wildlife, wildlife habitat or cultural or historic resources of particular

areas or trails of the public lands, immediately close such areas or trails to the type

of off-road vehicle causing such effects, until such time as he determines that such

adverse effects have been eliminated and that measures have been implemented to

prevent future recurrence.”

The order defines off-road vehicles as “...any motorized vehicle that is capable of crosscountry travel over ...snow, ice, or other natural terrain.” The order excludes vehicles

used for official administrative travel, vehicles used for emergency purposes, or any

vehicle that is expressly authorized for such travel. Oversnow motorized vehicles have

been authorized to travel in the three national parks, but only on surfaces where

motorized vehicles have been authorized to travel at other times of the year, meaning that

these vehicles have been allowed only on roads, and in GTNP on the frozen surface of

Jackson Lake and in the Potholes area (see the History section). The executive orders

clearly provide direction for the use of oversnow motorized vehicles operating on roads,

and that a determination about their impacts must be made.

Appendix C includes the full text of the executive orders described above.

Other Executive Orders considered in the purpose of and need for action are: EO 11990,

Protection of Wetlands; EO 11988, Floodplain Management; EO 12898, Federal Actions

to Address Environmental Justice in Minority Populations and Low Income Populations;

and EO 11593, Protection and Enhancement of the Cultural Environment.
NATIONAL PARK SERVICE MANDATES

5

Regulations

General provisions in park service regulations address snowmobile use (36 CFR 2.18).

Snowmobiling is generally prohibited except on designated routes and water surfaces

available for motorized use at other times. In addition, snowmobiles are prohibited

except where designated and “only when their use is consistent with the park’s natural,

cultural, scenic and aesthetic values, safety considerations, park management objectives,

and will not disturb wildlife or damage park resources” (36 CFR 2.18(c)). Section (d) of

this regulation lists additional limitations and prohibitions that apply where snowmobiles

are allowed, including noise limits, speed limits, operator requirements, and machine

appurtenances.

NPS Policies

Statements about management of visitor use, backcountry use, off-road vehicle use, and

visitor safety and protection are made in the USDI National Park Service Management

Policies (1988). On April 27, 2000 the Department of Interior announced a renewed

commitment to enforce existing NPS regulations regarding snowmobile use in national

parks. The commitment is based on the conclusion that parks have not done the requisite

studies to determine whether snowmobiles adversely affect the parks’ values and

resources or other visitors. As explained above, compliance with regulations and

executive orders depends upon such findings.6

1997 Court Settlement

Considerations embodied in the legal mandates discussed here prompted The Fund for

Animals, et al., to sue the NPS in 1997. Specifically, the suit pointed out the failure of

the NPS to: consult with USFWS on impacts of winter use on threatened or endangered

species; prepare an EIS concerning winter use; and evaluate the effects of trail grooming

on wildlife and other parks’ resources. The outcome of the suit was provided for in a

settlement agreement approved by the court in October 1997. The agreement committed

the NPS to: write an EIS and determine a new winter use plan for the three park units;

consult with USFWS; and evaluate the possible closure of a road segment in

Yellowstone.7

 

6

 News release of April 27, 2000: National Park Service Puts the Brakes on Escalating Snowmobile Use in

the National Park System.

7 Preparer’s Note: Many people who commented on the DEIS felt that the court settlement was an affirmation

of the claims and demands presented in the lawsuit. Many people disagreed with the range of alternatives

presented in the DEIS. Because of the outcome of the lawsuit, many felt a “no action” alternative, interpreted

as no grooming and no motorized use, was called for and should have been the park service’s preferred

alternative. The NPS response to this is that it agreed to prepare a comprehensive EIS that evaluates the

impacts of winter use, where “no action” is interpreted as the current management situation. Existing winter

uses must be reflected in alternatives to determine their impacts, as required by the Council on Environmental

Quality. The NPS did not agree with the claims and demands of the plaintiff in the lawsuit, but it did agree

that there are resource issues and concerns that need to be evaluated in light of the park service mandates.

The purpose and need for action, which set the scope of analysis and the range of alternatives in the EIS,

fulfill the settlement agreement.
CHAPTER I

PURPOSE OF AND NEED FOR THE ACTION

6

PURPOSE OF AND NEED FOR ACTION

The outcome of this EIS is the development of a plan for each park addressing existing

and potential impacts on resources and values from winter recreational uses. A plan of

this sort, termed “programmatic,” is general in nature. It is aimed at describing a

program for winter use by stating objectives and goals and determining the types of uses

that are consistent with those goals. It describes the conditions under which certain

activities are acceptable and provides general standards for management. It also provides

an overall allocation of lands where certain activities are or are not consistent with

objectives.

An EIS is necessary to evaluate alternative choices for plans while revealing the possible

environmental impacts of activities that may be included in the plans. Because a plan of

this type is general in nature, an analysis of environmental impacts need only be

conducted at a general level. The type and amount of data relating to possible impacts is

presented at the general level and is not exhaustively detailed and “site-specific.”

Detailed and site-specific data would be required of analysis for a specific activity, such

as the construction of a single facility.

The purpose of and need for action in an EIS is a brief statement specifying the

underlying purpose and need to which the agency is responding in proposing the

alternatives, including the proposed action. The need to develop a plan through an EIS is

indicated by the difference between overall desired condition and the conditions that

presently exist. The desired condition reflects the parks’ mandates, and is articulated

below as a series of general objectives. Documentation of the existing condition is based

on parks’ monitoring, levels of present winter recreational use, and other information

available through the winter visitor use assessment (GYCC 1999). Existing conditions

reflect management and public concern about impacts on resources and visitor

experiences that conflict with the stated objectives. The final plan will be designed to

move the existing condition toward the desired condition.

Desired Condition

Proceeding from the NPS mandates, which include legislation, regulations, executive

orders, and governing policies, the following statements summarize the desired condition

of the three parks for winter use. These bulleted statements may be viewed as objectives

for a new winter use plan:

• Visitors have a range of appropriate winter recreation opportunities from primitive to

developed. Winter recreation complements the unique characteristics of each landscape

within the ecosystem.

• Recreational experiences are offered in an appropriate setting; they do not take place where

they will irreparably impact air quality, wildlife, cultural areas, the experiences of other

parks’ visitors, or other parks’ values and resources.

• High quality facilities are provided in parks to support the need for safety and enhanced

visitor experiences.

• Conflicts among user groups are minimal.
PURPOSE OF AND NEED FOR ACTION

7

• Visitors know how to participate safely in winter use activities without damaging

resources.

• Oversnow vehicle sound and emission levels are reduced to protect employee and public

health and safety, enhance visitor experience, and protect natural resources.

Existing Condition

Despite interagency cooperative efforts, including working with other federal and state

agencies, counties, communities, and a variety of interest groups, many unresolved issues

and concerns exist about winter use in the three parks. Land managers, constituencies,

and users of public lands disagree about the appropriateness of certain uses, the amount

of various uses being provided, and the effects of those uses. These unresolved issues

and concerns contrast with the desired condition expressed above, and represent the need

for a new plan.

• Visitor Access: Access to most locations is limited to those who can afford to ride a

snowcoach or snowmobile. Access for personal motorized use via snowmobile has

increased greatly since the beginnings of the winter program in the three parks.

Snowmobile use, in current numbers, is in conflict with use of parks’ facilities by other

user groups.

• Visitor Experience: A variety of winter use conflicts has been identified involving the

relationship between users and among different user groups, which affects how people

experience the parks. At destination facilities and trails open to both motorized and

nonmotorized users, nonmotorized users express dissatisfaction with the sound, odor, and

quantity of snowmobiles. These vehicles affect the solitude, quiet, and clean air and other

resource values that many people expect and wish to enjoy in national parks.

• Visitor Safety: The current level of snowmobile accidents, unsafe users, inherent winter

risks, and conflicts between users are of concern from the standpoint of public safety.

• Resources: Parks have documented health hazards from snowmachine emissions,

harassment and unintended impacts on wildlife from groomed trails and their use,

degradation of air quality-related values, and impacts on the natural soundscape. Many

people strongly object to the degradation of inherent parks’ values, as well as how these

impacts affect people and their recreational opportunities.

Community expectations for winter visitor use in and around the parks represent a part of

the context for these issues and concerns. Different user groups are represented in all the

communities around the parks, and are the sources of many concerns. Economic

interests in communities develop in response to NPS policies and assist the public in

access to and enjoyment of parks’ experiences. Consistency in NPS policies is important

in this relationship as well as protection of parks’ resources and values.

Scope of Analysis — Range of Alternatives Considered

The scope of analysis determines the range of alternatives to be considered. The analysis

in this EIS is limited to recreation during the wintertime (about December 15 through

March 15, annually).
CHAPTER I

PURPOSE OF AND NEED FOR THE ACTION

8

Geographically, the analysis is limited to recreation management within the boundaries

of the three national park units.8 Recreational use considerations and supporting facilities

are limited to those that are technically possible at the present time or are feasible for

development and implementation.

The range of alternatives presents options for motorized and nonmotorized winter

recreational use in the three park units considering reasonably expected technological

improvements in emissions and sound of snowmachines. One alternative must evaluate

the impacts of current winter use (per the settlement agreement and CEQ regulations). In

this instance, “no action” is interpreted as current management, which is appropriate for

programmatic planning.9

The scope of this EIS, in terms of the decision to be made, is the winter recreation

program. Any winter use may overlap or potentially affect other parks’ management

concerns. These include wildlife management (particularly bison), concession facilities

and their management, and transportation infrastructure. To the extent possible, the

impact analysis considers ramifications on other management issues. However, it is not

possible in this EIS to evaluate the entire concession program, wildlife program

(including animal carrying capacities), or transportation system.

For example, existing facilities for fuel storage and solid waste storage and handling in

YNP are inadequate for current winter use levels. Wastewater treatment facilities in

YNP are insufficient at current winter and summer use levels. It is not within the scope

of this analysis to consider alternatives for improving basic infrastructure needs to

increase capacity. This is not feasible in the present fiscal climate, and given current use

levels and their impacts on resources. In addition separate analyses are proceeding to

bring some of the aging infrastructure into compliance. The scope of this analysis is a

programmatic assessment of facilities that are intrinsic to winter recreation experiences

and opportunities, such as trails and warming huts.

DECISION TO BE MADE

The decision to be made will depend upon a plan that addresses the existing management

situation and moves towards the desired conditions. The decision will be based greatly

on the environmental impacts disclosed in this document, relative to NPS mandates. It

will determine the level of allowable impact so that future generations of visitors can

enjoy undiminished parks’ resources and values. The record of decision will present the

 

8

 As a matter of process under CEQ regulations, the impacts of park management that are known or suspected

to occur at other times and places must be disclosed in the EIS. In this EIS, economic impacts outside park

boundaries are disclosed in the socioeconomic impacts section. Physical and resource effects are disclosed in

the sections on adjacent lands and cumulative impacts.

9

 Many commenters on the DEIS stated that NPS must have a “no action” alternative — meaning no

snowmobiling — to have a full range of alternatives, and that the court settlement showed that to be the

appropriate course of action. The park service’s interpretation of “no action” means no change in general

management direction from the present. The settlement agreement did not include any concessions to claims

by The Fund for Animals, nor did it remove any options within the park service’s discretion for park

management from the range of alternatives to be considered. In approving the settlement agreement, the court

asserted that a comprehensive winter use EIS (in accordance with CEQ regulations) would be written.
RESPONSE TO PUBLIC COMMENTS

9

selected alternative and the rationale for its selection, including factors considered other

than environmental impacts. Facets of the decision include:

• The alternative from the Final Environmental Impact Statement (FEIS), or those features

from several alternatives, selected to comprise a program to guide winter use management.

This part of the decision will allocate the types of uses and general conditions and locations

in which the uses are permissible. Features of various alternatives in the FEIS can be

mixed as long as the analysis clearly presents the environmental effects of separate

features.

• General standards for management within the various zones describing the selected

alternative in the FEIS. These standards will indicate a need for management change in

accordance with the plan.

• Key processes embodied in the plan’s implementation such as adaptive management, if

applicable, and specific monitoring requirements associated with the alternative that is

selected.

• Specific mitigation measures that have been identified in the EIS as necessary to reduce the

impacts of the selected alternative.

• Identification of any further actions that may be necessary to implement the decision, such

as rule changes or policy waivers.

The decision will not:

• Be contrary to existing mandates or major policies.

• Include decisions for management of other programs outside winter recreational use,

though it may impact other programs.

• Incorporate items that are more appropriately considered in other ongoing analyses or

pending decisions.

• Apply to lands outside the three park units, though it may affect them.

• Include the details of plan implementation: some general actions that are approved in the

plan could be implemented in a number of ways.10

Some specific implementation actions suggested by the plan, such as trail or warming hut

construction, will require further site-specific NEPA analysis and a project level decision.

RESPONSE TO PUBLIC COMMENTS

This section and the preceding discussion on scope of analysis and range of alternatives

respond to many comments on the DEIS that showed a need for more explanation about

the NEPA process and the decision to be made.

Many commenters expressed consternation about the lack of a “no snowmobiling”

alternative in the DEIS, and suggested that impact descriptions and data to support the

EIS and the preferred alternative were not detailed enough. In some cases the NPS has

added information to support the analysis of impacts in this FEIS. Additionally, NPS is

engaged in programmatic planning, rather than project-specific planning; therefore

analysis and data collection have been conducted on a reconnaissance level. Further,

where data is lacking or unavailable even at that level, CEQ regulations provide for the

decision process to continue based on best available data and professional application of

credible methods.

 

10 For example, the details of setting speed limits or open hours can be left to management’s discretion. Such

items could be changed as needs dictate without further environmental analysis.
CHAPTER I

PURPOSE OF AND NEED FOR THE ACTION

10

Many people stated they could not support any of the DEIS alternative “mixes.” An

inordinate amount of criticism was levied on the preferred alternative — to the point that

constructive comments on the other alternatives were greatly lacking. Three additional

“alternatives” were proposed: Revised Alternative E (in various forms provided by

cooperating agencies and the Blue Ribbon Coalition), the Citizens’ Solution (provided by

a consortium of conservation groups), and the Natural Regulation Alternative (provided

by The Fund for Animals).11 All such comments were read as the decisions that people

would like to see the NPS make, based upon their opinions about impacts and their

interpretations about laws.

The body of comment included little substantive information beyond that disclosed in the

DEIS, and did not demonstrate that an alternative (feature) did not belong in the range of

choices available for the decision maker. Given the ability of a decision maker to mix

features from the FEIS range of alternatives, much of the criticism in the public comment

does not apply to the analysis. Regarding the great amount of comment on the preferred

alternative, and perceived lack of justification for it, the NPS responds by saying that

such criticism is more appropriately applied to the decision when it is made. In fact, the

NPS changed the preferred alternative between draft and final EIS whereupon most of

these comments no longer apply.

Some commenters said that the desired conditions or objectives were too general, and

that there is no demonstrated need for management change. In effect, such comments

missed the real issues that are conveyed by statements of existing conditions. The NPS

responds by explaining that this is a programmatic EIS leading to a plan, which is general

in nature. In addition issues regarding resource impacts, health and safety, and visitor

experience are documented sufficiently by the NPS to indicate the need for major

management changes supported by a new plan.

Given the scope of analysis, the NPS developed alternatives (alternative plans) as

possible ways to proceed from the current condition toward the desired condition. The

NPS maintains that public access during the winter is an appropriate objective to be

achieved. Accommodating a variety of recreational uses is also valid. In each case,

activities must be evaluated in terms of impacts on parks’ resources and values, health

and safety, and visitor enjoyment. Alternatives that vary the location, amount and

proximity of uses are needed to assess the relative impact or change from the current

condition. The EIS expresses impacts or changes in terms that allow people to

understand how each alternative satisfies the purpose and need for action. It is

unreasonable to expect that all alternatives would address all aspects of the purpose and

need equally, or that all alternatives worthy of consideration would have no impacts. In

 

11 Most features of Revised Alternative E and The Citizens’ Solution were covered within the DEIS range of

alternatives. Certain features were either considered to be implementation details or outside the scope of

analysis. The Natural Regulation Alternative, by advocating no motorized access or groomed routes, was

considered outside the scope of analysis — although some alternatives close sections of the parks to

motorized use, and adaptive management could conceivably result in other sections being closed over time.
BACKGROUND

11

the final analysis, the NPS concludes that the purpose and need for action articulated in

the EIS is appropriate, and that the range of alternatives considered in detail is adequate.

It is the responsibility of the NPS decision maker, in this case, the Rocky Mountain

Regional Director, to weigh the environmental impacts and benefits of all alternatives

(and alternative features) considered in detail in this FEIS against the parks’ mandates.

The decision maker must consider any other factors that may weigh in the decision,

including social and economic considerations and public comments, and make a

determination about the best way to meet the need for action. The determination and its

rationale must be fully explained in a record of decision. There is no actionable or legal

decision made until that time.

BACKGROUND

Regional Setting

The GYA encompasses over 11 million acres and is considered one of the few remaining

intact temperate ecosystems on earth. Within the area, YNP comprises 2.22 million

acres, primarily in northwestern Wyoming and extending into south central Montana and

eastern Idaho. GTNP encompasses an additional 310,000 acres and the Parkway includes

24,000 acres both located in Wyoming. YNP and GTNP comprise the strategic core of

an upland plateau called the GYA (Figure1. Greater Yellowstone Area). Portions of six

national forests — Gallatin, Custer, Shoshone, Bridger-Teton, Caribou-Targhee, and the

Beaverhead-Deerlodge are within the GYA, as are the National Elk Refuge and Red

Rocks National Wildlife Refuge. Public lands make up most of the area (69%). Private

lands comprise 24% of the GYA, Indian reservations comprise 4%, and 3% of the lands

in the GYA are state lands. The GYA extends across 17 counties in three states.

Cooperative agreements and interagency planning and coordination aid in management

of the area as an ecological unit, while recognizing the different mandates of the land

management agencies.

The GYA encompasses a 3,500-square mile watershed that preserves one of the most

significant and near-pristine aquatic environments in the United States. The surface

water resources of YNP include over 1,000 streams comprising 3,785 miles of running

water, and 175 lakes with a total surface area of 108,000 acres. The dominant water

features of the parks include the headwaters of the Mississippi-Missouri and SnakeColumbia Rivers located along the Continental Divide. Major lakes in the GYA include

Yellowstone and Jackson Lakes.

The climate of the GYA features long, cold winters from November until April.

Snowfall ranges from 80 inches per season at Mammoth Hot Springs, to 200 to 400

inches at higher elevations. In the mountainous regions of YNP, 75% to 85% of annual

precipitation falls as snow, while in the interior plateau regions, 45% to 65% falls as

snow (Despain 1987). Winter snows in this region are light and powdery, although wind

and warm temperatures compact snow into heavy, dense masses. January temperatures

range from average daytime highs of 20°F to nighttime lows of -20°F, although lows
CHAPTER I

PURPOSE OF AND NEED FOR THE ACTION

12

can reach -40°F. Occasionally dry years occur with light snow conditions in the winter.

Weather conditions at YNP’s North Entrance are generally the mildest in the area.

The GYA has developed a national reputation as a winter recreation center offering

activities on national park and forest land, including snowmobiling, snowcoach tours,

downhill skiing, cross-country skiing, wildlife viewing, and winter sightseeing. The

parks and forests offer a broad range of activities to the winter visitor.

During the winter, plowed highways in the GYA provide automobile access to

communities near the parks. Towns near park entrances are Gardiner, Cooke City and

Silver Gate, and West Yellowstone in Montana; Cody, Dubois, and Jackson in Wyoming;

and Island Park, Idaho. These communities provide a full range of visitor services,

which complements the limited services offered in the parks.

History

The history of snowmobile use and policy in YNP predates the establishment of GTNP

and John D. Rockefeller, Jr., Memorial Parkway as they exist today. Yochim discusses

this history in detail, and most of the following summary is derived from this source

(1999).

Motorized oversnow use in YNP began in 1949, due primarily to the efforts of businesses

in Cody, Wyoming. In 1948, local businesses asked the NPS to plow the roads into the

park year-round. NPS declined, explaining that the roads were too poor to permit

extensive plowing, plowing would be hazardous, and interior park facilities were not

winterized. The first oversnow vehicles were snowplanes, which were the only oversnow

machines used in the park until 1955.

In 1955, the NPS launched the Mission 66 program in an effort to distribute the

increasing number of park visitors throughout the year, and ease the pressure of summer

use. Communities around Yellowstone took advantage of this program in 1957 to renew

the call for year-round plowing of park roads. The NPS in 1958 judged the proposal to

plow roads as feasible but not practical.

In 1963, the first machines identifiable as snowmobiles entered the park. Visitors on

snowmobiles increased from 1,000 in 1963 to 5,000 by 1966. During that time, six

western senators and the Wyoming governor requested that NPS reconsider its decision

not to plow roads in the winter. NPS initiated a high level commission culminating in a

congressional hearing in Jackson, Wyoming, in 1967 and a statement that transportation

in winter should be that which is most appropriate to the park. Oversnow transport

seemed to best meet that need considering scenic values and snow trenches created by

plowing. Most comments at the hearing were provided by business interests in the

Yellowstone area and elsewhere, and all strongly supported plowing the roads. The

outcome by the NPS was to deny the request, citing funding restrictions.
BACKGROUND

13

Figure 1. Greater Yellowstone Area.

click to enlarge map
CHAPTER I

PURPOSE OF AND NEED FOR THE ACTION

14

In 1968 park administrators developed the first formal winter use policy in response to

growing snowmobile use. The policy encouraged and permitted winter visitation by

oversnow vehicles on snow roads. It instituted a grooming program to make oversnow

travel more comfortable, and it authorized the park concessioner to open a lodging

facility at Old Faithful. The policy was a simultaneous rejection of the plowing request,

citing the possibility of tall snow berms interfering with the view for auto passengers and

creating hazards for wildlife. The NPS also thought that plowed roads would facilitate

through travel and hurt the economy of West Yellowstone. Consideration of restricting

use to ski and snowshoe only was rejected because the NPS felt this would render the

park’s interior inaccessible to the public.

The NPS began grooming snow roads in 1971, and the Old Faithful Snow Lodge opened

that same year. The NPS encouragement of oversnow access during this winter season

caused the demand for road plowing to decline. From 1967 to 1977 snowmobile use

increased and complaints about snowmobiles began to surface. Visitors and national

park personnel raised issues of noise, air pollution, and impacts to wildlife.

Concurrently, several studies were initiated, most of which focused on wildlife and the

impacts to them.

The growing use of off-road vehicles, including snowmobiles, prompted President Nixon

in 1972 to issue EO 11644 establishing a federal policy on off-road vehicle use in

relation to resource issues. Because of this order, Yellowstone’s superintendent

immediately legitimized snowmobile use by designating all the park’s interior roads for

their use.12 This action contrasts with actions taken in Glacier National Park, which

performed an assessment of snowmobile use and closed the park to this use. The period

from 1975 to 1982 represented continuing encouragement of the Yellowstone winter

program with expanded facilities, including the reopening of the Mammoth Hot Springs

Hotel and additional lodging at Old Faithful. Dogsleds were banned from the park due to

conflicts with snowmobiles. In 1980, bison were noticeably using groomed roads to

move about the park. Winter use had risen to about 70,000 visitors a year.

From 1983 to 1993, winter use increased steadily from 70,000 to 140,000 visitors per

year. Concerns previously raised continued to escalate along with use. In 1990 the NPS

issued the first environmental assessment of winter use, which developed a joint plan for

YNP, GTNP and the Parkway. The plan did not alter winter programs in YNP

significantly, but it did usher in the Continental Divide Snowmobile Trail (CDST) across

GTNP and the Parkway. The item most notable about winter use following the 1993-

1994 season is that the 10-year winter visitation target had been met in three years,

triggering the need for additional evaluation and planning.

During the late 1980s, business interests in Riverton, Lander, Pinedale, and Dubois,

Wyoming, engaged federal land managers to develop a trail linking the communities and

 

12 The author of this information indicates that he could find no evidence of an environmental analysis or

official finding accompanying the action to designate routes open for snowmobiles.
CONSULTATION AND COORDINATION

15

the Yellowstone snowmobile trails. The trail system, termed the CDST, was designed to

boost the year-round economies of those cities. The segment through GTNP and the

Parkway was established on an experimental basis in 1993 and operated under that status

for three years. After the trial period, parks’ officials in 1997 prepared a Finding of No

Significant Impact (FONSI) based on the 1990 environmental assessment, plan, and three

years of monitoring to approve the CDST and initiate rulemaking for snowmobile use in

the parks. GTNP forwarded a proposed rule to allow snowmobile use on the CDST

while closing the Potholes-Baseline Flats area to motorized use. To date, this rule has

not been approved by the USDI.

From 1994 until 1999, events coalesced and stressed the importance of the issue of

winter use recreation. The GYCC chartered a multi-agency working group to prepare an

assessment of winter use in the national parks and national forests of the GYA. A final

assessment report was issued in 1999 after significant involvement by state and local

government representatives. Conditions during the winter of 1996-97 caused large

numbers of bison to exit the parks (some, but not all, on groomed surfaces). Over 1,000

animals were killed for fear of brucellosis transmission to livestock. In 1997, The Fund

for Animals filed suit on NPS over winter use issues (see section on 1997 Court

Settlement earlier in this chapter).

CONSULTATION AND COORDINATION

Cooperating Agencies

State and county governments surrounding the GYA requested and were granted

cooperating agency status (40 CFR §1501.6) in December 1997 and January 1998. The

NPS requested that the USFS become a cooperating agency because of possible impacts

on surrounding national forests from changes in the parks’ winter use management; the

USFS acceded. Agreements were developed to assign formal roles in the EIS process

and establish expectations. The NPS held its first meeting with the cooperating agencies

on February 13, 1998. Appendix A discusses coordination with cooperating agencies.

Because gateway communities, counties, and states are concerned that any change in

visitor use patterns will affect local and regional economies, the primary basis for their

status as cooperating agencies is special expertise in local and regional social and

economic analysis. Each entity professed special expertise during the process of

formulating cooperating agreements (Table 1).
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PURPOSE OF AND NEED FOR THE ACTION

16

Table 1. Cooperating agencies.

Cooperating Agency Special Expertise and Available Resources According to the Agreements

US Forest Service Recreation, wildlife and fish, facilities, wilderness resources, air and water

quality, and special uses

The State of Idaho Department of Commerce: Review and analysis of data on socioeconomics

in Idaho; assistance in preparing public outreach information and planning

and organizing meetings; assistance in coordinating peer review of

socioeconomic information and data.

Department of Fish and Game: biological and wildlife resources in Idaho

that winter use activities in the park units may affect.

Department of Parks and Recreation: winter use activities near the parks.

Fremont County, ID Socioeconomic effects, snowmobile trail grooming and management

The State of Montana Socioeconomic effects; impacts on wildlife and recreational snowmobiling;

and environmental quality, including air and water quality issues.

Gallatin County, MT Winter use socioeconomic effects

Park County, MT Winter use socioeconomic effects

The State of Wyoming Department of Commerce: Review and analysis of data on socioeconomics

in Wyoming; review and analysis of information on winter use activities

near the parks; assistance in preparing public outreach information and

planning and organizing meetings; assistance in coordinating peer review of

socioeconomic information.

Department of Game and Fish: biological and wildlife resources in

Wyoming that may be affected by winter use activities near the parks.

Department of Environmental Quality: impacts to air and water quality

Park County, WY Socioeconomic effects

Teton County, WY Socioeconomic effects

In accordance with the Memoranda of Agreement signed by the NPS and the cooperating

agencies, the major responsibilities of the agencies include the following related to their

individual areas of expertise:

• Participating in the public scoping process, as well as meetings, conferences, and reviews

for the purpose of preparing the EIS

• Providing technical assistance and advice

• Providing written comments, correspondence, or other information to the lead agency to

facilitate EIS production

• Sharing and exchanging models, data, and other information

• Delivering all requested submittals according to the schedule developed by the lead agency

• Contributing staff and monetary resources

Veto or decision-making power does not accompany cooperating agency status. As the

lead agency charged with carrying out the NEPA process under Sec. 102(2)(c) of NEPA,

the NPS retains sole decision-making authority over the EIS and its process.

There were a number of comments on the DEIS relating to the designation of cooperating

agencies. Many people objected to the inclusion of the counties in particular, feeling that
CONSULTATION AND COORDINATION

17

their involvement biased the decision-making process and the EIS; others felt that the

NPS did not involve or listen to the cooperating agencies. Most cooperators stated that

there was insufficient time or information to provide adequate input to the NPS, and that

the NPS had not met the terms of the signed memoranda of agreement. Conversely,

many of the cooperating agencies commented that they had provided good information

that the NPS did not consider or incorporate. A table that illustrates the extent to which

the NPS interacted with cooperating agencies is contained in Appendix A.

In response to these DEIS comments, the NPS notes that the state and local governments

can be accorded cooperating agency status under CEQ regulations and under the Federal

Advisory Committee Act (as amended by the Unfunded Mandates Act). The NPS

believes that much of the criticism regarding the cooperating relationship stems from

extremely short time frames for producing this EIS, which is noted in the cooperating

agreements, and lack of experience. Few federal agencies have experience dealing with

such a large number of cooperating agencies on a single NEPA project. With the

exception of the USFS and the State of Montana, few of the cooperating agencies have

experience producing EISs and the analyses necessary in their areas of special expertise.13

14

The nature of special expertise was not well understood in the context of CEQ

regulations. The cooperators expected to write portions of the EIS, including the

alternatives. Although this is one possible application of cooperating status when

requested by the lead agency, the NPS never requested this. The NPS expected the

counties to make economic projections for the alternatives considered, and the states to

provide environmental impact information on lands within their jurisdictions by

alternative. Volume III of the FEIS includes the cooperating agencies’ comments on the

DEIS, along with the NPS responses to their key issues or substantive points. In

response to many comments, the NPS has provided additional explanation in this chapter.

American Indian Tribes

The NPS is committed to recognizing the past and present existence of American Indians

in the region, and the traces of their use as an important part of the cultural environment

to be preserved and interpreted. NPS initiated consultation along with scoping in May

1998 in accordance with the Presidential Memorandum of April 29, 1994, “Governmentto-Government Relations with Native American Tribal Governments” and in compliance

with a variety of laws, federal regulations, and agency management policies and

directives. NPS mailed scoping brochures to the eight contemporary American Indian

tribes then recognized by YNP and GTNP as traditionally affiliated with the GYA:

 

13 The CEQ definition of special expertise is: “statutory responsibility, agency mission, or related program

experience.” (40 CFR §1508.26)

14 Montana has a state law governing environmental policy: Montana Environmental Policy Act.

• Blackfeet • Confederated Salish and Kootenai
CHAPTER I

PURPOSE OF AND NEED FOR THE ACTION

18

• Crow

• Nez Perce

• Northern Arapahoe

• Northern Cheyenne

• Shoshone-Bannock

• Shoshone-Eastern Band

The scoping brochures provided an overview of winter recreation in the GYA. A

separate mailing summarized yearly visitation levels, described the general planning

process, presented a preliminary list of issues to be addressed, and solicited comments

regarding additional issues or concerns. A separate mailing identified the locations of 16

public meetings to be held during summer 1998 in cities and towns throughout

Wyoming, Montana, and Idaho, as well as in Salt Lake City, Denver, Minneapolis, and

Washington D.C.

By April 1999, an additional 13 contemporary tribes had been recognized by YNP and

GTNP as traditionally affiliated with the GYA:

• Assiniboine and Sioux

• Cheyenne River Sioux

• Crow Creek Sioux

• Flandreay Santee Sioux

• Gros Ventre and Assiniboine

• Kiowa Tribe of Oklahoma

• Lower Brule Sioux

• Oglala Sioux

• Rosebud Sioux

• Sisseton-Wahpeton Sioux

• Spirit Lake Sioux

• Standing Rock Sioux

• Yankton Sioux

On April 12, 1999, the NPS notified the 21 affiliated tribes by telephone of an upcoming

affiliated tribal consultation meeting to be held at YNP on May 20, at which the

Plans/EIS would be one of the planning projects and issues discussed. On April 23, NPS

faxed invitation letters to the tribal consultation meeting to the affiliated tribes, and four

days later the NPS mailed copies of the draft alternatives to the tribes. During the week

of May 3, the NPS made follow-up telephone calls to each of the tribes, to confirm

receipt of the draft alternatives and encourage participation in the affiliated tribal

consultation meeting on May 20.

Because a tribal consultation meeting for a separate project — the DEIS for the

Interagency Bison Management Plan for the State of Montana and Yellowstone National

Park — was to be held in YNP on May 21, representatives of non-affiliated tribes also

attended the affiliated tribal consultation meeting on May 20. Twenty-one

representatives of eleven tribes participated in discussions of the Plans/EIS. The 11

tribes were:

• Assiniboine and Sioux

• Cheyenne River Sioux

• Colville

• Confederated Salish and Kootenai

• Crow

• Oglala Sioux

• Onondaga Nation

• Rosebud Sioux

• Sisseton-Wahpeton Sioux

• Turtle Mountain Tribe

• Winnebago Tribe of Nebraska

At that meeting, tribal representatives voiced concerns that oversnow motorized vehicles,

the grooming of road and trail surfaces, and the movement of people would negatively

impact YNP’s bison population.
CONSULTATION AND COORDINATION

19

The affiliated tribes received copies of the DEIS for review and comment in midSeptember 1999, and were notified of six public hearings on the draft plans in lateSeptember 1999. On October 6, 1999, members of the Assiniboine and Sioux (Fort

Peck), Cheyenne River Sioux, Confederated Salish and Kootenai, Crow, Lac Courte

Oreilles, Nez Perce, Rosebud Sioux, the Winnebago Tribe of Nebraska, and

organizations met with Yellowstone and Grand Teton staff to discuss the Winter Use

Plans as part of fall 1999 government-to-government tribal consultation meetings. The

nine cooperating agencies were notified of this meeting, and some chose to participate.

On April 26, 2000, Yellowstone and Grand Teton staff again met with representatives of

the Confederated Tribes of the Salish and Kootenai, Eastern Shoshone, Nez Perce Tribe,

Oglala Sioux, Prairie Band of the Potawatomi, Rosebud Sioux Tribe, Shoshone-Bannock,

Winnebago Tribe of Nebraska, as part of the Spring 2000 tribal consultation meetings

and provided them with an update regarding the status of the Winter Use Plans/EIS.

The NPS will continue to consult with representatives of affiliated tribes as actions

resulting from this plan are implemented. The goal of consultation is to insure that the

affiliated tribes’ interests and concerns are adequately addressed, as well as to develop

and accomplish future programs in a way that respects the beliefs, traditions, and other

cultural values of the American Indian tribes who have ancestral ties to the area.

State Historic Preservation Offices

In October 1995, a programmatic agreement was developed among the National

Conference of State Historic Preservation Offices (SHPO), the Advisory Council on

Historic Preservation (Council) and the NPS. In accordance with the agreement and

pursuant to Section 106 of the National Historic Preservation Act [16 USC 470(f)],

consultation with the Wyoming, Montana, and Idaho SHPOs and the Council was

initiated in May 1998. The NPS sent copies of the scoping brochure (May 1998) and the

draft preliminary winter use alternatives (December 1998) to the SHPOs and the Council.

In accordance with their request, the NPS continued to consult with the Wyoming,

Montana, and Idaho SHPOs and the Council regarding actions described in the Winter

Use Plans/EIS that may affect cultural resources (Appendix E). The NPS mailed copies

of the Draft EIS to each SHPO and the Council for review and comment. Before

completion of the FEIS, the NPS contacted the SHPOs of all three states directly, and all

offices stated that they had no comments on the DEIS and saw no need for further

consultation.

U.S. Fish and Wildlife Service

The settlement agreement with The Fund for Animals et al. required the NPS to prepare a

Biological Assessment (BA) and request formal consultation with the USFWS pursuant

to Section 7(a)(2) of the ESA, 16 USC 1536(a)(2) and its implementing regulations. To

comply, on February 16, 2000 the NPS requested from the USFWS an updated list of all

federally protected threatened, endangered, proposed, or candidate species that might

occur in the affected area (Appendix D).
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PURPOSE OF AND NEED FOR THE ACTION

20

A BA evaluates the effects of a preferred alternative on species listed under the ESA; it is

not required to evaluate all alternatives to a proposed action. Because winter use is

highly controversial, and the NPS was aware of the potential for considerable post-draft

changes, it elected not to initiate consultation at the time the DEIS was issued. Instead, a

BA was prepared for the FEIS preferred alternative, and subsequently submitted to

USFWS on July 5, 2000.15 Should the USFWS determine that there may be an adverse

impact on any listed species, formal consultation will proceed between the two agencies.

PUBLIC INVOLVEMENT

Scoping

The NPS accepted public scoping comments from April 14 to July 18, 1998. Scoping

brochures were mailed to about 6,000 interested parties, and 12 public meetings were

held throughout the GYA and in Idaho, Montana, and Wyoming. In addition to local

area and regional meetings, The NPS held four national meetings in Salt Lake City,

Denver, Minneapolis, and Washington D.C. About 2,000 comment letters were received

(about 1,200 of these were form letters), from which about 15,000 discrete comments

were obtained. Scoping respondents included businesses; private and nonprofit

organizations; local, state and federal agencies; and the public at large. Comments were

received from 46 states and several foreign countries.

Summary of Public Scoping Comment

Comments received during scoping cover a full range of topics including issues,

concerns, analysis questions, procedural questions, general opinions, and requests.

Comments were sorted into the categories shown in Table 2.

The NPS addressed all comments received in one of two ways: 1) either they were

analyzed in detail through the development of an alternative or as a possible impact of

winter use; or 2) they were not analyzed further based on the rationale presented in

Volume II, Appendix A. The NPS classified comments as major issues or concerns to be

analyzed in detail based on relevance to the decision to be made. The following section,

Major Issues, describes in greater detail those comment categories considered relevant.

Issues or Concerns Not Addressed in the Plans/EIS describes specific types of comments

not carried forward for in-depth analysis, and the rationale for their dismissal.

 

15 Actions taken in accordance with Endangered Species Consultation Handbook: Procedures for Conducting

Consultation and Conference Activities under Section 7 of the Endangered Species Act, March 1998.
PUBLIC INVOLVEMENT

21

Table 2. Summary of comments received during scoping.

General Topic Subtopic Comment

Visitor Use and Access

Developed Facilities Effects on visitor enjoyment during peak use periods when parking

areas, roads, warming huts, and eating facilities are full

Undeveloped

Facilities

Effects on visitor enjoyment during peak use periods, when trails and

other undeveloped facilities are at capacity Facilities

Privatization Effects of privatizing parks’ facilities on the quantity, quality, and

availability of services

User Conflict Visitor’s expectation of quiet, serene, experience or a more social

setting, and the conflicts that can occur when different user groups

overlap

Suitable Ungroomed

Terrain

Adequacy of ungroomed, nonmotorized areas in gentle terrain suitable

for family activities and education outings near population centers

Visitor

Experience

Winter Recreational

Activities

Adequacy of a range of winter visitor experiences defined for the

parks

Visitor Access

Types of Access and

Their Limitations

Access to most locations in the parks is limited to those who can

afford to ride a snowmobile or snowcoach. Concerns include plowing

of roads, segregation of user groups, access for disabled persons,

parks closure in winter, and zone management

Visitor Use Trends

and Carrying

Capacity

Effects of increasing use on parks’ resources, cumulative impacts of

more users and additional uses; the actual or perceived amount of use

versus the parks’ capabilities

Control Mechanisms Management mechanisms that the parks can use to control visitor

numbers, such as raising fees, reservation systems, lottery, season

lengths, daily limits, dispersion techniques

Recreational

Demand

Summer versus

Winter Use

Comparisons

Comparison of the effects of summer versus winter use on visitors,

employees, and the natural resources of the parks

Human Health and Safety

Traffic Safety The safety of visitors and employees traveling through the parks on all

modes of transportation

CDST Concern about the safety of shared use by snowmobiles and

Safety automobiles on the US Highway 89/12/287 corridor

Novice Users Concern about the ability of novice snowmobile riders and skiers to

respond to heavy traffic, high speeds, wildlife on trails, rapidly

changing weather conditions, and varying trail conditions

Health Pollution Effects Effects of snowmachine emissions on the health of employees,

visitors, and local residents
CHAPTER I

PURPOSE OF AND NEED FOR THE ACTION

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General Topic Subtopic Comment

Local Community and Adjacent Lands

Employment The role of public lands and the associated tourist industry on the

economic welfare of local communities, with an emphasis on

employment opportunity

Fiscal Fiscal effects of possible changes in winter use (taxes, wages)

Economic

Effects

Costs Effects of commercial competition on cost of equipment rental,

lodging, food, supplies

Communities Housing, schools, hospitals, police and fire protection, and other

infrastructure

Social Effects Quality of Life Effects on the quality of life in local communities due to use patterns

Social Structure,

Values

Effects on the social structure and values in local communities due to

winter use patterns

Adjacent

Lands

Adjacent Lands Effects of changing winter use patterns within the parks on nearby

national forests and communities

Parks Infrastructure and Operations

Gasoline Storage

Capacity

Limited storage tank capacity: fuel must be brought into the parks in

the fall and stored; increasing demand for gasoline sold in the winter

is exceeding capacity

Waste Storage

Capacity

Storage capacities for garbage and sewage are limited: increased

visitor use is exceeding the capacity of facilities, which must capture

and store wastes over the winter season

Parks Personnel Changes in winter use may alter parks administrative needs for

providing visitor services

Natural Resources

Geothermal

Resources

Geothermal

Resources

Concern about effects on geothermal resources from visitor-wildlife

use, infrastructure, and operations

Particulates Concern about airborne particulate matter exceeding NAAQS limits

Air Quality Visibility Concern about visible air pollution from combustion exhaust,

including machinery, vehicles, and wood burning

Surface Water Effects of oil and gas effluent and airborne pollution from

snowmobiles

Water Quality

Soil Erosion Concern about winter use as a cause of soil erosion, and consequent

impacts on levels of sedimentation and aquatic life

Sound Effects of Noise Effects of high levels of sound on visitors, employees, and wildlife

Effects of Skiers Effects of backcountry skiing on various wildlife species

Effects of

Snowmobiles

Effects of snowmachine use on various wildlife species

Wildlife, Other

than Bison Carrying Capacity Concern about the natural carrying capacity for wildlife, the physical

constraints of the parks’ resources, and how that may relate to winter

use
MAJOR ISSUES

23

General Topic Subtopic Comment

Migration/

Population

Concern about the effect of road grooming on bison migration

from the parks, and how the population is affected as a result

Bison Carrying Capacity Concern about the natural carrying capacity for bison, the

physical constraints of the parks’ resources, and how that may

relate to winter use

Land Use Land Use Effects of parks activities on timber, mining, and hunting

Vegetation Vegetation Effects of winter use on vegetation

Cultural

Resources

Effects on Cultural

Resources

Concern about cultural and historic resources on the parks, and

their status as United Nations Biosphere Reserve or World

Heritage Site

Wilderness Wilderness Concern about the effects of winter use on wilderness

EIS Process

Cooperating

Agencies

Concern about and requests for county involvement in the EIS

process as cooperating agencies

NEPA NEPA process concerns and the effect of NEPA on the

development of NPS policies

Scientific Studies Concerns about the role of scientific studies and data as applied

to the analysis of winter use impacts

Alternatives Many comments suggested alternatives that should be

considered

MAJOR ISSUES

This section summarizes the major issues that relate to the purpose and need for action

for the future of winter use in the three NPS units. These issues parallel the existing

conditions identified in the purpose and need for action. While common concerns exist

among the issues, they are categorized for purposes of analysis and alternative

formulation. Because the decision regarding the future of winter use in the GYA is

programmatic, relevant issues are those that bear on: 1) winter programs that might be

necessary to address existing circumstances and achieve desired conditions; and 2) the

effects of those programs. An issue is defined as a point of contention about the specific

possible environmental effect of a specific management action or program. Generally,

comments on the DEIS about the details of implementing a program are not considered

major issues. Implementation details will be important during future site-specific

analyses under the new plan.

Another opportunity for public involvement is commenting on the DEIS. No new major

issues were identified as a result of public comments on the DEIS. Volume III contains

the analysis of public comments on the DEIS, and response to the comments.

Visitor Use and Access

Various user groups contend that the national parks offer either too much or not enough

of various types of use. Some people are concerned that the parks do not offer an

adequate range of winter experiences and will not be able to respond to future winter
CHAPTER I

PURPOSE OF AND NEED FOR THE ACTION

24

recreation demand. Others suggested that winter experiences should include

dogsledding, off-road motorized play areas, and increases in both groomed motorized

and nonmotorized trails. Other people voiced concerns about too much winter use,

suggesting that YNP close in part or altogether, for the winter season. Because of the

amount of use relative to the available facilities, both ski and snowmobile use sometimes

occurs on the same groomed surface. This adds to the perception of too much use, and

leads to other issues relating to visitor experience and safety. Many people contend that

motorized use has greatly affected opportunities for nonmotorized use in the surrounding

GYA, displacing cross-country skiing to the parks. Another aspect of the issue relates to

the affordability of winter access, and access for disabled, and old and young visitors.

Some argue for increased availability of motorized access (via snowmobile in particular)

to serve these access needs. Another issue is the high cost of winter access to the parks.

Visitor Experience

Expectations for quality winter recreation experiences are different for different user

groups. This raises contention between groups for which quiet and solitude, and clean air

needs conflict with the impacts of snowmobiles, especially when facilities for these

different groups are in close proximity to each other. Skiers are easily affected or

displaced by the sight, sound, and odor of snowmobiles. While skiing generally does not

affect the quality of the snowmobiling experience, there are safety issues associated with

slow traffic on groomed surfaces. In addition the quality of the visitor experience can be

affected by the number of available support facilities (such as parking lots or rest rooms),

the extent to which facilities are crowded, and the availability of information.

Human Health and Safety

Four primary health and safety issues were identified regarding winter visitor use:

• The effect of motorized vehicular emissions and noise on employees who are required to

travel or work in areas with high traffic levels. Visitors may be subjected to some of the

same impacts.

• Speed limits and the frequency of motor vehicle accidents and fatalities, as well as the

number of nighttime collisions involving wildlife that often result in severe injury or

fatality to both animals and people.

• Avalanche hazards.

• Safety problems where different modes of winter transport are co-located or in close

proximity. A primary example is the CDST where wheeled-vehicles and snowmobiles

share the highway right-of-way.

Social and Economic Issues

Many comments reflected the effect of changes in parks management actions on local

communities. Local businesses provide services to visitors near both parks, and many

local economies rely, in part, on revenues from parks visitors in the winter. Concern was

voiced that eliminating oversnow travel and snowmobiles in particular or closing an

entrance to a park during the winter could have a detrimental effect on local economies.

Other commenters stated that concern for parks’ resources should be elevated above

economics.
ISSUES OR CONCERNS NOT ADDRESSED IN THE PLANS/EIS

25

Natural Resources

Impacts of winter use on natural resources revolve around three major issues.

• The impact of groomed surfaces and their use on wildlife: Over the last several years, bison

have been removed from the population because they have migrated from YNP to state and

private lands during the winter. Some people commented on the effect that backcountry

skiing might have on wildlife, particularly the displacement of large ungulates from

important winter range.

• Air quality: The effect of snowmobile emissions on air quality was identified as a concern

with respect to health, natural resources, and aesthetic and wilderness values. For example,

on high snowmobile use days in YNP, the visual evidence and odor of snowmobile exhaust

is apparent in some areas. The effect of hydrocarbons, carbon monoxide, and particulates

emitted by snowmobiles on water quality was also a concern.

• Oversnow vehicle sound: The sound levels of snowmobiles and snowcoaches were raised

as issues with regard to aesthetics and wilderness values. For example, on some days it is

difficult for most visitors to travel to an area in YNP where snowmachines cannot be heard.

For this reason some people question whether the use of snowmobiles and snowcoaches is

appropriate in the national parks. Other people state that the sound of snowmachines has

no impact on their ability to enjoy the parks.

ISSUES OR CONCERNS NOT ADDRESSED IN THE PLANS/EIS

Privatization

Some comments proposed the privatizing of parks’ facilities to alter the quantity, quality,

and availability of services for winter use. Privatization is not within the scope of the

decision to be made in this analysis. Existing park concessions are privately owned and

operated, and they provide a number of services under contract with the NPS.

Concession operations or changes to them are the subject of separate analyses by YNP

and GTNP. Additionally, Congress recently passed new statutory provisions regarding

concessions in parks, and the NPS will issue regulations implementing the new law soon.

Summer/Winter Use Comparisons

Some comments compared summer and winter use levels and autos versus snowmobiles

to show that no problem exists and, winter use should not be limited. The purpose of this

analysis is not to limit use. Rather it is to determine the potential effects of existing and

projected winter use, then to decide what actions to take. Summer recreation entails a

different set of circumstances, issues, and concerns. Therefore, the comparison is outside

the scope of the decision to be made in this analysis.

Wildlife Carrying Capacities

Comments expressed concerns about the carrying capacity of the parks for bison and

other wildlife species. Some commenters feel that knowing the natural carrying capacity

would illuminate the significance of wildlife impacts from winter use. Determining or

setting the carrying capacity for wildlife species, including bison, is a complex effort

outside the scope of this study and the decision to be made. The NPS believes that this

subject is best addressed in the broader context of the Bison Management EIS/Plan. Any

determinations made in the final Bison Management EIS/Plan and decision may have a

bearing on winter use. The planning teams on these two EISs/Plans are coordinating

with each other to the greatest extent possible. It is sufficient for purposes of this
CHAPTER I

PURPOSE OF AND NEED FOR THE ACTION

26

analysis to describe the nature of possible impacts on species of concern for the activities

associated with winter use programs.

Land Use

Some comments expressed concern about the possibility of mining, logging, or hunting

within parks boundaries. Such actions are not part of the proposal at hand, and other than

hunting on the Parkway, these activities are not permitted within these parks. As such,

these concerns are outside the scope of analysis.

Economic Effects: Costs

Some comments expressed concern about commercial competition by national parks

concessioners on lodging, equipment rentals, food, supplies, or other items supporting

winter recreational use. This concern is outside the scope of the decision to be made.

This analysis and resulting decision does not bear on concession operations. See

Privatization, above.

EIS Process

A number of people gave their perceptions of various portions of the EIS process. Such

process concerns are not considered or addressed as issues, and except for the following

discussion are dismissed without further analysis.

Cooperating Agencies

Some comments opposed and others favored county and state involvement, including

tribal governments, as cooperating agencies in the EIS. NEPA allows for the inclusion of

other government agencies — federal, state, and local — as cooperating agencies based

on special expertise with respect to any environmental issue, or jurisdiction in law (40

CFR §1508.5, §1508.15, §1508.26).

NEPA and NPS Policy

Some comments expressed concern regarding the influence of NEPA on the development

of national park policy. This is dismissed since NEPA, a procedural law, is required to

assess the potential environmental impacts of any federal proposed action, including

programmatic management plans such as this. NEPA is a decision-making tool that

requires public involvement, attention to public issues, and development of alternatives

that address the purpose and need for action. The decision maker or official, who will

make a decision based on NEPA analysis, has discretion to decide the scope of analysis.

The decision maker can orient the analysis to consider only alternatives that conform to

existing policy, or broaden the scope to investigate alternatives for situations in which

existing policy is inadequate. The Plans/EIS focus on alternatives within legal and

regulatory boundaries and national policy direction.

Scientific Methods and Data

Some concerns addressed the use of scientific methods and data to determine or interpret

the effects of winter recreational use. The analysis documented in this EIS is
OTHER PLANS AND ENVIRONMENTAL ANALYSES

27

programmatic. That is, it evaluates the possible general effects of the integrated winter

recreation program in three national parks. Conversely a project analysis evaluates the

potential site-specific effects of a proposed action. The scientific analyses and associated

data needs are different for programmatic and site-specific levels of NEPA

documentation. Programmatic assessments do not require detailed, site-specific data.

Methods and data need to be sufficient to determine if the alternatives meet the purpose

and need for action, and are within the scope of the decision to be made. This EIS uses

the best available information, most definitive studies, and most applicable research.

Suggested Alternatives

A number of comment letters included alternative suggestions. Many of these

suggestions were incorporated into the alternatives considered in detail in this EIS, while

other suggestions were not. Alternatives considered but dismissed from detailed analysis

are presented at the end of the Alternatives section in Chapter II. The cooperating

agencies participated in a work session at the beginning of the alternative formulation

process. The suggestions for alternatives or features to be considered were analyzed, and

about 68% of the ideas were incorporated into the range of alternatives for the DEIS.

The analysis of workshop ideas was published in DEIS Volume II, Appendix A.

OTHER PLANS AND ENVIRONMENTAL ANALYSES

There are other ongoing planning efforts that relate to some elements of this EIS/plan.

As other plans are approved, they can incorporate relevant portions of the winter use

plans. In reference to the previous discussion of the purpose of and need for action, some

comments or possible issues are more appropriately dealt with in other plans or

assessments. Related planning efforts include:

• The Draft Commercial Services Plan for YNP is scheduled for completion in 2000.

• The Commercial Services Plan for GTNP is in final draft and under review by the park

superintendent.

• Grand Teton has recognized the importance of developing a comprehensive transportation

plan, including winter transportation services. Prompted by the completion of a Jackson

Hole transportation plan, GTNP has initiated a study of transportation needs and a data

collection effort to determine how it can integrate with local plans.

• Yellowstone has taken a comprehensive look at its roads and transportation systems

through several reports and studies. YNP is also a partner in the GYA Clean Cities

Initiative.

• The Bison Management Plan for the State of Montana and YNP is scheduled for

completion in summer 2000.

In the Bison Management EIS/Plan, alternative 2 would require closing several road

segments to grooming in the winter or evaluating road segments for closure. The road

segment closures analyzed under alternative 2 are from Mammoth to Norris, Norris to

Madison, Madison south to Fountain Flats, and Madison west to West Yellowstone.

Alternative 3 calls for the research of effects of road grooming on bison. If research

indicates bison use particular road segments, some road segments could be left

ungroomed to help keep more bison inside the park.

Alternative 5 calls for plowing routes to bison capture facilities throughout the winter,

including routes from West Yellowstone to Madison, Madison south to Fountain Flats,

Madison to Norris, Norris to Canyon, and Canyon to Pelican Valley. These capture

facilities would be operated from three to five years.
CHAPTER I

PURPOSE OF AND NEED FOR THE ACTION

28

Alternative 6 consists of two phases. Phase 1 requires that the road from West

Yellowstone to a capture facility at Seven-Mile Bridge be plowed to pavement, thus

eliminating oversnow travel. The Seven-Mile Bridge facility was assumed to operate

for at least 10 years. Phase 2 would require a similar plowing regime to the one

described in alternative 5. Phase 2 would be operational for two to three years.

The modified preferred alternative would have no effect on winter road operations in

YNP.

Implementation of certain elements of the Winter Use Plans for YNP and GTNP and the

Parkway could be deferred if the road plowing or closures analyzed in alternative 2, 5

or 6 of the Draft Environmental Impact Statement for the Interagency Bison

Management Plan for the State of Montana and YNP are selected.

• On October 27, 1997, the United States District Court in Washington, D.C. approved a

settlement agreement that called for the NPS to prepare an environmental assessment

evaluating the closure of a winter road segment in YNP. The agreement settled a lawsuit

filed by The Fund for Animals and others, which asserted that the NPS had failed to

evaluate the effects of trail grooming in the parks on wildlife and other park resources. The

Environmental Assessment — Temporary Closure of a Winter Road in YNP was published

in November 1997. The FONSI for the environmental assessment states that the decision

whether to close a road segment will be made by December 1, 2000. The decision was

deferred because baseline information on wildlife movements needs to be gathered before

evaluating the effects of closing the road segment. A one-year grace period before

implementation would delay a road closure, if necessary, until the winter of 2001-2002.

The FONSI also states that the NPS may modify or change this decision as a consequence

of other planning processes underway or intended, such as the Winter Use Plans for YNP,

GTNP, and the Parkway.
OTHER PLANS AND ENVIRONMENTAL ANALYSES

29
30

CHAPTER II

ALTERNATIVES INCLUDING THE PROPOSED ACTION

INTRODUCTION

This chapter presents detailed descriptions of alternatives, including the preferred

alternative, that meets the purpose of and need for action. These alternatives present a

clear basis of choice, while sharply defining different actions that are intended to address

the major issues described in Chapter I. The alternatives were formulated purposefully to

provide a range of different actions and strategies, so that the effects of actions could

reasonably be determined and compared. Each alternative proposes actions that optimize

one or more aspects of the purpose and need for action.

In addition to describing alternatives considered in detail, this chapter briefly discusses

how alternatives were formulated, and lists alternatives that were considered but

eliminated from detailed analysis. In accordance with National Environmental Policy

Act (NEPA), alternatives and their effects are presented in a comparative form, and

mitigation measures not already included in alternatives are described.

FORMULATION OF ALTERNATIVES

The alternatives for the Winter Use Plans and Environmental Impact Statement for

Yellowstone National Park (YNP), Grand Teton National Park (GTNP) and the John D.

Rockefeller, Jr., Memorial Parkway (the Parkway) were formulated in response to the

major issues and concerns raised through public and internal scoping. In addition to the

scoping process, the National Park Service (NPS) and the cooperating agencies met in

Idaho Falls, Idaho in October 1998 to formulate initial concepts for alternatives. Twentyfive participants and about 10 observers attended the 3-day workshop. Later, similar

workshops were held with park staffs in both parks. In total, over 35 alternative concepts

were generated from the 3 workshops. For a complete discussion of the concepts

generated during the workshops see Appendix A.

The NPS planning team evaluated the concepts in terms of their responsiveness to the

major issues and concerns, the decision to be made, and the purpose and need for the

Winter Use Plans. The concepts were also evaluated against their adherence to current

law, park management guidelines, and NPS mandates and policies. Lastly, each concept

was evaluated for its economic and technical feasibility. The concepts that best met the

above criteria were packaged into the range of alternatives discussed below. Each
ALTERNATIVE DESCRIPTION

31

alternative proposed considers a different means of achieving the desired condition of the

parks in the winter while minimizing impacts to park resources.

ALTERNATIVE DESCRIPTION

The conceptual basis for alternatives is varying the mix of winter recreation opportunities

and facilities to meet the need for action or address major issues. Each alternative

consists of up to five components: alternative actions, map, management zone

descriptions, mitigation, and monitoring. All components are essential for a

comprehensive understanding of each alternative. Table 11 summarizes the actions for

each alternative by topic, and the components are summarized below.

Alternative Actions

The actions and assumptions common to all alternatives for the three parks are listed

first, followed by actions common to all alternatives, but specific to each park.

Following common actions, each alternative is explained in terms of its conceptual basis,

the issues it responds to, and the specific programmatic actions, or features, that would be

proposed for each park. Alternative maps show recreational zones and opportunities for

each park, creating a picture of how the actions would be applied geographically.

Management Zones

For each alternative, the parks are divided into management zones. Management zones

are defined as shown in Table 3 using the following characteristics.

• Desired resource condition or character

• Desired visitor experience

• Appropriate activities and facilities

Management zone definitions do not change by alternative, but their allocation to

locations in the parks does change. The purpose of the management zone allocation is to

detail the range of visitor experiences that would be provided, the resource parameters

necessary to provide that experience, and to describe where in the parks each type of

experience would occur. Consequently, each alternative description describes a different

mix of visitor experiences and resource conditions for the parks. This approach considers

and analyzes a diversity of appropriate experiences and underlying resource conditions,

and helps structure future carrying capacity analyses.
Table 3. Management Prescriptions (Zones), Yellowstone and Grand Teton National Parks and the John D. Rockefeller, Jr., Memorial Parkway Winter Use Plan

Management

Prescriptions

(Zones)

1

Destination or

Support Area

2

Plowed Road

(wheeled vehicles)

3

Groomed Motorized Route

(clean quiet travel)

4

Groomed Motorized

Route

5

Groomed Motorized Trail

(clean quiet travel)

6

Groomed

Motorized Trail

7

Ungroomed Motorized Trail

or Area

(clean quiet travel)

8

Groomed Nonmotorized

Trail

9

Ungroomed Nonmotorized

Trail or Area

10

Backcountry

Nonmotorized Area

11

Sensitive Resource Area

(no winter use)

Resource

Condition or

Character

• Minimally to

highly developed

hubs of activity

• Facilities and signs

of human activity

obvious, but

natural elements

also present

• Moderate to high

management

and/or

modification of

resources to

accommodate

operational needs,

resource

protection, visitor

enjoyment, and

safety

• As small as

possible while still

providing essential

services

• Visitor use may

compromise

natural resource

values

• As narrow as possible to

protect resources, but wide

enough to accommodate

safety pullouts, overlooks,

and trailhead areas

• Moderate to high

management and/or

modification of resources

to accommodate

operational needs,

resource protection, visitor

enjoyment, and safety

• Good to excellent air

quality

• Visitor use may

compromise resource

values

• Smooth groomed snow

surface

• Generally gentle terrain

• Good to excellent air

quality

• As narrow as possible to

protect resources, but wide

enough to accommodate

safety pullouts, overlooks,

and trailhead areas

• Moderate to high

management and/or

modification of resources

to accommodate

operational needs,

resource protection, visitor

enjoyment, and safety

• Visitor use may

compromise resource

values

• Same as 3 but with

higher sound and

vehicle exhaust

levels;

• Visitor use may

compromise

resource values

• Narrower, groomed but less

maintained snow surface

• Gentle to moderate terrain

• Vehicles must meet sound

and emission standards

• Generally good to excellent

air quality

• Sound levels intermittent,

low to moderate

• As narrow as possible to

protect resources, but wide

enough to accommodate

pullouts, overlooks

trailheads, trailhead areas

• Minimal modification of

resources to accommodate

operational needs, resource

protection, visitor

enjoyment, and safety

• Visitor use may compromise

resource values

• Same as 5 but

with higher

sound and

vehicle exhaust

levels;

• Visitor use may

compromise

resource values

• Ungroomed snow surface

• Marked except for frozen

water surfaces

• Gentle to moderate terrain

• Vehicles must meet sound

and emission standards

• Generally good to excellent

air quality

• Sound levels intermittent,

low to moderate

• Wide enough to

accommodate existing road

corridor, pullouts, overlooks

trailheads, trailhead areas

• Low to moderate

modification of resources to

accommodate operational

needs, resource protection,

visitor enjoyment, and

safety

• Visitor use may compromise

resource values

• Smooth groomed snow

surface

• Marked and signed

• Generally gentle terrain

• Creates predictable patterns

of winter use and confines

resource impacts to narrow

corridors

• Good to excellent air

quality

• Minimal modification of

resources to accommodate

operational needs, resource

protection, visitor

enjoyments, and safety

• Visitor use may compromise

resource values

• Ungroomed snow surface

• Marked or unmarked

• Gentle to steep terrain

• Creates fairly predictable

patterns of winter use and

confines resource impacts

to relatively narrow

corridors

• Good to excellent air

quality

• Minimal modification of

resources to accommodate

operational needs,

resource protection, visitor

enjoyments, and safety

• Visitor use may

compromise resource

values

• Appears natural and

untouched by humans

• Gentle to steep terrain

• Good to excellent air

quality

• Little to no evidence of

visitor impacts

• Little to no modification of

resources to accommodate

operational needs,

resource protection, visitor

enjoyments, and safety

• Visitor use may

compromise resource

values

• Appears natural and

untouched by humans

• Gentle to steep terrain

• Good to excellent air

quality

• Natural and/or cultural

resource values so

vulnerable that winter

visitor use is not

permitted

Visitor

Experience

• Facilities

convenient and

blended with

adjacent resources

• Many opportunities

for social

interaction

• High sound levels

possible

• High probability of

encountering

other visitors and

NPS staff

• Destinations and natural

attractions of high interest

• High probability of

encountering other

visitors

• Provides a sense of being

in a natural park

environment

• Visitor experience mostly

visual

• Occasional quiet and

solitude

• Commercial or residential

traffic on some stretches

• Intermittent low to

moderate sound associated

with vehicular travel

expected

• Destinations and natural

attractions of high interest

• Provides a sense of being

in a natural park

environment

• High probability of

encountering other

visitors

• Solitude occasionally

possible, but not expected

• Limited opportunities for

challenge and adventure

• Few outdoor skills needed

• Some low-level sound

associated with travel

expected

• Same as 3 but

opportunities for

quiet not expected,

Sight and smell of

vehicle exhaust

expected

• Natural attractions of high

interest

• Moderate probability of

encountering other visitors

• Chance to view the natural

environment important

• Solitude occasionally

possible, but not expected

• Some outdoor skills

necessary

• Some opportunities for

challenge and adventure

• Relatively quiet; sight and

smell of vehicle exhaust not

expected

• Same as 5 but

 opportunities for

quiet not

expected,

• Sight and smell of

vehicle exhaust

expected

• Natural attractions of high

interest

• Moderate probability of

encountering other visitors

• Chance to view the natural

environment important

• Solitude occasionally

possible, but not expected

• Moderate outdoor skills

necessary

• Moderate opportunities for

challenge and adventure

• Relatively quiet; sight and

smell of vehicle exhaust not

expected

• Provides a sense of

immersion in a generally

natural landscape

• Natural attractions of high

interest

• High probability of

encountering other users

• Solitude occasionally

possible, but not expected

• Provides some sense of

adventure

• Few outdoor skills needed

• Quiet desirable but not

essential for visitor

enjoyment

• Provides a sense of

immersion in a generally

natural landscape

• Natural attractions of high

interest

• Moderate probability of

encountering other users;

probability increases near

destination areas

• Moderate opportunities for

solitude

• Feels somewhat distant

from most comforts,

conveniences, and

facilities

• Generally requires a

commitment to timeconsuming and physically

and mentally exerting

activities

• Provides opportunities for

adventure and physical

challenge

• Outdoor skills needed

• Provides a strong sense of

immersion in a very

natural landscape

• Natural quiet expected

• Low probability of

encountering other users;

good opportunities for

solitude

• Provides strong sense of

remoteness

• Requires a commitment to

time-consuming and

physically and mentally

exerting activities

• Good opportunities for

adventure and physical

challenge

• Outdoor skills such as

route finding, avalanche

hazard forecasting, and

survival knowledge

necessary

• None

Appropriate

Activities

and

Facilities

• Visitor centers

• Warming huts

• Overnight lodging

• Gas stations

• Food services

• Staging areas

• Administrative

facilities

• Structured

interpretive

programs

• Wheeled vehicular travel

only

• Paved and unpaved

roadways, signs, barriers

• Interpretive media and

display

• Utilities

• Scenic overlooks,

restrooms, trailhead areas,

pullouts

• Predominantly oversnow

vehicular travel; some

non-vehicular travel

• Oversnow roads, signs,

barriers

• Interpretive media,

programs and displays

• Utilities

• Scenic overlooks,

restrooms, trailhead areas,

pullouts

• Same as 3 • Predominantly oversnow

vehicular travel; some nonvehicular travel

• Oversnow trails, signs,

barriers

• Utilities, scenic overlooks,

trailhead areas, restrooms

• Same as 5 • Predominantly oversnow

vehicular travel; some nonvehicular travel

• Oversnow roads, signs,

barriers

• Interpretive displays

• Utilities, restrooms, scenic

overlooks, trailhead areas

• Nonmotorized activities

only, such as skiing and

snowshoeing

• Oversnow trails, markers,

signs, barriers

• Interpretive media

• Scenic overlooks, trailheads

• Nonmotorized activities

only, such as skiing and

snowshoeing

• Signs or other route

markers

• Nonmotorized activities

only, such as skiing and

snowshoeing

• No facilities

• Limited resource

management activities

• No visitor activities or

facilities
ALTERNATIVE DESCRIPTION

33
Table 4. Monitoring Indicators by Management Zone, Yellowstone and Grand Teton National Parks and the John D. Rockefeller, Jr., Memorial Parkway Winter Use Plan

Manageme

nt

Zone 

1

Destination or

Support Area

2

Plowed road

3

Groomed Motorized Route

Clean Quiet Travel

4

Groomed Motorized Route

5

Groomed Motorized

Trail

Clean and Quiet

6

Groomed Motorized

Trail

7

Ungroomed

Motorized Trail

8

Groomed Nonmotorized Trail

9

Ungroomed Nonmotorized Trail or

Area

10

Backcountry Nonmotorized Trail or

Area

11

Sensitive Resource

Area

Resource

Value

Indicators

Air Quality

(Including

employee

and visitor

health)

• Visibility

• Odor

• Park workers

and visitors

exposure to CO,

particulate

matter and

VOC’s

• Visibility

• Odor

• Park workers and

visitors exposure

to CO, particulate

matter and

VOC’s

• Visibility

• Odor

• Park workers and visitors

exposure to CO, particulate

matter and VOC’s

• Develop exposure

measurements for snowcoaches

• Visibility

• Odor

• Park workers and visitors exposure

to CO, particulate matter and

VOC’s

• Visibility

• Odor

• Park workers and visitors

exposure to CO, particulate

matter and VOC’s

• Visibility

• Odor

• Park workers and

visitors exposure to

CO, particulate matter

and VOC’s

• Visibility

• Odor

• Park workers and

visitors exposure to CO,

particulate matter and

VOC’s

• Visibility

• Odor

• Visibility

• Odor

• Visibility

• Odor

• Visibility

• Odor

Wildlife • Bird and

mammal

habituation:

effectiveness of

garbage facilities

• Harassment of

ungulates

• Vehicle caused

wildlife fatalities

• Displacement/

fragmentation

(trapped in road

corridor)

• Harassment

• Bison

movements on

plowed surfaces

• Harassment/ ungulates

• Carnivore and snowshoe track

surveys

• Bison movements on groomed

surfaces

• Harassment/ ungulates

• Carnivore and snowshoe track

surveys

• Bison movements on groomed

surfaces

• Harassment/ ungulates

• Carnivore and snowshoe track

surveys

• Bison movements on groomed

surfaces

• Habitat displacement/stress

due to sound or vehicle

movements

• Harassment/ ungulates

• Carnivore and

snowshoe track surveys

• Bison movements on

groomed surfaces

• Habitat

displacement/stress

due to sound or vehicle

movements

• Harassment/ ungulates

• Carnivore and

snowshoe track surveys

• Habitat

displacement/stress due

to sound or vehicle

movements

• Harassment/

ungulates

• Habitat avoidance or

displacement/ungulate

s

• Carnivore and

snowshoe track

surveys

• Harassment/ ungulates

• Habitat avoidance or

displacement/ungulates

/

eagles/swans

• Human/bear conflict

during pre-denning and

post denning period

• Harassment/

ungulates

• Habitat avoidance or

displacement/ungulate

s/

eagles/swans/wolverin

es

• Human/bear conflict

during pre-denning

and post denning

period

• Success of closure

Sound • Distance and

time human

caused sound is

audible

• Distance and

time human

caused sound is

audible

• Distance and time human

caused sound is audible

• Distance and time human caused

sound is audible

• Distance and time human

caused sound is audible

• Distance and time

human caused sound is

audible

• Distance and time

human caused sound is

audible

• Distance and time

human caused sound

is audible

• Distance and time

human caused sound is

audible

• Distance and time

human caused sound

is audible

• Success of closure

Water/

Snowpack

• Surface water

sampling of pH,

Hydrogen,

Ammonium,

Calcium,

Sulfate, Nitrate,

VOC’s

• Effects on

roadside

vegetation

• Success of closure

Geotherma

l Features

• Human caused

damage to

geothermal

areas

• Success of closure

Safety • Automobile

incidents

• Snowmobile/ snowcoach

incidents

• Wildlife conflicts

• Visitor conflicts

• Snowmobile/ snowcoach incidents

• Wildlife conflicts

• Visitor conflicts

• Snowmobile incidents

• Wildlife conflicts

• Visitor conflicts

• Visitor conflicts

• Search and rescue

• Wildlife conflicts

• Visitor conflicts

• Search and rescue

• Wildlife conflicts

• Visitor conflicts

• Search and rescue

• Wildlife conflicts

• Visitor conflicts

• Search and rescue

• Wildlife conflicts

• Search and rescue

• Motorized tresspass

• Wildlife conflicts

• Motorized and nonmotorized tresspass

Visitor

Experience

• Waiting lines

• Perceptions of

crowding

attraction sites

• Access to

information

• Parking

• Affordability

• Smoothness of

groomed surface

• Encounter rates

• Access to

information

• Visitor

satisfaction with

opportunities to

experience park

values (wildlife

viewing, scenery

and clean air)

• Smoothness of groomed surface

• Encounter rates

• Access to information

• Visitor satisfaction with

opportunities to experience

park values (wildlife viewing,

scenery and clean air, quiet and

solitude)

• Smoothness of groomed surface

• Encounter rates

• Access to information

• Visitor satisfaction with

opportunities to experience park

values (wildlife viewing, scenery

and clean air, quiet and solitude)

• Smoothness of groomed

surface

• Encounter rates

• Access to information

• Visitor satisfaction with

opportunities to experience

park values (wildlife viewing,

scenery and clean air, quiet and

solitude)

• Encounter rates

• Access to information

• Visitor satisfaction with

opportunities to

experience park values

(wildlife viewing,

scenery and clean air,

quiet and solitude)

• Smoothness of groomed

surface

• Encounter rates

• Access to information

• Visitor satisfaction with

opportunities to

experience park values

(wildlife viewing,

scenery and clean air,

quiet and solitude)

• Encounter rates

• Access to information

• Visitor satisfaction

with opportunities to

experience park values

(wildlife viewing,

scenery and clean air,

quiet and solitude)

• Encounter rates

• Access to information

• Visitor satisfaction with

opportunities to

experience park values

(wildlife viewing,

scenery and clean air,

quiet and solitude)

• Encounter rates

• Visitor satisfaction

with opportunities to

experience park values

(wildlife viewing,

scenery and clean air,

quiet and solitude)

• Success of closure
ALTERNATIVE DESCRIPTION

35
Table 5. Adaptive Management Indicators by Management Zones, Yellowstone and Grand Teton National Parks and the John D. Rockefeller, Jr., Memorial Parkway Winter Use Plan

Management

Prescriptions

(Zones)

1

Destination or Support

Area

2

Plowed Road

(wheeled vehicles)

3

Groomed Motorized

Route

(clean quiet travel)

4

Groomed Motorized Route

5

Groomed Motorized Trail

(clean quiet travel)

6

Groomed Motorized Trail

7

Ungroomed Motorized

Trail or Area

(clean quiet travel)

8

Groomed Nonmotorized

Trail

9

Ungroomed

Nonmotorized Trail or

Area

10

Backcountry

Nonmotorized Area

11

Sensitive Resource Area

(no winter use)

Air Quality • Odor

• Visibility

• Odor

• Visibility

• Odor

• Visibility

• Odor

• Visibility

• Odor

• Visibility

• Odor

• Visibility

• Odor

• Visibility

• Odor

• Visibility

• Odor

• Visibility

• Odor

• Visibility

• Visibility

Wildlife • Vehicles cause wildlife

mortality

• Bison movements on

plowed roads

• Wildlife harassment or

displacement due to

vehicle sound or

movement

• Wildlife trapped by snow

berms in road corridor

• Wildlife mortalities

caused by oversnow

vehicles.

• Wildlife harassment or

displacement due to

vehicle sound or

movement

• Bison use of groomed

surfaces

• Lynx habitat

effectiveness

• Wildlife mortalities

caused by oversnow

vehicles.

• Wildlife harassment or

displacement due to

vehicle sound or

movement

• Bison use of groomed

surfaces

• Lynx habitat effectiveness

• Wildlife harassment or

displacement due to

vehicle sound or

movement

• Bison use of groomed

surfaces

• Lynx habitat effectiveness

• Wildlife harassment or

displacement due to

vehicle sound or

movement

• Bison use of groomed

surfaces

• Lynx habitat effectiveness

• Wildlife harassment or

displacement due to

vehicle sound or

movement

• Lynx habitat effectiveness

• Wildlife harassment or

displacement due to

visitor activity or

movement

• Lynx habitat effectiveness

• Wildlife harassment or

displacement due to

visitor activity or

movement

• Lynx habitat effectiveness

• Human bear conflicts

during pre and post

denning periods.

• Wildlife harassment or

displacement due to

visitor activity or

movement

• Lynx habitat effectiveness

• Human bear conflicts

during pre and post

denning periods.

• Wildlife harassment or

displacement due to

visitor activity or

movement

• Lynx habitat effectiveness

• Human bear conflicts

during pre and post

denning periods.

Sound • Distance and time

human caused sound is

audible

• Distance and time

human caused sound is

audible

• Distance and time

human caused sound is

audible

• Distance and time

human caused sound is

audible

• Distance and time

human caused sound is

audible

• Distance and time

human caused sound is

audible

• Distance and time

human caused sound is

audible

• Distance and time

human caused sound is

audible

• Distance and time

human caused sound is

audible

• Distance and time

human caused sound is

audible

Visitor

Experience

• Perceptions of crowding

• Visitor satisfaction with

opportunities to

experience park values

and opportunities to view

wildlife, scenery, and

experience clean air and

solitude.

• Perceptions of crowding

• Visitor satisfaction with

opportunities to

experience park values

and opportunities to view

wildlife, scenery, and

experience clean air and

solitude.

• Perceptions of crowding

• Smoothness of groomed

surface

• Visitor satisfaction with

opportunities to

experience park values

and opportunities to view

wildlife, scenery, and

experience clean air and

solitude.

• Perceptions of crowding

• Smoothness of groomed

surface

• Visitor satisfaction with

opportunities to

experience park values

and opportunities to view

wildlife, scenery, and

experience clean air and

solitude.

• Perceptions of crowding

• Smoothness of groomed

surface

• Visitor satisfaction with

opportunities to

experience park values

and opportunities to

view wildlife, scenery,

and experience clean air

and solitude.

• Perceptions of crowding

• Smoothness of groomed

surface

• Visitor satisfaction with

opportunities to

experience park values

and opportunities to view

wildlife, scenery, and

experience clean air and

solitude.

• Perceptions of crowding

• Visitor satisfaction with

opportunities to experience

park values and

opportunities to view

wildlife, scenery, and

experience clean air and

solitude.

• Perceptions of crowding

• Visitor satisfaction with

opportunities to

experience park values

and opportunities to view

wildlife, scenery, and

experience clean air and

solitude.

• Perceptions of crowding

• Visitor satisfaction with

opportunities to

experience park values

and opportunities to view

wildlife, scenery, and

experience clean air and

solitude.

• Perceptions of crowding

• Visitor satisfaction with

opportunities to

experience park values

and opportunities to view

wildlife, scenery, and

experience clean air and

solitude.
ALTERNATIVE DESCRIPTION

37
CHAPTER II

ALTERNATIVES INCLUDING THE PROPOSED ACTION

38

Monitoring and Adaptive Management

Table 4 summarizes specific indicators for monitoring natural resources and visitor

experience in each zone. These indicators would be monitored to ensure protection of

natural resources and park values and evaluate management success.

Alternatives B, G, and E include adaptive management provisions. Table 5 describes

indicators and standards for adaptive management. Appendix I includes a complete

listing of monitoring and adaptive management indicators, standards and potential

management actions.

Mitigation

As with alternative actions, mitigation measures represent choices for the decision maker

to incorporate based on consideration of the issues. Mitigation measures should flow

logically from potential impacts disclosed in this environmental impact statement (EIS).

They may involve minimizing impacts by limiting the degree or magnitude of the action,

reducing or eliminating the effect over time by preservation and maintenance, or by

avoiding the impact altogether. Proposed mitigation measures follow the alternative

descriptions.

ALTERNATIVES

Actions and Assumptions Common to All Alternatives

• For all alternatives the NPS would determine visitor use capacities based on studies that set

indicators and standards for desired visitor experiences and resource conditions. The NPS

would monitor indicators to maintain the conditions for each management prescription. If

necessary, techniques such as reservations, permits, and differential fees would be

implemented. See zone descriptions, monitoring table, and Appendix H (Recreation

Carrying Capacity).

• Unless otherwise noted, the parks would implement all actions the winter following the

Record of Decision (ROD) for the winter use plans and EIS. The ROD would be signed no

sooner than 30 days after the release of the Final Environmental Impact Statement (FEIS).

• If it can be demonstrated sufficiently for NPS to determine that a selected alternative

feature substantially affects a concession operation prior to the expiration of its contract,

the action will be implemented through negotiation or when a new contract is awarded.

• Several actions include possible road closures depending on the results of scientific studies.

None of the actions preclude other closures for safety, resource protection, or other reasons

as identified in 36 CFR 1.5 or 2.18.

• For the purposes of these alternatives, the following definitions are consistent throughout:

Oversnow motor vehicles: self-propelled vehicles intended for travel on snow, driven by

a track or tracks in contact with the snow that may be steered by skis or tracks in

contact with the snow. This term includes both snowmobiles and snowcoaches.

Snowmobiles: self-propelled vehicles intended for travel on snow, having a curb weight

of not more than 1,000 pounds (450kg), driven by a track or tracks in contact with the

snow, which may be steered by a ski or skis in contact with the snow.

Snowplanes: self-propelled vehicles intended for oversnow travel, having a weight of not

more than 1,000 pounds (450kg) mounted on skis in contact with the snow, and driven

by a pusher-propeller.

Snowcoaches: self-propelled, mass transit vehicles intended for travel on snow, having a

curb weight of over 1,000 pounds (450kg), driven by a track or tracks and steered by

skis or tracks, having a capacity of at least 8 passengers.
ALTERNATIVES

39

• At present no Environmental Protection Agency (EPA) standards exist for off-road

vehicles. If the EPA adopts more stringent standards or measurement methods for vehicle

emissions and sound levels than those identified in this document, the more stringent

standards or methods would be required for off-road vehicles in the parks.

• The alternatives call for the use of sand, or an equally environmentally neutral substance,

for traction on all plowed winter roads. No salts would be used. Before spring opening,

sand removal operations would continue on all plowed park roads.

• Investigate and implement options to reduce the palatability and accessibility to wildlife of

the hydraulic fluid used in snow groomers.

• When snow depth warrants and at periodic intervals, routine plowing operations would

include laying back roadside snowbanks that could be a barrier to wildlife exiting the road

corridor.

• All alternatives would continue to implement transition and action plans for accessibility

and support the philosophy of universal access in the parks. The NPS would make

reasonable efforts to ensure accessibility to buildings, facilities, programs, and services.

The NPS would develop strategies to ensure that new and renovated facilities, programs

and services (including those provided by concessionaires) are designed, constructed, or

offered in conformance with applicable policies, rules, regulations, and standards

(including but not limited to the Architectural Barriers Act of 1968; the Americans with

Disabilities Act of 1990 (ADA): the Uniform Federal Accessibility Standards of 1984

(UFAS); and the Guidelines for Outdoor Developed Areas of 1999).

Architectural and Site Access and Programmatic Access: The NPS will evaluate existing

buildings and existing and new programs, activities, and services (including

telecommunications and media) to determine current accessibility and usability by

disabled winter visitors. Action plans to remove barriers would be developed.

• Backcountry nonmotorized use would continue to be allowed throughout the parks except

where designated otherwise (see Figures 3, 5, 6, 8, and 14, Zone 11 or area of designated

trail use).

• The phrase gateway communities refers to the towns of Jackson and Cody, Wyoming, and

Gardiner and West Yellowstone, Montana only.

Actions Common to all Yellowstone Alternatives

• In Yellowstone, the NPS would continue to plow Highway 191 and the road from

Mammoth to Tower and Tower to the Northeast Entrance (Cooke City) throughout the

winter.

• A designated route for nonmotorized recreation is defined as a marked or otherwise

indicated oversnow travel way.

• Grand Canyon of the Yellowstone and the McMinn Bench bighorn sheep area would

continue to be closed to winter use.

• Winter garbage storage facilities that are wildlife-proof would be constructed in the Old

Faithful, Grant, Lake, and Canyon areas.

Actions Common to all Grand Teton and Parkway Alternatives

• In Grand Teton and the Parkway, the following roadways would continue to be plowed:

Highway 26/89/287 from the south boundary of the park to Moran

Highway 89/287 from Moran to Colter Bay

Highway 26/287 from Moran to the eastern park boundary

Teton Park Road from Moose Junction to Taggart Lake Trailhead, and from Jackson

Lake Junction to Signal Mountain Lodge; from Highway 89/287 along the Pacific

Creek road to the park boundary; from Kelly to the eastern park boundary; from Gros

Ventre Junction to Kelly to Mailbox Corner; and the road to the eastern park boundary

at Ditch Creek.

• Current winter closures would remain in effect on the Snake River floodplain, the Buffalo

Fork River floodplain, the Uhl Hill area, Willow Flats, Kelly Hill, and Static Peak.
CHAPTER II

ALTERNATIVES INCLUDING THE PROPOSED ACTION

40

• Reasonable and direct access to adjacent public and private lands, or to privately owned

lands within the park with permitted or historical motorized access, will continue via paved

and plowed routes or via oversnow routes from GTNP.

Alternative A—No Action

This alternative reflects current use and management practices in the parks and meets the

requirement for including a no action alternative in an EIS.16 Alternative A is a baseline for

analysis and reflects existing conditions. Other alternatives are intended to improve the existing

condition in one or more major issue areas. Issues associated with alternative A include visitor

access difficulties, visitor experience conflicts, unsafe conditions, and resource impacts (see

Existing Condition and Major Issues in Chapter I). Figure 2. Alternative A for YNP, and

Figure 9. Alternative A for GTNP and the Parkway show current management in the

parks.

Actions Common to All Three Park Units

• The oversnow speed limit is 45 mph (miles per hour) throughout the parks except for the

segment from Moran to Flagg Ranch, which is 35 mph.

• Bio-based fuels and lubricants are used by the NPS and are available for purchase in

gateway communities.

• Current Code of Federal Regulations (36 CFR 2.18) requires that snowmobiles within the

parks operate at or below 78 decibels as measured on the A-weighted scale at 50 feet at full

throttle.

• The 1999 Interagency Winter Use Assessment shows relationships and cooperative

programs for winter use in the Greater Yellowstone Area (GYA). NPS visitor contacts are

provided at visitor centers in West Yellowstone and Jackson Hole.

Actions for Yellowstone National Park

• The following road segments represent about 180 miles of groomed road and are open to

oversnow motorized vehicle travel from mid-December to mid-March:

 

16 CEQ 40 Most Asked Questions, question number 3. Where an existing program is being evaluated, “no

action” is “no change in management.” “No action” may be thought of as continuing with the present course

of action until the action is changed. CEQ states that in such instances, “to construct an alternative based on

no management at all would be a useless academic exercise.”

Mammoth to Norris

Norris to Madison

Madison to West Yellowstone

Madison to Old Faithful

Old Faithful to West Thumb

West Thumb to South Entrance

West Thumb to Fishing Bridge

Fishing Bridge to East Entrance

Fishing Bridge to Canyon

Canyon to Norris

• Warming huts are located at Mammoth, Canyon, Indian Creek, Fishing Bridge, Madison,

Old Faithful, and West Thumb. A new warming hut was approved for Norris in the 1990

Winter Use Plan for YNP. The warming huts at Canyon, Old Faithful, and Madison are

scheduled for replacement.

• YNP provides 37 miles of groomed nonmotorized trails located near Mammoth, Canyon,

Tower, Virginia Cascades, Blacktail Plateau, East Entrance, and Old Faithful.

• Nonmotorized travel is permitted throughout the park except in the Grand Canyon of the

Yellowstone and McMinn Bench.
ALTERNATIVES

41

• The winter operating season is from about mid-December to mid-March. Closures are

implemented in mid-March to protect grizzly bears as they emerge from their dens.

Actions for Grand Teton and the Parkway

• The Moose-Wilson Road is plowed from the southwest boundary to the Granite Canyon

Trailhead and from the corner near the Moose Visitor Center to the turnoff to the JY Ranch

entrance. Oversnow motorized travel is permitted between the road segments.

• Ungroomed trails open to oversnow motorized vehicle travel are the Teton Park Road from

Taggart Lake Trailhead to the summit of Signal Mountain and Jackson Lake Junction, and

the two-track that parallels the eastern park boundary.

• Groomed trails for oversnow motorized use include: the Continental Divide Snowmobile

Trail (CDST), which runs along the road shoulder from the east boundary to Flagg Ranch,

and Grassy Lake Road.

• Destination and support facilities are at Moose, Triangle X, Colter Bay, and Flagg Ranch.

• Ungroomed trails for ski and snowshoe use are available from Taggart Lake Trailhead to

Jenny Lake, along Antelope Flats Road, and near Death Canyon, Granite Canyon, Two

Ocean Lake, Colter Bay, and Flagg Ranch.

• Snowmobile and snowplane use is permitted on the frozen surface of Jackson Lake.

Alternative B

This alternative provides a moderate range of affordable and appropriate winter visitor

experiences. Key changes in recreational opportunities include: plowing the road from

West Yellowstone to Old Faithful to allow mass transit access by wheeled vehicles,

moving the CDST to a year-round path from Moran to Flagg Ranch, and phasing out

snowmobile use on Jackson Lake.

Over the next 10 years, an advisory committee would make recommendations on phasing

and implementing sound and emission standards for air quality and motor vehicle sound

issues. By winter 2008−2009, strict emission and sound requirements would be required

by all vehicles entering the parks. In addition this alternative emphasizes an adaptive

approach to park resource management, which would allow the results of new and

ongoing research and monitoring to be incorporated as it becomes available. Adaptive

management increases the Park Service’s ability to solve visitor access and experience

issues and resource issues over time. Using the criteria stated within Executive Order

(EO) 11644 (as amended) and its implementing regulation (36 CFR 2.18), monitoring

results demonstrating disturbance to wildlife or damage to park resources would be cause

to implement actions for mitigating these conditions (for example, closure to winter

visitor use or trail restrictions). Adaptive management standards, indicators, and methods

are described by management zone in Appendix I. See Figure 3. Alternative B for YNP,

and Figure 10. Alternative B for GTNP and the Parkway.

Actions Common to All Three Park Units

• This alternative would be a commitment to developing acceptable measures for mitigating

impacts, consistent with criteria in 36 CFR 2.18.

• To encourage public participation and address air quality and oversnow motorized vehicle

sound concerns, establish an advisory committee.17 The committee would include two

 

17 Established by the Secretary of the Interior under the Federal Advisory Committee Act.
CHAPTER II

ALTERNATIVES INCLUDING THE PROPOSED ACTION

42

representatives each from cooperating agencies for this EIS, environmental groups,

snowmobile industry representatives, NPS representatives, plus other state and federal

experts. The committee would recommend phasing and implementation of the standards

described below for all oversnow vehicles. Once the committee has formalized its

recommendations, it would disband. In any case, the advisory committee would not remain

in effect past the year 2010.

By winter 2008−2009, allow oversnow motor vehicles in the park only when their

emissions have been reduced by a minimum of 70% of hydrocarbons, 40% of carbon

monoxide, and 75% of particulates (with no increase in other pollutants) compared to

current 2-stroke engine emissions.18 Limit all oversnow motorized circulation in the

parks to mass transit oversnow vehicles if the technology to meet these standards is not

available for implementation in the parks by winter 2008−2009.

By winter 2008−2009, allow oversnow motor vehicles in the park only when their sound

levels are at or below 70 decibels as measured on the A-weighted scale at 50 feet at

full throttle. Limit all oversnow motorized circulation in the parks to mass transit

oversnow motor vehicles (zone 3) if the technology to meet these standards is not

available for implementation in the parks by winter 2008−2009.

Require new technologies to further reduce oversnow vehicle emissions and sound as

they are mass produced and available for public purchase.

• To improve groomed trail conditions and increase safety, prohibit late night motorized

oversnow travel (about 11 P.M. to 5 A.M.). On the CDST, travel would be prohibited from

about 8 P.M. to 5 A.M.

• To provide better access to visitor information and quality winter visitor experiences, take

the following actions:

Increase interpretive opportunities. At YNP increase interpretive opportunities related to

the unique aspects of YNP and the winter environment (geothermal, wildlife, and

scenic). Provide interpretive opportunities for motorized users at destination areas and

warming huts in both parks and on snowcoaches in the north and west sides of YNP.

Provide interpretive ski tours and programs near Tower and Canyon in YNP. At

GTNP, provide interpretive ski tours and programs through Moose, Colter Bay, and

Flagg Ranch visitor services.

Implement an aggressive information and enforcement program to ensure that oversnow

speed limits and rules are followed, and to encourage appropriate winter recreation

behavior and etiquette. Possibly implement this program in partnership with state

snowmobile associations and other snowmobile safety programs and associations.

To make visitors aware of all types of winter recreation opportunities, implement an

information program on snow and trail conditions, points of interest, and available

recreational opportunities. Implement this information program in part through

partnerships that establish NPS/visitor contact opportunities in gateway communities

and utilize state tourism program resources.

Actions for Yellowstone National Park

• To provide more opportunities for a motorized experience on narrower and less maintained

trails (zone 5), groom the following trails:

Natural Bridge

Gull Point Drive

Lake Butte Drive

 

18 Baseline emissions are defined as 1.18 grams per kilowatt-hour (g/kW-hr) brake-specific particulate matter,

202 g/kW-hr brake-specific unburned hydrocarbons, and 558 g/kW-hr brake-specific carbon monoxide.

Measure emissions using the International Snowmobile Manufacturers Association 5-mode steady-state

snowmobile engine test cycle as described in SAE-982017. Measure particulate matter emissions using a 90

mm Paliflex filtration of double-diluted exhaust gas following 40 CFR Part 86, Subpart N protocols (White

and Carroll 1998.)
ALTERNATIVES

43

• Provide additional groomed nonmotorized trail (zone 8) opportunities in the following

areas:

Indian Creek

West Entrance (The Barns)

Canyon

Riverside Drive

• Improve affordability through the addition of wheeled-vehicle access to the park’s interior.

Plow the road from West Yellowstone to Madison and Madison to Old Faithful

throughout the winter season (zone 2).

Offer a regularly scheduled shuttle bus from West Yellowstone to Old Faithful to address

air quality and sound concerns. Offer the shuttle at low cost to the public ($30 to $40).

Because parking is limited, use a reservation system to manage private vehicle and

trailer access to Old Faithful and Madison.

Maintain groomed motorized routes (zone 3) throughout the winter season from:

v The East Entrance to Fishing

Bridge

v Fishing Bridge to West

Thumb

v West Thumb to the South

Entrance

v West Thumb to Old Faithful,

Mammoth to Norris

v Norris to Canyon

v Canyon to Fishing Bridge

v Norris to Madison

Allow a planning and implementation period of 2 years. For example, plowing proposed

for the interior sections of park road would not begin until 2002−2003.

• Keep the winter season for oversnow routes as the period from mid-December to midMarch. Closures are implemented in mid-March to protect grizzly bears as they emerge

from their dens.

• Keep the plowed route from West Yellowstone to Old Faithful open from early December

to mid-March and from mid-April to mid-November.

• Continue scientific studies and monitoring regarding winter visitor use and park resources.

Close selected areas of the park, including sections of roads, to visitor use if scientific

studies indicate that human presence or activities have a detrimental effect on wildlife or

other park resources that could not otherwise be mitigated. The appropriate level of

environmental assessment under NEPA will be completed for all actions as required by

Council on Environmental Quality (CEQ) regulations (40 CFR parts 1500-1508).

Give a 1-year notice before any closure is implemented unless immediate closure is

deemed necessary to avoid impairment of park resources.

• To address wildlife issues, restrict nonmotorized uses in wildlife winter range to travel on

designated trails (zones 8 and 9).

• To provide better visitor service, increase the size and number of warming huts and other

day use facilities. Place warming huts and restrooms at popular ski trailheads (for example,

Tower), as support for motorized travel and staging areas (for example, Norris), and where

existing facility size is currently inadequate to handle the dual function of warming hut and

interpretive program staging area (for example, Canyon).

Actions for Grand Teton and the Parkway

• For access to trailheads, plow the Moose-Wilson Road from the southwest boundary to the

Granite Canyon Trailhead and from the corner near the Moose Visitor Center to the turnoff

to the JY Ranch. Plow the road from Mailbox Corner to the existing trailhead for Shadow

Mountain (zone 2).

• Provide opportunities for oversnow motorized vehicles on groomed trails (zone 5):

Continue the CDST along the road shoulder from the east boundary to Moran, but move

the trail to a new year-round path from Moran to Flagg Ranch. The path would be

located east of the highway and separated entirely from the highway footprint. The

path would be designed to take advantage of suitable resource conditions, topography,
CHAPTER II

ALTERNATIVES INCLUDING THE PROPOSED ACTION

44

and grade, so that the road could be groomed in the winter and used by bicyclists in the

summer. Opportunities for interpretation and scenic viewpoints would be

incorporated. Utilities that are currently located overhead and outside the highway

corridor would be buried near the path, which may use portions of the existing utility

corridor.

Along Grassy Lake Road.

• Provide opportunities for oversnow motorized travel on ungroomed trails (zone 7):

Between the plowed segments of the Moose-Wilson Road.

On the two-track road along the park’s east boundary from Mailbox Corner to

Cunningham Cabin, and from the plowed end of the Ditch Creek Road to the east

boundary.

• Over the first 5 years of the plans, phase out snowmobile use on Jackson Lake and permit

only snowplanes after that time (zone 7).

• Provide ungroomed nonmotorized trails from Taggart Lake Trailhead to the summit of

Signal Mountain, along Antelope Flats Road, and near Colter Bay, Death Canyon, Granite

Canyon, Two Ocean Lake, and Flagg Ranch (zone 9).

• Continue destination and support facilities at Moose, Triangle X, Colter Bay, and Flagg

Ranch and add warming hut facilities at Signal Mountain and Jenny Lake to provide for

visitor services and interpretive opportunities.

• To provide better access to visitor information and quality winter visitor experiences,

provide interpretive ski tours and programs through Moose, Colter Bay, and, Flagg Ranch

visitor services.

Alternative C

This alternative provides maximum winter visitor opportunities for a range of park

experiences, with emphasis on motorized recreation, while mitigating some natural

resource impacts and safety concerns. Key changes in recreational opportunities include:

plowing the road from West Yellowstone to Old Faithful to allow access by wheeled

vehicles, providing a widened highway corridor to accommodate the CDST, and

providing additional groomed trails for both motorized and nonmotorized uses.

This alternative directly addresses issues that arose during scoping about potential

impacts of management change on local economies. It shows how the range of winter

opportunities could be preserved, while applying minimal mitigation primarily in the

areas of air quality and sound impacts. See Figure 4. Alternative C for YNP, and Figure

11. Alternative C for GTNP and the Parkway.

Actions Common to All Three Park Units

• Beginning in winter 2002−2003 sell only 10% ethanol blend fuels for all vehicles and

synthetic low-emission motor lubrication oils for 2-stroke engines in the parks to address

air quality concerns.

• Strictly enforce current sound standards for snowmobiles (at or below 78 decibels on an Aweighted scale at 50 feet at full throttle) and in GTNP, for snowplanes (at or below 86

decibels on an A-weighted scale at 50 feet at full throttle) to address concerns about sound,

and continue to support ongoing research to develop field-reliable methods of testing

oversnow vehicle noise levels.

• Implement an information program on snow and trail conditions, points of interest, and

available winter recreation activities. This information program would be implemented in

part through partnerships that establish national park visitor contact opportunities in

gateway communities and utilize state tourism program resources.
ALTERNATIVES

45

Actions for Yellowstone National Park

• To provide more opportunities for winter use activities, increase the number of groomed

trails for both motorized and nonmotorized uses.

To provide more opportunities for a motorized experience on narrower and less

maintained trails (zone 6), groom the following additional areas for trail use:

v Utility road southeast of Norris

v Natural Bridge

v Gull Point Drive

v Lake Butte Drive

To provide more opportunities for nonmotorized trail experiences, groom portions of the

following additional areas (zone 8):

v Indian Creek

v Norris

v Fountain Flats Road

v Lower Geyser Basin (Old Faithful)

v Riverside Drive

v West Entrance (The Barns)

• Improve affordability by adding wheeled-vehicle access to the park’s interior:

Plow the road from West Yellowstone to Madison and Madison to Old Faithful

throughout the winter season (zone 2). This road would remain open to the public

throughout the fall but would close from mid-March to mid-April.

• Provide a greater range of winter recreation opportunities through the following actions:

Provide winter campsites in the park interior (for example, Old Faithful).

Maintain groomed motorized routes (zone 4) from mid-December to mid-March from the

East Entrance to Fishing Bridge, Fishing Bridge to West Thumb, West Thumb to the

South Entrance, and West Thumb to Old Faithful.

Maintain all other routes (Mammoth to Norris, Norris to Canyon, Canyon to Fishing

Bridge, and Norris to Madison) as groomed motorized routes (zone 4) from about midDecember to mid-February.

From mid-February to mid-March, open the road from Norris to Canyon and Canyon to

Fishing Bridge only for regularly scheduled mass transit snowcoaches (zone 3). This

would provide opportunities to ski or snowshoe in a quiet environment.

From mid-February to mid-March, plow the road from Mammoth to Norris and Norris to

Madison (zone 2) to allow continued late season access from the North Entrance to

Old Faithful.

Allow a planning and implementation period of 2 years; for example, the plowing

proposed for the interior sections of park road would not begin until 2002−2003.

Extend the length of the winter use season from the South Entrance to West Thumb by

two weeks from mid-March to the beginning of April.

• Provide better visitor service by increasing the size and number of warming huts and other

day-use facilities. Place warming huts and restrooms at popular ski trailheads (for

example, Tower), as support for motorized travel and staging areas (for example, Norris),

and where existing facility size is currently inadequate to handle the dual function of

warming hut and interpretive program staging area (for example, Canyon). Provide four to

five additional facilities.

Actions for Grand Teton and the Parkway

• Plow the Moose-Wilson Road and Antelope Flats Road to provide more opportunities for

visitors who wish to drive through the park (zone 2).

• Provide opportunities for oversnow motorized use on groomed trails (zone 6):

The CDST would be accommodated on a widened highway shoulder for much of the

distance from Moran to Flagg Ranch. Periodically along this length, where resource

conditions and grooming requirements can be met, the trail would depart from the
CHAPTER II

ALTERNATIVES INCLUDING THE PROPOSED ACTION

46

edge of the highway to provide a scenic diversion especially between Colter Bay and

Flagg Ranch.

Grassy Lake Road.

From the south boundary near Jackson to Moran along the eastern park boundary.

• To provide more opportunities for oversnow motorized use, develop ungroomed trails

(zone 7, except that clean and quiet technologies would not be required) from Taggart Lake

Trailhead to the summit of Signal Mountain and to Jackson Lake Junction.

• Provide opportunities for both snowmobile and snowplane use on the frozen surface of

Jackson Lake (zone 7, except clean and quiet technologies would not be required).

• Provide opportunities for nonmotorized uses on groomed trails at Gros Ventre

Campground and Two Ocean Lake (zone 8).

• Provide opportunities for nonmotorized uses on ungroomed trails from Taggart Lake

Trailhead to Signal Mountain, and near Moose, Colter Bay, Death Canyon, Granite

Canyon, and Flagg Ranch (zone 9).

• Continue the destination and support facilities at Moose, Triangle X, Flagg Ranch, and

Colter Bay. Open campground facilities and overnight accommodations at Colter Bay.

Add warming hut facilities at Jenny Lake, Signal Mountain area, and Two Ocean Lake to

enhance visitor services and interpretive opportunities.

Alternative D

This alternative emphasizes opportunities for visitor access to the unique winter aspects

of the parks (for example, geysers, geothermal areas, wildlife, and scenic vistas), and

protection of those qualities and natural resources by phasing in clean and quiet modes of

travel. It focuses winter visitor activities near destination areas and gateway

communities. Key changes in recreational opportunities include: eliminating motorized

oversnow access to Yellowstone through its East Entrance, limiting snowmobile use in

Grand Teton and the Parkway to the CDST and the Grassy Lake Road, eliminating

wheeled-vehicle access from Colter Bay to Flagg Ranch to accommodate oversnow

vehicles on the groomed highway surface, and eliminating snowmobile use on Jackson

Lake.

Emphasizing uses in different areas of the park minimizes conflicts between

nonmotorized and motorized users, and addresses issues about visitor access and

experience. Support facilities would have minimal amenities. In this alternative, visitor

access routes and timing would be modified to provide safer conditions. Over time,

issues regarding impacts on natural resources would be addressed, particularly in Grand

Teton and on the east side of Yellowstone. See Figure 5. Alternative D for YNP, and

Figure 12. Alternative D for GTNP and the Parkway.

Actions Common to All Three Park Units

• Emphasize clean quiet modes of travel to address air quality and sound concerns.

Beginning in 2002−2003, sell only 10% ethanol blend fuels for all snowmobiles and

snowcoaches and synthetic low-emission motor lubrication oils for 2-stroke engines in

the parks.

In winter 2007−2008, restrict travel to only those oversnow motor vehicles that can meet

strict emissions and sound requirements.

v Allow oversnow motor vehicles in the parks only when their emissions have been

reduced by a minimum of 70% of hydrocarbons, 40% of carbon monoxide, and

75% of particulates (with no increase in other pollutants) from current 2-stroke
ALTERNATIVES

47

engine emissions.19 Limit all oversnow vehicle circulation in the parks to mass

transit oversnow vehicles if the technology to meet these standards is not available

for implementation in the parks by winter 2008-2009.

v Allow oversnow motor vehicles in the park only when their sound levels are at or

below 60 decibels as measured on the A-weighted scale at 50 feet at full throttle.

Limit all oversnow motorized circulation in the parks to mass transit oversnow

motor vehicles (zone 3) if the technology to meet these standards is not available

for implementation by winter 2008−2009.

• Prohibit late night oversnow motorized travel (about 11 P.M. to 5 A.M.) to improve groomed

trail conditions and increase safety.

• Implement an aggressive information and enforcement program to ensure that oversnow

speed limits and rules are followed and encourage appropriate winter recreation behavior

and etiquette. Possibly implement this program in partnership with state snowmobile

associations and other snowmobile safety programs and associations.

• To increase interpretive opportunities related to the unique aspects of the parks’ winter

environment, provide interpretive programs at destination areas and warming huts in both

parks, and in snowcoaches in the north and west sides of YNP. Provide interpretive ski

tours and programs near Tower and Canyon in YNP and near Moose, Colter Bay, and

Flagg Ranch in GTNP and the Parkway.

• Implement a visitor information program on snow and trail conditions, points of interest,

and available recreational opportunities. Develop partnerships that establish national park

visitor contact opportunities in gateway communities, and utilize state tourism program

resources.

Actions for Yellowstone National Park

• Continue all currently groomed motorized routes, except for East Entrance to Fishing

Bridge. Zone designation for all remaining groomed routes would transition from zone 4

to zone 3 by winter 2007−2008.

• The East Entrance to YNP would be closed throughout the winter to address safety and

cost concerns (zone 11).

• Groom motorized routes from West Yellowstone to Madison to Old Faithful more

frequently and to a higher standard to provide smoother riding conditions.

• Where possible, use separate areas for different winter uses.

Emphasize providing nonmotorized opportunities (zones 8 and 9) in the north and

northwest areas of the park (near Mammoth, Canyon, and Tower). The following

additional areas would be groomed:

v Canyon Drives/Inspiration Point

v Washburn Overlook

Emphasize motorized oversnow route and trail opportunities (zones 3 and 5) in the west

and southwest areas of the park. The following additional areas would be groomed:

v Mesa Road

v Fountain Flats (Freight Road)

v Natural Bridge

v Riverside Drive

v Gull Point Drive

• Nonmotorized uses in wildlife winter range would be restricted to travel on designated

trails (zones 8 and 9) to address wildlife issues. Exclude backcountry areas near Mammoth

 

19 Baseline emissions are defined as 1.18 grams per kilowatt-hour (g/kW-hr) brake-specific particulate matter,

202 g/kW-hr brake-specific unburned hydrocarbons, and 558 g/kW-hr brake-specific carbon monoxide.

Measure emissions using the International Snowmobile Manufacturers Association 5-mode steady-state

snowmobile engine test cycle as described in SAE-982017. Measure particulate matter emissions using a 90

mm Paliflex filtration of double-diluted exhaust gas following 40 CFR Part 86, Subpart N protocols (White

and Carroll 1998).
CHAPTER II

ALTERNATIVES INCLUDING THE PROPOSED ACTION

48

(Bunsen Peak and Indian Creek) and Tower (Blacktail Plateau, Lost Lake, and Chittenden

Loop) from this requirement.

• Keep the length of the winter use operating season as the period from about mid-December

to mid-March.

Actions for Grand Teton and the Parkway

• Provide opportunities for oversnow motorized use on groomed routes (zone 3):

Do not plow the highway north of Colter Bay. The CDST would be accommodated as a

groomed route on the snow-covered surface of the highway from Colter Bay to Flagg

Ranch, and continue north into YNP.

• Provide opportunities for oversnow motorized use on groomed trails (zone 5):

The CDST would be accommodated on a widened highway shoulder from Moran to

Colter Bay. From Moran to the east boundary, the trail would parallel the highway as

it is now.

Grassy Lake Road.

• There would be no opportunities for oversnow motorized use on ungroomed trails, except

for snowplane use on the frozen surface of Jackson Lake (zone 7).

• Provide opportunities for nonmotorized uses on ungroomed trails from Taggart Lake

Trailhead to Signal Mountain, along Antelope Flats Road, along the east boundary twotrack from the National Forest access point to Cunningham Cabin and near Moose, Colter

Bay, Death Canyon, Granite Canyon, and Flagg Ranch (zone 9).

• Continue destination and support facilities at Moose, Triangle X, Colter Bay, and Flagg

Ranch, and add warming hut facilities at Jenny Lake.

• Winterize facilities at Colter Bay to provide a suitable staging area for snowcoaches and

snowmobiles.

Alternative E

This alternative emphasizes the protection of wildlife and other natural resources while

allowing park visitors access to a range of winter recreation experiences. It uses an

adaptive planning approach that allows the results of new and ongoing research and

monitoring to be incorporated. Key changes to current recreational opportunities are:

eliminating motorized oversnow access in Grand Teton and the Parkway except for use

on the Grassy Lake Road and north of Flagg Ranch into Yellowstone, and eliminating all

winter motorized use on Jackson Lake.

This alternative addresses the full range of winter use issues in Yellowstone over time,

but the current condition would prevail in the short term. Using the criteria stated in EO

11644 (as amended) and its implementing regulation (36 CFR 2.18), monitoring results

demonstrating disturbance to wildlife or damage to park resources would be cause to

implement actions for mitigating these conditions (for example, closure to snowmobile

use). Alternative E calls for instituting an advisory committee to make recommendations

about emission and sound standards. Local, county, state, and federal agencies as well as

representatives from the snowmobile industry and environmental groups would

participate on this committee. In Grand Teton and the Parkway, the full range of issues

are addressed more immediately by limiting oversnow motorized use to the north end of

the park, thus separating uses and eliminating most resource and visitor experience

conflicts relating to snowmobile use. Appendix I describes adaptive management
ALTERNATIVES

49

standards, indicators, and methods by management zone. See Figure 6. Alternative E for

YNP, and Figure 13. Alternatives E and F for GTNP and the Parkway.

Actions Common to All Three Park Units

• This alternative would be a commitment to the development of acceptable measures for

mitigating impacts consistent with criteria in 36 CFR 2.18.

• Encourage partnerships and public participation to address air quality and sound concerns.

Establish an advisory committee.20 The committee would include two representatives from

cooperating agencies for these Plans/EIS, two representatives from environmental groups,

NPS representatives, plus other federal, state, and snowmobile industry experts. The

committee would recommend emissions standards and sound requirements for all

oversnow vehicles for YNP and GTNP and the Parkway, as well as the phasing and

implementation of those standards to the NPS. Once the committee had formalized its

recommendations, it would disband. In any case, the advisory committee would not remain

in effect past the year 2008.

• Decrease nighttime oversnow speed limit to 35 mph to increase safety; this speed limit

would be in effect from sundown to sunrise.

Actions for Yellowstone National Park

• Continue scientific studies and monitoring related to park resources and winter visitor use.

Close selected areas of the park, including sections of roads, to visitor use if scientific

studies indicate that human presence or activities have a detrimental effect on park

resources that could not otherwise be mitigated. The appropriate level of environmental

assessment under NEPA will be completed for all actions as required by CEQ regulations

(40 CFR parts 1500-1508).

Give a 1-year notice before any closure is implemented unless immediate closure is

deemed necessary to avoid impairment of park resources.

• Restrict nonmotorized uses in wildlife winter range to travel on designated routes only (zones

8 and 9).

• Keep the length of the winter use operating season as the period from mid-December to

mid-March.

Actions for Grand Teton and the Parkway

• Provide opportunities for oversnow motorized use on groomed routes (zone 3):

Provide a groomed route on the snow-covered surface of the highway north from Flagg

Ranch.

Provide opportunities for oversnow motorized use on groomed trails (zone 5) on Grassy

Lake Road.

• Provide opportunities for nonmotorized uses on ungroomed trails from Taggart Lake

Trailhead to Signal Mountain, near Moose, at Flagg Ranch, and along the Moose-Wilson

Road (zone 9). Monitor trail use. If the use of these trails exceeds an average of 75 skiers

per day over 70% of the winter season, implement a grooming program (see Appendix I).

• Continue destination and support areas at Moose, Triangle X, Colter Bay, and Flagg Ranch

to provide for at least a minimum of visitor facilities and services.

• Provide CDST users with shuttle service from the east boundary to the route terminus at

Flagg Ranch (zone 2).

• Eliminate motorized use on Jackson Lake (Zone 9).

Alternative F

Alternative F emphasizes wildlife protection. Key changes in recreational opportunities

include: eliminating all winter access to Yellowstone’s interior through its North and

 

20 Established by the Secretary of the Interior under the Federal Advisory Committee Act.
CHAPTER II

ALTERNATIVES INCLUDING THE PROPOSED ACTION

50

West Entrances, eliminating motorized oversnow access in Grand Teton and the Parkway

except for use on the Grassy Lake Road and north of Flagg Ranch into Yellowstone, and

eliminating all winter motorized use on Jackson Lake.

For YNP this alternative addresses issues regarding protection of wildlife resources by

focusing winter visitor activities near scenic areas in the eastern and southern portions of

YNP. These areas are generally outside important winter range for large ungulate

wildlife species. In Grand Teton and the Parkway, the full range of issues is addressed

by limiting oversnow motorized use to the north end of the park, thus separating uses and

eliminating most resource and visitor experience conflicts relating to snowmobile use.

See Figure 7. Alternative F for YNP, and Figure 13. Alternatives E and F for GTNP and

the Parkway.

Actions Common to All Three Park Units

• Require technologies for reducing oversnow vehicle sound and emissions when they are

mass produced and available for public purchase. Allow a 2-year grace period for

implementation.

• To reduce the potential for vehicle-wildlife accidents, prohibit motorized travel on park

groomed routes from sunset to sunrise.

• Implement an information program on snow and trail conditions, points of interest, and

available recreational opportunities to make visitors aware of all types of winter recreation

opportunities. This information program would be implemented in part through

partnerships that establish additional park visitor contact opportunities at Jackson and

Cody.

Actions for Yellowstone National Park

• To address concerns about the use of groomed roads by wildlife, close roads from West

Yellowstone to Madison, Madison to Old Faithful, Madison to Norris, and Norris to

Mammoth to all vehicular travel from November 1 to April 30. Allow no grooming on

these routes (zone 11). If scientific monitoring indicates that the closures are not effective

in limiting unnatural wildlife migration, the NPS would consider reopening these roads.

• Keep other road segments open to oversnow motorized travel.

• Allow nonmotorized uses only on designated groomed routes (zone 8). All other areas of

the backcountry would be closed to winter visitor use (zone 11).

• To provide better visitor service, increase the size and number of warming huts and other

day use facilities where existing facility size is currently inadequate to handle the dual

function of warming hut and interpretive program staging area (for example, Canyon, West

Thumb, Norris, and Fishing Bridge).

• Shorten the length of the winter use operating season to the period from mid-December to

early March.

Actions for Grand Teton and the Parkway

Same as alternative E.

Alternative G—Preferred Alternative

This alternative emphasizes clean, quiet access to the parks using the technologies

available today. It would allow oversnow motorized access via NPS-managed

snowcoach only. Other key changes in recreational opportunities include: eliminating

winter plowing on the Colter Bay to Flagg Ranch route, making Flagg Ranch a
ALTERNATIVES

51

destination via oversnow transport, elimination of the CDST through the park, and

eliminating all winter motorized use on Jackson Lake.

This alternative addresses the full range of issues regarding safety, natural resource

impacts, and visitor experience and access. It addresses the issues in a way that would

make it necessary for local economies to adapt, and for snowmobile users to access the

parks using a different mode of transport. See Figure 8. Alternative G for YNP, and

Figure 14. Alternative G for GTNP and the Parkway.

Actions and Assumptions Common to all Three Park Units

• Permit only NPS-managed mass transit snowcoaches on designated oversnow roads.21

• Through the permitting process phase out all oversnow vehicles that do not meet the best

available environmental standards for oversnow mass transit travel. Currently, the mass

transit oversnow vehicle that produces the lowest emissions is the conversion van mat

track.22

• Allow mass transit snowcoaches only when their sound levels are at or below 75 decibels

as measured on the A-weighted scale at 50 feet at full throttle. Continue to work with

snowcoach manufacturers and operators to meet a long-term goal to lower snowcoach

sound levels to 70 decibels or lower.

• Require all new oversnow vehicles purchased by the parks to conform to the best

environmental standards available, and that other vehicles are retrofitted whenever possible

with new technologies designed to lower sound and emission levels.

• Prohibit late night oversnow travel from about 11 P.M. to 6 A.M.

• Implement an information program on snow and trail conditions, points of interest, and

available recreational opportunities. Through partnerships, establish park visitor contact

opportunities in gateway communities and utilize state tourism program resources.

• Allow a planning and implementation period of 3 (three) years.

In the winters of 2001-2003, allow existing commercial snowcoach operators to increase

their fleet size and encourage snowmobile and other new operators to purchase

coaches and reduce snowmobile numbers.

In 2002-2003 allow snowmobile use at a maximum of 50% of the current use level, at the

South and West Entrances of YNP. Current snowmobile use levels would be

maintained from the East and North Entrances of YNP.

In 2002-2003 for GTNP eliminate snowmobile use on the Teton Park Road and all

motorized use on Jackson Lake.

 In 2003-2004, all oversnow motorized visitor travel in the parks would be by snowcoach.

Close the CDST through GTNP.

• This alternative includes an affirmative commitment to implement strategies designed to

provide a reasonable level of affordable access to winter park visitors.

• Continue scientific studies and monitoring regarding winter visitor use and park resources.

Close selected areas of the park, including sections of roads, to visitor use if scientific

 

21 Note: The term “NPS managed” refers to permit management. In this case the mass transportation

snowcoach system would be provided by private concessionaires who operate under a permit from the NPS.

Under the terms of the permit or concessions contract, the NPS may stipulate, among other items, the type of

services to be offered, cost to the public, and number of visitors that may be served or transported. The NPS

may require that the types of vehicles used meet certain environmental and safety requirements. It is the

responsibility of the NPS to monitor all services offered under permit to ensure that the public and the parks

are being well served. These permits are generally offered for competitive bidding and are granted for a

specific number of years.

22 Estimates of emissions for conventional vans converted for oversnow travel indicate that the emissions

increase once the conversion is made. For this reason adherence to EPA regulations for similar wheeled vans

is neither appropriate nor required.
CHAPTER II

ALTERNATIVES INCLUDING THE PROPOSED ACTION

52

studies indicate that human presence or activities have a detrimental effect on wildlife or

other park resources that could not otherwise be mitigated. The appropriate level of

environmental assessment under NEPA will be completed for all actions as required by

CEQ regulations (40 CFR parts 1500-1508).

Give a 1-year notice before any closure is implemented unless immediate closure is

deemed necessary to avoid impairment of park resources.

Actions for Yellowstone National Park

• Continue all existing groomed motorized routes (zone 3). Evaluate snowcoach service on

the East Entrance Road if safety goals can be met. Management of avalanche danger on

the East Entrance Road may mean unscheduled closures of the road to all travel.

• Provide nonmotorized opportunities (e.g., skiing and snowshoeing) (zones 8 and 9).

Examples of existing roads or trails that would be groomed include Fountain Flats Road

and portions of the East Entrance road.

• Where feasible, set parallel tracks on one or both sides of the snow roads to facilitate

nonmotorized access.

• Increase interpretive opportunities related to the unique aspects of the winter environment

by providing interpretive programs at destination areas and warming huts. Provide guided

interpretive programs for organized groups on snowcoaches. Provide interpretive ski and

snowshoe tours and programs such as near Tower, Canyon, Mammoth, Old Faithful, West

Thumb, Madison, and West Entrance.

• Restrict nonmotorized uses in wildlife winter ranges and thermal areas to travel on

designated routes or trails (zones 8 and 9).

• Implement the winter use season during the period from late November to mid-March.

• Reduce administrative snowmobile use from the 106 currently used and supplement with

administrative snowcoaches, subject to available funding. Phase a limited number of

administrative snowmobiles to a type that meet the best available emission and sound

limits.

• Continue allowing personal non-recreation use of snowmobiles by employees and their

families living in the interior of Yellowstone; however, subject to available funding,

provide administrative snowcoaches for their use and encourage them to replace their

current snowmobiles with clean and quiet machines.

• Allow limited use of snowmobiles by concessionaires. Require clean and quiet

technologies as they are developed (through permit and contracts) and encourage the use of

snowcoaches.

Actions for Grand Teton and the Parkway

• Provide opportunities for oversnow motorized trail use (zone 3) by snowcoaches only on

the unplowed, groomed surface of the highway from Colter Bay to Flagg Ranch, and north

into Yellowstone and the Grassy Lake Road

• The park would continue to provide access to inholdings and adjacent public and private

lands using motorized means. This access would be a combination of plowed roads for

wheeled-vehicle access, and staging areas for snowmachines traveling to immediately

adjacent lands.

• Provide opportunities for nonmotorized ungroomed winter trail use (zone 9):

On the Teton Park Road from Taggert Lake Trailhead to Signal Mountain.

On Antelope Flats.

Near Colter Bay and Two Ocean Lake.

On the unplowed portion of the Moose-Wilson road.

• Continue destination and support facilities at Moose, Triangle X, Colter Bay, and Flagg

Ranch, and add warming hut facilities along the Teton Park Road to provide visitor

services and interpretive opportunities that focus on nonmotorized uses (zone 1).

• Limit backcountry nonmotorized use to designated routes to address wildlife issues in

certain wildlife winter ranges, or close certain areas to all use.
MITIGATION

53

• Winterize facilities at Colter Bay to provide a suitable staging area for snowcoach access.

• Discontinue the motorized use of Jackson Lake’s frozen surface (no snowplanes or

snowmobiles).

• Increase interpretive opportunities related to the unique aspects of the winter environment

by providing interpretive programs at destination areas and warming huts. Provide guided

interpretive programs for organized groups on snowcoaches. Provide interpretive ski and

snowshoe tours and programs at locations such as Moose, Colter Bay, and Flagg Ranch

visitor services.

• Phase in administrative snowmobile types that meet the best available emission and sound

limits. Administrative use of snowmobiles in Grand Teton is limited to law enforcement,

utility and maintenance access, and search and rescue or other use as approved by the

superintendent. Converting this use to snowcoaches would limit the ability of park

employees to respond effectively to emergencies in these areas.

MITIGATION

Alternatives analyzed in this EIS would produce environmental effects, both beneficial

and adverse. These are disclosed in Chapter IV. For adverse impacts, additional actions

are suggested for the purpose of lessening the magnitude, duration, or intensity of the

impact. These actions termed mitigation (defined in 40 CFR §1508.20) are

recommended as choices for the decision maker not already included in the alternative.23

Mitigation Common to All Alternatives

Water Resources

• Best management practices would be used during the construction, reconstruction, or

winter plowing of trails and roads to prevent unnecessary vegetation removal, erosion, and

sedimentation.

• New sanitary facilities would be constructed in locations using advanced technologies that

would protect water resources.

• Separate winter-motorized trails from drainages to mitigate the routing of snowpack

contaminants into surface water.

• Any new or reconstructed winter use sanitary facilities would be constructed in locations

and with advanced technologies that would protect water resources.

• A focused monitoring program would reduce the uncertainty of impacts from oversnow

vehicles, and if necessary indicate best management practices that might be implemented.

Wildlife, Including Federally Protected Species and Species of Special Concern

• NPS personnel would patrol sensitive resources to ensure compliance with area closures.

• Monitoring of eagle populations to identify and protect nests would continue. The park

would continue to support the objectives of the Greater Yellowstone Bald Eagle

Management Plan.

• Monitoring of wolf populations would continue.

• Lynx surveys would be undertaken to document the distribution and abundance of lynx in

the parks and their relationship to packed surfaces. The presence of other carnivores would

 

23 Many people who commented on the Draft Environmental Impact Statement (DEIS) suggested alternative

features or different mixes of alternative features. Some suggestions were appropriate as mitigation for

certain types of impacts. Most such suggestions flow logically from the determination of potential impacts

disclosed in this EIS. The EPA suggested that limitations on vehicle numbers would be necessary as an

approach to addressing air quality impacts because the benefits of alternative technologies would not

necessarily offset the impacts of increasing numbers. Some cooperating agencies suggested it would be

reasonable to limit numbers as an interim measure until a recreation carrying capacity could be set. Other

suggested measures include establishing rationing or reservation systems, permits on a first-come, firstserved basis, or other means to limit daily and annual use. If a measure or measures were selected they

would become part of the ROD (see Decision to be Made in Chapter I).
CHAPTER II

ALTERNATIVES INCLUDING THE PROPOSED ACTION

54

be documented. The parks would abide by the recommendations of the Lynx Conservation

Assessment Strategy.

• Monitoring grizzly bear populations would continue in accordance with the Interagency

Grizzly Bear Management Guidelines and the parks’ bear management plans.

• Monitoring and protecting trumpeter swan habitats and nests would continue, including the

closure of nest sites, when warranted, to public access from February 1 to September 15.

• Monitoring potential or known winter use conflicts would result in area closures if

necessary to protect wildlife habitat.

Cultural Resources

• Should the discovery of human remains, funerary objects, sacred objects, or objects of

cultural patrimony occur during construction, provisions outlined in the Native American

Graves Protection and Repatriation Act of 1990 (25 USC 3001) would be followed.

• Trails and trailheads would be sited to avoid adversely impacting known cultural resources,

including potential cultural landscapes. In addition, the use of natural materials and colors

for all permanent signs erected would allow the signs to blend into their surroundings.

Mitigation Strategies for Each Alternative

Alternative A No Action (Current Management)

Wildlife

• Continue to implement closures around wolf dens and swan and eagle nests. Closures

would be posted and enforced for the time during which the species is most sensitive to

human disturbance.

• Enhance monitoring and evaluation of backcountry nonmotorized use in GTNP, and

implement closures as necessary.

• Provide ramps or pullouts to reduce collisions between snowmobiles and moose along the

CDST.

• Continue to monitor use of groomed and plowed surfaces by bison and other ungulates.

• Conduct snow track surveys for carnivores (including lynx) on both groomed and

ungroomed routes.

Alternative B

Air Quality

Threshold: Address the EPA’s concern that unless use limits are implemented, air quality

issues could develop in areas of the three park units where they currently do not occur,

and the benefits of using less polluting fuels and lubes would be offset by increasing

numbers of oversnow vehicles.

• Set winter visitor use numbers for all three park units not to exceed the 7-year peak daily

average and the 7-year annual average until carrying capacity studies (such as mogul

development on snow roads) are complete and clean, and quiet standards implemented.

Cap use at Old Faithful at 1,000 vehicles per day. (See FEIS Appendix G for breakdown

by vehicle type.)24 The visitor scenario developed and illustrated in the visitor access

impacts section for this alternative shows use distribution in the three parks at the current

daily average snowmobile use level over the past 7 years with no net increase or decrease

in use park wide. Therefore, the scenario illustrates numbers by gateway and road segment

and can be interpreted as an interim visitor use limit. The interim cap on visitor use would

be applied by gateway. Maximum limits would include both the annual average and the

daily peak. The average for total annual and daily peak oversnow use is expressed below.

Table 6. Average total annual and daily peak oversnow use.

 

24 A 7-year interim carrying capacity was suggested in Revised Alternative E.
MITIGATION

55

Park 7-Year Average Annual

Oversnow Vehicles

7-Year Average Daily Peak

Oversnow Vehicles

Yellowstone 93,289 1,181

Grand Teton and the Parkway 25,312 300

Water and Aquatic Resources

• The new year-round CDST pathway in GTNP and the Parkway would be designed and

sited to minimize impacts to all park resources including wildlife, vegetation, and wetlands.

Any impacts to wetlands would be minimized and mitigated in accordance with NPS

Wetland Guidelines. Any needed bridges would be designed to complement, not impact,

floodplains in accordance with NPS Floodplain Management Guidelines.

• The use of bio-based fuels by the NPS and the availability of fuels in gateway communities

may result in a minor decrease in pollutant deposition into snow.

Wildlife

• Continue to implement closures around known dens and nests.

• Enhance monitoring and evaluation of backcountry nonmotorized use in GTNP, and

implement closures as warranted.

• Provide ramps or pullouts to help reduce collisions between snowmobiles and moose along

the CDST.

• Continue to monitor the use of groomed and plowed surfaces by bison and other ungulates.

• Conduct snow track surveys for carnivores (including lynx) on both groomed and

ungroomed routes.

Alternative C

Water and Aquatic Resources

• Any portion of the CDST constructed in the widened highway shoulder would be designed

to stabilize adjacent toe slopes, incorporate sufficient drainage, and protect stream banks at

crossings.

• The use of bio-based fuels by the NPS and the availability of fuels in gateway communities

may result in a minor decrease in pollutant deposition into snow.

Wildlife

• In YNP the campground use season should not be extended, and backcountry permits

should not be issued in order to mitigate any possible impacts on grizzly bears due to the

open road from the West Entrance to Old Faithful.

• The continued implementation of human use restrictions in the current Bear Management

Area will help alleviate the risks of bear/human confrontations in spring habitats.

• Where motorized use occurs near active trumpeter swan habitats in open water, sign or

plow the route to prevent vehicles from stopping.

• Backcountry monitoring and administration should be implemented in GTNP. Additional

area closures could be imposed if monitoring indicates they are warranted for the

protection of bighorn sheep and moose.

• The effects of winter use on wolves should be monitored. Areas would be closed as

necessary to protect winter and denning habitats.

• The entire length of the new, groomed motorized trail from Jackson to Moran Junction, and

the CDST from Moran Junction to Flagg Ranch should be patrolled to ensure that

snowmobilers remain on the trail and do not illegally enter areas that are important winter

range.

• The effects of the warming hut in the Two Ocean Lakes area would be monitored. If

human/bear conflicts arise, close the facility.

• Continue to monitor use of groomed and plowed surfaces by bison and other ungulates.
CHAPTER II

ALTERNATIVES INCLUDING THE PROPOSED ACTION

56

• Conduct snow track surveys for carnivores (including lynx) on both groomed and

ungroomed routes.

Alternative D

Air Quality

Threshold: Do not exceed National Ambient Air Quality Standards or Montana Ambient

Air Quality Standards in the three park units.

• Set winter visitor use numbers for all three park units not to exceed the 7-year peak daily

average and the 7-year annual average. Limit use at Old Faithful to a level not to exceed

1,000 vehicles per day. The visitor scenario developed and illustrated in the visitor access

impacts section for this alternative shows use distribution in the three parks at the current

daily average snowmobile use level over the past 7 years no net increase or decrease in

use park wide. Therefore, the scenario illustrates numbers by gateway and can be

interpreted as interim caps.

• Relocate West Entrance.25

Encourage prepaid passes until construction is complete.

Require speed limit between 10 and 20 mph.

Using modeling, determine the maximum number of snowmachines permitted to enter

each hour for all entrances (about 450 snowmachines per hour the West Entrance).26

Water and Aquatic Resources

• Any portion of the CDST constructed in the widened highway shoulder would be designed

to stabilize adjacent toe slopes, incorporate sufficient drainage, and protect stream banks at

crossings.

Wildlife

• Backcountry monitoring and administration should be implemented in GTNP. Additional

area closures could be imposed if monitoring indicates such a closure is warranted for the

protection of wintering bighorn sheep and moose.

• Providing wildlife escape routes along winter roads may mitigate some of the impacts

caused by groomed road surfaces.

• Continue to monitor use of groomed and plowed surfaces by bison and other ungulates.

• Conduct snow track surveys for carnivores (including lynx) on both groomed and

ungroomed routes.

Alternative E

Air Quality

Threshold: Achieve the lowest vehicle emissions possible (comparable to alternative G)

using current technologies. Encourage the use of new or less polluting technologies, and

allow for current peak levels of visitor access including the use of snowmobiles.

For Yellowstone National Park: A point system would be administered to cap vehicle

use when the maximum number of points is reached for each vehicle type (see Table 7).

Under this system, higher polluting vehicles would amass more points. Credits would be

earned for applying technologies that reduce emissions. This system would be

accomplished through permit administration for snowcoach vehicles and a reservation

 

25 These elements were suggested by the State of Montana.

26 Modeling is not an exact science. The hourly number of snowmobiles in Montana DEQ’s modeling

analysis was plus or minus 40% due to a lack of sufficient weather and emissions data. For the West

Entrance, a conservative estimate of 700 conventional snowmobiles per hour (minus 40%) equates to about

450 snowmobiles per hour.
MITIGATION

57

program for snowmobiles. To encourage mass transit, snowcoach vehicles would not be

limited as long as they carried at least five passengers. Since snowcoach transport is less

limiting in terms of “visitation efficiency”, there is an incentive for commercial

enterprises to convert from snowmobile operations to mass transit.

 Table 7. Point system for capping oversnow vehicle use.

Vehicle Type Vehicle

Points

Technology

Credit† Total Max DailyPoints**

Max Daily

Vehicles§

Snowmobile without bio-fuels 10 0 10

Snowmobile with bio-fuels 10 -2.5 7.5

1340 134 - 179

Snowcoach/conversion vans 1 0 N/A‡200* Up to 200

Snowcoach/Bombardiers 15 0 15

Snowcoach/Bombardiers with

pollution reduction retrofits

15 -2.5 12.5

60 4 - 5

†Variable: Increased credit would be earned proportionate to emission reductions as determined by standard testing

methods. A 25% reduction is theoretically possible by changing fuels and lubricants.

‡N/A is indicated here because the number will generally be less than 0 for vehicles of this type

**Maximum daily vehicle points are derived from Compilation of Air Pollutant Emission Factors – Volume II: Mobile

Sources, Table J-28. This source was used to identify the emission levels that were used by the State of Montana to

model oversnow vehicle emissions at the West Entrance. They reflect the amount of CO grams per mile (g/mi) emitted

by each vehicle type: roughly 1,000 g/mi (at 10 mph) for a snowmobile, 1,500 g/mi (at 10 mph) for a Bombardier and

109 g/mi (at 10 mph) for a conversion van. One point is assigned for approximately every 100 g/mi of CO emitted. Once

the maximum points are reached each day no more would be allowed to enter the parks for each vehicle type.

§Technology credits are derived by assigning 1 credit for each 10% of emission reduction achieved (i.e., up to a 25%).

Howard Haines, Montana DEQ, suggests that this level is possible. White, Carroll, and Haines, report reductions of

carbon monoxide at 38% and reductions of particulate matter at 43% (SAE 972108, 1997). Reduction in emissions may

be achieved through the use of bio-based lubricants and ethanol fuel. For vehicles utilizing those fuels, 2.5 credits would

be deducted from the overall score for that vehicle type. Credits would be given for all other technological advances that

reduce a level of pollutant in vehicle emissions as long as there is no corresponding increase in another pollutant. Credits

may be adjusted yearly. Every incremental reduction in emissions by oversnow vehicles would earn a proportionate

technology credit. A 25% reduction for bombardiers and snowmobiles is illustrated in the table to reflect a change in fuel

and lubricant use.

*200 conversion van snowcoaches would accommodate a historic peak use day in YNP.

For Grand Teton: Cap the number of visitors on Grassy Lake Road to current peak use

numbers (about 50).

Wildlife

• Backcountry monitoring and administration should be implemented in GTNP. Additional

area closures could be imposed if monitoring indicates such a closure is warranted for the

protection of bighorn sheep and moose.

• Continue to monitor use of groomed and plowed surfaces by bison and other ungulates.

• Conduct snow track surveys for carnivores (including lynx) on both groomed and

ungroomed routes.

Alternative F

Wildlife

• Recommended mitigation for this alternative includes closure of two additional areas in

GTNP to backcountry use: Blacktail Butte and Wolff Ridge. Close the south- and westfacing slopes of Blacktail Butte from the valley floor to the summit, and close all aspects of

Wolff Ridge. Additional closures could be imposed if monitoring indicates such a closure

is warranted for the protection of wintering species.

• Backcountry monitoring and administration should be implemented in GTNP.
CHAPTER II

ALTERNATIVES INCLUDING THE PROPOSED ACTION

58

• In GTNP close important bighorn sheep winter range in the north and south Teton Range27

• Provide wildlife escape routes along motorized winter roads and trails.

• Continue to monitor use of groomed, ungroomed, and plowed surfaces by bison and other

ungulates.

• Conduct snow track surveys for carnivores (including lynx) on both groomed and

ungroomed routes.

• Cap use at the average daily use for each road segment in each park. See visitor scenario

for this alternative showing average daily use by segment under Effects on Visitor Access,

alternative F, Chapter IV, and in Appendix G.

• Snowmobiles must be accompanied by a NPS-permitted guide and travel in groups of 6 to

11 (includes guide), except for Grassy Lake Road.

• To avoid the crepuscular hours when wildlife is most active, snowmobiles would be

permitted to travel in the parks only between the hours of 9 A.M. and 3:30 P.M.

• Before entering the park all oversnow vehicle operators would be required to review a

video highlighting appropriate procedures and behaviors to reduce wildlife impacts.

Alternative G—Preferred Alternative

Interim Snowmobile Use Limits

• During the winters of 2000-2001 and 2001-2002, hold visitation by snowmobiles as

follows:

Set snowmobile use numbers for all three park units at levels not to exceed the 7-year

peak daily average. The visitor scenario developed for alternative A (Appendix G)

shows snowmobile use distribution at YNP gateways, and by road segments in the

three parks at both the current daily average and peak average snowmobile use levels

over the past seven years. The scenario provides numbers that can be expressed as

interim visitor use limits. Maximum daily limits at the entrances would be set at the

average peak day snowmobile use (see Table 8).

Cap use at Old Faithful at 1000 vehicles per day.

The maximum number of snowmobiles to be passed through the West Entrance would be

limited to 400 snowmobiles per hour. For snowplane use on Jackson Lake reissue

permits to permit holders of record and do not issue any new permits. Limit

snowmobile use on Jackson Lake to 30 per day.

 

27 Southern Tetons: 1) in the Prospectors Mountain and Mount Hunt areas (including peak 10,988), all areas

above 3,000 meters (m) (9,900 feet (ft.)), and south-facing slopes on Mount Hunt above 2,600 m (8,580 ft.);

2) the slopes of Static Peak above 3,300 m (10,890 ft.) (does not affect Albright Peak); and 3) the southfacing slopes above 3,000 m (9, 900 ft.) along the north side of Avalanche Canyon and the north fork of

Avalanche Canyon.

Northern Tetons: 1) in the Ranger-Doane-Eagles Rest area (including peaks 10,298, 10,881, 10,023, 10,686),

all areas above 3,000 m (9,900 ft.), and south-facing slopes of Eagles Rest above 2,600 m (8,580 ft.); 2) in

the Elk Mountain-Owl Peak area, all areas above 3,000 m (9,900 ft.), and south-facing slopes above 2,600 m

(8,580 ft.); 3) on Forellen Peak, all areas above 2,800 m (9,240 ft.) and south-facing slopes above 2,500 m

(8,250 ft.); and 4) the ridge crest and south-facing slopes of the cliffs at the mouth of Moose Creek (also

known as the Lower Berry Cliffs) above 2,300 m (7,590 ft.).
MITIGATION

59

Table 8. Interim cap on snowmobile use in alternative G for Yellowstone/Grand

Teton/Parkway area road segments.

Road Segments Average Peak Day*

Snowmobile Use

Average Daily

Snowmobile Use

Mammoth to Northeast Entrance 0 0

Mammoth to Norris 40 30.5

West Entrance to Madison 975 554.2

Madison to Norris 435 247.0

Norris to Canyon Village 325 184.5

Canyon Village to Fishing Bridge 260 148.1

Fishing Bridge to East Entrance 65 36.4

Fishing Bridge to West Thumb 220 125.1

Madison to Old Faithful 860 488.6

Old Faithful to West Thumb 370 209.4

West Thumb to Flagg Ranch 275 175.8

Grassy Lake Road 40 24.2

Flagg Ranch to Colter Bay 40 24.3

Colter Bay to Moran Junction 40 24.3

Moran Junction to East Entrance 40 24.3

Moran Junction to South Entrance 0 0

Teton Park Road 20 10.4

Moose-Wilson Road 5 3.0

Antelope Flats Snowmobile Route 0 0

*Average daily use numbers are provided for information. The average daily peak use shown in this column, rounded

to the nearest five snowmobiles, is considered the maximum

Wildlife

• Continue to assess grizzly bear abundance, distribution, and habitat selection, including the

location of dens. The information obtained will assist park managers in protecting

important habitats and planning recreational activities that minimize disturbance to bears.

• Conduct snow track surveys for carnivores (including lynx) on both groomed and

ungroomed routes.

• Continue to monitor use of groomed, ungroomed, and plowed surfaces by bison and other

ungulates.

Research Needs

All alternatives call for determining visitor use carrying capacities. Visitor carrying

capacities would be based on studies that set indicators and standards for desired visitor

experiences and resource conditions. These carrying capacities would require that

indicators be monitored to ensure that desired experiences and conditions are maintained.

Resource inventory, monitoring, and adaptive management are proposed and require the

establishment of baselines and thresholds upon which to assess the degradation to park

resources. Although EOs 11644 and 11989 and their implementing regulation 36 CFR

§2.18 direct the NPS to manage certain resources for their protection, they provide little
CHAPTER II

ALTERNATIVES INCLUDING THE PROPOSED ACTION

60

guidance as to acceptable thresholds. The research needs identified below will help to

determine appropriate thresholds, evaluate management outcomes relative to these

thresholds, and assist in the development of management alternatives and mitigation.

Research findings will provide systematic feedback for winter use management and input

for mitigation of unplanned or undesirable effects on park resources and visitor

experiences.

• Research grizzly bear movements to provide information on bear expansion throughout the

GYA. Specific information on grizzly bear movements, habitat use, and den locations will

allow an evaluation of potential areas of grizzly/visitor conflict, and assist park managers in

protecting important habitats and in planning recreational activities that minimize

disturbance to bears. Specifically, the effects of snowmobiling on denned grizzly bears

need to be discerned, and areas of potential conflict delineated.

• Conduct lynx surveys to evaluate population levels and distribution, especially in relation

to winter recreation areas and other potential competitors. Because snow compacting

activities (e.g., grooming, the use of oversnow motorized vehicles, and skiing) may allow

other carnivores to compete with lynx in areas where they would otherwise be restricted by

deep snow, it is important to determine whether these activities affect lynx in the parks. In

addition to lynx surveys, recording the presence and abundance of snowshoe hares, the

primary prey of lynx, can provide information on potential lynx habitats, and overtime

serve as an index to predict lynx population densities and trends.

• Systematically survey and monitor ungulate winter ranges. Ungulates are highly stressed

in the winter and their energy reserves are taxed. Winter visitors can further deplete

ungulates’ reserves by causing them to flee or by displacing them to lower quality habitats.

The parks have implemented closures in some important ungulate wintering areas. Some

of the alternatives call for additional restrictions and closures. To ensure the efficacy of

regulating visitor use, it is necessary to survey and monitor ungulate ranges and assess

potential and ongoing conflicts with winter recreation.

• Research and evaluate the impacts of winter recreation on wolverines. Wolverines occur in

low-density populations and are one of the least studied carnivores in North America.

They are believed to be extremely sensitive to human disturbance, especially during the

denning period (Copeland 1996). This sensitivity combined with increasing winter

recreation use warrants more specific information on wolverines and the effects of winter

recreation. The results of such a study could be used to develop guidelines to minimize

potential conflicts between winter visitors and wolverines.

• Measure water chemistry associated with streams and other water bodies at high risk to

snowmelt pollutant runoff. Evaluate the impacts of changes in water chemistry or

pollutants on riparian biological systems at high risk from snowmelt pollution. Investigate

potential downstream accumulations of products from internal combustion engines and

associated fuels or lubricants.

• Continue the study of the formation and geometry of moguls (Alger et al. 2000).

Investigate the formation of moguls to determine the best means to groom trails to

minimize roughness. Investigate in connection with weather parameters such as snow

temperature, free water content, and new snow.

• Investigate the visitor’s ability to experience park values such as opportunities to view

wildlife and scenery, clean air, natural quiet, and solitude. Investigate the intrinsic value of

these resources as well as their value to park visitors, non-park visitors, and those persons

who hope to visit the parks someday.

ALTERNATIVES CONSIDERED BUT ELIMINATED FROM DETAILED

STUDY

In response to scoping, several comments included suggestions for alternatives or

alternative actions. Many of these suggestions may be found in the alternatives
ALTERNATIVES CONSIDERED BUT ELIMINATED FROM DETAILED STUDY

61

considered in detail; others were eliminated from study. During the alternative

formulation process, cooperating agencies and agency personnel participated in

workshops to develop ideas for alternatives. Many of the ideas were incorporated into

the alternatives analyzed in detail. Appendix A provides a detailed description of this

process and the ideas generated, including the rationale for eliminating ideas. The

alternative ideas and rationale for their elimination are presented below.

• Alternate years for skiing and snowmobiling. Effective management of concessions,

businesses, and park facilities depends on a degree of consistency in use and types of use

from year to year. This alternative does not appear to be logistically feasible for managers

or supportive of the needs and plans of the business community.

• Establish a monorail. Although the benefits of this alternative might eventually prove to

be substantial, implementation costs would be enormous. Because a hyper-car system

would be a year-round improvement and not strictly a winter use item, this action would be

best addressed in a general management plan. Establishing a monorail is economically

unfeasible at present.

• Open additional areas of the parks to disperse and accommodate use. Most areas of the

parks outside road corridors are in recommended or potential wilderness. They are,

therefore, unavailable for allocation to the suggested motorized uses. For example, use of

mechanical equipment to groom ski trails in recommended wilderness is inappropriate.

• Open more gateways to the parks. See previous suggestion. Current locations for access

to the parks are the only possible locations considering areas of recommended wilderness.

In addition, a large part of the perimeter around both parks abuts congressionally

designated wilderness on national forests.

• Increase/decrease access to areas of the parks by opening/closing trails. See previous

two suggestions.

• Eliminate oversnow motorized use in the parks. Oversnow motorized use is considered

within the range of recreational opportunities to be provided. This alternative is essentially

the same as The Natural Regulation Alternative recommended by The Fund for Animals.

Total elimination of oversnow motorized use without analysis would not be within the

scope of the purpose and need for action. Alternative G approaches this issue by

eliminating snowmobiles in favor of access by snowcoach mass transit. However,

snowmobile use is allowed (on designated routes only) under NPS regulations (36 CFR

2.18). A determination must be made that snowmobile use is consistent with the parks’

natural, cultural, scenic, and aesthetic values, safety considerations and management

objectives, and will not disturb wildlife or damage park resources. Within the range of

alternatives in this FEIS there are a variety of features that close various portions of the

parks to various types of winter uses. Comparisons of effects can be made between

alternatives in which road segments or areas are closed, opened, or managed differently.

The comparison can facilitate the determination of impacts on park resources or wildlife

where sufficient data is available, resulting in closure as part of the selected alternative.

Two alternatives, B and E, are constructed around adaptive management themes. These

alternatives dictate implementation of focused monitoring programs to determine explicitly

whether such impacts occur. Further, upon such determination through monitoring results,

closures are prescribed in accordance with the regulation cited above.

• Plow the road from West Yellowstone to Old Faithful and establish a snowmachine route

along the road. Due to the high volume of winter visitor use, establishing a bimodal

transportation route on the roadways from West Yellowstone to Madison to Old Faithful

would pose significant safety risks to park visitors and employees. This action would

create the same safety concerns that have been identified on the CDST.

• Open existing facilities in the park interior to dispersed use – for example Canyon, Grant

Village, or Lake. A reference to other plans and environmental analysis in Chapter 1
CHAPTER II

ALTERNATIVES INCLUDING THE PROPOSED ACTION

62

includes commercial services plans for both parks. Since these plans are already in

process, the decision was made not to include any detailed analysis of commercial facilities

in the Winter Use Plans/EIS.

ALTERNATIVES SUGGESTED DURING THE PUBLIC COMMENT PERIOD

Approximately 46,500 comment letters were received during the public comment period

for the DEIS. Of that number 93%, or about 43,100 documents, expressed support for

one of five alternatives:

• The Natural Regulation Alternative submitted by The Fund for Animals et al.

• The Citizens’ Solution submitted by the Greater Yellowstone Coalition et al.

• The Jackson Hole Alliance Proposal

• The State of Montana’s alternative

• Revised Alternative E, submitted by the cooperating counties, the State of Wyoming and

the Blue Ribbon Coalition.

Of the letters that indicated support for an alternative, 44% supported Revised

Alternative E; 45% supported The Citizens’ Solution, and 4% supported The Natural

Regulation Alternative. As a whole, The Natural Regulation Alternative was determined

to be outside the scope of analysis including its provision for a monorail system in YNP

(see Alternatives Considered but Dismissed from Detailed Study–Eliminate Oversnow

Motorized Use in the Parks above).

The alternative features suggested in Revised Alternative E and The Citizens’ Solution

are a compilation of various alternative features already included in the range of

alternatives considered (see Chapter I, Decision to be Made). Other features in these

suggested alternatives are mitigation and implementation strategies. Where appropriate,

these strategies have been incorporated into the range of alternatives evaluated in this

FEIS, and are available for selection by the decision maker in the Record of Decision.

Public comment letters on the DEIS have either been reproduced in their entirety or

summarized and may be located along with the responses to them in Volume III, Public

Involvement. For convenience, summaries of Revised Alternative E and The Citizens’

Solution are provided in Table 9 and Table 10, showing where a particular action has

been described and analyzed in the range of alternatives.

Table 9. Summary of The Citizens’ Solution.

General Features of Winter Use Plans Alternatives

The Citizens’ Solution A B C D E F G Notes

Phase out all snowmobile use in the 3 parks

over the next 3 years

X* *Alternative G specifies a 2-year

implementation schedule

Eliminate the CDST in GTNP X X X
ALTERNATIVES SUGGESTED DURING THE PUBLIC COMMENT PERIOD

63

Provide only mass transit snowcoach access

on current oversnow roads in Yellowstone

X

Close Yellowstone's East Entrance X X* *No snowcoaches through East

Entrance currently

Expand research on winter related impacts

to park values

X X X

Establish winter visitor carrying capacity X X X X X X X

X = Suggested feature is included in the range of alternatives presented in the DEIS and FEIS.

M = Suggested feature is included as mitigation in the range of alternatives presented in the FEIS.

Table 10. Summary of Revised Alternative E.

General Features of Winter Use Plans Alternatives

Revised Alternative E A B C D E F G Notes

Utilize only EPA standards to regulate emissions X X

Commitment to the development of acceptable measures

consistent with criteria in 36 CFR 2.18

X X

Establish FACA† Committee to advise on management

of wildlife, air quality, and other resources* as well as

implementation of mobile emission AND sound

standards

X* X* *Advisory committee

for emissions/sound

standards only

Require the sale of bio-based fuels; require all

commercial operators to use these fuels. Promote prepaid passes at all entrances*

X* X X X

M*

X *Passes are currently

available in West

Yellowstone

Move West Entrance, implement 10 to 20 MPH speed

limit; model hourly maximum emissions at all entrances

M* *Suggested by State of

Montana

Relocate CDST to year round path X

Improve grooming on Grassy Lake Road Grooming standard is

not a significant issue

Keep snowplane & snowmobile use on Jackson Lake X X

Eliminate snowmobiles on interior Teton Park Road X X X X X

Eliminate snowmobiles on Moose-Wilson Road X X X X X

Continue existing winter facilities; add warming huts X X X X X

Nighttime closure from 10 P.M. to 6 A.M. X X X

Aggressive information program using video technology X X X X

Open existing facilities to winter use (e.g. Colter,

Canyon*)

X X X *Defer to NPS

Commercial Services

Plan

In YNP, restrict nonmotorized uses in wildlife winter

range to travel on designated trails only

X X X X* X *Total area closure in

YNP

In GTNP, restrict nonmotorized uses in key wildlife

winter range

X X X X X X

M*

X* *Adds bighorn sheep

closures

Establish interim winter visitor carrying capacity based

on 7 year average *of winter visitor use

M M *Carrying capacity

study in all alternatives

Continue scientific studies and monitoring related to

park resources with independent 3rd party review by

National Academy of Sciences (NAS)*

X X *Review by NAS not

stipulated in any

alternative

X = Suggested feature is included in the range of alternatives presented in the DEIS and FEIS.

M = Suggested feature is included as mitigation in the range of alternatives presented in the FEIS.

†

FACA = Federal Advisory Committee Act
CHAPTER II

ALTERNATIVES INCLUDING THE PROPOSED ACTION

64

SUMMARY OF ALTERNATIVES AND EFFECTS

As required in the CEQ regulations, this chapter presents the alternatives and their

environmental impacts in a comparative form. The following two tables list the issues

and provide a clear basis of choice for the decision maker. Table 11 is a summary of

alternative features and Table 12 is a summary of effects for all alternatives.
Table 11. Summary of Alternatives

ALTERNATIVE A

NO ACTION

ALTERNATIVE B

PREFERRED ALTERNATIVE

ALTERNATIVE C ALTERNATIVE D ALTERNATIVE E ALTERNATIVE F ALTERNATIVE G

Visitor Use & Access

Yellowstone

• Maintain current 180 miles of groomed

oversnow motorized road

• Maintain current 37 miles of groomed

nonmotorized

• Maintain 76 miles of plowed road (include Hwy

191 to Cooke City)

• Existing winter season from mid December to

mid March

GT/JDRMP

• 100 miles plowed road

• 33.9 miles groomed motorized trail

• 35.6 ungroomed motorized trail or area

• 26.4 ungroomed non- motorized trail or area

All Units

• Increase interpretive opportunities

Yellowstone

• Establish 6 miles of new oversnow motorized trails

• Establish 10 miles of new nonmotorized trails

• Allow all-wheeled public shuttle vehicle access by plowing the road

from West Yellowstone, MT to Old Faithful

• Lengthen season by two weeks from the West Entrance

• Increase size and number of warming huts and other day-use

facilities

• Continue scientific studies in re: impacts of winter visitor use and

park resources; close selected areas or road segments if no other

possible mitigation method

GT/JDRMP

• Establish 6.5 miles of new nonmotorized trail

• Continue current & add destination facilities

• Provide interpretive ski tours

• 5-year phase-out of snowmobiles on Jackson Lake

Yellowstone

• Establish winter campsites (e.g. Old Faithful

area)

• Establish 10 miles of new oversnow motorized

trails

• Establish 20 miles of new nonmotorized trails

• Allow all-wheeled private and public shuttle

vehicle access from West Yellowstone, MT to

Old Faithful

• Lengthen season by two weeks in December

from West Yellowstone to Old Faithful and two

weeks in March from the South Entrance to

West Thumb

• Plow the road from Mammoth to Norris to

Madison mid-Feb to mid-Mar to allow lateseason access

• Snowcoach only from Norris to Canyon to

Fishing Bridge mid February to mid March

• Increase size and number of warming huts and

other day-use facilities

GT/JDRMP

• Establish 30.4 miles of new oversnow

motorized trail

• Establish 6 miles of new nonmotorized trail

• Allow all-wheeled access by plowing the

Moose-Wilson and Antelope Flats Roads

• Allow both snowmobiles and snowplanes on

Jackson Lake

• Continue current & add destination facilities

All Units

• Increase interpretive opportunities

Yellowstone

• Separate use by establishing 15 miles of new

oversnow motorized trails in the W and SW areas,

and 6 miles of new nonmotorized trails in the N

and NW areas

GT/JDRMP

• Establish 18 miles of new oversnow motorized

route by opening road north of Colter Bay to

snowmobiles

• Continue current & add destination facilities

• Increased and enhanced visitor programs facilities

and interpretive opportunities

All Units

• Continue scientific studies in re: impacts

of winter visitor use and park resources;

close selected areas or road segments if no

other possible mitigation method

Yellowstone

• Restrict backcountry skiing to use of

designated trails or routes only in

important winter range

GT/JDRMP

• Establish 8.6 miles of new nonmotorized

trail

• CDST eliminated through GTNP

• Oversnow motorized uses are eliminated

except for Grassy Lake Trail and groomed

motorized route north of Flagg Ranch

Yellowstone

• Close sections of road from the

West Entrance to Madison

Junction and Madison Junction

South to Old Faithful and the road

segments from Mammoth south to

Norris Junction and from Norris

Junction south to Madison

Junction

• Restrict skiing to use on frontcountry designated trails.

Backcountry use would be

prohibited

• Winter use season from midDecember to early March

GT/JDRMP

• Same as Alternative E

All Units

• Increase interpretive opportunities

• Snowcoach only travel

Yellowstone

• Groom 11 miles of nonmotorized

trail

GT/JDRMP

• Continue current & add destination

facilities

• Establish 4 miles of new

nonmotorized trail

• Open the road from Colter Bay to

the South Entrance to snowcoaches

• Open the Grassy Lake Road from

Flagg Ranch to the west boundary

for snowcoach travel

Human Health & Safety

All Units

• Over-snow speed limit 45 mph except for the

Moran to Flagg Ranch segment, which is 35

mph.

All Units

• Prohibit late-night oversnow travel 11 P.M. to 5 A.M.

• Implement information and enforcement program

GT/JDRMP

• Separate auto use from snowmachine use by moving CDST to new

pathway between Moran and Flagg Ranch

• Separate motor and nonmotor uses on interior park road; allow

nonmotorized use only from Taggert Lake Trailhead to Signal

Mountain

• Prohibit snowmachine use on CDST 8 P.M. to 5 A.M. to allow for

groomers

GT/JDRMP

• Move the CDST to a widened highway

shoulder between Colter Bay and Flagg Ranch

All Units

• Prohibit late-night oversnow travel

• Implement information and enforcement program

Yellowstone

• Close East Entrance road

• Groom from West Yellowstone to Madison to Old

Faithful more frequently

GT/JDRMP

• Move the CDST to unplowed road from Colter

Bay to Flagg, and to widened highway shoulder

from Colter to Moran

• Nonmotor use only on interior park road

All Units

• Reduce nighttime oversnow speed limit to

35mph

GT/JDRMP

• Separate motorized and nonmotorized

opportunities

All Units

• Prohibit night oversnow travel,

sunset to sunrise

GT/JDRMP

• Same as Alternative E

All Units

• Prohibit late-night oversnow travel

Local Communities & Adjacent Lands

All Units

• The 1999 Interagency Winter Visitor Use

Assessment shows relationships and cooperative

programs for winter use in the GYA

• NPS visitor contacts are provided at visitor

centers in West Yellowstone and Jackson Hole.

All Units

• Implement information program in cooperation with local

communities

• Establish advisory committee to phase and implement emission

standards

All Units

• Implement information program in cooperation

with local communities

All Units

• Implement information program in cooperation

with local communities

All Units

• Establish advisory committee

All Units

• Implement information program in

cooperation with local

communities

All Units

• Implement information program in

cooperation with local communities

Natural Resources

All Units

• Enforce current sound standards, 78dB(A)

• Bio-lubes and fuels used by NPS

All Units

• Establish advisory committee

• Require new technologies

• Phase in more stringent standards for oversnow vehicle emissions

• All oversnow vehicle sound emissions must be at or less than 70

dB(A)

• Monitor natural resources at current levels of administration, and use

regulatory measures when necessary to prevent identified

disturbances resulting from winter recreation use

Yellowstone

• Continue scientific studies in re: impacts of winter visitor use and

park resources; close selected areas if no other possible mitigation

method

• Restrict nonmotorized use to designated important winter range

GT/JDRMP

• Phase in motorized use by snowplanes only on Jackson Lake

All Units

• Enforce current sound standards, 78dB(A)

• Manage wildlife same as in Alternative A

• Phase in alternative fuel/lube sales to public

Yellowstone

• Provide quiet nonmotorized environment by

restricting Norris to Canyon to Fishing Bridge

road to snowcoaches mid-Feb to mid-Mar

All Units

• Oversnow vehicle sound emissions must be at or

less than 60 dB(A)

• Phase in alternative fuel/lube sales

• Phase in more stringent standards for oversnow

vehicle emissions

Yellowstone

• Restrict nonmotorized use to designated trails in

important winter range, except in the Tower and

Mammoth areas

GT/JDRMP

• Allow motorized use by snowplanes only on

Jackson Lake (no snowmobiles on Jackson Lake)

All Units

• Establish advisory committee to

recommend emission standards for

oversnow vehicles

• Monitor natural resources at current levels

of administration, and use regulatory

measures when necessary to prevent

identified disturbances resulting from

winter recreation use

Yellowstone

• Restrict nonmotorized use in important

winter range

GT/JDRMP

• CDST would be accessed via shuttle from

east boundary to Flagg Ranch

• Eliminate motorized use on Jackson Lake

All Units

• Require new technologies for

reducing snowmobile emissions as

they are developed by industry

Yellowstone

• Close road from West

Yellowstone to Madison to Old

Faithful from Nov 1 to Apr 30

• Allow nonmotorized uses only on

groomed trails in frontcountry

• Shorten the season by two weeks

in March

GT/JDRMP

• Same as Alternative E

All Units

• Sound emissions must be at or less

than 75dB(A) trending to 70dB(A)

• Restrict oversnow motorized travel

to snowcoaches which meet the

best environmental standards

available

• Continue scientific studies in re:

impacts of winter visitor use and

park resources; close selected areas

if no other possible mitigation

method

• Restrict nonmotorized use to

designated important winter range

GT/JDRMP

• Discontinue all motorized use on

Jackson Lake

• Close important bighorn sheep

winter habitat to backcountry use
CHAPTER II

ALTERNATIVES INCLUDING THE PROPOSED ACTION

66
Table 12. Summary of Effects*

*Summary Statements Above Are Abbreviated And Taken Out Of Context To Provide A Quick Comparison By Element.

The Reader Is Encouraged To Review The Supporting Analysis In Chapter IV.

ALTERNATIVE A

No Action ALTERNATIVE B ALTERNATIVE C ALTERNATIVE D ALTERNATIVE E ALTERNATIVE F

ALTERNATIVE G

Preferred Alternative

Socioeconomic

• Social: continued values and beliefs conflicts

• No policy related impacts on economics

would result under alternative A.

• Continued high cost of winter visitor access.

• Negligible to minor effects on local & state

economies.

• Major negative effect gateway communities

(West Yellowstone).

• Moderate negative effects on total

nonmarket visitor benefits (through reduced

visitation).

• Minor to moderate benefit to low-income

visitors.

• Negligible to minor effects on local & state

economies.

• Major negative effect on gateway

communities (West Yellowstone).

• Moderate negative effect on total nonmarket

visitor benefits (through reduced visitation).

• Minor to moderate benefit to low-income

visitors.

• Negligible to minor effect on local and state

economies.

• Minor negative effect on total nonmarket

visitor benefits (through reduced visitation).

• No short-term effects compared to current

condition.

• Negligible to minor effect on local and state

economies.

• Larger, major adverse effect on the

economies of gateway communities (W.

Yellowstone and Gardiner).

• Minor negative effect on total nonmarket

visitor benefits (through reduced visitation).

• Minor effect on local and state

•

• mies.

Minor negative effect on total non

visitor benefits (through reduced

visitation).No

t

-term effects p

a• red to current condition.Negligible to minor

effect on local and state economies.

Larger, major adverse effect

• on the economies of gateway communities

(W. Yellowstone and Gardiner).

Minor negative effect on total nonmarket

• visitor benefits (through reduced

visitation).Minor effect on local and state

economiesor cultural landscapes.

• With appropriate mitigation, no adverse

effects on archeological or historic

resources, or cultural landscapes.

• With appropriate mitigation, no adverse

effects on archeological or historic

resources, or cultural landscapes.

• With appropriate mitigation, no adverse

effects on archeological or historic

resources, or cultural landscapes.

• With appropriate mitigation, no adverse

effects on archeological or historic

resources, or cultural landscapes.

• With appropriate mitigation, no adverse

effects on archeological or historic resources,

or cultural landscapes.

Air Quality and Public Health

• Continued minor and adverse effects from

emissions exposure parkwide.

• Continued moderate and adverse local

effects at major staging areas.

• Continued adverse impacts on employees

who work at entrances, destination and

staging areas.

• Vehicular emissions would continue to cause

localized and perceptible visibility

impairment near vicinity of the West

Entrance, Old Faithful and Flagg Ranch.

• Emissions along heavily used roadways

would result in localized visibility

impairment.

• Major beneficial effects would occur at the

W. Entrance, Old Faithful and Flagg Ranch

due to reduced PM10 and CO.

• Moderate to minor beneficial effects dye to

reduced CO and PM10 concentrations at other

locations where snowmobiling is permitted,

once strict emission requirements are

implemented.

• Minor beneficial effects due to reduced CO

concentrations along the Flagg Ranch to

Colter Bay roadway and the Teton Park Rd.

• Relative to existing condition, improved

visibility at West Entrance and Old Faithful.

• Vehicular emissions would not cause any

perceptible visibility impairment in the

vicinity of W. Entrance or along park

roadways.

• Major beneficial effects at the W. Entrance

and along the roadway to Madison and Old

Faithful.

• Moderate reductions in CO at the Old

Faithful staging area.

• Minor reductions in CO at Flagg Ranch and

along the road to Colter Bay.

• Minor to moderate adverse effects

(compared to alternative A) where oversnow

vehicles would be permitted.

• Relative to existing condition, improved

visibility at West Entrance.

• Vehicular emissions would not cause any

perceptible visibility impairment in the

vicinity of W. Entrance or along the

roadways.

• Perceptible visibility degradation could

occur in the vicinity of Old Faithful and

Flagg Ranch during periods of high use.

• Moderate and major beneficial effects at the

West Entrance and along the road to Old

Faithful.

• Increased traffic at Flagg Ranch and on the

road to Colter Bay would result in major

adverse impacts to air quality if mitigating

use limits were not implemented.

• Moderate beneficial effects would occur

where snowmobiling is permitted, once strict

emission requirements were implemented.

• Relative to existing condition, improved

visibility at W. Entrance and Old Faithful.

• Vehicular emissions would cause localized,

perceptible, visibility impairment near the

vicinity of W. Entrance and in the area

around Old Faithful and Flagg Ranch.

• Vehicular emissions along roadways would

not result in perceptible visibility

impairment.

• In the short term, effects would be the same

as described in No Action.

• In the long term, negligible to moderate

beneficial improvements in air quality near

the W. Entrance and other staging areas in

YNP-- depending on emissions standards

required by FACA committee.

• Moderate and major beneficial impacts

would occur in GTNP due to the prohibition

of snowmobiles on the roadway from Colter

Bay to Flagg Ranch and Teton Park Road.

• Vehicular emissions would continue to cause

localized and perceptible visibility

impairment near vicinity of the W. Entrance,

Old Faithful and Flagg Ranch.

• Emissions along heavily used roadways

would result in localized visibility

impairment.

• Moderate improvements to visibility in W.

Entrance vicinity.

• Negligible beneficial effects at Old Faithful.

• Negligible to minor adverse effects would

occur at Flagg Ranch.

• Moderate and major beneficial effects to air

quality would occur on the road from Flagg

Ranch to Colter Bay and Teton Park Road.

• Vehicular emissions would not cause any

perceptible visibility impairment in the

vicinity of W. Entrance or along the

roadways.

• Perceptible visibility degradation could

occur in the vicinity of Old Faithful and

Flagg Ranch during periods of high use.

• Major beneficial effects in air quality at the

W. Entrance and along the road to Old

Faithful.

• Minor beneficial effects at Old Faithful and

Flagg Ranch due to reduction in CO and

major beneficial effects from the reduction of

PM10.

• Major beneficial reductions in CO and PM10

are predicted along the roadway from Flagg

Ranch to Colter Bay.

• Vehicular emissions would not cause any

perceptible visibility impairment in the

vicinity of W. Entrance along park roadways

or in the vicinity of Old Faithful and Flagg

Ranch.

Public Safety

• Continued minor adverse effects to visitor

and employee safety along the road from W.

Entrance to Old Faithful and the CDST.

• Continued minor to moderate adverse effects

on winter visitors and employees who use

the E. Entrance.

• Moderate beneficial improvements due to

mass transit in YNP and separation of uses

in GTNP, including new CDST pathway.

• Minor beneficial improvements in the parks

due to the introduction of several positive

safety-oriented measures in the absence of

any additional safety risks.

• Moderate adverse effects in YNP due to the

potential for increasing visitor conflicts and

vehicle/animal collisions.

• Minor improvement due to widened

highway shoulder for the CDST.

• Minor beneficial improvements in the parks

due to the introduction of several positive

safety-oriented measures in the absence of

any additional safety risks.

• Minor improvement due to widened

highway shoulder for the CDST and

removal of wheeled vehicle traffic from

Colter Bay to Flagg Ranch.

• Negligible improvements, as compared to

alternative A, in all three-park units due to

oversnow nighttime speed limits.

• Moderate beneficial improvements in GTNP

due to decrease in oversnow motorized

travel and elimination of the CDST in the

park.

• Major beneficial improvements, as compared

to alternative A, in YNP and GTNP as a

result of the nighttime closure and the

overall elimination of oversnow travel on

north and west side of YNP and the CDST.

• Minor to moderate improvements (at

existing use levels) due to backcountry

closures.

• Improvements would be major and

beneficial, as compared to alternative A, in

the parks due to the elimination of all

potential snowmobile accidents,

implementation of park- wide mass transit

system. And removal of wheeled vehicle

traffic from Colter Bay to Flagg Ranch.

Geothermal Resources

• Minor adverse long term impacts to

geothermal features near groomed roads,

around destination areas, and near winter

trails in the backcountry.

• As in alternative A minor adverse impacts

would occur near staging areas, roads,

destination areas, and near winter trails.

• Adaptive management provisions would

mitigate these effects over the long term.

• Minor incremental long-term degradations

to, and in some cases, permanent loss of

certain features because of increased access.

• General continued adverse impacts as in A

for features near existing groomed routes

and facilities.

• As in alternative A minor adverse impacts

would occur near staging areas, roads,

destination areas, and near winter trails.

• Adaptive management provisions would

mitigate these effects over the long term.

• Elimination of human access to backcountry

and along the north and west road segments

of YNP would greatly decrease potential

impacts.

• Negligible to minor improvements (over

alternative A) due to mass transit and

enhanced visitor awareness programs.

• As in alternative A, minor adverse impacts

would occur near staging areas, roads,

destination areas and near winter trails.

• Adaptive management provisions would

mitigate these effects over the long term.

Water and Aquatic Resources

• Deposition into snow pack would continue

to occur from two-cycle engine emissions

along groomed park roads in YNP and

GTNP.

• Continued high risk of adverse effects on

water quality, wetlands, and aquatic

resources where oversnow motorized use

closely parallels rivers and other bodies of

water (22% of the groomed trail system and

on the frozen surface of Jackson Lake).

• Protection through the monitoring and

scientific studies provisions. If adverse

effects occur that cannot be mitigated, the

activity specifically causing the effect would

be terminated.

• Moderately decreases the risk of adverse

effects on water quality, wetlands, and

aquatic resources where oversnow motorized

use closely parallels rivers and other bodies

of water (high-risk segments along the

Madison and Firehole Rivers). Vehicle miles

traveled on high-risk segments reduced by

65%.

• Minor improvements on the effects from

pollution deposited in the snow by selling

ethanol-blend fuels and low-emission

lubricants.

• Moderately decreases the risk of adverse

effects on water quality, wetlands, and

aquatic resources where oversnow motorized

use closely parallels rivers and other bodies

of water (high risk segments along the

Madison and Firehole Rivers). Vehicle

miles traveled on high-risk segments reduced

by 62%. Snowmobiles phased out from

Jackson Lake.

• Slightly decreases the risk of adverse effects

on water quality, wetlands, and aquatic

resources where oversnow motorized use

closely parallels rivers and other bodies of

water (high risk segments along Yellowstone

Lake). Vehicle miles traveled on high-risk

segments reduced by 14%, no snowmobiles

on Jackson Lake.

• Same as Alternative A for YNP.

• In GTNP, eliminates risk of pollutants

entering Jackson Lake.

• Protection through the monitoring and

scientific studies provisions. If adverse

effects occur that cannot be mitigated, the

activity specifically causing the effect would

be terminated.

• Greatly decreases the risk of adverse effects

on water quality, wetlands, and aquatic

resources where oversnow motorized use

closely parallels rivers and other bodies of

water (high-risk segments along the

Madison, Firehole, Gardner and Gibbon

Rivers and Jackson Lake). Vehicle miles

traveled on high-risk segments reduced by

74%. All motorized use eliminated from

Jackson Lake.

• Greatly decreases the risk of adverse effects

on water quality, wetlands, and aquatic

resources where oversnow motorized use

closely parallels rivers and other bodies of

water (high risk segments along the Madison,

Firehole, Gardner and Gibbon Rivers).

Vehicle miles traveled on high-risk segments

reduced by 84%. All motorized use

eliminated from Jackson Lake.

• Protection through the monitoring and

scientific studies provisions. If adverse

effects occur that cannot be mitigated, the

activity specifically causing the effect would

be terminated.
CHAPTER II

ALTERNATIVES INCLUDING THE PROPOSED ACTION

68
ALTERNATIVE A

No Action ALTERNATIVE B ALTERNATIVE C ALTERNATIVE D ALTERNATIVE E ALTERNATIVE F

ALTERNATIVE G

Preferred Alternative

Wildlife - Ungulates

• Effects of groomed surfaces and plowed

roads on animal movements - unknown to

what extent any beneficial effects outweigh

negative effects.

• Effects related to displacement and

fragmentation are minor to moderate,

adverse, and short-term.

• Risk of collisions with snowmobiles is

negligible, adverse, and short-term.

• Risk of collisions with wheeled vehicles is

minor, adverse, and short-term.

Effects of nonmotorized use – adverse, minor

and short-term.

• Effects of unregulated backcountry

nonmotorized use on displacement from

preferred habitats – adverse, moderate and

short-term. Impacts to bighorn sheep in

GTNP would be moderate to major and longterm if no mitigation is applied.

• Effects from visitor use of winter support

facilities on displacement would be adverse,

minor, and short-term.

• Effects related to groomed roads would

decrease due to the plowing of the road from

West Yellowstone to Old Faithful. Plowing

may increase road-kill mortalities, but

implementation of mass transit would

ameliorate effects.

• Effects related to snowmobiles would

decrease in YNP. In GTNP, separation of

the CDST from the roadway may increase

collisions and displacement effects.

• Effects related to nonmotorized use would

be negligible; additional routes would not be

located in areas critical to wildlife.

• Backcountry uses in certain winter ranges

would be restricted or prohibited in YNP,

thus effects would decrease and become

negligible to minor. Impacts to bighorn

sheep in GTNP would remain the same –

moderate to major and long-term.

• Adaptive management would be employed

to adjust management should impacts to

wildlife be demonstrated through ongoing

monitoring and research.

• Effects on wildlife associated with oversnow

and wheeled vehicles increase. Plowing of

the road from Yellowstone to Old Faithful to

accommodate private vehicles and the

establishment of a groomed snowmobile trail

from GTNP’s south boundary to Moran

along the eastern park boundary may

negatively impact ungulates, especially on

limited winter range in GTNP. The periodic

diversion of the CDST near Jackson Lake

could impact moose.

• Effects related to nonmotorized activities

remain the same as Alternative A, but may

slightly increase because more opportunities

are provided. Moose may be impacted near

the Gros Ventre River in GTNP.

• Effects related to backcountry use would

remain the same as Alternative A.

• More winter facilities are proposed;

including campsites in YNP – thus

associated effects would increase.

• Effects of groomed roads and snowmobiles

would decrease in both parks. In GTNP, no

opportunities for snowmobile use of

ungroomed trails would exist.

• Effects related to plowed roads and wheeled

vehicles would remain the same in YNP and

would decrease in GTNP because the road

from Colter Bay to Flagg Ranch would not

be plowed.

• Effects of unregulated backcountry

nonmotorized use in YNP on all ungulate

species would be negligible to minor due to

limitations on backcountry use and closure

of the E. Entrance. In GTNP, effects of

nonmotorized use on ungulates may increase

because more use would be expected in areas

where snowmobiling would now be

prohibited (e.g., Antelope Flats).

• Overall, this alternative decreases the effects

on ungulates relative to Alternative A.

• Miles of groomed surface in GTNP greatly

decreased, eliminating snowmobile use and

its effects, from most of the park. Moose

would benefit in GTNP by the elimination of

the CDST. Effects would be much lower in

magnitude than in Alternative A. Effects in

YNP would be the same as Alternative A.

• Effects of nonmotorized use in GTNP would

decrease in the Antelope Flats area, thus

benefiting ungulates near important winter

range in the park.

• Effects of unregulated backcountry

nonmotorized use in YNP on all ungulate

species would negligible to minor due to

limitations on backcountry use.

• Overall, the effects on ungulates are

generally the same (YNP) or much less than

Alternative A (GTNP).

• Adaptive management would be employed

to adjust management should impacts to

wildlife be demonstrated through ongoing

monitoring and research.

• Effects of groomed surfaces and oversnow

motorized use are negligible. In YNP,

closing the west side of the park protects

important ungulate habitat.

• Miles of groomed surface in GTNP greatly

decrease, effectively eliminating

snowmobile use, and its effects, from most

of the park. Moose would benefit in GTNP

by the elimination of the CDST.

• In YNP, all nonmotorized use in the

backcountry is prohibited, thus eliminating

all effects associated with off-trail travel.

• Overall effects would be much lower in

magnitude than in Alternative A.

• The effects of groomed surfaces would be

less than Alternative A in GTNP. Risk of

collision from oversnow vehicles would be

nearly eliminated in all parks due to the

prohibition on snowmobiling and late night

travel. Moose would benefit in GTNP by the

elimination of the CDST.

• Mass transit would greatly reduce vehicle

miles traveled and allow for the use of

trained drivers. Consequently there would be

the ability to control where and when stops

are made. This feature would potentially

benefit all species.

• Effects related to plowed roads would be the

same as Alternative A for YNP, and

decreased in GTNP due to the elimination of

wheeled vehicles north of Colter Bay.

• In all parks, restrictions on backcountry

travel would minimize effects associated

with off-trail travel. Effects on bighorn sheep

in GTNP would be eliminated because

important sheep habitats would be closed to

winter use.

• Adaptive management would be employed to

adjust management should impacts to

wildlife be demonstrated through ongoing

monitoring and research.

Wildlife – Threatened and Endangered Species

• Effects of groomed surfaces on lynx

unknown; negligible to major depending

upon lynx abundance, distribution.

• Displacement effects of oversnow vehicles

are adverse, negligible, and short-term.

• Risk of collision with wheeled vehicles

negligible to minor for grizzly bears, wolves.

• Effects of nonmotorized use: adverse,

negligible, short-term on bald eagles; no

effect on grizzly bears; no known effect on

lynx, wolves.

• Effects of unregulated backcountry

nonmotorized use: adverse, minor, and shortterm on bald eagles; adverse, negligible,

short-term on grizzly bears; no known effect

on lynx and wolves.

• Effects of winter support facilities: adverse,

negligible, short-term on grizzly bears;

adverse, minor, short-term on wolves.

• Effects would be generally as stated for

ungulates.

• Impacts to lynx may increase in GTNP

because some of the new groomed routes are

in potential lynx habitat (e.g., Two Ocean

Lake, and diversions of the CDST).

• The new snowmobile route in GTNP may

displace ungulates, and consequently

wolves, from the southeastern part of the

park.

• The extension of the winter use season from

the S. Entrance to West Thumb, combined

with increased winter support facilities may

result in more grizzly bear-human conflicts

as bears emerge from hibernation.

• Closure and elimination of use on the road

from Fishing Bridge to the E. Entrance in

YNP would generally benefit all species

actively using habitat on the entire east side

of the park.

• Most other effects are generally the same as

Alternative A with the exception of the

elimination of unregulated backcountry use

in YNP, which decreases effects, and the

development of warming huts at Jenny Lake

which may increase effects on lynx.

• Slightly decreases the potential effects

compared to Alternative A. The elimination

of snowmobiling from most of the GTNP

would reduce effects associated with packed

trails and displacement; restrictions on

backcountry travel in YNP may decrease

displacement effects associated with off-trail

travel.

• Adaptive management would be employed

to adjust management should impacts to

wildlife be demonstrated through ongoing

monitoring and research.

• The closure of the winter season after 1

March would minimize the potential for

bear-human confrontations and conflicts that

could occur after the emergence of grizzly

bears in the spring.

• Closure of the roads from W. Entrance and

Mammoth to Old Faithful would generally

benefit listed species habitats on the entire

west side of YNP.

• In all parks, if protected species activity is

detected, park managers can close the area to

human activity to mitigate disturbance.

• Potential effects would be the same or less

than Alternative A.

• Effects related to oversnow vehicles on

groomed roads decrease, a potential benefit

to all species. Most visitors would be

traveling on NPS-managed snowcoaches

having the ability to control where and when

stops are made.

• Use of snowcoaches could continue to

displace lynx as routes pass through lynx

habitat, but effects of snowcoaches would be

less than those of snowmobiles being fewer

in number, slower, and quieter.

• Effects related to plowed roads may decrease

impacts to wolves/lynx because wheeled

vehicles eliminated from Colter to Flagg.

• Earlier opening increases potential for

grizzly/human conflicts in YNP. Restrictions

in backcountry areas would mitigate impact.

• Effects of backcountry travel decrease.

• Adaptive management used to adjust

activities if impacts to wildlife are found.

Wildlife –Species of Special Concern

• Effects of groomed surfaces negligible.

• Displacement effects of oversnow vehicles

would be negligible to minor (swans in

YNP).

• Effects of plowed roads on collisions and

displacement would be negligible.

• Effects of nonmotorized use in the front

country – negligible (wolverines, sagebrush

lizard) to minor (swans). In swan habitat, use

may cause minor, short-term displacement

and avoidance.

• Effect of winter support facilities would be

negligible to minor.

• Effects would be generally as stated for

ungulates.

• Effects of motorized wheeled vehicles

increase in YNP and effects of snowmobiles

increase in GTNP. Swans may be affected

in YNP as a result of private vehicles

stopping near open water habitats.

• Effects of nonmotorized activities in the

front and backcountry are generally the same

as Alternative A.

• Effects related to huts increase because the

number of proposed huts increases.

• The elimination of unregulated backcountry

use in YNP may decrease associated effects.

• Closure of the E. Entrance in YNP

eliminates the need for avalanche control

and thus may benefit wolverines. This

closure and elimination of use on the road to

Fishing Bridge would generally benefit

species actively using habitat on the entire

east side of the park.

• Other effects generally the same as

Alternative A.

• Effects the same as in alternative A.

• Adaptive management would be employed

to adjust management should impacts to

wildlife be demonstrated through ongoing

monitoring and research.

• Closure of the roads from W. Entrance and

Mammoth to Old Faithful would generally

benefit habitats on the entire west side of

YNP, and potential effects on trumpeter

swans would be eliminated in those areas.

• Effects in GTNP would be lowered due to

the virtual elimination of snowmobile use.

• If protected species activity is known to

occur in an area, park managers can close the

area to human activity to mitigate

disturbance.

• For all parks, overall effects are the same or

less than Alternative A.

• Effects related to oversnow motorized

vehicles are reduced because no

snowmobiles would be permitted in the

parks.

• Effects related to groomed surfaces would

decrease in GTNP benefiting martens.

• The majority of visitors would be traveling

on NPS-managed snowcoaches, and there

would be the ability to control where and

when stops are made, benefiting all species.

• Effects associated with backcountry use are

reduced from those in Alternative A. Bighorn

sheep closures may benefit wolverines.

• Adaptive management would adjust activities

should impacts to wildlife be demonstrated.

Natural Soundscapes

• Current non-natural sounds impact the

soundscape in the three park units.

• Moderate to major adverse effects occur

because vehicles are audible over more than

200,000 acres, and they are audible more

than 50% of the time over more than 26,000

acres. Audibility for more than 50% of the

time is greatest relative to the W. Entrance to

Old Faithful route and from Moran to GTNP

south entrance.

• The average sound level is highest along

these routes and on Jackson Lake.

• Elimination of oversnow vehicles on the

road from W. Entrance to Old Faithful

would moderately reduce soundscape

impacts.

• Lowering all snowmachine sound emissions

from 78 dB to 70 dB would reduce the area

in which vehicles are audible more than 50%

of the time by 38%. When implemented this

would result in moderate beneficial effects.

• Sound levels 4000 feet distant from travel

ways would be reduced by a third, overall.

• Elimination of oversnow vehicles on the

road from W. Entrance to Old Faithful

would moderately reduce soundscape

impacts.

• The area in which vehicles are audible more

than 50% of the time would be increased by

22% resulting in moderate to major adverse

impacts on the soundscape.

• Sound levels 4000 feet distant from travel

ways would be slightly reduced overall

resulting in negligible improvements.

• Reduction in snowmobile sound emissions

from 78 dB to 60 dB would moderately

reduce impacts on the soundscape.

• Compared to quiet background conditions,

this alternative would reduce by 44% the

area in which vehicles are audible more than

50% of the time. Overall this alternative

would result in moderate to major beneficial

effects on the natural soundscape.

• Sound levels 4000 feet distant from travel

ways would be moderately reduced by about

half.

• Compared to quiet background conditions,

this alternative would reduce the area in

which vehicles are audible at all by 16%.

This reduction is due to the elimination of

winter motorized use on Jackson Lake.

• The alternative would not change the area in

which vehicles are audible more than 50% of

the time.

• Sound levels 4000 feet distant from travel

ways would be slightly reduced overall

resulting in negligible improvements.

• In the absence of mitigating use limits, this

alternative would increase by 24% the area

in which vehicles are audible more than 50%

of the time. This is a result of the shifting of

use from closed segments to open segments

on the south and east side of YNP.

• Sound levels 4000 feet distant from travel

ways would be reduced by about a third,

overall.

• Elimination of snowmobile sound emissions,

and limiting snowcoach dBAs in the short

term to 75, long term to 70, would

moderately reduce impacts on the

soundscape.

• Compared to quiet background conditions,

would decrease by 47% the area in which

vehicles are audible more than 50% of the

time.

• Sound levels 4000 feet distant from travel

ways would be slightly reduced overall.
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ALTERNATIVE A

No Action ALTERNATIVE B ALTERNATIVE C ALTERNATIVE D ALTERNATIVE E ALTERNATIVE F

ALTERNATIVE G

Preferred Alternative

Visitor Access & Circulation

• Minor adverse impacts would continue due

to the high cost of current winter access to

YNP’s interior

• Parking at some staging areas is filled to

capacity during peak use times resulting in

minor adverse impacts.

• Some conflict between motorized and

nonmotorized use occurs.

• All areas of the parks currently accessible

under alternative A would remain accessible

under alternative B.

• Visitor capacity would remain at levels equal

to the no-action alternative

• Mass transit shuttle would provide a less

expensive means of winter access resulting

in minor to moderate beneficial effects.

• Moderate long-term beneficial

improvements for safe snowmobile access

on the CDST.

• Grand Loop not available by single means of

transport.

• Although plowed roads would allow for

wheeled vehicle access in YNP, the lack of

available parking at Old Faithful, Madison

and Old Faithful would result in moderate

adverse effects due to an overall reduction in

winter visitor capacities.

• Minor to moderate long-term beneficial

improvements for safe snowmobile access

from Jackson and Dubois to GTNP/Parkway,

and north into YNP.

• Private vehicles would provide a less

expensive means of winter access.

• Grand Loop not available by single means of

transport.

• Minor adverse impacts would continue due

to the high cost of winter access to YNP’s

interior.

• Minor adverse effects would occur to overall

park access because of E. Entrance closure

in YNP. Winter season visitors using the E.

Entrance represent 3% of winter season

visitation or approx. 4,100 visitors

• Negligible adverse effects to park access

would occur in GTNP. Moderate long-term

beneficial improvements for safe

snowmobile access on the CDST.

• Minor adverse impacts would continue due

to the high cost of winter access to YNP’s

interior.

• Short-term access in YNP, same as in

Alternative A. Long-term effects are

unknown and would depend on future

management decisions related to area

closures.

• Access to GTNP in general would not

change, although modes of travel in some

areas would change. Motorized access on

Jackson Lake would be eliminated.

• Minor adverse impacts would continue due

to the high cost of winter access to YNP’s

interior.

• Major long-term adverse effect to current

visitor access patterns at YNP due to

elimination of two winter entrances.

• Effects for GTNP would be the same as

alternative E.

• The Grand Loop experience would be

eliminated.

• Minor adverse impacts would continue due

to the high cost of winter access to YNP’s

interior.

•Negligible long-term effects to YNP because

level of access is not altered, only the mode

of travel.

• Minor adverse long-term effects in GTNP

would occur because motorized access on

Jackson Lake would be eliminated.

Visitor Experience

All three park units

• Little or no operational change would occur.

Visitation would be influenced by the method

of transportation available to visitors.

• For visitors who prefer to visit the parks via

snowmobile, the visitor experience would

continue to be highly satisfactory.

• Encounters with park wildlife and scenery

would continue to be primary attractions,

consequently the overall satisfaction of

current winter visitors would remain high.

• Current levels of snowmobile emissions and

sound levels would continue to detract from

critical characteristics of the desired winter

experience for many visitors resulting in

direct short-term major adverse impacts on

visitor experience.

• The perceived unsafe behavior of others and

the occurrence of visitor conflicts would

continue to have direct short-term minor to

moderate adverse effects on the experience of

some users.

• Current motorized use would continue to

deter some user groups from visiting or

returning to the parks.

All three park units

• The adaptive management provisions could

result in sections of the park being closed to

protect resources/values. Visitor

opportunities currently afforded in those

areas would be eliminated, resulting in direct

short-term adverse effects to desired winter

visitor experience. Long-term protection of

these resources would be a major beneficial

effect by providing for future enjoyment.

• The reduction of snowmobile emissions and

sound levels would in the long term greatly

enhance opportunities for solitude, clean air,

and natural quiet. This would result in

moderate to major beneficial improvements

to the desired visitor experience.

YNP

• Major to moderate adverse effects on desired

winter experience for persons who wish to

access the park via the W. Entrance via

oversnow transport.

• Plowed road from W. Entrance to Old

Faithful could create berms of snow resulting

in moderate adverse effects on opportunities

to view scenery.

• Opportunities to view wildlife and scenery as

a solitary experience would be eliminated on

the W. Entrance Road for those persons who

are limited to motorized travel.

• Would provide an opportunity for the winter

experience at Old Faithful which has not

been available to park visitors who do not

wish to or who cannot afford to ride a

snowmobile or snowcoach.

GTNP & Parkway

• Moderate beneficial changes relating to

safety by separating user groups within the

park, and by improving groomed surfaces.

• Moderate beneficial improvement due to

increased availability of information,

interpretation, and winter programs.

YNP

• Major to moderate adverse effects on desired

winter experience, affecting the current

winter visitors who access the park via the

W. Entrance using oversnow transport.

• The creation of snow berms along plowed

roadways could cause moderate adverse

effects to scenery viewing opportunities.

• The addition of motorized and nonmotorized trails would increase opportunities

for winter experiences and would result in

direct moderate beneficial improvements.

• Affects on opportunities for solitude, clean

air, and quiet (except during the late season)

would be minor to moderate and adverse,

except at W. Entrance.

• In the vicinity of Old Faithful opportunities

for clean air would be moderate and

beneficial.

• Moderate to major adverse effects would

occur due to the complexities of park travel.

• Visitors, who are unable, cannot afford, or

do not wish to ride a snowmobile or

snowcoach would have access via private

automobile to Old Faithful.

GTNP & Parkway

• A full range of winter activities would be

available to enhance opportunities for

wildlife and scenery viewing.

• Minor beneficial changes in safety due to

improvement of the CDST.

• Minor adverse effect in locating motorized

and nonmotorized uses in close proximity.

• Opportunities for use on groomed surfaces

would increase.

• Minor to moderate beneficial effect to visitor

experience due to increased availability of

information and trailside facilities.

• Major adverse effect to opportunities for

quiet and solitude. Opportunities to

appreciate clean air also adversely affected.

All three park units

• The reduction of snowmobile emissions and

sound levels would, in time, result in

moderate to major beneficial improvements

in opportunities for solitude, clean air and,

natural quiet.

• Minor beneficial effect to visitor experience

due to greatly increased availability of

information, interpretation, and winter

programs.

YNP

• The increase in trail opportunities would

provide minor to moderate beneficial effects

for all user groups.

GTNP & Parkway

• Minor to negligible adverse effects to

opportunities for wildlife and scenery

viewing.

• Major beneficial improvements relating to

safety by separating user groups within the

park.

• Widening the groomed surfaces of the CDST

and removing adjacent wheeled vehicle

traffic from Colter Bay to Flagg Ranch

would be a moderately beneficial effect.

All three park units

• The adaptive management provisions could

result in sections of the park being closed to

protect resources/values. Visitor

opportunities currently afforded in those

areas would be eliminated, resulting in direct

adverse effects to desired winter visitor

experience. Long-term protection of these

resources would be a major beneficial effect

by providing for future enjoyment.

YNP

• Negligible to moderate beneficial short-term

improvements in opportunities to appreciate

clean air, quiet, and solitude from the

implementation of the standards set by the

FACA committee.

GTNP & Parkway

• Wildlife and scenery viewing would remain

unchanged for nonmotorized users and

automobile occupants.

• There would be major beneficial

improvements relating to safety by

eliminating snowmachines as a source of

motor vehicle accidents, except on Grassy

Lake road.

• There would be major adverse effects on

opportunities to participate in oversnow

motorized activities.

• There would be major beneficial effects

relative to opportunities for quiet and solitude

by eliminating snowmobiles- except on the

Grassy Lake road.

• Moderate to major improvements in air

quality would result in greater opportunities

to appreciate clean air.

YNP

• The elimination of winter opportunities on

the road segments connecting the West and

North Entrances with Old Faithful would

result in major adverse effects on the desired

winter visitor experience.

• If winter use increases in other areas of the

parks minor effects are expected on visitor

experience in those areas.

GTNP & Parkway

• Same as alternative E except for decline in

experiential values around Flagg Ranch due

to possible displaced motorized oversnow

use from YNP.

All three park units

• The adaptive management provisions could

result in sections of the park being closed to

protect resources/values. Visitor

opportunities currently afforded in those

areas would be eliminated, resulting in direct

adverse effects to desired winter visitor

experience. Long-term protection of these

resources would be a major beneficial effect

by providing for future enjoyment.

• Opportunities to view wildlife and scenery as

a solitary experience would be eliminated for

those persons who are limited to motorized

travel.

• There would be major beneficial changes

relating to safety by eliminating the

possibility of snowmobile related motor

vehicle accidents.

• There would be a minor to moderate

beneficial effect to visitor experience due to

increased availability of information,

interpretation and winter programs.

• Opportunities to appreciate clean air would

be greatly improved. Where oversnow

motorized use occurs, via snowcoach, quiet

and clean air would be facilitated by

improved motorized technology.

•The elimination of snowmobiles would result

in major adverse effects to the experiences

of visitors who prefer this mode of travel.

•There would be a major beneficial effect

relative to opportunities for quiet and

solitude, for nonmotorized visitors.

*SUMMARY STATEMENTS ABOVE ARE ABBREVIATED AND TAKEN OUT OF CONTEXT TO PROVIDE A QUICK COMPARISON BY ELEMENT.

THE READER IS ENCOURAGED TO REVIEW THE SUPPORTING ANALYSIS IN CHAPTER IV.
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SUMMARY OF ALTERNATIVES AND EFFECTS

73

Figure 2. Alternative A for YNP.

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SUMMARY OF ALTERNATIVES AND EFFECTS

75

Figure 3. Alternative B for YNP.

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SUMMARY OF ALTERNATIVES AND EFFECTS

77

Figure 4. Alternative C for YNP.

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SUMMARY OF ALTERNATIVES AND EFFECTS

79

Figure 5. Alternative D for YNP.

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SUMMARY OF ALTERNATIVES AND EFFECTS

81

Figure 6. Alternative E for YNP.

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SUMMARY OF ALTERNATIVES AND EFFECTS

83

Figure 7. Alternative F for YNP.

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SUMMARY OF ALTERNATIVES AND EFFECTS

85

Figure 8. Alternative G for YNP.

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SUMMARY OF ALTERNATIVES AND EFFECTS

87

Figure 9. Alternative A for GTNP and the Parkway.

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SUMMARY OF ALTERNATIVES AND EFFECTS

89

Figure 10. Alternative B for GTNP and the Parkway.

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SUMMARY OF ALTERNATIVES AND EFFECTS

91

Figure 11. Alternative C for GTNP and the Parkway.

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SUMMARY OF ALTERNATIVES AND EFFECTS

93

Figure 12. Alternative D for GTNP and The Parkway.

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SUMMARY OF ALTERNATIVES AND EFFECTS

95

Figure 13. Alternatives E and F for GTNP and the Parkway.

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SUMMARY OF ALTERNATIVES AND EFFECTS

97

Figure 14. Alternative G for GTNP and the Parkway.

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99

CHAPTER III

AFFECTED ENVIRONMENT

INTRODUCTION

This chapter describes the environment of the area that could be affected by the

alternatives being considered. This description is intended to present only the

information necessary to understand the effects of the alternatives presented in Chapter

IV. As such, data and analyses are commensurate with the importance of the impacts.

The importance of an impact is reflected largely by its relationship to a major issue, as

documented in the purpose and need section.

The cost of current winter use management in the three park units is not expressly

discussed in this chapter. Since this topic may be of interest to some readers, cost

information is included in Appendix F.

MANDATORY TOPICS

Council on Environmental Quality (CEQ) regulations (40 CFR part 1500) and National

Park Service (NPS) policy (NPS DO-12) require that certain topics be addressed in every

Environmental Impact Statement (EIS). The following discussion addresses those topics

in one of two ways: 1) it provides a rationale for dismissing the topic from further

consideration; or 2) it directs the reader to the appropriate section of the document where

further information on the topic is provided.

• Possible conflicts between the proposed action and land use plans, policies or controls

for the area concerned (including local, state, or Indian tribes) (1502.16, 502.2(d), and

the extent to which the NPS will reconcile the conflict. See Direct, Indirect, and

Cumulative Effects on Adjacent Lands, Chapter IV.

• Energy requirements and conservation potential (1502.16). Operations for all three park

units use energy to maintain park facilities and operate motor vehicles throughout the

winter. All alternatives propose a level of mechanized winter recreation. The effects of, or

on, those requirements do not vary substantially by alternative. For this reason, this topic is

dismissed from further consideration.

• Natural or depletable resource requirements and conservation potential (1502.16). The

range of alternatives and the purpose and need of this document are fully within the scope

of NPS mandates and policies. No natural or depletable resources would be extracted

under this plan nor will natural resource commodities be produced. Therefore, this topic is

dismissed from further consideration.

• Urban quality, historic and cultural resources, and design of the built environment

(1502.16). See Cultural Resources, Chapters III and IV, and Consultation and

Coordination, under State Historic Preservation Offices, Chapter I.

• Socially or economically disadvantaged populations (Executive Order (EO) 12898). See

Socioeconomics, Chapters III and IV.
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AFFECTED ENVIRONMENT

100

• Wetlands and floodplains (1508.27). Floodplains are not impacted by winter use activities

in the parks. See Impact Topics Dismissed, Chapter III. Wetlands are discussed in

Chapters III and IV, under Water Resources.

• Prime and unique agricultural lands (1508.27). Private land in-holdings exist within the

boundaries of Grand Teton National Park (GTNP). None of the actions proposed in the

range of alternatives would affect such lands, access to them, or their agricultural

properties. Therefore, this topic is dismissed.

• Endangered or threatened plants and animals and their habitats (1508.27). See

Federally Protected Species and Species of Special Concern in the Wildlife section,

Chapters III and IV.

• Important scientific, archeological, and other cultural resources including historic

properties listed or eligible for the National Register of Historic Places (1508.27). See

Cultural Resources, Chapters III and IV.

• Ecologically critical areas, wild and scenic rivers, or other unique natural resources

(1508.27). The range of alternatives and the purpose and need are fully within the scope of

NPS mandates and policies. No action proposed in the range of alternatives would affect

the eligibility or designation of a wild and scenic river or wilderness area. See also Impact

Topics Dismissed, Chapter III. Other unique, natural resources such as geothermal features

are presented in Chapters III and IV.

• Public health and safety (1508.27). See Air Quality and Public Health, and Public Safety,

Chapters III and IV.

• Sacred sites (EO 13007) and Indian trust resources (ECM95-2). See Cultural Resources,

Chapters III and IV.

IMPACT TOPICS DISMISSED

Floodplains

Executive Order 11988 and NPS policy require that impacts on floodplains be considered

in NPS undertakings. The intent of the order and guidelines is to provide for human

safety and protect floodplain functions by preventing development in 100-year

floodplains. Floodplains for all three units are well defined, although the Federal

Emergency Management Agency has not published national flood insurance rate maps

for these areas. There are no actions proposed in the Plans/EIS that would occur in or

encroach upon floodplains, and all actions would occur during the winter months when

there is little concern for flooding. With this finding, no further analysis of floodplains is

necessary.

Black Bear (Ursus americanus)

Black bears range throughout most of North America. One primary concern associated

with human development in occupied bear habitat is the availability of food attractants.

Bears that become conditioned to human foods and garbage are often the target of

management actions and usually are eliminated (Herrero 1985).

It has not been demonstrated that existing winter recreation activities in the parks affect

black bears. Destruction of den sites or den habitat does not appear to be an issue in the

Greater Yellowstone Area (GYA). Bears are not being disturbed while they are

preparing or occupying den sites (Reinhart and Tyers 1999). The main concern is the

potential for bear/human conflicts and displacement of bears while they are foraging

during the pre-denning and post-emergence periods. The current winter recreation
MID-SIZED CARNIVORES

101

season in the parks precludes most bear activity and most risks of bear/human conflicts.

Therefore, black bears are not addressed further in this document.

Mid-Sized Carnivores

Mid-sized carnivores not addressed further in this analysis include the bobcat (Felis

rufus), red fox (Vulpes vulpes), and coyote (Canis latrans). These species are not

considered rare or in need of special protection in the parks. Other mid-sized carnivores,

including the river otter (Lutra canadensis), wolverine (Gulo gulo), fisher (Martes

pennanti), and American marten (Martes americana), are considered species of special

concern in the parks, and are discussed under Species of Special Concern. The

threatened Canada lynx (Lynx canadensis) is addressed under Federally Protected

Species.

Subnivian Fauna

Subnivian fauna are small mammals that live under snow during winter, including

shrews, voles, pocket gophers, and mice. They are active throughout the year, eat a

variety of plant and animal foods, and generally occupy habitats on or below the ground.

They are important prey species for a variety of birds and larger mammals, including the

American marten (Cherry and Kratville 1999). Although no significant impacts on

populations of subnivian fauna are expected to occur, the potential effect of localized

reductions in these mammals because of snow compaction may affect martens. An

assessment of this impact is found under Species of Special Concern for each alternative.

In general subnivian fauna are abundant residents of the parks, and any potential loss of

habitat caused by road grooming or plowing operations is compensated for by the vast

amount of unroaded area found in the parks. Therefore, subnivian fauna are not directly

addressed further in this EIS.

Birds

Most bird species are not addressed further in this analysis because they only occur in the

parks in the summer or their habits are not considered threatened by winter recreation.

This includes peregrine falcons (Falco peregrinus), a species of special concern that was

removed from the endangered species list in 1999, but is dismissed as an impact topic.

Peregrines’ seasonal occurrence precludes them from being affected by winter recreation.

Whooping cranes (Grus americana), classified as experimental, nonessential under the

ESA, are also not addressed because of their seasonal occurrence. A discussion of the

whooping crane’s status can be found in the biological assessment (BA) published

concurrently with this document. Bald eagles (Haliaeetus leucocephalus) are discussed

under Federally Protected Species, and trumpeter swans (Cygnus buccinator) are

discussed under Species of Special Concern.

Several species of birds that occur in the parks may be affected by human recreational

activities due to increased habituation to human use areas, food, and garbage. The

common raven (Corvus corax), gray jay (Perisoreus canadensis), and Clark’s nutcracker

(Nucifraga columbiana) are especially susceptible to habituation. Habituated wildlife is
CHAPTER III

AFFECTED ENVIRONMENT

102

a widespread, year-round issue. Increased educational opportunities, a feature of all

alternatives discussed in this document, are the best way to combat this problem.

Reptiles

Reptiles that are not affected by winter use are the bull snake (Pituophis catenifer sayi)

and the prairie rattlesnake (Crotalis viridis viridis). All reptiles in the park hibernate and,

therefore, are not directly affected by winter use. Potential indirect effects associated

with water pollution are not a concern because these snakes occur in dry, upland habitats.

See Reptiles and Amphibians and Aquatic Species: Reptiles, Amphibians, and Fish,

Chapter III for a discussion of the other reptiles found in the parks.

Vegetation, including Plant Species of Special Concern and Threatened

Plants

Damage to vegetation from off-trail winter recreation activities has been documented in a

number of studies, including:

• Physical damage to exposed branches and leaders of willows (Salix spp.), sagebrush

(Artemisia spp.), and conifer species (Stangl 1999).

• Decline of grasses and herbaceous plants from snowmobile trails (Wanek 1971).

• Tissue dehydration and microorganism reduction caused by temperature changes

associated with snow compaction (Wanek 1971).

• Soil erosion where compaction by snowmobiles delayed melting during the growing season

(Wanek 1971).

Most documented impacts from snowmobiles occur away from established roads and

trails. In the parks, oversnow motorized activities are limited to roads and along road

margins where motorized use is allowed throughout the year. Because little to no

vegetation exists on these routes, oversnow motorized use would have negligible direct

impact on vegetation (Stangl 1999). Similarly, the effects of snow plowing on

vegetation in the parks (including trees) are considered negligible. Two species of plants

considered to be of special concern are discussed below.

Ross’ bentgrass (Agrostis rossiae) and Yellowstone sand verbena (Abronia ammophila)

are unique to Yellowstone National Park (YNP), and are restricted to very specialized

habitats within the park. These species are of special management concern because of

their rarity and localized occurrences. Ross’ bentgrass is found primarily on marl around

hot springs and geysers near Old Faithful. Despain (1990) theorized that bison or elk

may transport the seeds of Ross’ bentgrass between thermal areas. Because of its highly

localized habitat, this species is probably the vascular plant most vulnerable to extinction

in Wyoming (Clark et al. 1989). Yellowstone sand verbena, a sand obligate, is found

along sandy shorelines of Yellowstone Lake; extensive searches have failed to find it

elsewhere in the park. Little is known of its life history. Winter use is not expected to

affect either species (Whipple, pers. com., 2000).

The threatened Ute Ladies’-tresses orchid (Spiranthes diluvialis) is the only plant listed

under the ESA that may potentially occur in the parks. However, this orchid has never
EXOTIC SPECIES — PLANTS

103

been reported within the parks. Known populations occur in Idaho, Montana, and

Wyoming at elevations lower than the Yellowstone plateau. Therefore, this species is not

addressed.

Exotic Species — Plants

About 200 nonnative plant species are known to occur in the parks (Whipple, pers. com.,

2000). Both parks maintain aggressive exotic weed control programs using an Integrated

Weed Management approach that relies on prevention, early detection and control, and

various control strategies including mechanical, cultural, and chemical. While winter

recreation does not occur during the plant growing season, exotic weed propagation may

occur through ground disturbance associated with winter-use facility construction and

snowmachines that may act as vectors for weed dispersal. If not inspected and cleaned

before entering the park, snowmachines can be a source of weed propagation along park

roads and in park developed areas, though not nearly as significant as vehicles entering

the parks during other seasons. Because all motorized winter use in the parks occurs on

roads or their immediate margins and because of existing aggressive control programs,

no further analysis of the effects of exotic species is included in the Plans/EIS.

Exotic Species — Animals

Mountain Goat (Oreamnos americanus)

Mountain goats were historically found in the mountains of the north coast and the Rocky

Mountains. Through state fish and game agency introductions, their distribution has

expanded both within and outside of their historic range (Varley 1999). Consequently,

although mountain goats were historically absent from the GYA, they currently inhabit

most mountain ranges in the GYA.

Throughout their range, mountain goats inhabit steep, rocky terrain during all seasons of

the year. Winter range habitats include areas close to cliffs, and steep, rocky, south

facing slopes. Winter severity and snow depths seem to be leading causes of mortality of

mountain goats, affecting availability of winter forage and causing stress, susceptibility

to accidents, disease, and parasites (Varley 1999).

While nonnative mountain goats have been known to cause adverse effects to vegetation

elsewhere, there are no known significant impacts to native plant communities in the

parks (Varley 1999). However, it was predicted by Laundre (1990) that goats might

eventually impact native bighorn sheep populations in YNP. Whitfield (1983) reported

that goats might eventually pose a threat to bighorn sheep in GTNP. Although control

efforts are not conducted in the parks, potential impacts to mountain goats are not

assessed in this document.

Bullfrog (Rana catesbeiana)

The introduced bullfrog occurs in the Kelly Warmspring in GTNP. It is a voracious and

prolific predator. Impacts to bullfrogs are not assessed, since the species is considered

undesirable in the park’s ecological environment.
WILDERNESS VALUES

104

Wilderness Values

The scope of the purpose and need for action does not allow consideration of changes in

or alternatives directly affecting proposed or recommended wilderness in the three parks.

Therefore, there are no actions proposed, such as trails, grooming, facility construction,

or motorized use, that would impact wilderness values. During scoping and initial

alternative concept formulation, a number of ideas were proposed along this line, but

they were dismissed as outside the scope of analysis. See Appendix A Coordination and

Consultation for a detailed discussion of how ideas were presented, how they fit into the

EIS alternatives or analyses, and why other ideas were dismissed.

Wilderness values consist of elements that are intrinsic to wilderness, as well as elements

that are experiential and relative to people’s appreciation of wilderness. The analysis

does not avoid the subject of wilderness values entirely. Rather, it considers impacts on

factors like natural quiet, scenic quality, wildlife, and air quality. Such elements are

recognized as important wilderness components, and impacts on them are considered as

disclosure of indirect impacts. Because of this disclosure, and because proposed actions

are overtly designed to avoid impacting proposed and recommended wilderness, this

topic is dismissed from further discussion.

IMPACT TOPICS ADDRESSED

Socioeconomics

The state and county cooperating agencies provided information within their areas of

special expertise: social and economic analysis. Much of this information helps define

the affected environment for socioeconomics.

Regional Economy

The analysis area for the regional economy is a five-county portion of the GYA. It

includes the contiguous counties in Montana, Wyoming, and Idaho surrounding YNP,

GTNP, and the Parkway. The five counties are Fremont in Idaho, Gallatin and Park in

Montana, and Park and Teton Counties in Wyoming (

Figure 15. County map.). This five-county area was chosen to include the parks and

contiguous lands, as well as national forest lands and other nearby lands and communities

that are most often visited by non-local visitors to the area. The following discussion of

the economic characteristics of the affected environment of the five-county GYA

presents average characteristics. While the five counties are all within the GYA, the

individual counties do vary somewhat in their basic economic structure. Most counties

have an economic base dominated by tourism. Characteristics such as unemployment

rates and income
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Figure 15. County map.

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AFFECTED ENVIRONMENT

106

levels also vary between counties within the GYA. The five-county analysis area

represents the counties and communities where most of the economic activity related to

the parks occurs. Individual counties and communities within the GYA are impacted

differently by this park-related economic activity. Small communities adjacent to the

park such as West Yellowstone, Gardiner, or Cooke City are highly dependent on park

visitor spending, while larger communities (such as Bozeman, Montana) derive a much

smaller share of their economic activity from park visitor spending. The following is a

discussion of the socioeconomic characteristics of the affected environment and the

estimates of impacts of alternative management actions on the five-county area. Because

the counties and communities have different economic settings, the impacts of alternative

management actions may differ for the five counties.

Public lands provide the basis for much of the economic activity (recreation, mining,

forestry, and agriculture) that occurs in the five counties. The area’s overall economy has

been changing for more than 20 years. The economy has shifted from a dependence on

commodity extraction to a more diversified economy based on recreation, tourism, and

service industries. For example, between 1969 and 1989, more than 96% of all new jobs

in the larger 17-county GYA area came from sectors other than timber, mining, and

agriculture (Rasker, et al. 1992).

Income

The diversification of the economy in the GYA and growth in the total number of jobs

has helped keep unemployment in the five counties relatively low, an average of 3.8% in

1997. Restructuring the region’s economy from a reliance on extractive industries, which

are declining, to a more diversified blend of the other sectors, which are expanding,

provides a more stable employment base for the region.

Table 13 s ho ws em pl o ym e ntb y e c o nom i cs e c t ori n t hef i vec o un t i e s. M os tj ob s p e r t a i ni ng

t ot he r e c r e a t i ona nd to ur i smi n du st r y ar ef oun d in th er e t a i lt r a d e ands e r v i c e s se c t o r sofa 

c o un t y’ s ec o no m y. The sese c t or sa r e mu c h br oa d e rt h a nr e c r e a t i o n a ndt o ur i sm , andi nc l ud e 

a c t i vi t i e s s uc h a s he a l t hc a r e . Th e set wo se c t o r sa c c o untf or ab out4 2% oft h e ea r ni ngsi n t he 

5- c o unt y ar e a . 

Re t a i l tr a der e l a t i ng tor e c r e a t i o n i nc l ud e sl o dg i nga c c om m od a t i on s, r e st a ur a nt s,so uv e ni r 

sh op s, ve hi c l er e nt a l f i r m s , spo r t i ngg ood s st o r e s, an d r e c r e a t i ona l equ i p m e n t r e n t a lf i r m s. 

T h e s eb us i ne ss e s an d t he i r em pl o ye e s ar ed e p e nd e n tu po n t hevi si t i n g pub l i c . Re c r e a t i o nr e l a t e ds e r v i c e s in c l u degu i d e s,o ut f i t t e r s,t o uror ga ni z e r s, an d o t h e r sw ho se r vi c et h e 

de m a ndso ft hevi si t i n g pub l i c . M a nyo t he r bus i n e ss e sa r e ind i r e c t l ysu pp or t e dbyt he 

r e c r e a t i o n- r e l a t e d ec o no m y,i nc l ud i ngg r oc e r y s t o r e s , aut o r e p a i rs ho ps,a nd co nst r u c t i on 

c o m p a ni e s . Be c a u seoft he wo r l d - r e no wn e d r e c r e a t i on a lr e so ur c e sa va i l a bl et o thep ubl i c 

wi t h i n th eG YA , gr owt h in th e ses e c t or s i s exp e c t e dt o c on t i n ue .
SOCIOECONOMICS

107

Employment

Recreation and tourism are key to the economic viability of the area. Total employment

for the five-county area is shown in Table 13, and the percent allocation of income by

major industry is shown in T a bl e14. Retail trade and services accounted for about 51%

of the five counties’ combined employment. These industry sectors, along with the

government sector, have a strong tie to the region’s resources and are expected to

continue to be important and sustaining segments of the GYA economy.

Table 13. Industry breakdown of employment

(Number of individuals employed for the five-county GYA in 1996).

Industry Five-County GYA Area

Employment

Percent of Total County

Employment

Total farm 3,417 3.62%

Total non-farm 90,947 96.38%

Private 75,814 80.34%

Miscellaneous, agriculture,

and forestry 1,728 1.83%

Mining 1,043 1.11%

Construction 8,149 8.64%

Manufacturing 4,872 5.16%

Transport and utilities 3,235 3.43%

Wholesale 2,624 2.78%

Retail 19,371 20.53%

Insurance and real estate 6,109 6.47%

Services 28,683 30.40%

Government 15,133 16.04%

Source: U.S. Department of Commerce, Bureau of Economic Analysis, Regional Economic Information System, 1998.

Tabl e14. Tot al e ar ni ngs by m aj orindust r y f ort hre e - st at ear e a and f orf i ve - c ount y GYA.

Industry Three-State Area

(MT, ID, WY) Five-County GYA Area

Mining and construction 12.41% 13.68%

Manufacturing 12.23% 6.33%

Other†13.84% 9.32%

Retail trade 11.14% 14.31%

Finance, insurance, and real estate 5.13% 6.31%

Services 23.26% 28.16%

Government 18.88% 19.30%

Farm 3.12% 2.02%

Source: U.S. Department of Commerce, Bureau of Economic Analysis Regional Economic Information System, 1998.

†

Includes agriculture services, forestry, and fisheries; transportation and public utilities; and wholesale trade.
CHAPTER III

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108

Recreation Sector and Park Visitors

Recreational use of the affected environment is a key component of the area’s economy.

In winter 1998-99 YNP and GTNP visitors from outside Montana, Wyoming, and Idaho

spent an average of $1,129 during their trips. Of this amount, $608 per person was spent

in the GYA (Duffield and Neher 2000). Winter visitors to the park from outside the

GYA spend significantly less than out-of-state visitors, with $210 per trip being spent

within the GYA. The expenditure estimate for nonresident winter visitors from the 1999

winter visitor survey, cited above, is similar to those from other studies. A 1993-95

Wyoming Snowmobile Assessment for the Wyoming Department of Commerce

estimated nonresident snowmobile expenditures at $774 per person per trip (Taylor et al.

1995).

Winter visitation to YNP and through the GTNP Moran and Moose Entrances from

December through March 1998-99 is estimated at 117,666 recreational visits (YNP

Planning Office and GTNP Superintendent’s Office). Considering re-entry on multi-day

trips, this implies 88,250 recreational trips.

Recreation on national park and national forest lands within the GYA is an important

component of total GYA economic activity. For example, within Fremont County,

Idaho, which adjoins the parks, over 400 miles of snowmobile trails are groomed on a

regular basis. These trails include links to Flagg Ranch and West Yellowstone. The

county estimates there are 300,000 snowmobile user days each year with an additional

40,000 days of other winter recreation. Fremont County further estimates that 560 jobs

and $5 million in payroll within the county are directly related to year-round recreation

(Director of Fremont County Parks and Recreation, Tamra Cikaitoga, pers. com., 1999).

Winter recreation, and associated visitor expenditures are substantial within the fivecounty area. In the context of total annual recreation-related expenditures in the GYA,

winter recreational expenditures are far less important than non-winter expenditures.

This is because only 4% to 5% of annual recreational visitation to YNP occurs from

December through March.

In the context of the total GYA economy, expenditures by winter park visitors (and the

additional economic activity that spending indirectly generates or induces) are a small

portion of total GYA annual economic output. The direct, indirect, and induced

expenditures generated in the GYA by nonresidents visiting the parks in the winter

months are estimated at about $63 million. In the context of the $5.7 billion dollar

annual output of the 5-county economy, this represents only 1.1% of the total (Minnesota

IMPLAN Group 1996).

The importance of winter visitation to local economic activity within the GYA varies

from county to county and community to community. Communities located directly

adjacent to the park derive a much larger portion of their total economic output from park

visitor expenditures than the GYA economy as a whole.
SOCIOECONOMICS

109

The West Yellowstone tourism tax data for the past decade shows that tourism spending

in the town has grown substantially. Between 1989 and 1999 total annual taxable tourist

spending increased at an average annual rate of 10%. Tourist spending during the winter

months of December, January, February, and March has remained at a relatively stable

proportion of annual spending over the past ten years (between 25% and 28%). Over that

period, winter tax receipts have grown at an annual rate of 10.9%. While the ten-year

average growth rate of the winter tourism tax receipts in the town has been substantial, it

should be noted that the year-to-year growth rates in that period have ranged from an

increase of 25.6% to a decrease of 1.6%. Even within this relatively fast growing tourist

economy there is substantial year-to-year fluctuation in sales.

A 1994 report on snowmobiling in Montana found nonresidents spent about $40 million

annually in the state, and 75% of those nonresidents spent time in or near West

Yellowstone (Sylvester and Nesary 1994).

A 1997 study commissioned by the NPS estimated the economic effects of the winter

1995–96 government shutdown on economies adjacent to park units (Neher, et al. 1997).

YNP and West Yellowstone served as a case study. The NPS report estimated a

statistical relationship between YNP West Entrance and West Yellowstone sales tax

collections from January 1989 through February 1996. The study found a significant

difference between estimated tourist expenditures in West Yellowstone for the winter and

non-winter periods. For the winter months December through March, it was estimated

that each West Entrance visit accounted for $152.67 in expenditures in the West

Yellowstone economy. Non-winter visitor expenditures were estimated at $25.37 per

visit. This result is consistent with the results of comparison data collected in a summer

1998 YNP visitor survey and data from the 1999 GYA visitor survey. While winter

visitation to YNP and resort tax collections are correlated, declines in park visitation in

the past have been offset by other recreational opportunities in the area. There are

several hundred miles of groomed trails in the parks, but also about 400 miles of trails in

nearby areas. Table 15 shows the annual change in West Entrance winter visits and the

annual change in resort tax collections for both the winter and year-round West

Yellowstone economy. Changes in park visitation are not closely correlated to changes

in winter tax collection. For example, when visits declined by 13.4% in 1995-96, winter

tax collections increased by 9.6%. The annual economy is not wholly driven by winter

visits. Correcting for inflation in the tax data would not change the substantive

conclusions.
CHAPTER III

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110

Table 15. West Entrance YNP winter visits and West Yellowstone resort tax

collections.

Year W. Entrance

Visits

Percent

Change†

Resort Tax –

Winter Months

Percent

Change

Resort Tax –

Year Round‡

Percent

Change*

92-93 70,844 - 305,615 -- 1,091,437 --

93-94 60,063 -8.2 304,638 -0.3 1,173,813 +7.5

94-95 66,294 +1.9 357,924 +17.5 1,450,882 +23.6

95-96 57,380 -13.4 392,158 +9.6 1,414,274 -2.5

96-97 56,069 -2.2 410,393 +4.6 1,498,577 +6.0

97-98 54,859 -2.1 436,219 +6.3 1,603,261 +7.0

98-99 59,928 +9.2 465,636 +6.7 1,714,878 +7.0

†

 From previous year

‡

 For December through March

*

 For 1993 through 1999

Between the last week of January and the first week of March 1999, winter visitors to

YNP and GTNP were surveyed regarding their winter trips to the GYA and winter

management of the parks in the GYA. During the winter sampling period, surveys were

distributed at the North, West, and East Entrances to YNP and at the Moran and Moose

Entrances to GTNP. The number of surveys distributed at each entrance was based on

the proportion of total winter visitation for each entrance during the 1997-98 winter

season. The NPS entrance station personnel were instructed to distribute the surveys

randomly to entering visitor groups. Respondents to the survey were asked what

activities they participated in during their visits to the parks. Overall, 73.6% of park

respondents reported snowmobiling, 10% reported riding a snowcoach, and 22.1%

reported cross-country skiing as one of the activities participated in during their visit to

the GYA. At some entrance stations, the percentage of visitors participating in different

activities varied greatly. For instance, 90.1% of respondents sampled at the West

Entrance to YNP reported snowmobiling during their trip. A substantial number of

survey respondents reported participating in a combination of activities, for example

snowmobiling and cross-country skiing, or riding a snowcoach and cross-country skiing.

This was one of several winter visitor surveys conducted in YNP, GTNP, or both since

1995. In addition, the states around the parks have conducted a number of winter visitor

surveys. There is substantial agreement between the surveys on the demographics of

winter visitors.

Minority and Low-Income Populations

Alternative winter management policies in YNP and GTNP have the potential to affect

differing socioeconomic groups in different ways. Table 16 gives an overview of how

the five GYA counties compare to the states of Montana, Wyoming, and Idaho in per

capita income, percent of population in poverty, and unemployment rate. The table also

shows statistics for the three-state American Indian population. American Indians were

included in the comparison because they are the predominant minority group in the
SOCIOECONOMICS

111

region. As of 1996 the 5-county region had a per capita income of $22,116, somewhat

higher than that of the 3-state area. The percent of the population in poverty across the

five-county area and the three-state region in 1995 was 11.7% and 13.7% respectively.

Unemployment in the five counties in 1996 was 3.8%, below the three-state average of

5.3%. Additionally, in communities such as Jackson, there may be considerable poverty

because the cost of housing is 176% of the state average, the overall cost of living is

132% of the state average, and the average earnings per job is below the state average.

Table 16 shows that the American Indian population in the 3-state region had a much

lower per capita income ($5,710) than either the 5-county GYA area or the 3-state region.

It also shows a much higher percentage of population living in poverty (43.3%), and an

unemployment rate (23.9%) much higher than the five counties or three states.

Table 16. Comparative statistics on economic status (1989).

Per Capita Income† Percent of Population

in Poverty†

Percent

Unemployment

Three-State Area

American Indians

$5,710 43.3% 23.9%

Five-County

GYA Area

$22,116 11.7% 3.8%

Three-State Region

(WY, ID, MT)

$19,988 13.7% 5.3%

†Per capita income and poverty status statistics and American Indian unemployment rate are from the U.S. Bureau of the

Census, 1990 U.S. Census Data. Percent unemployment is from the U.S. Bureau of the Census, USA Counties 1996 CDROM.

Park Visitors

The 1999 Winter Visitor Survey in the GYA found that 4.8% of winter visitors reported

having a 1998 total household income below $15,000. The proportion reporting a

household income below $40,000 was 22.1%. A 1999 summer visitor survey in YNP,

found 11.1% of respondents reported a household income below $15,000 and 28.8%

reported income below $40,000.

The reported median household income for winter visitors was between $60,000 and

$75,000 per year. For 1998 summer visitors, this median income fell between $40,000

and $65,000. The income level of winter visitors to the GYA varied greatly depending

on where the visitor lived. Overall, 25.1% of respondents living within the GYA

reported incomes below $25,000. For visitors living outside the GYA but within

Montana, Wyoming, or Idaho, this figure was 19.4%. Finally, for the group of winter

visitors who lived outside the 3-state area, only 5.2% reported household incomes below

$25,000. Based on the 1999 winter visitor survey, almost all the winter recreation

visitors in the GYA are white (99.0%). Most winter visitors are male (66%). This

compares to summer visitors that are 98% white and 50% male.
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112

Social Values

The public has strongly held and divergent values and opinions on public policy issues

concerning winter management of YNP and GTNP.

The winter visitor survey is just one of three NPS-sponsored surveys relating to the

socioeconomic impacts of winter management changes within the GYA parks (Duffield

et al. 2000). The other two surveys targeted summer visitors to YNP and the U.S.

population as a whole, as well as local and regional residents (Duffield et al. 2000). A

total of 1,137 completed surveys were obtained from winter GYA park visitors, and 257

from winter visitors to national forests in the GYA. The summer visitor survey collected

1,302 surveys from YNP visitors and the national phone survey resulted in 1,226

completed surveys. The phone survey sample was divided into three categories: GYA

residents; 3-state or regional residents (Idaho, Montana, and Wyoming); and the national

sample. Over 400 surveys were completed for each.

The three surveys asked several questions about visitor attitudes toward winter

management of YNP and GTNP. One question asked visitors about their preferred

policy for allowing winter access to Old Faithful. The results for the three surveys are

shown in Table 17, Table 18, and Table 19. Winter visitors generally preferred the

existing policy of grooming roads for snowmobile use. Many summer visitors preferred

to have a plowed road with a parallel groomed route for snowmobile use. There was also

support for the existing policy, as well as for allowing snowcoach, ski, and snowshoe

travel, but not snowmobiles. Among the public, the local population was evenly divided

between keeping the existing policy and allowing snowcoach, ski, and snowshoe access

only. However, the regional and national populations preferred the snowcoach option to

the existing policy. Among national respondents there also was substantial support for

allowing only skiing and snowshoeing.

Table 17. Preferred policy for allowing winter access to Old Faithful:

winter visitor sample.

Management Policy Park Sample (%)

Residents Nonresidents

Existing policy of grooming roads for

snowmobile use 45.3% 63.4%

Plow the road and groom a parallel route

for snowmobile use 12.8% 13.0%

Plow the road, but not groom a parallel

route for snowmobile use 6.2% 3.0%

Do not groom or plow, but allow ski or

snowshoe use only 10.4% 3.9%

Allow snowcoach, ski, and snowshoe

travel only, not snowmobiles 25.3% 16.8%

Sample size 414 700

Source: Duffield et al. (2000a)
SOCIOECONOMICS

113

Table 18. Preferred policy for allowing access to Old Faithful by residents and

nonresidents: summer visitor sample.

Management Policy Residents Nonresidents

Existing policy of grooming roads for snowmobile use 25.6% 23.3%

Plow the road and groom a parallel route for snowmobile use 31.0% 36.8%

Plow the road, but not groom a parallel route for snowmobile use 7.9% 7.7%

Do not groom or plow, but allow ski or snowshoe use only 6.9% 11.4%

Do allow snowcoach, ski, and snowshoe travel only, not snowmobiles 28.6% 20.8%

Sample size 203 832

Source: Duffield et al. (2000b)

Table 19. Respondent preference for alternative management options for winter

access to Old Faithful: random phone sample.

Management Policy Local Regional National

Existing policy of grooming the road for snowmobile

and snowcoach use 40.4% 32.8% 20.0%

Plow and open the roads in the winter for automobile

and bus access 5.6% 10.1% 11.6%

Do not groom or plow but allow only ski or

snowshoe access 9.6% 14.0% 25.0%

Allow ski or snowshoe access, but also groom for

snowcoaches 39.7% 37.3% 35.1%

Do not know 4.7% 5.8% 8.3%

Sample Size 413 408 405

Source: Duffield et al. (2000c)

Local = Resident of the 17-county GYA

Regional = Resident of the three-state area of Montana, Wyoming, and Idaho

National = U.S. resident

Survey respondents were also asked several general questions concerning winter use.

Respondents were asked whether they agreed or disagreed with the following statement:

“Visitors should have the opportunity for mechanized winter access into Yellowstone

National Park.” All respondents generally agreed with this statement (particularly winter

visitors) as summarized in Table 20. However, all respondents also agreed largely with

the statement “I am concerned about the possible disturbance of Yellowstone wildlife in

the winter.”
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114

Table 20. Level of agreement and disagreement with statements regarding winter

use management, by sample population.

Access: “Visitors should have the opportunity for mechanized winter access into YNP.”

Winter Resident Nonresident

% Agree 57.2% 73.1%

% Disagree 30.0% 15.6%

Summer

% Agree 51.4% 37.5%

% Disagree 33.7% 25.9%

Phone Local Regional National

 % Agree 63.7% 63.1% 49.0%

% Disagree 28.1% 27.5% 37.6%

Wildlife: “I am concerned about the possible disturbance of Yellowstone wildlife in the winter.”

Winter Resident Nonresident

% Agree 62.8% 60.3%

% Disagree 23.7% 21.0%

Summer

% Agree 67.2% 60.2%

% Disagree 15.4% 9.4%

Phone Local Regional National

 % Agree 62.4% 67.6% 77.4%

% Disagree 27.8% 24.4% 9.3%

Respondents were faced with the specific choice of trading access for the concern for

wildlife, as expressed in the following question: “Grooming the roads into YNP from

West Yellowstone and Mammoth for oversnow vehicles provides an easier winter route

out of the park for bison. If roads were not groomed, more bison might remain in the

park. Given this possibility, which of the following policies would you prefer?” The

choices were:

• “The current policy that allows for winter access.”

• “To close motorized winter access.”

• “Not sure.”

Summer nonresident visitors favored closing roads (1.4:1) as did regional (1.2:1) and

national residents (2.1:1). Summer resident visitors were evenly divided on the issue

while winter visitors favored having access (2.2:1) as did local phone respondents

(1.3:1). Tables 21, 21, 22, and 23 provide a detailed overview of responses to these

questions for winter and summer visitors and phone respondent populations.
SOCIOECONOMICS

115

Table 21. Visitors’ preference for bison management policies that could curtail

motorized winter access into YNP: Winter visitors.

Grooming the roads into YNP from West Yellowstone and Mammoth Hot Springs for oversnow

vehicles provides an easier winter route out of the park for bison. If roads were not groomed, more

bison might remain in the park.

Policy Choices Park Sample

Keep the current policy that allows

winter access 52.1%

Close motorized winter access 23.4%

Not sure which policy to prefer 24.6%

Sample size 1134

Table 22. Visitors’ preference for bison management policies that could curtail

motorized winter access into YNP by residents and nonresidents: Summer visitors.

Policy Choices Residents Nonresidents

Choose current policy that allows winter

access

37.4% 25.0%

Close motorized winter access 37.4% 34.6%

Not sure which policy to prefer 25.1% 40.3%

Sample size 211 1046

Table 23. Respondents’ preference for alternative winter access bison management:

Phone survey respondents.

Policy Choices Local Sample Regional

Sample

National

Sample

Keep existing policy of grooming for oversnow

vehicles 50.0% 41.3% 29.6%

Close motorized winter access to allow for bison

control 38.2% 48.2% 58.8%

Not sure 11.7% 10.5% 11.6%

Sample size 413 408 405
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116

Table 24. Social Values: Level of agreement and disagreement with statements

regarding.

Phone Summer Visitor Winter Visitor

Local Regional National Resident Nonresident Resident Nonresident

Access: “Visitors should have the opportunity for mechanized winter access into YNP.”

2:1

agree

2:1

agree

1.3:1

agree

1.5:1

agree

1.4:1

agree

2.4:1

agree

4.7:1

agree

Wildlife: “I am concerned about the possible disturbance of Yellowstone wildlife in the winter.”

2:1

agree

3:1

agree

9:1

agree

4.4:1

agree

6.4:1

agree

2.6:1

agree

3:1

agree

Close road for bison: Grooming the roads into YNP from W. Yellowstone and Mammoth for

oversnow vehicles provides an easier winter route out of the park for bison. If roads were not

groomed, more bison might remain in the park. Given this possibility, which of the following

policies would you prefer?

1.3:1

open

1.2:1

close

2.1:1

close

1:1

divided

1.4:1

close

2.2:1

open

Local = Resident of the 17-county GYA

Regional = Resident of the three-state area of Montana, Wyoming, and Idaho

National = U.S. resident

An interpretation of these responses is that, given all things equal, visitors would like

mechanized access into YNP in the winter. However, visitors are also concerned about

wildlife and possibly other resource impacts. When faced with a specific choice (help

bison versus mechanized access), it appears that there is a willingness on the part of the

public to accept major changes in access policy.

The national phone survey also collected information on participation in several winter

recreational activities. These data are summarized in Table 25, Table 26, and Table 27.

The basic finding is that the participation rates in snowmobiling and cross-country skiing

are higher at the local and regional level than in the nation as a whole. In addition, the

participation rates for both activities are quite similar, with skiing being slightly more

popular. The estimates for the region are in close agreement with the findings for

Montana (Sylvester and Nesary 1994).

Table 25. Reported respondent participation in winter activities.

Local Regional National

Snowmobiling 26.7% 16.9% 7.7%

Cross-country skiing 29.5% 17.1% 9.3%

Local = Resident of the 17-county GYA

Regional = Resident of the three-state area of Montana, Wyoming, and Idaho

National = U.S. resident
SOCIOECONOMICS

117

Table 26. Frequency of participation in activity: snowmobiling.

Local Regional National

Frequently 6.8% 4.6% 2.0%

Occasionally 10.7% 7.2% 2.9%

Rarely 8.9% 4.8% 2.8%

Never 73.6% 83.4% 92.3%

Sample size 413 408 405

Local = Resident of the 17-county GYA

Regional = Resident of the three-state area of Montana, Wyoming, and Idaho

National = U.S. resident

Table 27. Frequency of participation in activity: cross-country skiing.

Local Regional National

Frequently 8.9% 6.2% 2.2%

Occasionally 12.1% 5.4% 3.6%

Rarely 8.5% 5.5% 3.4%

Never 70.5% 82.9% 90.8%

Sample size 413 408 405

Local = Resident of the 17-county GYA

Regional = Resident of the three-state area of Montana, Wyoming, and Idaho

National = U.S. resident

An additional telephone survey was conducted for residents of Teton County, Wyoming

(Morey and Associates, Inc. 1998). Results were based on 300 interviews concerning

winter participation and attitudes. The study found that 21% of households snowmobiled

and 15% cross-country skied in YNP during the winter of 1997-98. In GTNP 12% of

residents snowmobiled, 46% cross-country or back-country skied, and 10% snowshoed.

A total of 52% of YNP users and 56% of non-users felt snowmobiles negatively impact

YNP in the winter. Of these 66% felt snowmobiles are too noisy, 44% felt they affect air

quality, 39% felt they disturb wildlife, and 25% felt there are too many. A total of 51%

of users and 61% of nonusers felt that there should be entry limits in YNP during the

winter. The survey also found that 7% of all respondents derived income from winter use

in YNP or GTNP.

Desire for Wildlife Viewing

Respondents to the winter GYA visitor survey were asked several questions regarding

wildlife in the GYA. When asked to list the three mammals or birds they would most

like to see in the GYA, respondents listed the wolf most frequently. About 36% of

respondents said that seeing or hearing wolves was one of their reasons for visiting the

GYA. Of this 36%, 10% said they would not have chosen to make the trip if wolves had

not been present in the GYA.

Bison were ranked fifth in the winter survey on the list of animals visitors would most

like to see in the GYA. Nearly 54% of respondents said that seeing bison was one of the
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118

reasons they made their trip to the GYA, and of this group, 12% said they would not have

made the trip if bison were not present in the GYA.

Nonmarket Values

Direct Recreation Use

The wildlife and natural environments of bison in the GYA are of value to park visitors,

hunters, and others who value the idea that these resources are maintained in a viable

state. Part of this value is reflected in the expenditures that visitors make for lodging,

food, and other travel services (see the previous sections Recreation Sector and Park

Visitors, Chapter III ). The main reason that visitors make the often long and expensive

trip to YNP is because the benefits of the trip exceed the dollar costs.

Benefit studies are concerned with the demand side of the tourism industry. Because

visitors are charged little or no fees for park visits or use of surrounding public lands for

hunting, snowmobiling, or other recreation, trip values do not have market prices. The

nonmarket value (values for items not exchanged in established markets) of trips for park

visitors is measured by how much they would be willing to pay over and above the costs

of the trip before they would choose to forego the trip entirely (Mitchell and Carson

1989). This area of research can be controversial, but most economists accept the

method for estimating the value of direct recreational use. The more controversial issues

are associated with estimating values where no direct on-site use is involved. The values

reported below are for direct use.

Analysis of responses to the 1999 GYA winter visitor survey show that the median trip

value for a winter trip to the GYA by residents of the 3-state region is $30. For those

GYA visitors who live outside the 3-state region, the median trip value is $145.

Nonmarket values can also be used to estimate the willingness of visitors to pay for

certain changes in their trips to the GYA. The 1999 winter visitor survey asked

respondents three questions intended to gauge visitor willingness to pay for certain

management changes within YNP.

Respondents to the winter survey who rented a snowmobile on their trip were asked if

they would be willing to pay a higher rental fee to rent a snowmobile that was as clean

and quiet running as a typical new car. The median willingness to pay to rent a clean,

quiet machine was an additional $46 above the current cost of renting the machine.

Winter visitors for whom YNP was a destination on their trip were asked if they would

pay an additional fee to cover the cost of plowing the road from West Yellowstone to Old

Faithful. The median willingness to pay for winter car and bus access to Old Faithful

was $6.

A final willingness to pay question was asked of winter visitors who reported skiing on

their trip to the GYA. This group was asked their willingness to pay to support improved

ski trail grooming and trailhead facilities within the park. The net willingness to pay for
SOCIOECONOMICS

119

an annual cross-country ski pass with improved ski trails and facilities within the park

was $46.

Non-Economic Costs/Values

Some people who commented on the Draft Environmental Impact Statement (DEIS)

stated that the economic analysis must include an assessment of the environmental costs

associated with snowmobiling. This environmental cost assessment would include the

cost of pollution and its impact on air quality, vegetation, ecology, or visitor experience.

Similar statements were made about calculating the economic cost of harassment or

disturbance to wildlife, and the removal of bison when they leave the park (due

presumably to the existence of groomed routes).

Such issues are partially answered by the assessment of nonmarket values, that is, the

willingness to pay for clean machines or viewing wildlife. Readers could view economic

impacts as the cost of reducing impacts on resources. However, for many people the issue

is instead related to the “intrinsic” value of the resource, not its value for being

experienced by people.

The response to such comments is twofold. First, the National Environmental Policy Act

(NEPA) does not require a “particularized assessment of nonenvironmental impact”, or

“particularized economic analysis” in looking at the effects on the quality of the human

environment. Second, NEPA does not require an assessment of impacts for which no

data can be acquired, or which is essentially speculative. The CEQ regulations do require

evaluation of ecological, aesthetic, historic, cultural, economic, social, and health

impacts. They do not require everything to be put into an economic context. It is

necessary to reveal possible impacts on wildlife, and unnecessary to put a dollar value on

them. The analysis needs to be sufficient for the decision to be made and no more. In

this instance, the decision to be made does not rest on economic criteria. That is, the

issues to be resolved lie largely in the areas of effects on natural resources and visitor

experience. Purely economic effects must be disclosed, and will be considered (see

Decision to be Made, Chapter I) as part of the decision making process.

Economic models are used in this EIS to evaluate the effects of various alternatives on

economic systems. This approach is used in many economic settings, not just in NEPA

analyses. The modeling of resource values (for example the value of an elk or of clean

water) is possible within identified limits and assumptions, and it is a valuable tool in

answering some questions. Often it is difficult to find much agreement on what the

assumptions should be, because they are literally value judgment. This is the source of a

primary limitation on such models: value lies in the eye of the beholder and there is no

agreement within the body politic on inherent value of resources in dollar.28

 

28 Comments were considered and are being addressed by the addition of this discussion into the FEIS. CEQ

regulations were reviewed. Reference Values of the Federal Public Lands (Kenney et al. 1998).
CHAPTER III

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120

Air Quality and Public Health

Over the past ten years, increases in the number of visitors using snowmobiles in YNP

and GTNP have intensified concerns regarding air pollution and its effects on the health

of park employees, visitors, and operators and riders of snowmobiles. A 2-stroke engine

that provides a high power/weight ratio powers the typical snowmobile, and these

engines produce relatively high emissions of carbon monoxide (CO) and unburned

hydrocarbons (HC) compared to modern automobile engines. They also do not

incorporate pollution control equipment. At present, there are no federal laws regulating

snowmobile engine exhaust emissions.

CO is a colorless, odorless, and poisonous gas produced by the incomplete burning of

carbon found in fuels. When CO enters the bloodstream, it reduces the delivery of

oxygen to the body’s organs and tissues. Health effects may include impairment of

visual perception, manual dexterity, learning ability, and performance of complex tasks;

headaches and fatigue; or respiratory failure and death.

In addition to CO emissions, snowmobiles generate particulate matter (PM) and volatile

organic compounds (VOCs). VOCs include air toxics or hazardous air pollutants such as

benzene and formaldehyde. PM includes dust, dirt, soot, smoke, and liquid droplets

directly emitted into the air by sources such as power plants, vehicles, construction

activity, fires, and natural windblown dust. Vehicle exhaust PM emissions may also

contain hazardous air pollutants such as 1,3-butadiene. Health effects from PM

emissions may include reduced lung function, aggravation of respiratory ailments, longterm risk of increased cancer rates, and development of respiratory problems.

Snowmobile emissions have been the source of the vehicle emission and health related

complaints in YNP. For example in 1993 and 1994 YNP received over 1,200 complaint

letters concerning employee and visitor health and excessive snowmobile pollution

(Sacklin, pers. com., 1998).

Regulatory Overview Including Visibility

YNP and GTNP are classified as mandatory Class I areas under the Federal Clean Air

Act (42 USC 7401 et seq.). This air quality classification is aimed at protecting parks

and wilderness areas from air quality degradation. The act gives federal land managers

(FLM) the responsibility for protecting air quality and related values (AQRVs).

According to a publication entitled Federal Land Managers’ Air Quality Related Values

(FLAG) Report, (NPS, U.S. Forest Service (USFS), and U.S. Fish and Wildlife Service)

AQRV’s are the following: “A resource, as identified by the FLM for one or more federal

areas that may be adversely affected by a change in air quality.” The resource may

include visibility or a specific scenic, cultural, physical, biological, ecological, or

recreational resource identified by the FLM for a particular area. The Clean Air Act

defines mandatory Class I areas as national parks over 6,000 acres, wilderness areas over

5,000 acres, and national memorial parks over 5,000 acres designated as of the date of the

act. The Parkway is a Class II area and is managed as a Class I area under NPS policy.
AIR QUALITY AND PUBLIC HEALTH

121

National Ambient Air Quality Standards

The Federal Clean Air Act, as amended in 1990, requires the EPA to establish national

ambient air quality standards (NAAQS) to protect public health and welfare. Standards

have been set for six pollutants: particulate matter less than 10 microns (PM10), carbon

monoxide (CO), nitrogen oxides (NOX), sulfur dioxide (SO2), ozone (O3), and lead (Pb).

These pollutants are called criteria pollutants because the standards satisfy criteria

specified in the act. Nonattainment areas are subject to planning and pollution control

requirements that are more stringent than areas that meet standards.29 The areas covered

by the three park units are in attainment.

Table 28 lists the NAAQSs and ambient air standards adopted by Wyoming, Montana,

and Idaho. The States of Montana and Wyoming have adopted more stringent standards

for some pollutants.

Air Quality Monitoring

The Montana Department of Environmental Quality (DEQ) Monitoring and Data

Management Bureau installed a microscale CO monitoring station on the northeast side

of the West Entrance of YNP in October 1998. A particulate sampling station operated

by the Montana DEQ is located outside YNP in the town of West Yellowstone. As

reported in the aerometric information retrieval system (AIRS), the second highest CO 8-

hour average in 1999 was 5.0 ppm, and the corresponding average in 1998 was 3.6 ppm

(www.epa.gov/airsdata/). These compare to the federal and Montana CO 8-hour ambient

air quality standards of 9.0 ppm. At the West Yellowstone monitor, the highest 24-hour

PM10 measurement in 1999 was 61 μg/m3, and the corresponding measurement in 1998

was 40 μg/m3 (www.epa.gov/airsdata/ ). These compare to the 24-hour 150 μg/m3

federal and Montana PM10 ambient air quality standards.

 

29 A nonattainment area is a geographic area identified by the U.S. EPA and/or a state as not meeting either

the NAAQS or state ambient air quality standards for a given pollutant.
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122

Table 28. Primary ambient air quality standards.

Pollutant Time

Period Federal Wyoming Montana Idaho Purpose

1-hour 35 ppm 35 ppm 23 ppm 35 ppm Carbon

Monoxide

(CO) 8-hour 9 ppm 9 ppm 9 ppm 9 ppm

To prevent high

levels of carboxyhemoglobin

24-hour

Average

150 μg/m3

(arithmetic)

150 μg/m3

(arithmetic)

150 μg/m3

(arithmetic)

150 μg/m3

Respirable (arithmetic)

PM10

(current) Annual

Mean

50 μg/m3

(arithmetic)

50 μg/m3

(arithmetic)

50 μg/m3

(arithmetic)

50 μg/m3

(arithmetic)

24-hour

Average

65 μg/m3

(arithmetic)

65 μg/m3

(arithmetic)

-- --

Fine PM2.5

(proposed) Annual

Mean

15 μg/m3

(arithmetic)

15 μg/m3

(arithmetic)

-- --

To prevent chronic

diseases of the

respiratory tract

and improve

visibility

1-hour -- -- 0.30 ppm --

Nitrogen

Dioxide

(NO2) Annual

Average

0.053 ppm 0.05 ppm 0.05 ppm 0.05 ppm

To prevent

breathing

difficulties, reduce

smog and acid rain

formation, and

improve visibility

3-hour

0.5 ppm

(secondary)

0.5 ppm

0.5 ppm

(1-hour)

0.5 ppm

(secondary)

24-hour 0.14 ppm 0.1 ppm 0.1 ppm 0.14 ppm

Sulfur

Dioxide

(SO2)

Annual

Average 0.03 ppm 0.02 ppm 0.02 ppm 0.03 ppm

To prevent

increased

respiratory

damage, acid rain,

and crop damage

and to improve

visibility

Ozone

(current) 1-hour 0.12 ppm -- 0.10 ppm 0.12 ppm

Ozone

(proposed) 8-hour 0.08 ppm 0.08 ppm -- --

To prevent

breathing

difficulties, eye

irritation, and

biological effects

to sensitive species

90-day

Average 1.5 μg/m3

1.5 μg/m31.5 μg/m31.5 μg/m3

Lead (Pb)

Calendar

Quarter 1.5 μg/m3

1.5 μg/m31.5 μg/m3

To prevent

impaired

production of

hemoglobin
AIR QUALITY AND PUBLIC HEALTH

123

In 1980 YNP was added to the National Atmospheric Deposition Program (NADP)

network, which monitors wet acid deposition at Tower Falls, located in the north central

area of the park. YNP also participates with the EPA in operating a site as part of the

Clean Air Status and Trends Network or CASTNet, formerly known as the National Dry

Deposition Network. CASTNet provides atmospheric data on the dry component of total

acid deposition and therefore complements the NADP network. Ground-level ozone also

is monitored as part of the CASTNet. YNP also participates in a collaborative visibility

monitoring program known as the Interagency Monitoring of Protected Visual

Environments or IMPROVE program. The IMPROVE and CASTNet sampling

equipment, located at Yellowstone Lake, measures atmospheric concentrations of

aerosols, sulfates, nitrates, ammonium, sulfur dioxide, and nitric acid and includes an

ozone analyzer, as well as meteorological equipment.

Air pollutants, primarily from nitrogen and sulfur, may be deposited on terrestrial and

aquatic resources through rain, snow, cloudwater, dryfall, and gases, and may affect

resources such as vegetation and water chemistry. To estimate deposition of air

pollutants, data is collected at wet (rain and snowpack) and dry deposition-monitoring

stations in or near the GYA parks. Snowpack samples from groomed road snowpacks

had higher levels of ammonia (NH3+) and sulfate (SO42-) than those taken from

roadways, indicating direct source deposition from snowmachines. Levels of NO3- were

similar in both on- and off-road sites indicating that they can be attributed to regional

sources.

Precipitation volume and chemistry have been monitored at the NADP Tower Falls site

since 1980. Annual precipitation amounts are low (30 to 45 centimeters [cm] per year),

and the acid-forming precursors (such as nitrate and ammonium) in rain and snow result

in very low levels of sulfur and nitrogen. Similarly, the contributions of dry depositions

of sulfur and nitrogen are low relative to wet deposition because there are no significant

emission sources near either YNP or GTNP (Peterson 1998).

There is no wet or dry deposition monitoring station in GTNP for sulfur and nitrogen.

However, GTNP is exposed to the same general air masses as YNP, which has both wet

or dry deposition monitoring stations, and both parks experience prevailing winds from

the southwest. There are no large point sources of nitrogen or sulfur adjacent to either

park that might cause major differences in local deposition.

Air Quality Conditions

Since there is little industrial activity and a relatively low population in northwestern

Wyoming, overall regional air quality in the parks is good. All park areas are located in

areas that are in attainment with all federal and state ambient air quality standards noted

in Table 28. The major sources of air pollutants in the area are those emitted by motor

vehicles (automobiles, buses, snowcoaches, and snowmobiles) concentrated along

motorized routes, and smoke from wood fires, including stoves, fireplaces, and
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124

campfires. The predominant fuels consumed by stationary sources in the parks are

propane and number two heating oil.

Most of the industrial activity in Wyoming occurs in the eastern counties near the cities

of Gillette and Casper and in the southwestern counties around Rock Springs. Point

sources of sulfur dioxide (SO2), and nitrogen oxides (NOX) are located within 150

kilometers (km) of YNP with most of the pollution coming from oil and gas processing,

electric utility power plants, and industrial fossil-fuel combustion by industrial sources

(Peterson 1998).

Air Quality and Personal Exposure Studies

A number of studies have been undertaken in recent years to characterize air quality and

personal exposure to air pollutants in YNP and GTNP. These studies focused primarily

on CO and particulate matter (PM) emissions and their impact on air quality and personal

exposure. The studies used varying sampling methods, time periods, and other

parameters that preclude a direct comparison to each other. With the exception of the

Montana DEQ monitoring data that are reported as part of the EPA AIRS, study data are

not directly comparable to the national and state ambient air quality standards that were

discussed earlier. Table 29, Table 30, and Table 31summarize the findings of these

studies of CO, PM, and volatile organic compound (VOC) emissions.

Table 29. Carbon monoxide emissions study results.

Time

Period Study Description Study Results Reference

1999 • 5.0 ppm second highest 8-hour

average

1998

Carbon monoxide monitoring West

Entrance to YNP • 3.6 ppm second highest 8-hour

average

EPA AIRS Quick

Look Report

Winter

1996

Carbon monoxide monitoring at YNP

West Entrance, Old Faithful corridor,

and Flagg Ranch

• 23.9 - 31.0 ppm West Entrance

• 12.4 - 36.2 ppm road corridor

• 0.1 - 110 ppm Flagg Ranch

NPS 1996b

Winter

1995

Carbon monoxide monitoring (grab

sampling) near West Entrance

• 55 ppm maximum 1-hour level NPS 1996a

Winter

1996

Carbon monoxide exposure while

trailing a single snowmobile in GTNP

• 0.51 - 23.1 ppm average exposure

at 25 - 125 feet at speeds of 10-40

mph

Snook and Davis

1997
AIR QUALITY AND PUBLIC HEALTH

125

Table 30. Particulate matter emissions study results.

Time

Period Study Description Study Results Reference

1999 • 61 μg/m3

 highest 24-hour average

• 15 μg/m3 annual arithmetic mean

1998

PM10 monitoring station in West

Yellowstone • 40 μg/m3

 highest 24-hour average

• 16 μg/m3 annual arithmetic mean

EPA AIRS Quick

Look Report

Winter

1995

Particulate high-volume sampling at

West Entrance and in the town of West

Yellowstone

• 7 – 40 μg/m3 24 hour average

range in the town of West

Yellowstone

NPS 1996a

PM2.5 fixed site 8-hour monitoring at

three YNP locations

• 38.6 – 78.0 μg/m3 (62.1 μm3

average) at West Entrance

• 24 – 29.3 μg/m3 (26.5 μm3 average)

at Madison

• 16.7 – 39.5 μg/m3 (24.7 μm3

average) at Old Faithful

PM10 fixed site 8-hour monitoring at two

West Yellowstone and two YNP sites

• 1.5 μg/m3 at residential area north

of downtown West Yellowstone

• 13.5 μg/m3 at downtown West

Yellowstone

• 37 μg/m3 at West Entrance to YNP

• 25.5 μg/m3 at Old Faithful

Winter

1999

Personal exposure monitoring for PM4

of NPS patrol rangers and employees at

West Entrance for 8-hour work shift

• A snowmobile mechanic had

highest exposure

• An office worker had lowest

exposure

• Employees working the express

lane had about double the exposure

than those working the regular

lanes

Kado et al. 1999

Table 31. Volatile organic compound emissions study results.

Study

Time

Period

Study Description Study Results Reference

Winter

1999

Personal exposure of NPS employees to

volatile organic compounds, including

benzene, toluene, and aldehydes

(oxidation products of automotive

engine combustion)

• Toluene had highest concentration

• West Entrance employees had highest

VOC exposure, followed by

snowmobile patrol rangers, followed

by a snowmobile mechanic

• Short-term peak exposures to benzene

and toluene were considerably higher

than integrated badge samples

• Formaldehyde and acetaldehyde

exposures were higher in the A.M.

than the P.M. at the West Entrance

Kado et al. 1999
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126

Public Safety

Much of the trail system in the GYA accesses remote areas. Skiers, as well as

snowmobile operators and riders, may be subject to risks from cold, rapidly deteriorating

weather, or other inherent backcountry dangers including terrestrial features and deep

off-trail snow. Ease or difficulty of search and rescue efforts and transporting victims to

medical facilities are also concerns. Backcountry accident victims also risk further injury

during transport to the trailhead. Poor road and weather conditions, operator error, and

the possibility of mechanical failure can combine to create safety concerns unique to

snowmobilers. In areas of mixed uses, such as parking areas for both ski and

snowmobile visitors, there are additional dangers. The risk of accidents also may be

affected by signage and traffic control.

The increase in motorized and nonmotorized winter use over the past 10 years has been

accompanied by an increase in reported accidents. Federal land managers believe that

some motorized and nonmotorized accidents are not reported, and there may be more

accurate records on motorized accidents because of the level of property damage and

injury. Accidents are defined as incidents involving property damage or injuries that are

reported to the agencies.

Generally, the number of snowmobile accidents in YNP has increased as snowmobile

visitation has increased. Although snowmobile fatalities are relatively rare, they do

occur. In the last 10 years, eight fatalities from snowmobile accidents have occurred: one

in 1989, four in 1994, one in 1997, and two in 1999. In calendar year 1994, snowmobile

deaths accounted for 44% of all park fatalities. Numbers may be higher, as statistics are

kept only on fatalities that occur within park boundaries; they do not include victims

whose injuries prove fatal following transport to an external medical facility.

In 1992-93, YNP converted the Old Faithful ambulance to an oversnow ambulance, and a

4-wheel drive Suburban was converted to an oversnow vehicle in the Canyon area. This

vehicle is used to transport persons in emergencies on the east side of the park.

Ambulance speed depends on the quality of the groomed road surface, varying from 7

mph to 25 mph. Weather permitting, helicopter evacuation services are available for lifethreatening emergencies through the Eastern Idaho Regional Medical Center.

Park visitors are provided safety information as part of the information they receive upon

entering the park. In addition the International Snowmobile Manufacturers Association’s

“Safe Rider Program” has been instrumental in distributing information to snowmobilers.

For example in 1995 the Idaho State Snowmobile Association (ISSA) and the Idaho

Department of Parks and Recreation implemented a snowmobile safety-training program.

Both the ISSA and affiliated chapters have trained hundreds of snowmobilers in safe

snowmobiling practices through this program.
127

Case Incident Reports—YNP

Rangers complete Case Incident Reports (CIRs) when they have been summoned to a

specific location. The content of the CIRs during the winter season vary widely; for

example, they can report visitor assists for gasoline sales and snowmobile repairs, searchand-rescue assistance to other area agencies, or the presentation of a talk to a group of

people. YNP compiled a draft report on CIRs involving winter recreationists in YNP and

outside the park for which park rangers’ assistance was requested for the period

December 1995 to March 2000 (Wondrak 1998, rev. 1999 and 2000). The report

covered CIRs that related to winter recreationists participating in snowmobiling,

snowcoach riding, and skiing. Other winter recreational activities such as snowboarding,

sledding, ice skating, and snowshoeing are conducted in YNP during the winter, but there

were no CIRs associated with these activities in the seasons covered by the report.

During the five winter seasons (1995-2000), about 319 (92%) of the CIRs involved

snowmobiles (snowmobiles account for 61% of overall winter use). Fifteen CIRs

involved skiers and fourteen involved snowcoach riders. The following table contains an

accounting of the incidents by activity type. (Note: “Agency” assists are incidents in

which NPS employees are contacted by the public safety departments from surrounding

jurisdictions outside the park to provide assistance with situations such as search and

rescue or incidents involving wildlife associated with the park. “Visitor assists” are

events where a park visitor was provided assistance such as fuel, equipment repairs,

minor first aid, or directions.) See Table 32 for case incident report details.

Table 32. Case incident reports from December-March 1995-2000.

Skiing Use

Incident

Description Agency Assist Avalanche Death Search &Rescue Visitor Assist

Total Frequency 1 2 8 4

Snowcoaches

Incident

Description Entering Closed Area Visitor Vehicle Assistance

Total Frequency 1 13

Snowmobile Use

Incident

Description

AbandonedAgencyAssistSuspendedLicenseDeathDUIEnteringClosed AreaExcessiveNoiseOff-roadTravelSearch &RescueSuspectedIntrusionSpeedingUnlicensedDriverUnsafeOperationVisitorAssistMisc.

Total

Frequency 3 46 3 1 8 19 3 11 4 9 8 12 7 172 13

[Note: Miscellaneous reports comprised the remaining thirteen snowmobile CIR's.]
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Emergency Medical Services Reports—YNP

Winter EMS reports for YNP have been compiled for five seasons (1995-2000) and are

shown in Table 33 (Wondrak 1998, rev. 1999 and 2000). Information is limited to the

number of people who rangers reported assisting, and the types of activities that resulted

in the incidents.

Table 33. EMS reports by activity type from December-March 1995-2000—YNP.

Activity Type Number of People Assisted Percentage of total

Ice skating 2 1%

Sledding (nonmotorized) 1 1%

Skiing 30 16%

Snowboarding 1 1%

Snowcoach riding 18 9%

Snowmobiling 120 63%

Snowshoeing 2 1%

Walking on boardwalks, etc. 15 8%

Source: NPS

Motor Vehicle Accidents—YNP

Winter motor vehicle accidents (MVAs) have also been compiled for YNP (Wondrak

1998, rev. 1999 and 2000). The report excludes accidents that occurred on US Highway

191. Accidents that occurred on the Grand Loop Road and on the road between Gardiner

and Cooke City, Montana are included.

Vehicles

Not including the accidents that occurred on US Highway 191, there were 298 motor

vehicle accidents from December through March 1995-2000. Of those 298 accidents,

201 (67%) involved snowmobiles, 82 (28%) involved private passenger vehicles, and 15

(5%) involved service vehicles such as busses, delivery vans, garbage trucks, snowplows,

and snowcoaches. These numbers may be higher, as some accidents may go unreported.

In FY 1998, snowmobilers comprised just 2% of the year’s total visitors, but were

involved in 9% of the year’s MVAs.

Accident Descriptions

The most frequent types of motor vehicle accidents involving wheeled-vehicles in YNP

(excluding US Highway 191) were:

• Vehicle versus vehicle—35%;

• Vehicle versus animal (bison, elk, deer, sheep, or wolf)—32%;

• Single car accidents—18%; and,

• Vehicle versus inanimate object—15%.
129

The most frequent types of snowmobile accidents were:

• Snowmobile versus landscape feature (tree, river, rock, or ditch)—34%;

• Snowmobile versus snowmobile—33%;

• Lost control of snowmobile, rollovers, and swerves—17%;

• Snowmobile versus snowcoach—5%; and,

• Snowmobile versus bison—4% (most snowmobile versus bison accidents occurred after

dark).

Owner

About 70% of all visitors use rented snowmobiles, and 76% of the snowmobiles involved

in accidents from 1995-2000 were rental snowmobiles (Borrie 1999; Wondrak 1998, rev.

1999 and 2000). The U.S. Government owned 6% of the snowmobiles involved in

reported accidents, 15% were privately owned, and 2% were owned by YNP’s

concessioners (for employee use). This indicates that about 8% of people involved in

wintertime MVAs in YNP are employees of the park or its concessioners. Similarly,

about 9% of people involved in reported snowmobile accidents between 1995-2000 listed

YNP as their home.

Contributing Factors

When completing MVA reports, rangers often explain why accidents occurred. When an

explanation was provided, the following were cited as contributing factors to snowmobile

accidents from 1995-2000:

• Just lost control, 27%. (These often resulted from a rider mistaking the throttle for the

brake, and consequently accelerating inadvertently while attempting to slow.)

• Poor driving skills, 23%. (For example, improper passing, driving left of center, driving

the wrong way down a one-way road.)

• Inattention, 15%.

• Poor road conditions, 12%.

• Inexperience with snowmobiles, 7%.

• Bison in road, 6%.

• Defective machine, 4%.

• Swerving to avoid collision, 3%.

• Other, 2%.

• Alcohol, 1%.

Location

Over the five winters covered in the report, most snowmobile accidents (51%) occurred

on the part of the Grand Loop from the West Entrance to the Old Faithful area. The

section of the Grand Loop from Old Faithful to the South Entrance accounted for the next

largest percentage of snowmobile accidents with 23%. About 57% of the motor vehicle

accidents involving wheeled-vehicles occurred on the road between Gardiner and

Mammoth Hot Springs.
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Time

About 90% of motor vehicle accidents involving snowmobiles occurred during daylight

hours (8 A.M. to 5 P.M.). The remaining 10% occurred during the night and into the

morning from 5 P.M. to 8 A.M. Travel during the night can be particularly dangerous

when animals on the roadway are difficult to see. Most snowmobile versus bison

accidents, which often result in serious injury, occurred during the night and comprise

35% of all nighttime snowmobile accidents.

Injuries

From 1995 to 2000:

• 73% of MVAs involving snowmobiles resulted in no reported injuries;

• 13% resulted in serious injuries;

• 13% resulted in minor injuries; and,

• 1% resulted in death.

Age

About 4% of snowmobile accidents from 1995 to 2000, where driver age was recorded,

were caused by drivers between 10 and 15 years of age. This number is substantially

lower than for the years prior to winter 1993-94 before the park began to require that

snowmobilers be licensed drivers. Overall, 48% of snowmobile accidents were caused

by drivers 35 and younger.

Citations—YNP

By far, the most common winter traffic violation in YNP is speeding on US 191. US 191

is a commercial route with a speed limit of 55 mph and is a major traffic corridor linking

the cities of Bozeman, Big Sky, and West Yellowstone to Ashton and Idaho Falls. The

highway is intended for and receives a substantially different sort of use than the Grand

Loop road or even the Gardiner to Cooke City road. Information about citations issued

on 191 is not included here for this reason. Data was also collected on winter season

traffic citations that were issued to vehicle drivers during the past five winters. The

results are discussed below by category.

Vehicles

Excluding those that occurred on US Highway 191, YNP’s rangers issued 1,296 traffic

citations during December through March of 1995 to 2000. Of those:

• 89% were issued to drivers of snowmobiles;

• 10% were issued to drivers of wheeled-vehicles, including pick-up trucks, cars, SUVs, vans

and mini-vans; and

• 1% were issued to drivers of bicycles, snowcoaches, or unspecified vehicles.

Snowmobilers comprised 61% of YNP’s winter visitation during these years,

outnumbering auto passengers by slightly more than 2 to 1.

Incident Descriptions

Of the 1156 citations issued to snowmobilers:
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• 34% were issued for speeding;

• 20% were issued for off-road travel;

• 20% were issued for driving without a license or allowing another to do so;

• 10% were issued for failure to maintain control and/or unsafe operation;

• 10% were issued for traffic violations; and,

• 5% were issued for entering closed areas.

All other violations comprised 1% of overall snowmobile citations.

Case Incident Reports—GTNP and the Parkway

Analysis of case incident reports (CIRs) in GTNP and the Parkway includes those reports

related to winter recreationists engaged in wheeled-vehicle operation, riding

snowmobiles, participating in skiing and snowboarding, and as passengers in

snowcoaches and snowplanes. CIRs involving wheeled-vehicles on US Highways

191/26/89 south of Moran Junction in GTNP were excluded, as that route is a major

transportation artery with substantial use unrelated to recreation within the park areas.

The summary of CIRs encompasses five winter seasons for the months of December

through March 1995-2000 (Table 34).
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Table 34. Case incident reports from December-March 1995-2000.

Skiing Use

Incident

Description

Agency Assist Entering

Closed Area

Injury Pet in Closed

Area

Search and Rescue

Total

Frequency 1 1 1 3 8

Snowboard Use

Incident Description Agency Assist Entering Closed Area

Total Frequency 1 1

Snowcoach Use

Incident Description Visitor Assist

Total Frequency 1

Snowmobile Use

Incident

Description

Agency

Assist

Damage to

Property

Entering

Closed Area/

Off-Road

Misc. Traffic

Violations

Parking

Search and

Rescue

Speeding

Suspected

Intrusion

Underage

Operation

Visitor Assist

Total

Frequency

27 4 57 13 3 2 3 6 2 5

Snowplane Use

Incident Description Entering Closed Area Property Damage

Total Frequency 1 1

Wheeled Vehicle Use

Incident

Description

Agency Assist

Entering Closed

Area/Off-Road

Fail to Obey

Traffic Device

Investigation

Misc. Traffic

Violations

No Driver's

LicenseParking

Pet in Closed

Area

Speeding

Unsafe Operation

Vehicle

Equipment

Visitor Assist

Weapons

Violation

Total

Frequency 9 9 16 4 31 12 30 8 316 17 27 75 9

Source: Grand Teton CIR reports

Emergency Medical Service Reports—GTNP and the Parkway

Emergency medical service (EMS) reports were compiled for five winter seasons from

December through March 1995-2000 in GTNP and the Parkway. Frequently, the EMS

reports do not list the type of activity victims were engaged in at the time of the incident.

The activities and data in the following table reflect incidents involving winter

recreationists and are limited to incidents that were reported to rangers and required EMS

assistance. The analysis excludes EMS activities related to wheeled-vehicle traffic on

US Highways 191/26/89.
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Table 35. EMS reports by activity type from December-March 1995-2000.

Activity Type Number of Persons Assisted Percentage of Total

Not reported 12 66%

Snowmobile 5 28%

Snowcoach 1 6%

Source: Grand Teton EMS reports

Motor Vehicle Accidents—GTNP and the Parkway

Winter motor vehicle accidents (MVAs) were analyzed for five years from December

through March 1995-2000. MVAs involving wheeled-vehicles on US Highways

191/26/89 south of Moran Junction in GTNP were excluded from the analysis.

Vehicles

Not including the accidents that occurred on US Highways 191/26/89 south of Moran

Junction in GTNP, there were 74 MVAs from December through March 1995-2000. Of

those 74 MVAs, 66 (89%) involved wheeled-vehicles and 8 (11%) involved

snowmobiles. The accident statistics for GTNP and the Parkway show a greater

percentage of the MVAs involving wheeled-vehicles than is the case for YNP.

Accident Descriptions

The types of MVAs for wheeled-vehicles in GTNP and the Parkway were:

• Vehicle versus vehicle—40%;

• Single vehicle accidents—38%;

• Vehicle versus animal (bison, elk, or moose)—18%; and,

• Vehicle versus snowmobile—4%.

The types of snowmobile accidents were:

• Lost control of snowmobile—29%;

• Snowmobile versus landscape feature (tree or lake)—29%;

• Snowmobile versus wheeled-vehicle—29%; and,

• Snowmobile versus snowmobile—14%.

Location

Wheeled vehicle accidents occurred most frequently from Colter Bay to Moran Junction

(38%) and from Flagg Ranch to Colter Bay (24%). Most snowmobile accidents (88%)

occurred between the South Entrance of YNP and Flagg Ranch.

Injuries

Most snowmobile MVAs in GTNP and the Parkway resulted in no injuries (88%).

Visitors have expressed concern to park staff about safety on the Continental Divide

Snowmobile Trail (CDST) in GTNP because of shared snowmobile and automobile use

in US Highways 191/26/89. Although no fatalities have occurred on the CDST within

GTNP or the Parkway, several injuries and one fatality occurred on the CDST/US

Highway 287 (near Togwotee Pass) because of automobile-snowmobile collisions.
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Vehicle versus snowmobile accidents occurred mainly in the Flagg Ranch area. Causes

for these accidents included traveling too fast for conditions, unsafe vehicle operation,

and an accident occurred when a vehicle with a trailer attempted to swerve around a

snowmobile.

Citations—GTNP and the Parkway

Statistics for citations issued to winter recreationists engaged in wheeled-vehicle touring

and snowmobiling in GTNP and the Parkway were compiled for five winter seasons from

December through March 1995-2000. There were no citations issued for recreationists

involved in snowcoach touring.

Vehicles

Excluding those that occurred on US Highways 191/26/89, there were 257 citations

issued in GTNP and the Parkway. Of those 257 citations, 190 (74%) involved wheeledvehicles and 67 (26%) involved snowmobiles.

Incident Descriptions

Of the 67 citations issued to snowmobilers:

• 81% were issued for off-road travel or entering closed areas;

• 6% were issued for unsafe operation;

• 2% were issued for speeding;

• 2% were issued for allowing a driver to operate a snowmobile without a license;

• 5% were issued for traffic violations; and

• 6% were issued for unspecified offences.

Note: The total exceeds 100% due to rounding.

Avalanche Hazards

Yellowstone National Park

In YNP, there are risks associated with both avalanches and avalanche control.

Avalanches occur in many locations throughout the park where slopes are greater than

30°. Three avalanche fatalities have occurred in YNP over the past decade: one in 1992

and two in 1997. All were backcountry skiers. One was an NPS employee and two were

park volunteers. Depending on snow conditions and weather, most areas available for

and used by backcountry skiers are subject to avalanches.

Avalanches are prevalent or a concern in three locations adjacent to roads, especially

because ground and weather conditions are highly changeable. Winter avalanche control

is currently practiced at Sylvan Pass and the Talus Slope (south of Lewis Lake). Sylvan

Pass and the Talus Slope area include road segments that are groomed in the winter for

snowmobile use. Washburn Hot Springs Overlook, on the Dunraven Pass road, receives

avalanche control during spring plowing. This area contains designated ungroomed

nonmotorized trails.

The NPS has conducted an avalanche control program for these three avalanche areas

since the 1970s. The objective of avalanche control is to maintain the road in a
135

reasonably safe condition for visitor traffic and for spring plowing. In YNP rangers

achieve this objective by either firing artillery shells or lobbing charges into the snowcovered slopes of the three areas mentioned above while the roads in question are

temporarily closed to visitor traffic. Control operations at the Talus Slope and Washburn

Hot Springs Overlook are relatively minor and infrequent compared to those conducted

on Sylvan Pass. Sylvan Pass is the 1-mile long portion of the East Entrance Road that

crosses the crest of the Absaroka Mountains. The pass is located between Top Notch

Peak on the south and Hoyt and Avalanche Peaks on the north, and is situated at an

elevation of 8,162 feet. It receives a great deal of snow and is extremely windy. Long,

unbroken talus slopes descend from the surrounding peaks to the pass at angles of nearly

45°. Frequent severe weather often necessitates closing the road to all visitation,

sometimes for extended periods until storm cycles clear and control work can begin.

Experience has shown that it is unsafe and unproductive to try to open the road during a

winter storm.

Risks associated with avalanche control can potentially affect both employees and

visitors. To access the gun platform on Sylvan Pass, from which control is practiced,

employee crews are often forced to snowmobile directly beneath the snow walls that they

intend to release. In addition, the artillery and explosives used to initiate avalanches have

occasionally failed to detonate upon force of impact. In these instances the proximate

location of unexploded shells generally must be noted, and the shells searched for during

the following summer. Unexploded shells generally land in remote areas that receive

little visitation due to the lack of trails and unusually rugged nature of the terrain. A

potential risk to visitors and wildlife does exist. It has been estimated that there may

currently be as many as 30 unexploded shells in these areas of YNP’s backcountry.

When Sylvan Pass is not used during the winter, some form of avalanche control would

be necessary during spring plowing.

At the Talus Slope, an avalauncher is used to lob charges onto the slope. Installed in

1999, the avalauncher allows for remote delivery of explosives, minimizing the need for

hand-set charges.

Grand Teton National Park and the Parkway

Due to the combination of steep, mountainous terrain and heavy snowfall, considerable

avalanche potential exists in many locations throughout GTNP. While avalanches can

occur on almost any gradient of slope, the potential for dangerous avalanche conditions is

highest on slopes in the 30° to 45° range (NPS 1998). Backcountry skiers and climbers

sometimes initiate avalanches in GTNP.

Although GTNP does not conduct any avalanche control activities (except to reduce

danger in a rescue situation), the historical number of avalanche accidents in the park is

low. This may be partially due to the fact that there are no locations of high avalanche

potential adjacent to roads. In the past decade, there has been one avalanche-related
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fatality. This fatality occurred when an individual attempted a climb of the south side of

Mount Wister in a remote area of Avalanche Canyon.

Jackson Hole Mountain Resort borders the southern boundary of GTNP, which creates an

opportunity for skiers to easily enter the park through steep avalanche terrain. For this

reason, the park boundary has been controlled. The Jackson Hole Ski Patrol monitors

avalanche conditions, and backcountry skiers are required to enter the park through

designated gateways that have a lower avalanche hazard potential. Fewer controls may

be present in future years.

The USFS produces a daily update of avalanche conditions in the Teton and Gallatin

Ranges. YNP and GTNP provide staff and visitors with this report to assure awareness

of dangerous avalanche conditions in the area. However, the parks also advise that

winter backcountry users should be aware of the possibility of avalanche hazards at all

times.

Geothermal Features

YNP is known worldwide for its geysers, hot springs, travertine terraces, mud pots, and

fumaroles. These are important resources that can be harmed by humans. Harm to

geothermal resources also harms plants and animals that are dependent on them.

Water Resources

Water Quality

The GYA encompasses a 3,500 square mile watershed that preserves one of the most

significant and near-pristine aquatic environments in the United States. Surface water

features in the GYA include lakes, ponds, rivers, and ice-free habitats.

About 10% of the GTNP is covered by surface water. Much of this is in five lakes along

the eastern front of the Teton Range, including Jackson, Jenny, Leigh, Two Ocean, and

Emma Matilda Lakes. About 100 alpine lakes exist, most above 9,000 feet. Many

streams originate in the Teton Range and in the Bridger Teton National Forest north and

east of the park, and drain into Jackson Lake or the Snake River. About 75 pothole

ponds of less than 0.5 acres to more than 35 acres occur in the glacial drift areas south

and east of Jackson Lake.

About 5% (112,000 acres) of Yellowstone is covered by water, including more than 220

lakes and 1,000 streams. Yellowstone Lake, which lies at an elevation of 7,730 feet

covers 136 square miles and is 400 feet deep, is the largest high elevation lake in North

America. The headwaters of five major river systems (Fall, Gallatin, Madison, Snake,

and Yellowstone) are either in or just upstream from YNP. The 670-mile Yellowstone

River, the longest undammed river in the lower 48 states, plunges 308 feet at the Lower

Falls in the Grand Canyon of the Yellowstone, almost twice the drop of Niagara Falls.

The Snake River originates on the western slope of the Continental Divide in northwest

Wyoming’s Teton Wilderness Area and flows about 450 miles through the upper Snake
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River Basin to south-central Idaho. From its headwaters, the river flows westward

through a portion of YNP, south through the Parkway and enters Jackson Lake within

GTNP boundaries. It flows east out of Jackson Lake and then south for about 25 miles

before crossing the south boundary of the park. The Buffalo Fork of the Snake River

enters GTNP from the east at Moran Junction.

Jackson Lake presently encompasses an area of 25,730 acres and is used to store water

for irrigation in Idaho’s Snake River Valley. The reservoir was first built in 1906 by

installing a dam at the outlet of the natural lake to create a usable capacity of 300,000

acre-feet. Usable capacity has been increased to 847,000 acre-feet through subsequent

dam replacements (NPS 1998).

Waters that remain ice-free because of river current or runoff from thermal features

provide important winter habitat for waterfowl, bald eagles, and water-dwelling

mammals. Similarly, YNP’s surface and groundwater resources support a world-class

trout fishery, and aquatic plant and animal communities.

The Snake River above and below Jackson Lake remains ice free, providing waterfowl

and year-round bald eagle habitat. Jackson Lake typically freezes over in mid-December.

Surface waters within GTNP are of exceptionally high quality and are designated as

Class I (the highest of four water quality classifications) by the State of Wyoming

Department of Environmental Quality (NPS 1998). Water quality characteristics of

Jackson Lake are typical of snowmelt-fed, high elevation reservoirs and are of relatively

high quality year-round. Water temperature, nutrient loading, and turbidity remain low

while dissolved oxygen averages are high. The Snake River downstream of the dam

exhibits the same high quality water observed in Jackson Lake (NPS 1998).

Similarly, water quality within YNP is considered excellent and surface waters are

designated Class I by the state. Water quality and quantity information is available for

the Yellowstone, Madison, Snake, Gibbon, Firehole, Lamar, and Gardner Rivers. As part

of fisheries investigations, the U.S. Fish and Wildlife Service collected chemical and

biological data on over 600 streams and 100 lakes in YNP, and has sampled aquatic

invertebrates on YNP’s five major lakes and 10 major rivers. YNP maintenance staff

monitors surface and ground water via 64 test wells near water and wastewater treatment

systems, underground storage tanks, and former landfills.

Natural processes and human activities have the potential to affect water quality in and

outside the parks. In YNP, about 16% of the park’s watershed is located outside park

boundaries. Although large areas are protected by wilderness designation, 5% remains

unprotected. External threats include leaching from tailings due to past mining activities

upstream of YNP. Within YNP, threats include involuntary discharge of untreated

wastewater, leaking underground storage tanks, sporadic hazardous materials spills

(primarily petroleum products), pollution from recreational boating, and backcountry

toilets near lakeshores and streams, leaching from abandoned dumps, and pollution from
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pesticide use. Natural influences include hydrothermal discharge, wildlife, fire, and

storm runoff.

Many of the lakes and streams in GYA are very weakly buffered against pH lowering

that could be induced by the addition of acidic rain or snowmelt. Many human activities,

roadways and visitor use areas parallel streams, rivers, and lakeshores. Winter

recreational activities, especially the discharge from 2-stroke snowmobile engines can

lead to indirect pollutant deposition into the top layer of snow and subsequently into the

associated surface and groundwater (Adams 1974; Ferrin and Coltharp 1974). Other

human activities that can impact water quality and aquatic and riparian habitats in the

GYA are timber harvest, road construction, flood control, grazing, mining, and

recreational development (GYCC 1999). Most such activities occur in areas that do not

drain into the parks’ surface water system.

A study conducted by Miller and Dustin (1997) was initiated over concern that the

quality of GTNP’s lakes may be declining due to increased human usage. Seventeen

lakes were sampled in 1995 and six were re-sampled in 1996 to determine the trophic

state of the lakes. In Jackson Lake, the waters are primarily oligotrophic (containing very

few nutrients), but may be slightly mesotrophic (containing moderate amounts of

nutrients) near developments using sewage lagoons such as Colter Bay. Two Ocean

Lake was found to be strongly mesotrophic.

Within GTNP, Snake River tributaries below the dam transport large concentrations of

suspended material during certain portions of the runoff period because of erosion of

unstable streambanks and overland flow during melt. Sediment constitutes the greatest

water quality concern for these streams (NPS 1998). As reported by Clark (1993) and

Maret (1995), sediment loading in the upper Snake River basin is caused by activities

such as road construction, off-road recreational vehicles, irrigated agriculture, land

development, and levee construction, most of which occurs down-stream from the park.

Levee construction on the Snake River near Jackson has contributed significantly to

channel alterations and sedimentation (Maret 1995).

Wetlands

Wetlands include marshes, bogs, streams, seeps, wet meadows, thermal pools, and

geysers found on high mountain slopes in valleys, and along lower elevation rivers. They

are some of the most diverse and productive parts of the parks’ ecosystems. Due to their

designation as national parks, YNP’s and GTNP’s wetlands are largely unimpacted.

However, where development has occurred in the parks (a total of 2% in YNP), it has

historically been placed in flatter, more easily traveled areas – along rivers and in

wetlands. Today, when possible, the parks are moving roads and facilities out of

wetlands and restoring them to natural conditions.

YNP’s wetlands have been mapped as part of the U.S. Fish and Wildlife Service’s

National Wetland Inventory, a congressionally mandated program to identify, classify,
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and map all wetlands in the United States. The predominant wetlands totaling over

118,500 acres (about 5% of the park) are classified as palustrine, and include wet

meadows, swamps, marshes, potholes, fens, bogs, and shallow ponds.

Before ground-disturbing activities such as construction, the landscape is mapped and

inventoried for wetlands so that the projects can be designed to avoid or minimize

adverse effects. Such detailed mapping has occurred along several road corridors and in

portions of most developed areas.

Wetlands are an important part of YNP’s river corridors and lake systems, and about

38% of the park’s 1,200 plant species are associated with wetlands. About 11% of the

park’s species grow only in wetlands, and one-half of the park’s rare plants are associated

with wetlands. YNP wetlands are also important to wildlife. An estimated 80% of

Wyoming’s native animals rely on wetlands, especially areas along rivers and creeks

(Consolo 1999).

The USFWS National Wetland Inventory (NWI) also covers GTNP. Mapping reveals

wetland areas throughout GTNP. The most extensive wetlands are found:

• Along the Snake River floodplain below Jackson Lake Dam;

• Along the Buffalo Fork of the Snake River;

• In the area called Willow Flats just north of the dam where Pilgrim Creek drains into

Jackson Lake;

• Along the Gros Ventre River; and,

• The Snake River inlet to Jackson Lake.

Wetlands in these areas are diverse, but are predominately classified as palustrine with

emergent, scrub/shrub, and aquatic bed characteristics (NWI; Cowardin et al. 1979).

These areas are dominated by emergent marshes, wet meadows, shrub wetland, short

woody vegetation areas, and ponds with floating or submerged aquatic vegetation.

Wetlands are an important component of the Snake River aquatic and riparian zones and

help create diverse wildlife habitat for prominent species of birds, such as the bald eagle,

trumpeter swan, great blue heron, and osprey (NPS 1997). Willow Flats supports diverse

bird and mammal populations in many riparian wetlands with willows and emergent

herbaceous vegetation interspersed with floodplain forest. Between Willow Flats and

Colter Bay Village on Jackson Lake are many ponds bordered by emergent wetlands

such as Swan Lake and Heron and Cygnet ponds.

Aquatic Resources

The parks are home to a vast array of native animals that depend on aquatic resources for

all or part of their lives – more than 400 types of aquatic insects, 12 fishes, 10 reptiles

and amphibians, at least 300 birds, 100 butterflies, and 60 mammals in YNP alone.

Fish are an important component of aquatic ecosystems. They link the transfer of energy

between aquatic and terrestrial environments. Over 20 species of fish, including
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nonnatives, are found in the parks; game species include trout and other salmonids. See

Aquatic Species: Reptiles, Amphibians, and Fish for a discussion of fish species of

special concern in the parks. Winter recreation does not appear to have any direct

impacts to fish and other aquatic resources; water pollution caused by toxic runoff from

the snowpack may be a greater concern.

Within YNP, aquatic invertebrates are abundant in both species and in total number, in

part because of the wide variety of habitats, including thermally influenced wetlands.

Invertebrate productivity in the Snake River in GTNP is slightly above average compared

to other western rivers. About 170 species have been collected and identified. Species

diversity is much lower on the Snake River between Jackson Lake Dam and Pacific

Creek than in areas downstream (NPS 1997).

Reptiles and amphibians occur in aquatic, thermal, or upland habitats. See Impact Topics

Dismissed, Reptiles and Amphibians, and Aquatic Species: Reptiles, Amphibians, and

Fish, in this chapter for discussions of these species.

Wildlife

Introduction

Winter for wildlife in the GYA is a challenging time for survival. High snow depths,

cold temperatures, and lack of high quality forage can lead to synergistic and nutritional

stress, and, consequently, intense competition and higher rates of mortality. Human

activities in the winter may compound these factors. The following sections describe the

species that winter recreation is most likely to affect. Several topics are discussed,

including population status or trend (if known), relevant life history data, and information

on winter habitat use.

Ungulate Winter Ranges

Ungulates rely on restricted winter ranges in which food and cover may be limited.

Consequently, major episodes of winter stress, low forage availability, and declining

physiological conditions lead to an increase in mortality (Meagher 1998). Competition is

particularly severe in winter, when thousands of large ungulates move to lower valley

elevations to forage on exposed vegetation in areas of low snow depth (Clark 1999). In

Jackson Hole, much of the ungulate winter range has been usurped by farming and

development, resulting in reduced habitat and conflicts with landowners (Boyce 1989).

Concern over the loss of elk winter range resulted in the creation of the National Elk

Refuge (NER) in 1912. Similarly, bighorn sheep historically wintered on the Gros

Ventre buttes and the east slopes of Rendezvous Peak (Whitfield 1983). These areas are

extensively developed and no longer are used by bighorns. Moose migrate from higher

elevations in and surrounding GTNP to the valley floors and canyon mouths where snow

depths are lower.

As managers of the Jackson elk herd, the Jackson Hole Cooperative Elk Studies Unit

believes that winter range is one of the most critical issues involving successful
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141

management of the second largest elk herd in the world. Adequate winter range reduces

the need for a feeding program (carried out by both Wyoming Game and Fish

Department and the NER), with its inherent costs and habitat impacts, and reduces the

risk of disease transmission, such as brucellosis.

In GTNP most elk and bison migrate to the NER feedgrounds; the remainder winter

along or east of the Snake River, primarily in areas with south- or west-facing slopes,

which accumulate less snow and are more prone to melting than other areas. Blacktail

Butte provides important winter range for both elk and moose. Up to 200 elk have been

observed there during late winter (Long, pers. com. 2000 ). Although the number of

moose in the area has not been quantified, they are common on the open west-facing

slopes throughout the winter. GTNP biologists have observed a gradual increase in

skiing and snowshoeing on Blacktail Butte, and are concerned about the effects of such

use on the wintering ungulates.

The Uhl Hill/Wolff Ridge area contains the densest over-wintering population of

ungulates in the Park. Periodic aerial surveys have shown significant elk use of the area

during the winter, with numbers ranging from 120 in 1996 to about 700 in 2000. During

the last two years, increasing numbers of bison have wintered in the Uhl Hill and Wolff

Ridge area. Before 1998, only 5 to 10 bison were located there during annual winter

bison classification surveys. Since that time, numbers have increased to 60 to 70 bison

(GTNP unpublished data).

Bison are highly social grazers, and develop traditional seasonal migration patterns

(Meagher 1989). In addition to using areas within YNP, bison also use winter ranges to

the west and north, and a small percentage move from the interior over Sylvan Pass and

down the Shoshone River. The YNP bison population uses three different wintering

areas: the Pelican Valley in the south-central portion of the park; Mary Mountain in the

Hayden-Firehole valleys in the west-central portion; and the Northern Range in the

Lamar Valley (Meagher et al. 1994).

In YNP, thermal areas are important components of winter range because warm ground

keeps these areas relatively free of snow, enabling bison and other ungulates to feed in

the otherwise snowbound interior of the park (Meagher 1970, 1971, 1976, 1978, 1985,

1998; Murie 1940; Miller 1968; Craighead et al. 1973; Ables and Ables 1987; NPS

1990). During severe winters, valleys supporting bison have either extensive thermal or

warm areas, or many small thermal areas among which bison movement is possible.

Most bison wintering areas in YNP contain streams that remain unfrozen because of a

warm water influx. Meagher wrote, “Scattered thermal sites—particularly warm ground

with less snow—apparently provide a margin for survival for bison in the harshest

wintering areas of YNP” (1978). During four aerial counts of bison in Hayden and

Pelican Valleys in December through March 1997-1998, bison were usually located in or

near thermal areas and along the banks of thermally influenced streams (Kurz 1998).
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Thermal areas with snow-free vegetation or shallow snow are very important winter

habitats for elk along the Madison, Firehole, and Gibbon Rivers (NPS 1990). A quarter

century ago, the Madison-Firehole elk herd in YNP was reported to have adapted to

deeper snow by using snow-free thermal areas that provided improved access to forage

(Craighead et al. 1973). In reporting on the herd of 800 to 1,000 elk residing in YNP’s

Madison-Firehole Valley, Ables and Ables (1987) wrote “. . . over-winter survival

depends heavily on thermal areas that reduce snow accumulations.”

Despite the more favorable habitat conditions provided by thermal areas, some animals

inevitably die each winter. In YNP winterkilled ungulate carcasses are concentrated in

thermal areas and both black and grizzly bears are known to use these areas upon

emerging from dens in spring (Green et al. 1997; Mattson 1997).

Ungulate Energy Budgets

Ungulates function at an energy deficit during winter because snow reduces forage

availability, affects an animal’s ability to escape predators, and increases energy costs at

a period of time when the nutritional value of winter forage is low (Beall 1974; Skovlin

1982; Mattfield 1974; Parker et al. 1984). Energy costs, expressed in calories expended

per unit of time for various activities, must be balanced by energy intake from foods that

provide necessary proteins, fats, and carbohydrates. Malnutrition may cause mortality

directly, or increase the risk of death by disease or predation.

Deep snow greatly increases the amounts of energy expended by deer and elk for

locomotion in YNP and elsewhere (Parker et al. 1984; Telfer 1978). DelGuidice et al.

found severe energy deprivation of elk in YNP to be associated with increased elk

density, deep snow cover, or both (1991). Craighead et al. reported that the MadisonFirehole elk herd had adapted to deeper snow in YNP by using snow-free thermal areas

that provided improved access to forage (1973). Elk feeding in thermal areas and snowfree areas near warm springs fed an average of about 11 hours per day. In comparison

Coughenour estimated that elk in snow (up to 60 cm deep) may require 16 hours of

feeding per day to meet their energy requirements (1994).

Aune (1981) described bison movements as appearing to be less restricted by snow than

elk movements. Bison primarily used a network of well-established trails and travel

routes, including riparian areas. Bison do use groomed and plowed roads, but use is

considered minor compared to off-road travel (Bjornlie 2000; Kurz et al. 2000; see

Chapter IV, alternative A). All these strategies help reduce energy expenditures to some

degree, and consequently, enhance Bison over-winter survival.

Bison (Bison bison)

Bison are native to the GYA, and were observed by early travelers before and after the

creation of YNP in 1872. In the 1870s and 1880s bison were nearly driven to extinction

by market hunting. In 1880, after nearly a decade of market hunting and poaching in the

park, the superintendent reported three herds totaling about 600 animals (Schullery and
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Whittlesey 1992). By 1902, the number of bison in the park had been reduced to 23

animals. Fearing extinction, park managers began a program to restore bison populations

in YNP. This program included the introduction of bison from captive herds to the park.

From the 1920s to the late 1960s, the bison in the park were subject to herd reductions

and other manipulation to achieve range management goals. In 1967, herd size for YNP

was 397 animals and a policy of natural regulation was established that allows bison and

other ungulates to reach population levels dictated by environmental conditions. The

bison population peaked at about 4,200 animals in summer 1994 (Meagher et al. 1994;

Meagher 1998), and was estimated at 2,200 animals in spring 1999.

As a consequence of significant increases in bison numbers and their corresponding

movements from YNP into Montana, periodic removals were resumed in 1990. The risk

of transmission of brucellosis—a contagious bacterial disease—from bison to cattle and

the economic cost associated with this risk prompted the development of bison

management plans. These interim management plans resulted in the shooting or capture

and slaughter of an average of 176 bison per year between 1990 and 1996. The interim

plan in place during the severe winter of 1996-1997 resulted in the shooting or capture

and slaughter of 1,084 bison (NPS 1998).

In May 1998 a draft EIS/Plan for the Interagency Plan for the State of Montana and YNP

was published for public comment (NPS 1998). The draft EIS/Plan analyzed impacts of

seven alternatives for the interagency, long-term management of YNP area bison to

maintain a wild and free-ranging bison population, and address the risk of brucellosis

transmission to protect the economic viability of the livestock industry in Montana (NPS

1998). More than 67,500 letters were received on the draft Bison Management EIS/Plan.

The comments will be used by the NPS, the co-leading agencies (the U.S. Forest Service

and the State of Montana), and the cooperating agency (the U.S. Animal and Plant Health

Inspection Service) to revise the draft EIS (NPS 1998). A Final Environmental Impact

Statement/Plan for bison management will be released in summer 2000.

Long-term data suggest that the YNP bison population has steadily increased from the

herd control days of the late 1960s. According to Dr. Mary Meagher, bison researcher in

YNP, the population reached carrying capacity early in the winter of 1981-82 at about

2,400 animals. Consequently, bison began expanding their range, using the snowpacked groomed roads to facilitate dispersal into new areas. Major movements occurred

from the Pelican Valley into Hayden Valley, resulting in an increase of animals in

Hayden Valley, and subsequently an increase in movements westward to the Firehole

Valley (Meagher 1993; Meagher et al. 1994; Meagher 1998). As a consequence of this

range expansion, the population roughly doubled between 1982 and 1994. As a result,

according to Dr. Meagher, bison habitats in YNP are of decreased quality, and can no

longer support the same numbers of bison as before 1981. Consequently, Meagher

contends that the population will be driven downward as bison leave the park, partially

using groomed roads, where they are consequently removed by management actions to

control the transmission of brucellosis.
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Cheville et al. (1998) presents an alternative interpretation of the population data. They

conclude that the population growth rate and range expansion did not increase as a

consequence of the groomed road system. Rather, range expansion is an artifact of a

population that does not regulate naturally. They concluded that even in the absence of

groomed roads, it would be unlikely that natural mortality would eliminate the egress of

bison from the park. Other researchers dispute Meagher’s claim of range expansions into

the Firehole, Madison, and Hayden Valleys, stating that these areas were traditionally

used by bison since at least the early 1970s (Craighead et al. 1973; Aune 1981). Aune

asserts that the actual range expansions observed since the winter recreation program

include increased movements out of the northern area (where no groomed routes exist)

and into Cougar Meadows and West Yellowstone, which began in the late 1970s before

the road grooming program (1981). Recent work by Bjornlie (2000) and Kurz et al.

(2000) also conflicts with the results of Meagher’s research, indicating that at present,

bison do not use groomed roads for major shifts in distribution (see Chapter IV,

alternative A).

Management removals (to prevent the transmission of brucellosis to cattle) and severe

winter conditions are the main causes of bison mortality. Bison die during major

episodes of winter stress, low forage availability, and declining physiological conditions

(NPS 1998). Their carcasses are scavenged by many species, including mammals, birds,

and insects, and thus play an important role in the ecology of the parks (NPS 1998). In

particular, bison carcasses provide protein for threatened species including grizzly bears,

bald eagles, and gray wolves (Swenson et al. 1986; Green et al. 1997; Smith et al 1998).

In GTNP the Jackson bison herd grew from 16 founders in 1969 to 500 animals by 1999.

Because 95% of the herd winters on the NER and the remainder occur in areas that are

either closed or otherwise restricted to the public, impacts to bison from winter recreation

in GTNP are not of great concern. However, during the past several years increasing

numbers of bison wintered in the Uhl Hill and Wolff Ridge area. Continued unregulated

nonmotorized use could affect them. Research is ongoing as to the effects of brucellosis

on this exposed herd, including the extent to which the disease influences population

productivity (Cain et al. 2000).

Elk (Cervus elaphus)

Elk once roamed throughout most of North America. By the early 1890s, elk populations

were decimated by commercial harvest, competition with livestock, and habitat change

(Clark 1999). All remaining large herds were in the GYA. Elk are the most abundant

ungulate species in the YNP area with an estimated 50,000 to 60,000 elk in eight to ten

separate herds (USFWS 1994). The northern YNP elk herd, the largest in the YNP area,

summers in the north, east, and central portions of the park and surrounding mountains

and winters in the northeast, north, and west areas of the park and adjacent lands. Three

herds are found west and northwest of YNP including the Madison-Firehole, GallatinMadison, and Gallatin Range herds. East of YNP are the Clark’s Fork, North Fork-
WILDLIFE

145

Shoshone, and Carter Mountain herds, and south are the Jackson Hole, Targhee, and

Sand Creek herds (Clark 1999).

Elevation, topography, weather, vegetation, and escape cover determine elk habitat.

Summer range is extensive and reflects vegetative productivity. Winter range is more

limited and is determined by lower elevation and snow depth. Elk generally forage on

grasses followed in preference by browse species and conifers (Clark 1999).

Because of natural mortality, elk, like bison, play an important role in the ecological

processes of the YNP area. Elk are either preyed upon or their carcasses scavenged by

many wildlife species. Carcasses provide an important source of protein for threatened

species including grizzly bears, bald eagles, and gray wolves (Swenson et al. 1986; Green

et al. 1997; Smith et al. 1998).

The elk in GTNP are considered part of the Jackson elk herd. In addition to the park, the

summer range of the Jackson herd includes the Teton Wilderness, the southern part of

YNP, and the Gros Ventre Range. Most winter range occurs in the Buffalo Fork Valley,

Gros Ventre Range, and NER. In addition four feedgrounds provide supplemental winter

forage, three of which are found in the Gros Ventre River drainage and one on the NER.

About 80% to 90% of the herd is associated with these feeding areas during the winter

(NPS 1995).

Many of the elk that summer in the Teton Wilderness and southern YNP migrate through

the Parkway and GTNP in the spring and fall. About 200 to 400 remain in the park

throughout the winter along the Snake River floodplain and along the east side foothills

(NPS 1980). Few elk winter in the Parkway because of deep and persistent snow.

To manage the size of the Jackson elk herd, elk hunting is allowed in specific areas of

GTNP east of the Snake River and throughout the entire Parkway. Elk hunting limits the

number of Grand Teton elk on the NER during winter and reserves winter range for herd

segments that summer outside the park. Hunting also helps achieve the herd objective set

by the Wyoming Game and Fish Department of 11,000 animals.

Moose (Alces alces)

In YNP moose occur at low densities. Although no population estimates exist for moose,

recent studies indicate a population decline in areas where recent landscape-level fires

have affected old-growth lodgepole pine winter range. Potential changes in deciduous

vegetation, especially willows (Salix spp.) in riparian areas may also affect moose winter

foraging and population levels (Tyers and Irby 1995). Future population trends are

uncertain and may vary due to habitat conditions, exposure to predation, and human

influences (Tyers 1999).

In GTNP moose were rare or absent before about 1912, but were numerous by 1950.

During the mid-1960s, 200 to 250 moose were year-round residents of the valley areas in

the park and the adjacent Buffalo Valley. This segment of the Jackson moose population
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increased to 700 to 900 during winter when moose migrated onto winter range from other

areas inside and outside the park. The parkwide population during summer is unknown,

but most moose that summer within the park probably remain for the winter (NPS 1995).

Moose that spend the summer at high elevations move downslope to river bottoms and

sagebrush flats, where they are abundant and highly visible residents of the park in the

winter. Areas that provide important winter habitat include the Willow Flats/Hermitage

Point area, Buffalo Valley, and the Snake and Gros Ventre River corridors. All or

portions of the three areas are closed to winter use to protect wintering moose and other

wildlife. The winter distribution of moose in the parks corresponds to areas where deep

snow and harsh winter conditions exist.

Bighorn Sheep (Ovis canadensis)

Bighorn sheep were historically found throughout the western mountains of North

America. However, populations have dramatically declined throughout their range.

These declines are associated with competition with livestock, introduction of disease,

hunting, and loss of habitat during settlement of the West. In YNP the bighorn sheep

population ranges from 240 to 325, and winter ranges are located in the northern part of

the park (Legg 1998).

In GTNP bighorn sheep are found in isolated bands at high elevations along the western

park boundary and among the major peaks. Known as the Teton herd, it is comprised of

two sub-populations: one in the north, west of Jackson Lake; and one in the south, west

of Phelps Lake. The entire herd is a marginally viable, remnant population that is

geographically isolated from other herds and persists in a harsh environment. There may

be limited interchange between the two sub-populations. A separate, small population

occurs on the Bridger-Teton National Forest in the Gros Ventre River drainage (NPS

1995).

Some herds of bighorn sheep use different ranges in winter and summer. Winter range is

more limited than summer range and typically occurs at lower elevations. Sheep use

traditionally formed migration patterns. Any alteration to these routes or habitats could

be detrimental for a population of bighorn sheep (Legg 1998). To protect bighorn sheep

from human disturbance, several areas currently are closed to public entry: McMinn

Bench in YNP and Kelly Hill and Static Peak in GTNP.

Reptiles and Amphibians

The valley garter snake (Thamnophis sirtalis fitchi) and the wandering garter snake

(Thamnophis elegans vagrans) are semi-aquatic. Consequently, water pollution caused

by toxins in the snowpack may be of concern. Direct impacts are not expected to occur

because these species hibernate for the winter use period. See Aquatic Species: Reptiles,

Amphibians, and Fish and Impact Topics Dismissed for discussions of the other reptiles

that inhabit the parks.
FEDERALLY PROTECTED SPECIES

147

The Columbia spotted frog (Rana luteiventris), boreal chorus frog (Pseudacris

maculata), blotched tiger salamander (Ambystoma tigrinum melanostictum), and

introduced bullfrog occur in the parks. Amphibians hibernate and, therefore, are not

directly affected by winter use. Water pollution caused by toxins in the snowpack may

be a greater concern. See Aquatic Species: Reptiles, Amphibians, and Fish for a

discussion of amphibian species of special concern, and Impact Topics Dismissed for a

discussion of the bullfrog.

Federally Protected Species

The ESA requires an examination of impacts on all federally threatened or endangered

species. Four species protected under the ESA are present in the parks in the winter.

Threatened species include the Canada lynx (Lynx canadensis), bald eagle (Haliaeetus

leucocephalus), and grizzly bear (Ursus arctos horribilis); the gray wolf (Canis lupus) is

considered experimental, nonessential. Species classified as experimental, nonessential

are considered not necessary for the continued existence of the species and critical habitat

is not designated. This classification allows management actions that may involve lethal

control or relocation. Section 7 of the ESA requires the preparation of a biological

assessment (BA) that analyzes the impacts of the proposed action on listed species. A

BA has been prepared, and portions of it are reproduced in this section.

Grizzly Bear (Ursus arctos horribilis)

In the contiguous United States, grizzly bears were extirpated from about 98% of their

historical range between 1850 and 1950 through human-caused mortality (USFWS

1993). In 1975, they were listed as threatened under the ESA and recovery zones and

goals were subsequently established (USFWS 1993). Since then, annual population

estimates for the Yellowstone population have increased largely due to lower numbers of

human-caused adult female mortality.

The life history of the grizzly bear is well documented (McNamee 1984). This

discussion is limited to grizzly activities that coincide with winter use: the time

surrounding and including denning. In the middle to late fall, grizzlies feed on the seeds

of whitebark pine (Pinus albicaulis), and they scavenge on ungulates that died during the

rut or gut piles associated with the hunting season (Mattson and Jonkel 1990; Mattson et

al. 1991). The availability of these foods and weather conditions influence the initiation

of denning (Craighead 1979). During years of ample food, mild temperatures, and low

snow cover, grizzlies tend to den later in the season. Based on 14 years of den entry data

for grizzly bears in the GYA, about 90% of all grizzlies are denned by the end of

November (Haroldson et al. in prep.). In one study grizzly bears were documented to

frequent the immediate area of their dens from 8 to 22 days before denning (Judd et al.

1986). Dens were often located at sites with whitebark pine and subalpine fir at an

average elevation of 8,100 feet (range: 6,500 to 10,000 feet), and were found on north

slopes ranging from 30° to 60° slope range (Judd et al. 1986).
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Bears emerge from their dens when temperatures rise and food availability increases

(e.g., winter-killed ungulates or spring vegetation). Consequently, when spring arrives

early and melting snow exposes green vegetation and carcasses, bears may emerge from

dens earlier in the season (Craighead 1979). First to emerge are adult males between

mid-February and late March, followed by subadults and solitary females in late March

or early April; lastly females with new cubs emerge between early and mid-April

(Haroldson et al. in prep). From March through May, ungulate carrion (primarily elk and

bison) is the most important grizzly food (Mattson et al. 1991). Bears also feed on

emerging vegetation on lower elevations, wind swept slopes, and in thermal areas.

Grizzlies may also consume over-wintered whitebark pine seeds if seed production was

abundant the previous fall (Mattson et al. 1992).

Grizzly bears are found throughout YNP. In GTNP and the Parkway, grizzly bears have

increased from relatively uncommon to common in the last 10 years, in conjunction with

a steady trend toward increasing bear density in the southern GYA. Home ranges of 27

radio-collared bears from 1975 to 1998 have included parts of GTNP and the Parkway.

Grizzly bears are now common in the Gros Ventre Mountains on the southeastern border

of GTNP, and southeast to the upper Green River basin. In the Teton Range, they are

regularly sighted north of Moran Canyon and the Badger Creek drainage, where visitor

use of the backcountry occurs at relatively low levels. On the Jackson Hole valley floor,

they are common north of the Triangle X Ranch, and have been observed in the Snake

River drainage on several occasions. Grizzly bears also occur in the Two Ocean Lake

area and throughout the Parkway.

Gray Wolf (Canis lupus)

The subspecies of the northern Rocky Mountain wolf (Canis lupus irremotus) was

initially listed as an endangered species in 1973 (38 FR 14678). Due to taxonomic

concerns, the entire species was listed as endangered in the contiguous United States

outside of Minnesota, where it was listed as threatened in 1978 (43 FR 9607). In 1990

Congress directed the appointment of a Wolf Management Committee to develop a plan

for wolf restoration in YNP and central Idaho. The following year, Congress directed the

United States Fish and Wildlife Service (USFWS) to prepare an EIS to consider the

reintroduction of wolves into these areas (USFWS 1994b). The final EIS was completed

in May 1994, and the final rules for the reintroduction were published in November 1994

(59 FR 60252). Wolves reintroduced into YNP and central Idaho are classified

nonessential, experimental according to section 10(j) of the ESA of 1973, as amended

(16 U.S.C. 1531). In national parks and wildlife refuges, nonessential, experimental

populations are treated as threatened species, and all provisions of Section 7 of the ESA

apply (50 CFR 17.83(b)). All wolves occurring in the State of Wyoming are classified as

nonessential, experimental (59 FR 60256).

Wolf packs occur throughout the central GYA, including areas north and east of the

parks. In 1998, wolf pack territory sizes averaged 359 square miles (range: 135 to 955
FEDERALLY PROTECTED SPECIES

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square miles) (Smith et al. 1998). There are currently 11 packs with 8 breeding pairs in

the GYA (Smith, pers. com. 2000). Wolf winter range is located in areas with high prey

concentrations. As a consequence, ungulate winter range is closely associated with wolf

activity. Depending upon prey abundance, wolves may occupy a variety of habitats

including grasslands, sagebrush steppes, coniferous and mixed forests, and alpine areas.

Wolves dispersing from YNP began to occur in GTNP in 1997. The Teton Pack

(formerly the “Teton Duo”) and the Gros Ventre Pack (formerly the “Jackson Trio”)

ranged widely throughout the park during the winter of 1998-99. Both packs and the

Soda Butte Pack used the Pacific Creek drainage as a corridor between YNP and GTNP.

The Teton Pack moved much less than the other two packs, remaining primarily in the

northeast part of the park, where they denned in the spring of 1999 producing pups. On

June 21, 1999, the male was found dead on Highway 26/287, having been hit by a

vehicle. During the winter of 1999-2000, the female and her five pups alternated among

the northeast corner of the park and the Gros Ventre River Basin (primarily outside of the

park). The Gros Ventre Pack denned in the Gros Ventre River drainage outside GTNP

producing two pups. During the winters of 1998-99 and 1999-2000, the pack principally

hunted in the NER, the Upper Gros Ventre River basin outside of the park, and the area

around the small community of Kelly (within the park). The Soda Butte Pack has not

been located within the park since May of 1999. Uncollared black wolves have been

reported in the Moran area since 1997.

Bald Eagle (Haliacetus leucocephalus)

The bald eagle was listed as an endangered species in Wyoming in March 1967 under the

Endangered Species Preservation Act of 1966 (32 FR 4001), and listed in 1978 under the

ESA of 1973 (43 FR 6233). The Pacific States Bald Eagle Recovery Team was formed

as a result of the 1978 listing and a recovery plan was completed in 1986 (FWS 1986).

The parks lie within the Greater Yellowstone Recovery Area (Zone 18 in the Recovery

Plan). As a result of the implementation of recovery plans, populations of bald eagles

began to increase by the mid-1980s. Consequently, the status of the bald eagle was

changed from endangered to threatened in Wyoming in July 1995. Recovery goals were

subsequently met, and in July 1999 the USFWS announced a proposal to remove the bald

eagle from the endangered species list. No final action on the proposal to delist has

occurred to date. The bald eagle is a “species of special concern” in the parks, and is also

afforded protection under the Migratory Bird Treaty Act (MBTA) 16 U.S. Code 703 of

1918, and the Bald Eagle Protection Act 16 U.S. Code 668 of 1940.

Before its listing as an endangered species in 1967, about 30 to 35 occupied nesting

territories of bald eagles were known in the GYA (Greater Yellowstone Ecosystem Bald

Eagle Working Team 1983). Between 1970 and 1995 the bald eagle population in the

GYA increased exponentially (Stangl 1999), reaching over 100 known occupied

territories (Greater Yellowstone Bald Eagle Working Group 1996). In 1998 118

breeding territories were known, of which 105 were occupied. Population growth has
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been attributed to a significant reduction in the level of environmental contaminants such

as DDT, and the protection of nesting habitat (Stangl 1999).

GTNP contains 10 known nesting territories and pairs; however, not all pairs nest in the

park each year. Known territories are located along the shorelines of the Snake River and

Jackson Lake. No bald eagles are known to nest within the Parkway, although the upper

Snake River is used extensively for foraging year-round (Alt 1980). Bald eagles that nest

along the Snake River in GTNP may remain on their nest territories throughout the year,

occasionally leaving for short periods during the non-breeding season to exploit abundant

or ephemeral food sources elsewhere. Lake-nesting birds may remain on territory for

most of the time that Jackson Lake is free of ice. Other winter foraging areas in GTNP

include the Buffalo Fork River and Cottonwood Creek.

In YNP, 26 bald eagle nests produced 14 young in 1999. Most of these nests were

located on the shoreline of Yellowstone Lake. After the lake freezes, eagles may move

north to feed on winterkilled ungulates on the Northern Range, or to take advantage of

gut piles associated with the fall and winter hunt outside the park. Other eagles occur in

thermally influenced areas, or near rivers that remain ice-free such as the Yellowstone

and Firehole (NPS 1997).

Some resident adult eagles remain in the parks as winter approaches, and others migrate

short distances depending on food availability. During the winter, large numbers of

migratory eagles join resident eagles, with up to a 45% influx reported in some years

(Stangl 1999). In general, bald eagle winter habitat is associated with areas of open

water where fish or waterfowl congregate (Swensen et al. 1986), or ungulate winter range

where eagles scavenge on carcasses of large winterkilled mammals.

Bald eagle management in the parks includes conducting annual nest surveys, monitoring

territory occupancy and productivity, and banding nestlings. YNP also conducts annual

mid-winter bald eagle surveys to count eagles and map their distribution. In addition

each year beginning February 15, GTNP enforces a 0.5-mile buffer zone around active

bald eagle nests along the Snake River to provide protection from human disturbance.

Nest building or repair intensifies around this time followed by a 35-day incubation

period from February through March (Swensen et al. 1986; Harmata and Oakleaf 1992;

Stangl 1994). The majority of nesting territories are located along major rivers or lakes

within 5 km of their inlets or outlets, or along thermally influenced streams or lakes (Alt

1980). Nests and roosts commonly occur in mature and old growth trees in multi-layered

stands of Douglas-fir (Pseudotsuga menziesii), black cottonwood (Populus trichocarpa),

and spruce (Picea spp.). Nearby food, suitable perches, and security from human

activities are important habitat components for both nest and roost sites.
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Canada Lynx (Lynx canadensis)

The USFWS proposed to list the Canada lynx as a threatened species under the ESA in

July 1998 (63 FR 36993). In doing so USFWS concluded that the lynx population in the

United States is threatened by human alteration of forests, low numbers as a result of past

exploitation, expansion of the range of competitors (particularly bobcats and coyotes),

and elevated levels of human access into lynx habitat (63 FR 36994). In July 1999 the

USFWS extended the normal 12-month rule-making process an additional six months to

allow for the consideration of new scientific information and additional public comments

(64 FR 36836). A final ruling, issued in March 2000, declared the lynx a threatened

species.

In Wyoming, lynx occur primarily in spruce-fir and lodgepole pine forests at slopes of 8°

to 12°, at elevations between 7,995 and 9,636 feet (USFS 1999). Aspen (Populus

tremuloides) stands and forest edges, as well as open grass meadows and edges with

forests, may also support high numbers of lynx. On a landscape scale, lynx habitat

includes a mosaic of early seral stages that support snowshoe hare (Lepus americanus)

populations, their primary prey, and late seral stages of dense old growth forest that

provide ideal denning and security habitat. Connectivity between lynx populations is

critical. Dispersal corridors should be several miles wide with only narrow gaps. Large

tracts of continuous coniferous forest are the most desirable for lynx travel and dispersal

(Tanimoto 1998).

Although reliable information concerning the abundance and distribution of lynx is

lacking, Consolo and Meagher documented 50 sighting and track reports of lynx in YNP

from 1893 to 1995 (1999). Most sightings and records of tracks occurred after 1930.

From 1995 to present, five sightings of lynx were reported in YNP, three on the Northern

Range and two in the park interior (Gunther 1999). However, many of these sightings

were not verified and consequently their credibility is questionable. In particular lynx are

easily confused with bobcats by inexperienced observers. In the 1990s numerous

researchers conducted studies to document the presence of rare carnivores in YNP; none

detected lynx (Harter et al. 1993; Gehman et al. 1994; Gehman and Robinson 1998;

Murphy 1998).

Little information on lynx abundance and distribution is available for GTNP and the

Parkway. GTNP files include only 12 unverified reports (GTNP files). A transect survey

of 169 km at nine locales in northern GTNP and vicinity in 1998 found no sign of lynx

(Wyoming Game and Fish Department, Plata, pers. com. 2000).

Lynx are solitary carnivores generally occurring at low densities in boreal forest habitats.

Within most of their range, lynx densities and population dynamics are strongly tied to

the distribution and abundance of snowshoe hare. However, this relationship may be

muted or absent in more southern populations (Halfpenny et al. 1982). Females may not

reproduce during food shortages, and food availability directly correlates with the

survival of young lynx with few kittens surviving when food is scarce (Koehler 1990).
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Kittens are born in May or June after a 60- to 74-day gestation period, and typically

remain with their mothers until about 10 months of age.

Species of Special Concern

NPS policy requires examination of the impacts on park species of special concern,

defined as those species for which data are sufficient to document that the species is in

decline, or species that because of their unique or highly localized habitat requirements

warrant special management. Most species of special concern are not winter residents of

the parks, and thus are unaffected by winter use. Therefore, the following accounts

describe only those park-designated species of special concern that occur in the parks

year-round and for which winter use may be detrimental.

Wolverine (Gulo gulo), Fisher (Martes pennanti), American Marten (Martes

americana), and River Otter (Lutra canadensis)

Wolverines and fishers are considered rare in the YNP area and both are classified as

species of special concern in Wyoming, Montana, and Idaho, and sensitive in Regions 1,

2, and 4 of the U.S. Forest Service. American martens, more common in the YNP area,

are classified as sensitive in Region 2 of the USFS. They are also classified as an

“indicator species” of old growth forests by the USFS (Trochta 1999). River otters are

common and classified as a species of special concern by Wyoming, Montana, and Idaho.

Wolverines occur in low-density populations and are one of the least studied carnivores

in North America. To date only five comprehensive studies have described wolverine

ecology in North America (Hornocker and Hash 1981; Gardner 1985; Magoun 1985;

Banci 1987; and Copeland 1996). Historical reductions in the distribution of wolverines

correlate with the encroachment of human civilization and suggest the species is

especially sensitive to environmental perturbations and to local extinction (Banci 1994).

The most southerly productive population of wolverines in North America may occur in

Grand Teton National Park. Ongoing research (Copeland 1999) is tracking the

movements of radio-collared wolverines along the western border of the park and on the

adjacent Targhee National Forest. In YNP there are enough sightings and reports to

suggest that the park also supports a wolverine population. From 1887 through 1998, 93

unconfirmed and 51 confirmed reports and sightings of wolverine have been documented

in YNP (Gunther 1999).

Wolverines are associated with remote, boreal habitats that correlate with the absence of

humans (Copeland 1999). Adequate year-round food supplies (especially ungulate

carrion) may be more important than particular types of topography or plant associations

(Banci 1994). Rocky outcrops or trees may be used for escape and cover.

Female wolverines in Idaho appeared to initiate denning in late February (Copeland

1996). Dens were located in subalpine cirque basins above 8,000 feet and were

surrounded by trees. Natal dens in Montana were most commonly associated with snowcovered tree roots, log jams, or rocks and boulders (Hash 1987). In Idaho wolverines
SPECIES OF SPECIAL CONCERN

153

abandoned natal dens as early as March 10, moving kits through a series of maternal dens

until weaning (Copeland 1996). Human disturbance may be the cause of den

abandonment (Copeland 1996; Myberget 1968; Pullianian 1968), although Magoun

(1985) stated that snow melt may be a factor as female wolverines in arctic Alaska did

not appear disturbed by human activity.

Sightings and reports of fisher are extremely scarce in the parks. Only 4 confirmed and

11 unconfirmed reports were documented in YNP between 1887 and 1998 (Gunther

1999). In GTNP 13 unverified reports were received between 1984 and 1997 (GTNP

files).

Fishers are associated with dense, closed canopy forests. They avoid meadows, clearcuts, and areas of deep snow. They travel on packed snow trails. Brush piles, root wads,

snags, and hollow logs provide cover. Breeding occurs from early March to late April,

and the young are born in the cavities of large diameter trees (Trochta 1999). Fishers are

opportunistic feeders, preying on snowshoe hares, porcupines, rodents, and carrion

(Gunther et al. 1997).

American martens occur in all three parks, although the 1988 fires in YNP destroyed a

large proportion of marten habitat (Clark et al. 1989). Preferred habitat includes oldgrowth spruce-fir and lodgepole forests with a well-established understory and woody

debris. They also use meadows, rocky areas, and forest edges (Clark et al. 1989). Young

are born in mid-March to late April in dens and disperse in late summer or early fall

(Clark et al. 1989; Trochta 1999).

Inhabiting a variety of aquatic habitats, river otters occur in many of the lakes and

streams in the parks (Clark et al. 1989). Unpolluted aquatic systems and intact riparian

areas are essential to river otters’ continued existence. Young are born in March or

April, in the dens of other species (e.g., beaver) or in natural shelters close to water.

Slow-swimming fish species are the otter’s main prey. They also consume small

mammals, amphibians, aquatic insects, reptiles, and birds (Clark et al. 1989).

Trumpeter Swan (Cygnus buccinator)

The trumpeter swan is a species of concern in Idaho and Montana, and a Priority 1

species in Wyoming. In 1989 the Idaho Chapter of the Wildlife Society unsuccessfully

petitioned the USFWS to list the trumpeter swan in the GYA (the Rocky Mountain

Population) as threatened under the ESA. Concern over the dramatic decline of this

population led to the establishment of the Greater Yellowstone Trumpeter Swan Working

Group in 1997 (Olliff 1999).

Trumpeter swans inhabiting the parks are a part of the Rocky Mountain Population

(RMP). The RMP is comprised of 2 separate breeding flocks: the more sedentary U.S.

segment which includes swans occupying parts of southeast Idaho, southwest Montana,

and northwest Wyoming (referred to as the Tri-state Area), and the migratory Canadian
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segment (Subcommittee on Rocky Mountain Trumpeter Swans 1992). Swans in the Tristate Area face competition for winter forage from the nonresident Canadian flocks,

contributing to high over-winter mortality, especially for juvenile birds (Subcommittee

on Rocky Mountain Trumpeter Swans 1992). Swans return to breeding territories

between February and May and hatch young around late June (Olliff 1999).

Winter habitat consists of ice-free areas throughout the parks. In YNP, thermal areas

contribute to the maintenance of open water, but its availability may become scarce

during extremely cold weather (NPS 1990). Portions of the Madison, Firehole, and

Yellowstone Rivers (among other sites) provide wintering habitat for swans in YNP

(McEneaney, pers. com. 2000). In GTNP the Snake River is a critical wintering habitat

for swans, especially when other wintering sites around the valley have frozen over

(Reid, pers. com. 2000). Portions of the Snake River corridor are closed to public use

during the winter to protect winter habitat for species such as the trumpeter swan. In

addition where appropriate and posted, public access is restricted within 250 yards of

nesting sites from February 1 to September 15.

Aquatic Species: Reptiles, Amphibians, and Fish

Two reptile species are of special concern in the parks. The northern sagebrush lizard

(Sceloporus graciosus graciosus) is found at elevations up to 8,300 feet, and is

commonly associated with thermal areas (NPS 1998). Sagebrush lizard habitat may be

disturbed if development occurs in rocky areas along the fringes of thermal areas. The

rubber boa (Charina bottae) is a semi-aquatic snake. Consequently, water pollution

caused by toxins in the snowpack may be of concern. Direct impacts to either of these

species are not expected to occur because they hibernate for the duration of the winter

use period. See Impact Topics Dismissed and Reptiles and Amphibians for discussions of

other reptiles in the parks.

Amphibian species of special concern in the parks are the boreal toad (Bufo boreas

boreas) and the northern leopard frog (Rana pipiens). The boreal toad is known to have

declined in abundance in the parks, and the northern leopard frog, historically

documented to breed in the parks, is now rarely seen (Koch and Peterson 1995). Both of

these species inhabit a wide range of aquatic habitats, including ponds, lakes, and

wetlands. Because these species hibernate, they are not directly affected by winter use.

Water pollution caused by toxins that accumulate in the snowpack may be a concern

more than possible direct impacts. See Reptiles and Amphibians in this chapter for a

discussion of the other amphibians in the parks.

Fish species of special concern in the parks include the arctic grayling (Thymus arcticus);

the leatherside chub (Gila copei); the westslope cutthroat trout (Oncorhynchus clarki

lewisi); the Snake River cutthroat (Oncorhynchus clarki); and the Yellowstone cutthroat

trout (Oncorhynchus clarki bouvieri).
NATURAL SOUNDSCAPES

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The arctic grayling inhabits lakes in YNP (Clark et al. 1989). It prefers cold, clear water

with abundant vegetation, and spawning occurs from April to mid-June. Young grayling

feed on zooplankton, switching to invertebrates as they mature. Threats to the arctic

grayling include competition from exotic fish and habitat alteration.

The morphologically distinct Snake River cutthroat trout is only found in the Jackson

Hole area of the Snake River. Spawning occurs in tributaries where success is highly

dependent on local conditions. Threats to the Snake River cutthroat trout populations

include barriers to migration, turbidity, lack of cover, livestock pollution, water and flood

control development, irrigation, and fishing pressure (NPS 1997).

Considered by the Wyoming Game and Fish Department to be a distinct subspecies from

the Snake River cutthroat, the Yellowstone cutthroat trout inhabits Yellowstone Lake and

its tributaries, and may occur into the alpine zone. They are adapted to cold temperatures

but have been found in geothermally influenced waters (Clark et al. 1989). Spawning

occurs in streams, in the latter part of April through early August. Depending upon their

age, these trout consume plankton or invertebrates. In YNP, the Yellowstone cutthroat is

threatened by the nonnative lake trout (Salvelinus namaycush), and whirling disease

caused by a parasite that attacks the cartilage of young fish. In a petition to list the

Yellowstone cutthroat under the ESA, the petitioners included the Snake River cutthroat

as a form of the Yellowstone subspecies.

Occurring in YNP, the westslope cutthroat trout inhabits mountain streams and mainstem

river systems (Clark et al. 1989). Adult westslope cutthroats prefer large pools and other

low velocity areas. They are migratory, traveling up tributaries to spawn from April to

July depending upon elevation and spring runoff. All westslope trout in YNP show some

degree of hybridization with other cutthroat trout species and rainbow trout.

Hybridization can lead to the loss of locally adapted populations (Clark et al. 1989).

Other threats to the westslope cutthroat include predation and competition from

nonnative fish, and fishing pressure. The USFWS recently determined this species did

not warrant listing under the ESA (65 Fed. Reg. 20120, April 14, 2000).

The leatherside chub exists in the Snake River near the mouth of the Buffalo Fork River

(NPS 1980; Maret 1995; NPS 1998). Although native to other parts of the state, the

leatherside chub may have been introduced to the Snake River during the last sixty years.

See Aquatic Resources, in this chapter for a brief discussion of other fish species.

Natural Soundscapes

An important part of the park service’s mission is to preserve or restore the natural

soundscapes associated with units of the national park system. The natural soundscapes

(also referred to as natural quiet and the natural ambient sound level) are the unimpaired

sounds of nature, and are among the intrinsic elements of the environment that are

associated both with the purpose of a park and its natural ecological functioning. They

are inherent components of “the scenery and the natural and historic objects and the
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wildlife” protected by the NPS Organic Act. Natural sounds and tranquility are major

resources of many national parks and are valued by visitors. Increasingly, even parks

that appear as they did in historical context do not sound like they once did. Natural

sounds are being masked or obscured by a wide variety of human activities. NPS policy

is to facilitate, to the fullest extent practicable, the protection, maintenance, or restoration

of the natural soundscape resource in a condition unimpaired by inappropriate noise

sources. Every visitor who so desires should have the opportunity to enjoy natural

soundscapes and to hear the sounds of nature without impairment.

Appendix C contains regulatory references and excerpts of park service definitions and

policies regarding sound and natural quiet in national parks.

Sound Levels, Sound Level Changes, and Audibility

The volume of a sound is measured by its sound pressure level in units of decibels (dB).

A given sound can consist of a single tone, such as a bird chirp, or a wide range of sound

frequencies, such as the wind through the trees. Some sound sources can have sounds in

many frequencies, but are particularly loud in certain frequency ranges, such as

snowmobiles with their characteristic sound centered around the frequency of 200 hertz

(Hz).

Human ears do not hear all frequencies equally well: low frequencies and very high

frequencies are attenuated by human hearing. Human ears are particularly sensitive to

the relatively high frequency range of 1,000 Hz to 4,000 Hz. When the sound is

measured, electronic filters in the measurement equipment are typically used to simulate

the human ear’s response. The most commonly used set of filters is referred to as the Aweighting network. Sound pressure levels that are measured through an A-weighting

network are called A-weighted sound levels and are also measured in dB, commonly

written as dBA. It is important to note that many animals respond to sounds much

differently than humans, so that A-weighted sound levels may not correlate well to

sounds that affect or do not affect animals.

Some A-weighted sound levels from typical urbanized or indoor activities or events are

given in Table 36. However, park environments can be much quieter than even the

quietest urban levels (NPS 1995). Also listed in the table is the relative loudness that an

average person would rate the sound sources using quiet urban daytime as a reference

level. For the average human, an increase in the measured sound level of 10 dB is

subjectively perceived as being twice as loud; a 10 dB decrease is perceived as half as

loud, assuming that there is no change in the frequency content of the sound, such as the

presence of tones or unique sounds.

Assuming no change in the frequency content, the sound level change at which the

average human will indicate that the sound is slightly louder or quieter is about 3 dB.

However, the ear is remarkable in its ability to discern very small changes in the sound
NATURAL SOUNDSCAPES

157

environment when new sources are introduced that affect levels in individual frequency

ranges, even when the overall A-weighted sound level does not change.

The ability of a human, free from external distractions, to hear a specific sound in a

particular setting is called audibility. Audibility is a function of the frequency-specific

differences in sound pressure levels between a sound source and the background or

ambient sound environment. While overall A-weighted sound levels give an indication

of relative magnitude of sounds, the A-weighted sound level measure combines into a

single number a large amount of information about the amount of a sound source’s

energy in all frequencies. As a result, A-weighted sound levels are not good measures

for evaluating audibility.

Table 36. Quantitative and qualitative descriptions of typically occurring sounds.

Sound

Level,

dBA

Type of Sound

Relative Loudness

(Human Judgment) of

Different Sound Levels

Subjective

Impression of Sound

110 Nightclub dance floor 128 times as loud Uncomfortably loud

100 Fire engine siren at 100 feet

90 Motorcycle at 25 feet 32 times as loud Very loud

85 D8 Cat dozer at 50 feet

80 Diesel truck, 40 mph at 50 feet 16 times as loud Loud

60-70 Average car, 40 mph at 50 feet

70 Vacuum cleaner at 3 feet 8 times as loud

65 Conversation at 3 feet

60 Background music 4 times as loud

55 Air conditioning unit at 15 feet

50 Quiet residential Twice as loud

45 Bird calls Quiet

40 Lower limit urban daytime ambient Reference loudness

30 Background sound – suburbs at night _ as loud

20 Quiet whisper _ as loud Barely audible

0 Threshold of hearing

To illustrate this point, the A-weighted sound level of a piccolo may be much less than

that of the entire orchestra playing at a concert, but the audience can clearly hear the

piccolo because its sound energy is concentrated in a part of the frequency spectra

different from that of most of the orchestra. Similarly, in the natural environment, the

sound of a distant coyote or a distant snowmobile can be heard and identified by a

listener even though the overall A-weighted sound level may or may not increase during

either type of event.

Sound levels also vary with time, and that variability helps both to define soundscapes

and determine impacts. Average conditions are often represented by the median A-
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weighted sound level, or the sound level exceeded 50% of the time, also called the L50 .

Background sound levels, in the presence of intrusions from other sources, are often

described by the A-weighted sound level exceeded 90% of the time (the L90). Finally, a

commonly used measure for assessing impacts on humans from time-varying noise is the

A-weighted equivalent sound level (the Leq), more properly called the “average sound

level.” Leq is a computed or measured constant level for a given time period that contains

as much sound energy over that time as the actual varying sound level. The averaging

gives more weight to loud events than to quiet events of equal duration. A one-hour

period is commonly used for motor vehicle noise.

Natural and Human-Generated Winter Sound Sources

The existing winter sound environment in each park is a combination of natural and

human-generated sounds. Some significant natural sound sources that are present in

other seasons are not present during winter months in either GTNP or YNP. These

sounds include the rustling of leaves of deciduous trees, birds, insects and animals, and

waterfall and stream sounds. In the winter months, water flow in streams and rivers is

lower than during the spring and summer, and ice covering the streams reduces emitted

sound levels. Generally, winter background natural sounds are limited to wind, windrustled coniferous trees, muffled streams, waterfalls, and animals. Because of the

differences in natural sources, background sound levels in wilderness or national park

areas have been measured as lower during the winter than during the other seasons

(Gdula 1998; Foch 1999).

Human-generated intrusions include snowmobiles and snowcoaches that travel along

designated groomed and ungroomed routes in both YNP and GTNP, as well as wingless

snowplanes that are used mostly by ice fishers on Jackson Lake in GTNP. Humangenerated intrusions also include wheeled-vehicles on plowed roads in GTNP and the

Parkway, such as passenger vehicles that are often pulling snowmobile trailers, and

occasional plow and supply trucks. A limited number of diesel buses also travel to Flagg

Ranch for snowcoach tours into YNP. Other man-made intrusions are the more localized

sounds of cross-country skiing, winter camping, lodging and human voices. In addition

aircraft overflights also occur over both parks. These consist of high altitude commercial

overflights, regular traffic at GTNP associated with Jackson Hole Airport, occasional

NPS flights for research or other park purposes, and occasional private or charter flights.

Areas of primary concern for this analysis are those in which mechanized noise from

wheeled or oversnow vehicles on plowed, groomed or ungroomed motorized trails and

routes affects the natural soundscape within the parks. For purposes of this noise

analysis, the existing noise environment is described in terms of the proximity to these

trails and routes.

In areas adjacent to motorized trails, routes and plowed roads, human-generated activity

is high, human encounters with wheeled or oversnow vehicles are the norm, and the

natural soundscape is often obscured by sound from these snowmachines. However,
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159

even in these areas at times when human-generated sound is not present, the natural

sound environment may be very quiet. These areas include areas along snowmobile

routes or campgrounds where snowmobile access is allowed, such as park entrances and

Flagg Ranch.

For areas somewhat removed from the motorized trails, routes, and plowed roads,

human-generated sound is generally present at lower levels and for less time. With

reduced human-generated sound compared to the areas adjacent to the motorized trails,

routes, and plowed roads, the natural soundscape is not as impacted and visitors have

increased opportunities to experience natural soundscapes.

In distant areas that are substantially removed from the influence of plowed roads or

motorized oversnow trails and routes, human-generated sound is rare. Natural

soundscapes remain unimpaired most or all the time in such distant backcountry areas.

Sounds from wheeled or oversnow vehicles are only occasionally audible within the

background sound in such areas, depending upon the proximity of the motorized trails

and routes, local topography, and sound emission levels of these vehicles.

Existing Sound Levels and Oversnow Vehicle Audibility in YNP and GTNP

Four studies were drawn upon to describe the existing natural background and humangenerated sound levels in YNP and GTNP. Three were completed between 1994 and

1996 by Bowlby & Associates, Inc. as part of a study of the Continental Divide

Snowmobile Trail (CDST). They examined the sound levels of wheeled-vehicles,

snowmobiles, and snowplanes in GTNP, along the Parkway road heading up to Flagg

Ranch, and in the southernmost part of YNP. Some short-term samples of background

sound level data also were collected (Bowlby & Associates 1994; Bowlby & Associates

1995; Bowlby & Associates 1996).

The fourth study, by Harris Miller Miller & Hanson Inc. and Bowlby & Associates, Inc.,

was conducted in February and March 2000 for this EIS with two purposes: 1) measuring

background sound levels in YNP and GTNP; and 2) assessing the noise impact (intruding

sounds) of man-made sounds, including snowmobiles, snowcoaches, snowplanes,

automobiles, buses, and aircraft for the alternatives in the EIS (Harris et al. 2000; Bowlby

& Associates 2000). See Appendix J for more explanation of this study. Intruding

sources included motorized vehicles and human activity, while the most prevalent natural

sound source was wind in the trees. Natural sounds include water sounds, such as geyser

eruptions and gurgling, and flowing rivers, and animal sounds such as coyote howls.

Sound level measurements were conducted at four locations in YNP and four sites in

GTNP in the study. The sites were chosen to provide a mix of areas with heavy

oversnow vehicle use and with little such use. While more sites or longer measurement

durations might be desirable, the measurements that were made provided much useful

information.
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Figure 16 shows the percentage of time that oversnow vehicles were audible during the

daytime audibility logging at each site. The audibility results for the monitored sites

cannot be extrapolated to cover more remote parts of the parks. However, the resulting

background levels that were derived from these sites and used in the impact assessment

are valid for similar, remote areas.

Figures 17 through 24 present samples of the measured sound levels at each site. In these

figures, the bars represent the “energy” average of the total sound for each hour at each

site, often referred to as the equivalent sound level, symbolized as Leq (1h). Energy

averaging refers to the fact that louder moments have much more influence on the Leq

(1h) than quieter moments of equal duration.

The other symbols represent the highest sampled level each hour (Lmax), and the levels

that are exceeded, cumulatively, for different percentages of each hour. For example, the

L10 is the level exceeded for a total of 10% of each hour (for example 6 minutes),

regardless of the noise source. If there are no intrusions and the wind condition remains

the same over the hour, all the measures will be close together, such as in Figure 18.

When there are a few intrusions during an hour, all the measures except Lmax, L1 and

perhaps L10 will be close to each other, such as during the daytime hours at the Pacific

Creek Road site (Figure 23) and at the Grand Canyon of the Yellowstone site. If there

are so many intrusions that there is little time without intrusions, the measures will be

spread out for the hour, as is evident Figures 17 and 21 for the Old Faithful site and for

the Flagg Ranch site.

Old Faithful (YNP)

This site is a major destination for snowmobiles and snowcoaches for day trips and

overnight visits. The measurement location was located about 1,000 feet away from both

the hotel and the geyser areas, where most human activity occurs. It was estimated that

oversnow vehicles were audible for 95% of the daytime period at this site, with nighttime

natural ambient levels at about 30 dBA. Most maximum oversnow vehicle noise levels

were between 35 dBA and 45 dBA. Occasional snowmobile pass-bys on a nearby trail

resulted in maximum sound levels up to 70 dBA. The total range of oversnow vehicle

sound levels measured above ambient was 30 dBA to 70 dBA. Other sounds include

human voices, the geyser eruptions, the gurgling of geyser areas, and wind in the trees.

Grand Canyon of the Yellowstone (YNP)

This site is a moderately- to heavily-forested area about 1 mile from Canyon Village.

The measurement site was located on a low-use side trail about 0.5 miles away from the

junction at Canyon Village. (The high percentage of time intrusions were audible during

the audibility logging at this site, about 87%, is judged to be unrepresentative of the longterm sound environment at this site. A snow-grooming machine was present during

much of the logging time, which occurred during the first two hours of the measurement

period. The noise measurement time-history data clearly indicate that significant

intrusions occur less than 50% of the time.) Other sounds include the river and waterfall
EXISTING SOUND LEVELS AND OVERSNOW VEHICLE AUDIBILITY IN YNP AND GTNP

161

and wind in the trees. Natural ambient levels were generally in the range of 21 dBA to

30 dBA. Typically, oversnow vehicle maximum sound levels were between 45 dBA and

52 dBA. The total range of oversnow vehicle sound levels measured above ambient was

25 dBA to 65 dBA.

West Thumb (YNP)

This site is a moderately-forested area near a popular geyser basin at the edge of

Yellowstone Lake, at the junction of frequently traveled roads. The measurement site

was located about 500 feet from the nearest oversnow vehicle trails and about 100 feet

from a boardwalk at the edge of the geyser area. Oversnow vehicles were audible for

57% of the daytime audibility logging period. Other sounds include the geyser eruptions,

the gurgling of geyser areas, and wind in the trees. Natural ambient levels were in the

range of 22 dBA to 30 dBA, with a distinct plateau at 22 dBA that may have been the

noise floor of the instruments used at this site. Typical oversnow vehicle maximum

levels were between 45 dBA and 55 dBA. The total range of oversnow vehicle sound

levels measured above ambient was 23 dBA to 65 dBA.

Pelican Valley (YNP)

This site is an open, lightly-forested area east of Fishing Bridge on the road to the East

Entrance to the Park, with light to moderate snowmobile traffic. The measurement site

was located about 250 feet from the road. Very low background sound levels (that is,

about 0 dBA at night) were measured in this remote area; yet oversnow vehicles were

audible for 44% of the audibility logging period with maximum oversnow vehicle levels

as high as 66 dBA. Typically oversnow vehicle maximum sound levels were between 57

dBA and 65 dBA. At night very low oversnow vehicle levels were measured resulting in

a total range of oversnow vehicle sound levels measured above ambient from 5 dBA to

66 dBA. Other sounds include wind in the trees.

Flagg Ranch (North End of the Parkway)

This site is a moderately- to heavily-forested foreground area that is the staging area for

snowmobile and snowcoach trips into YNP by tour groups and private parties. Overnight

lodging is available. Small groups of snowmobilers also travel into Flagg Ranch along

the Grassy Lake Road snowmobile trail and the CDST. The latter enter GTNP near

Moran and parallel the paved road from Moran to Flagg Ranch. Oversnow vehicles were

audible for 63% of the daytime audibility logging period. Other sounds included cars,

trucks, and buses carrying visitors, staff and supplies to Flagg Ranch, human voices,

wind in the trees, and water noise along the parts of the Flagg Ranch area closest to the

river. Natural ambient levels were 20 dBA to 30 dBA and maximum oversnow vehicle

levels were 47 dBA to 58 dBA.

Colter Bay (GTNP)

On the shore of Jackson Lake near the marina, this fairly sheltered site is heavily-forested

in all directions except to the west where the terrain is open over the frozen lake.
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Snowplanes used by ice fishers are based on a beach area at Colter Bay and travel out

onto the lake in the morning and back to shore in the late afternoon, with occasional

travel to and from shore and around the lake during the rest of the daytime. The

measurement site was shielded from this beach area by a spit of land out into the lake.

Snowmobiles on the lake are also relatively common during the day. Ranger

observations indicate about 20 snowplanes in use per weekday and 30 per weekend day,

with an estimated 30 snowmobiles per day. Snowplanes and snowmobiles were audible

for 44% of the daytime audibility logging period. Other sounds included cars and light

trucks carrying operators, staff, and supplies to Colter Bay, plows in the parking lot,

human voices, and wind in the trees on the shore and across the snow and ice on the lake.

Natural ambient levels were 18 dBA to 30 dBA and oversnow vehicle maximum levels

were 46 dBA to 65 dBA (the 80 dBA maximum level in Figure 22 may have been the

sound of a snowplow).

Pacific Creek Road (GTNP)

This site is an open area along a very lightly used plowed road across from the Oxbow

Bend area of the Snake River northeast of the Jackson Lake Lodge area. The CDST is

over 2 miles away from the measurement site along the road from Moran to Jackson

Lake. Snowmobiles on the CDST were audible for 6% of the daytime logging period,

but just barely so over the natural background sounds. Other sounds included occasional

cars and light trucks on the Pacific Creek Road, and wind in the trees and across the

snow. Natural ambient levels were in the 17 dBA to 22 dBA, and wheeled-vehicles on

Pacific Creek Road produced maximum levels generally at 40 dBA to 60 dBA. The

relatively high levels (maximums above 40 dBA) for a portion of the night were due to

moderate winds.

Taggart Lake Trailhead (GTNP)

This site is an open to lightly-forested area that is a staging area for cross-country skiing

and snowmobiling at the end of the plowed road from Moose in GTNP. Occasional

ranger snowmobiles were audible, but for only 2% of the daytime logging period. Other

sounds included cars and light trucks entering and leaving the parking area, people’s

voices on the ski trails, and wind in the trees and across the snow.

Natural ambient levels were 19 dBA to 25 dBA, while maximum levels from cars,

snowmobiles and people were at 40 dBA to 45 dBA.

0% 20% 40% 60% 80% 100%

Percentage of Time [%]

Taggart Lake Trailhead

Pacific Creek Road

Colter Bay

Flagg Ranch

Pelican Valley

West Thumb

Grand Canyon of the Yellowstone

Old Faithful

46%

6%

63%

44%

57%

87%

95%

2%

Figure 16. Percentage of time snowmachines were audible during daytime

audibility logging.
EXISTING SOUND LEVELS AND OVERSNOW VEHICLE AUDIBILITY IN YNP AND GTNP

163
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EXISTING SOUND LEVELS AND OVERSNOW VEHICLE AUDIBILITY IN YNP AND GTNP

165
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NATURAL BACKGROUND SOUND LEVELS

167

Natural Background Sound Levels

A range in background sound levels comprises the natural soundscape, depending on

wind conditions, location, and other factors during different time periods. For the

purposes of this analysis, two specific background sound level conditions were identified

for assessing impacts over the range of conditions: 1) the “average” condition, which

includes the average effects of wind during the day; and 2) the “quiet” condition, which

represents times when winds are light or calm.

While the sound level measurements were mostly made over 24-hour periods, the

existing background sound levels occurring during the daytime hours were analyzed

because none of the alternatives envision significant amounts of outdoor human activity

at night. The daytime hours from 8:00 A.M. to 6:00 P.M. were selected and their hourly

statistical sound level data were used to derive the background sound levels used in the

subsequent analysis. At two of the sites, Old Faithful and West Thumb, intruding

sources were heard or expected to be heard for such high percentages of the time, that the

data acquired at those sites were not used to characterize the daytime background sound

conditions.

As noted earlier, average conditions are often represented by the sound level exceeded

50% of the time, also called the L50 . However, because much of the measured sound

level data included some intruding sounds for part of the time, there was concern that the

measured L50 might not represent the true natural L50. Therefore, it was determined that

the A-weighted sound level exceeded 90% of the time (the L90) in each hour would be a

reasonable approximation of what the L50 would have been without intruding sounds.

For nearly all measurements, the L90 and L50 values were within 2 dBA to 4 dBA, despite

the inclusion of the intrusions in the measurements.

Determining the L90 values to use for the average and quiet background conditions was

completed as follows. First, those sites and hours where intrusions were expected to

occur less than about half the time were selected from all the measured hours. The

selection was based on an examination of the data collected at each site and on the

observations and audibility logging conducted during the site visits. The L90 values for

those selected hours for all the sites were then grouped together to form an L90 data set.

These measured hourly L90 values appeared to fall into two categories: 1) sites in mostly

open or lightly forested areas, and 2) sites in moderately forested to heavily forested

areas. The background sound levels in the open areas were slightly lower than those in

the forested areas, the difference due to the sound of wind in the trees. The L90 data set

was thus divided into two groups: open and forested.

The median L90 in each of the two L90 data sets was chosen to represent the average

background sound level condition for each terrain type. The L90 value exceeded by 90%

of the L90 values in each data set was chosen to represent the “quiet” background sound

level condition for each terrain type.
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Data from the Colter Bay, Flagg Ranch, and Grand Canyon of the Yellowstone sites were

used to characterize all forested areas, while data from the Pelican Valley, Taggart Lake,

and Pacific Creek sites were used to characterize open areas in the parks.

The average background sound level in the open areas was 20 dBA; in the forested areas

it was 22 dBA. The quiet background sound level in the open areas was 15 dBA. In the

forested areas, the quiet background sound level was 18 dBA. These levels were used in

the audibility impact analysis in Chapter IV and are summarized below in Table 37.

Table 37. Natural background sound levels by type of site.

Background Sound Level, dBA

Type of Site

Average Condition Quiet Condition

Mostly open or lightly forested 20 15

Moderately or heavily forested 22 18

Cultural Resources

Archeology

American Indians first inhabited the GYA nearly 11,000 years ago. Although more than

a dozen tribes lived in the region during both prehistoric and historic times, the tribes

whose traditional territory falls within the GYA include the Blackfeet, Crow, Nez Perce,

Northern Arapahoe, Northern Cheyenne, Confederated Salish and Kootenai, ShoshoneBannock, and the Shoshone-Eastern Band.

Known prehistoric resources in the GYA provide evidence of hunting, fishing, plant

gathering, and the quarrying of obsidian for tool making. Prehistoric resources range

f r o m l i t hi cs c a t t e r s an d de b i t a ge( at yp eo f si t e or ar t i f a c tc ha r a c t e r i z e d byt h e r e m a i ns of 

a nyp h a s e of st o net o olp r od uc t i o n) tos t r a t i f i e d l a y e r sw i t hh e a r t h s a ndr o a s t i n g pi t s. 

Lithic scatters and debitage constitute the bulk of the evidence of prehistoric use of the

region. Prehistoric resources include:

• Flaked and ground stone tools, such as projectile points, knives, scrapers, milling slabs, and

handstones;

• Obsidian flakes, the refuse of stone tool making;

• Fire-cracked rocks; and,

• Darkened soil middens (refuse heaps) stained by ashes from campfires and organic

remains.

Sites with identifiable features such as trails, rock shelters, stone circles, tipi rings,

burials, or wickiups (simple huts) are less common. Collectively the prehistoric

resources represent thousands of years of human use and document the gradual

adaptation of American Indians to the region’s resources.
CULTURAL RESOURCES

169

Historic archeological sites in the GYA include remnants of American Indian cultures, as

well as Euro-American, the latter including early hunters, miners, and ranchers, the U.S.

military, and the parks’ administration. Euro-American archeological sites include

remains of transportation routes and farming, ranching, and mining operations such as

buildings, pastures, cultivated fields, and irrigation ditches.

There are hundreds of known prehistoric and historic archeological sites within the

boundaries of YNP and GTNP. Obsidian Cliff, a prehistoric site in YNP, is a national

historic landmark. None of the other prehistoric or historic archeological sites are listed

in the National Register of Historic Places, although many are considered to be eligible

for listing.

Buildings and Structures

In 1872 Congress established Yellowstone National Park, the nation’s first national park.

The U.S. Army administered YNP from 1886 to 1916, when the NPS was founded.

Many of the facilities presently in use in the park were designed and built by

concessioners around the turn-of-the-century, by the army before 1916, or by the NPS

during the first two decades of its administration. They embody the rustic style of park

architecture popular before the 1940s. Stonework, massive timbers, and decorative

woodwork are characteristic of the rustic style of park architecture, which strove to make

structures more compatible with their natural settings. Examples of such rustic

architecture include the Old Faithful Inn and the museum at the Norris Geyser Basin.

Five of the buildings and structures in YNP are designated national historic landmarks,

and another eight are listed in the National Register of Historic Places. Table 38 contains

a list of YNP historic resources.

Table 38. Historic resources of YNP — National Historic Landmarks (NHL) or

listed in the National Register — of Historic Places (NHRP).

Historic Resource Status

Fishing Bridge Museum NHL

Lake Fish Hatchery Historic District NRHP

Lake Hotel NRHP

Lamar Buffalo Ranch NRHP

Madison Bridge Museum NHL

Norris Museum NHL

Norris Museum/Norris Comfort Station NRHP

Northeast Entrance Station NHL

Obsidian Cliff Kiosk NRHP

Old Faithful Historic District NRHP

Old Faithful Inn NHL

Roosevelt Lodge Historic District NRHP

Yellowstone Main Post Office NRHP
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In addition to the above, the YNP road system, which includes the Grand Loop Road and

five entrance roads, recently was nominated for inclusion in the National Register.

GTNP was established in 1929 and enlarged in 1950. In GTNP, where ranching and

tourism preceded the establishment of the national park, the remaining rustic and/or

historic buildings and structures are associated with pioneer ranching, dude ranching,

private estates, and early administration by the Forest Service and the NPS. Though none

of the park’s buildings and structures are designated national historic landmarks, many

are listed in the National Register of Historic Places (Table 39).

Table 39. Historic resources of GTNP listed in

the National Register of Historic Places.

4 – Lazy F Dude Ranch Jenny Lake Ranger Station Historic District

AMK Ranch Kimmel Kabins

Aspen Ridge Ranch Leigh Lake Ranger Patrol Cabin

Bar B C Dude Ranch Menor’s Ferry

Brinkerhoff Moose Entrance Kiosk

Cascade Canyon Patrol Cabin Moran Bay Patrol Cabin

Chapel of the Transfiguration Morman Row Historic District

Cunningham Cabin Murie Residence

Double Diamond Ranch Dining Room Old Administrative Area Historic District

Geraldine Lucas Homestead Rams Horn Dude Ranch Lodge

Highlands Ranch Snake River Land Company Buffalo Dormitory

Hunter Hereford Ranch String Lake Comfort Station

Jackson Lake Ranger Station White Grass Dude Ranch

Jenny Lake Boat Concessions Building White Grass Ranger Historic District

Jenny Lake CCC Camp

Authorized in 1972, the Parkway, an 82-mile corridor that links West Thumb in YNP

with the North Entrance of GTNP, commemorates John D. Rockefeller Jr.’s role in

helping to establish national parks throughout the nation, including GTNP. There are no

known historic buildings and structures in either the Parkway or its general vicinity that

are either listed in or eligible to be listed in the National Register of Historic Places.

Flagg Ranch, located on the Parkway, was determined ineligible for listing in the

National Register by the NPS in consultation with the Wyoming State Historic

Preservation Office.

Ethnographic Resources

Ethnographic resources consist of features of the landscape that are linked by members of

a contemporary community to their traditional ways of life. As more specifically defined

by the NPS, ethnographic resources are any “. . . site, structure, object, landscape, or

natural resource feature assigned traditional, legendary, religious, subsistence, or other

significance in the cultural system of a group traditionally associated with it” (Director’s

Order #28: Cultural Resource Management: 181 1998). Recently an ethnographic
CULTURAL RESOURCES

171

overview of YNP, entitled Restoring a Presence: A Documentary Overview of Native

Americans and Yellowstone National Park, was completed. Ethnographic overviews or

assessments have yet to be completed for GTNP and the Parkway.

The overview of YNP, however, demonstrates that “[e]thnographically . . . th[e]

northwestern corner of present-day Wyoming is . . . especially complex and unique . . .

[f]or the Yellowstone Plateau is the convergence point for three out of North America’s

nine aboriginal culture areas . . . .” — the Plateau, Plains, and Great Basin Indian peoples

(Nabokov and Loendorf 1999). The identity of the contemporary Indians associated with

these culture areas revolves around land and spirit. Although not all Indians share

identical cultural traits, land is the matrix of Indian life and spirit. The essence of life is

related to coming from the earth and living with the animal, plant, and other resources of

the land, both material and spiritual. Tribal members today can easily identify resources

and features of YNP that intimately link their culture to the region, including the

Obsidian and Sheepeater Cliffs; and geographic features such as Yellowstone Lake,

water courses, hot springs, and geysers. Similar examples may be present in GTNP and

in the Parkway.

Throughout the planning process, NPS consulted with the eight contemporary American

Indian tribes traditionally affiliated with the GYA—the Blackfeet, Crow, Nez Perce,

Northern Arapahoe, Northern Cheyenne, Confederated Salish and Kootenai, ShoshoneBannock, and the Shoshone-Eastern Band. In addition to the eight affiliated tribes,

representatives of other contemporary American Indian tribes with a cultural interest in

the region were invited to participate in a general tribal consultation meeting at YNP on

May 20, 1999. The Winter Use Plan/EIS was among the projects discussed at this

meeting. Tribes represented were the Assiniboine and Sioux, Cheyenne River Sioux,

Crow Creek Sioux, Flandreau Santee Sioux, Gros Ventre and Assiniboine, Kiowa Tribe

of Oklahoma, Lower Brule Sioux, Oglala Sioux, Rosebud Sioux, Sisseton-Wahpeton

Sioux, Spirit Lake Sioux, Standing Rock Sioux, and the Yankton Sioux. Consultation

with representatives of the affiliated tribes to ensure that their interests and concerns are

adequately incorporated will continue as actions within this Plan progress.

Cultural Landscapes

According to the park service’s Cultural Resource Management Guideline (NPS-28), a

cultural landscape is:

“ . . . a reflection of human adaptation and use of natural resources and

is often expressed in the way land is organized and divided, patterns of

settlement, land use, systems of circulation, and the types of structures

that are built. The character of a cultural landscape is defined both by

physical materials, such as roads, buildings, walls, and vegetation, and

by use reflecting cultural values and traditions.”

Thus, cultural landscapes are the result of the long interaction between man and the land.

They are shaped through time by historical land use and management practices and
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natural disasters such as fires, floods, and earthquakes, as well as politics and property

laws, levels of technology, and economic conditions. Cultural landscapes provide a

living record of an area’s past.

Examples of four general cultural landscape types are found in the GYA:

• Ethnographic Landscapes—Ethnographic landscapes contain natural and cultural resources

that associated people consider heritage resources.

• Historic Sites—Landscapes that are significant for their association with historic events,

activities, or people are considered historical sites.

• Historic Vernacular Landscapes—Landscapes that evolved through use by the people

whose activities or occupancy shaped them are historic vernacular landscapes.

• Historic Designed Landscapes—Landscapes that were consciously designed or laid out

according to design principles or a recognized style or tradition are historic designed

landscapes.

Most of the potential cultural landscapes in the GYA have been formally inventoried or

evaluated for national register eligibility. One landscape, Mormon Row, is on the NRHP

as a rural historic district.

Visitor Access and Circulation

Regional Access

Yellowstone National Park

YNP is located in the northwestern corner of Wyoming, with portions extending into

southwestern Montana and southeastern Idaho. The park is within Teton and Park

Counties in Wyoming, Park and Gallatin Counties in Montana, and Fremont County in

Idaho.

The Interstate Highway system provides access to and through the GYA. Interstate 90

passes through the northern part of the region, serving east-west travel. Interstate 15

serves north-south travel in the western part of the region. Interstates 25 and 80 border

the region on the east and south, and serve as the primary access routes to the area. This

network of roads is fundamentally important to nearly all resource and tourism-related

activities.

Five gateway communities and park entrances serve as local access to the park:

• U.S. Highway 89 through Gardiner, Montana serves the North Entrance, 54 miles south of

Livingston, Montana.

• The Northeast Entrance provides direct park access from Silver Gate, Cooke City, Red

Lodge, and Billings, Montana via U.S. Highway 212.

• The East Entrance connects the park to Cody, Wyoming by U.S. Highway 16, 53 miles east

of the park.

• The Parkway (U.S. Highway 89/287) provides access from the south.

• U.S. Highways 20 and 287 serve access to the West Entrance, through West Yellowstone.
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173

Grand Teton and the Parkway

GTNP is located in west central Wyoming, immediately south of YNP and the Parkway.

It is bounded on the south by the National Elk Refuge. The Parkway provides access

between YNP and GTNP. The Parkway is open year-round between the northern

boundary of GTNP and Flagg Ranch. Flagg Ranch is the major visitor destination in the

Parkway and serves as the winter use staging area for oversnow access to YNP. Regional

access to the Parkway is provided via U.S. Highway 287 from the Moran Entrance to

GTNP on the east, and U.S. Highway 89 on the south from Jackson, Wyoming through

GTNP. GTNP administers the Parkway.

As with YNP, the Interstate Highway system provides regional access to and through

GTNP. Interstate 15 on the western edge of the region provides access to the park from

Idaho Falls, Pocatello, and Boise, Idaho. On the north, Interstate 90 provides direct

access through YNP and the Parkway for Butte, Bozeman, and Billings, Montana during

summer months. Either Interstate 15 or 90 provides winter access to these regional cities.

Interstates 90 and 25 provide regional access from the eastern cities of Sheridan, Casper,

and Cheyenne, Wyoming. Interstate 80 serves as a major east-west connection for

visitors entering the park from the south.

The primary gateway community for GTNP is Jackson, Wyoming, located about 3 miles

south of the park boundary. Moran, Wyoming, on the east edge of the park, is a smaller

gateway community with less reliance on park tourism to support the local economy.

U.S. Highway 89 from the south and U.S. Highway 26/287 from the east provide local

park access from these communities. Dubois, Wyoming, about 50 miles east of Moran

along U.S. Highway 26/28, is a full-service community through which all travel from the

east must proceed, and through which people can access YNP, GTNP, and the Parkway

as an alternative to traveling through Jackson. The northern access route, U.S. Highway

89/287, is closed in the winter to wheeled-vehicles north of Flagg Ranch through YNP.

Park Roadways and Motorized Trails

Yellowstone National Park

YNP roads are maintained for many purposes including touring and sightseeing,

accessing trailheads, and park management. During the winter, all park roads are closed

to wheeled vehicular traffic with the exception of Highway 191, which provides access

between West Yellowstone and I-90 near Bozeman, Montana, and the road from

Mammoth to Tower and Tower to the Northeast Entrance (Cooke City). These two roads

provide the only regional access through the park during the winter. Oversnow vehicular

travel is allowed on the remaining park road segments. One segment, however, is closed

to all winter travel due to avalanche danger between Washburn Overlook and TowerRoosevelt. Where oversnow vehicular travel is allowed, the roads are groomed.

Grooming begins when there is adequate snow cover, and is accomplished using a

tracked vehicle equipped with a blade on the front and a packer wheel and drag at the

rear. The road segments from the West Entrance to Old Faithful are groomed every

night. Most other sections are groomed every other night.
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Visitors reach most park features via snowmobiles, snowcoaches, and cross-country skis.

Staging areas, or points of access, for oversnow routes into the park are an important

component of the winter visitor experience. They typically include a parking area with

appropriate signing and may have restrooms, a warming hut, and snowmobile rental

facilities. Snowcoach routes offered by concessioners provide access to the park from

some staging areas. The staging areas for trips into YNP are near Mammoth Hot Springs

in the north, at Pahaska Teepee in the Shoshone National Forest near the East Entrance,

at a parking area just north of Flagg Ranch near the South Entrance, and in West

Yellowstone near the West Entrance. These staging areas become congested during peak

days because of small or undefined parking and unloading areas. Many difficulties exist

in serving winter visitors, including a shortage of all-weather facilities and the dangers of

exposure to subzero temperatures.

Park operations and maintenance personnel groom 184.6 miles of park roads, and plow

56 miles. About 14.2 miles are closed to winter travel. The July 1994 study: Alternative

Transportation Modes Feasibility Study, Volume III, Yellowstone National Park, defines

the internal park roadway system by fourteen roadway segments. These segments are

described below. The descriptions provide mileage and indicate if the segment is

plowed, groomed, or closed during the winter season. About 37 miles of groomed

nonmotorized trails are provided in the park. These trails are near Mammoth, Canyon,

Tower, Virginia Cascades, Blacktail Plateau, East Entrance, and Old Faithful.

Segment 1: Canyon Village to Norris Junction (13.1 miles). Segment 1 is groomed for

oversnow winter travel. Norris Geyser Basin at Norris Junction is the largest and

thermally hottest basin in the park. Virginia Cascades, east of Norris, is available for

cross-country skiing.

Segment 2: Mammoth Hot Springs to Norris Junction (22.6 miles). Segment 2 is

groomed for oversnow winter travel from Mammoth Terraces to Norris (about 21 miles).

This segment follows the Gardner River and Obsidian Creek drainage basins through a

number of significant natural and cultural features. Mammoth Hot Springs is the site of

park headquarters and offers a full range of visitor services and access to outstanding

thermal features. Bison and elk can be viewed in the Norris Geyser basin. The warm

waters of the Gibbon River stay open all year, attracting elk and bison during the winter.

A warming hut exists at Indian Creek. The Terrace Loop Drive and the Indian Creek

area are available for skiing.

Segment 3: Mammoth Hot Springs to North Entrance (4.8 miles). Segment 3 is

plowed. This segment parallels the Gardner River, passes under a historic stone arch and

ends at the North Entrance. The North Entrance is the second most heavily used winter

use entrance, and the third most heavily used park entrance year round. Just beyond the

park boundary at the confluence of the Gardner and Yellowstone Rivers is the gateway

town of Gardiner, Montana. A substantial number of elk, deer, moose, pronghorn

antelope, and bighorn sheep inhabit the area.
VISITOR ACCESS AND CIRCULATION

175

Segment 4: Mammoth Hot Springs to Tower Junction (18.5 miles). Segment 4 is

plowed. This segment crosses the Gardner River, follows Lava Creek for a short

distance, and then rises up and over the Blacktail Deer Plateau. It generally follows the

broad course of the Yellowstone River Valley. Extensive bison and elk viewing are

available along this segment. Blacktail Road is available for skiing.

Segment 5: Tower Junction to Northeast Entrance (32.7 miles). Segment 5 is

plowed. This segment closely follows the course of the Lamar River and Soda Butte

Creek. The towns of Silver Gate and Cooke City, Montana, just beyond the Northeast

Entrance, offer a full range of visitor services. The Lamar Valley, which is 15 miles long

and 3 to 5 miles wide, is one of the more remote areas of the park. It supports abundant

wildlife populations, especially bison and elk.

Segment 6: Tower Junction to Canyon Village (18.2 miles). About 14.2 miles of this

segment south of Tower Junction to Washburn Hot Springs Overlook are closed to winter

travel. The remaining segment, about 4 miles, is groomed from Washburn Hot Springs

Overlook to Canyon Village. The segment from Tower Junction, by Tower Falls, to the

top of the Chittenden Road is available for skiing. Segment 6 has a diverse population of

animals, including moose and deer, and a wide variety of vegetation, including species

characteristic of alpine tundra.

Segment 7: Canyon Village to Fishing Bridge (15.7 miles). Segment 7 is groomed.

This segment closely follows the Yellowstone River from Canyon Village through the

Hayden Valley. The road ends at Fishing Bridge, with access to the Lake developed area

and the East Entrance road. Except for parking associated with the thermal features,

there are no developed features along segment 7. Abundant wildlife, especially bison, is

easily visible from the roadway. The Sulphur Cauldron and Mud Volcano thermal areas,

about 10 miles south of Canyon Village, are especially active thermal areas. There is a

gasoline station and a warming hut at Canyon Village. The north and south rim drives

are groomed.

Segment 8: Fishing Bridge to East Entrance (25.4 miles). Segment 8 is groomed.

This segment leaves Fishing Bridge, crosses the Pelican Valley, follows the northern

edge of Yellowstone Lake, crosses Sylvan Pass in the Absaroka Range, and descends

along the eastern edge of the Yellowstone Plateau to the eastern park border. The

trailhead is 2 miles east of the boundary at Pahaska Teepee. The road provides access to

Cody, Wyoming, 53 miles to the east. A gasoline station and warming hut are available

at Fishing Bridge. A ski trail is groomed parallel with the East Entrance road for several

miles west of Pahaska Teepee.

Segment 9: Fishing Bridge to West Thumb (20 miles). Segment 9 is groomed. This

segment traces a course along the western shore of Yellowstone Lake. A warming hut

exists at West Thumb. Lodgepole pine stands are dense in this area and several tributary
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streams provide excellent moose habitat. Elk and bison are often seen along the

roadway, which provides excellent views and access to Yellowstone Lake.

Segment 10: West Thumb to South Entrance (22 miles). Segment 10 is groomed.

This segment begins at the West Thumb Geyser Basin, a thermal area on the shore of

Yellowstone Lake. At Lewis Lake, about 10 miles from West Thumb, the road follows

the eastern shore, then passes Lewis Falls, parallels the Lewis River, and traverses the

Lewis River canyon. A short distance before the South Entrance, the road begins to

follow the Snake River drainage, exits Yellowstone, and becomes the John D.

Rockefeller, Jr., Memorial Parkway. A ranger station is located at the South Entrance.

Two miles south of the South Entrance is Flagg Ranch, an access point with food,

gasoline, and a ranger station.

Segment 11: West Thumb to Old Faithful (17.8 miles). Segment 11 is groomed. This

segment climbs to the west from West Thumb to the Craig Pass crossing of the

Continental Divide at over 8,000 feet. A warming hut exists at West Thumb. Elk and

bison are frequently seen wintering near the West Thumb and Old Faithful thermal areas.

Kepler Cascades is visible along the southern edge of the roadway shortly before

reaching Old Faithful. The Lone Star Geyser area is available for skiing.

Segment 12: Old Faithful to Madison Junction (16.6 miles). Segment 12 is groomed.

This segment follows the banks of the Firehole. More than 300 geysers and 10,000 other

thermal features are found along or near this road segment—more than the combined

total in all other locations around the world. A gasoline station and two warming huts are

available at Old Faithful. Thermal areas attract large mammals, especially in winter

when elk and bison feed near the hot springs. Several ski routes are available in the Old

Faithful area. The Fountain Flats road is also available for skiing.

Segment 13: Madison Junction to West Entrance (13.7 miles). Segment 13 is

groomed. A warming hut exists at Madison. This segment begins at the junction of the

Firehole and Gibbon Rivers and follows the Madison to the West Entrance. The first half

of the road travels through Madison Canyon with National Park Mountain and Mounts

Haynes and Jackson flanking the road. The second half offers access to the river via

numerous informal pullouts and drives. Winter visitors are rewarded with frequent

animal concentrations attracted by nearby thermal areas. The Barns road is a popular

area available for skiing.

Segment 14: Madison Junction to Norris Geyser Basin (13.7 miles). Segment 14 is

groomed. This segment passes through scenic mountain meadows, following the Gibbon

River and passing through Gibbon Canyon en route to the river’s confluence with the

Madison River. A portion of the road follows the rim of the Yellowstone Caldera. The

road passes cliff formations and Gibbon Falls, which tumbles over the rim of the caldera.

Thermal areas attract animals. The falls and Gibbon Geyser Basin are principal visitor

attractions.
VISITOR ACCESS AND CIRCULATION

177

Grand Teton and the Parkway.

The Parkway encompasses 24,000 acres between YNP and GTNP, and is also a roadway

through GTNP. It provides access to Flagg Ranch, which serves as a principal winter use

staging area. The roadway itself is about 7.5 miles through the Parkway, between the

South Entrance to YNP and the northern edge of GTNP. The road is groomed between

Flagg Ranch and YNP and plowed south of Flagg Ranch to GTNP. The CDST (see

Background and History, Chapter I) parallels the road between the eastern boundary of

GTNP and Flagg Ranch, and is accessed from trail systems on the adjacent Shoshone and

Bridger-Teton National Forests out of Jackson and Dubois. Grassy Lake Road,

beginning at Flagg Ranch and continuing west outside the Parkway boundary into

Targhee National Forest is groomed in the winter for oversnow travel.

The roadway system within GTNP is comprised of regional through highways and local

park roads providing access to visitor destination areas within the park. The two through

highways in the park are U.S. Highways 89 and 287—both are plowed during the winter

for wheeled-vehicle access. Highway 89 extends south from Moran Junction to the

South Entrance of GTNP, providing access from Jackson, Wyoming. This highway also

provides the only access to Jackson Hole Airport, located south of Moose Junction within

the park. Between Moose Junction and Moran Junction, this roadway follows the Snake

River, a sensitive resource area for wintering wildlife.

Highway 287 traverses the park from the eastern park boundary, near the Moran Entrance

Station, to the Parkway. Colter Bay, about 9 miles northwest of Moran, is the only

visitor destination area along the roadway segment within the park. The CDST parallels

the roadway from Moran to the northern edge of the park and further north to Flagg

Ranch. The CDST is a groomed snowmobile trail constructed during the winter. In

many areas the CDST occupies the roadway right-of-way and constricts the roadway to

one lane. Access to Signal Mountain is provided along a short portion of Teton Park

Road between Signal Mountain and Jackson Lake Junction. This segment of Teton Park

Road is plowed for wheeled access in the winter.

Teton Park Road traverses the eastern edge of the Teton Range between Moose Junction

and Jackson Lake Junction. This roadway is plowed during the winter for a short length

at both ends to provide winter use access to Taggart Lake Trailhead on the south and

Signal Mountain on the north. The remaining portions of the road, including the Jenny

Lake Loop and a short access route to Spalding Bay, are available for oversnow travel.

While not a transportation facility, Jackson Lake provides motorized recreational

opportunities during the winter for snowmobiles and snowplanes. This is believed to be

one of few locations in the country where snowplanes operate. Snowplanes are small,

enclosed crafts, propelled across ice and snow by a rear-mounted propeller. The crafts

are supported and steered by skis. Snowplane access to the lake is provided at Signal

Mountain and Colter Bay.
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Moose-Wilson Road, a narrow, lightly traveled roadway without shoulders, extends

southwest from the Moose Visitor Center to the park boundary and on to the towns of

Teton Village and Wilson. In the winter the roadway is plowed and open to wheeledvehicles from both ends: from the southwest boundary to the Granite Canyon Trailhead,

and from the corner near the Moose Visitor Center to the JY Ranch entrance. Oversnow

motorized travel is permitted between the road segments. The roadway provides access

to several private inholdings along the road.

Other, less traveled, roadway segments in the park include:

• The segment along the Gros Ventre River between the Gros Ventre Junction and Kelly;

• North from Kelly to Triangle X Ranch with two access points to Bridger Teton National

Forest between Kelly and Mailbox Corner;

• Antelope Flat Road between Highway 89, north of Moose Junction, east to Mailbox

Corner.

• Plowed portions of these roadway segments include:

• The section along the Gros Ventre River between Gros Ventre Junction and Kelly;

• North of Kelly to Mailbox Corner;

• The two Bridger Teton National Forest access roadway segments (a short portion of the

northern access road is not plowed west of the forest);

• A short segment of Antelope Flat Road at the intersection with Highway 89.

The remaining roadway segments are open to oversnow travel with the exception of the

unplowed portion of Antelope Flat Road to Mailbox Corner.

Park Facilities and Winter Destination Areas

Park facilities and winter destination areas are described below within the context of each

park unit by available lodging, parking, and other winter use amenities such as the

provision of warming huts, cross-country ski and snowshoe trail access, and winter use

fueling facilities. It should be noted that there are a number of accommodations in the

parks that are not available during winter because of infrastructure vulnerability to

freezing temperatures.

Lodging

Winter lodging facilities in YNP provide a total of 256 rooms with 413 beds. Table 40

itemizes each lodging facility in the park and identifies the number of winter rooms and

beds.

Table 40. Winter lodging facilities and numbers of rooms.

Facility Bed Total Rooms

Mammoth Hot Springs Hotel and Cabins 191 132

Old Faithful Snow Lodge and Cabins 222 124

Total 413 256

Source: TW Recreational Services, November 1992 Existing Concession Services and Facilities Report, Yellowstone

National Park, 1998 (Snow Lodge information updated in 2000).
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179

In addition to the above lodging facilities, Yellowstone Expedition operates 10 yurts plus

a community yurt and mess yurt near Canyon Village. The yurt camp logged 418 user

days during the winter of 1998-99. In addition, the park issued 118 backcountry camping

permits during the same time period.

For GTNP and the Parkway, Flagg Ranch and Triangle X are permitted by NPS to

provide overnight accommodations during the winter. Colter Bay and Jackson Lake

lodge facilities are closed for winter use. However, the area is open during winter

months to provide snowplane, snowmobile, and cross-country skiing and snowshoeing

opportunities at Jackson Lake and in surrounding areas.

Parking

There is an area equivalent to about 960 parking spaces located at selected winter use

destination areas in YNP. This includes the space needed to store snow at each area

(about 50%). These capacities are used to estimate visitor access and circulation impacts

of the EIS alternatives. Table 41 presents the parking capacities at relevant winter use

destination areas.

Table 41. Average winter parking capacity in YNP destination areas.

Area Capacity*

Mammoth Hot Springs 480

Tower-Roosevelt 180

Old Faithful 150

Madison Junction†30

Norris†120

Total Spaces Available for Winter Visitor Use

(space available for wheeled-vehicle access)

960

†Existing capacity numbers are given for these sites to estimate changes in various alternatives

Source: Inventory by BRW, Inc., August 1992.

*Considering snow storage consumption, estimated by NPS, May 1999.

In GTNP and the Parkway, the primary facility for winter use parking and staging is

Flagg Ranch. Cross-country skiing and other nonmotorized winter users represent a

small percentage of users in the area. The pattern of use is similar to private snowmobile

users in that they arrive in private vehicles, arrive at variable times of the day and stay

irregular lengths of time. Public winter parking at Flagg Ranch is available in a new

parking facility with more than 300 spaces for autos. Fifty 60-foot long spaces are

available on the Parkway. Some parking is also provided along the straight section of the

main entrance road.

About 225 winter parking spaces are available at Colter Bay considering the need for

snow storage in an average year.
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Other Winter Services and Facilities

Yellowstone National Park

Warming huts in YNP are located at Mammoth, Canyon Village, Indian Creek, Fishing

Bridge, Madison, Old Faithful, and West Thumb. A new warming hut has been approved

and is planned for Norris. The Canyon Village, Old Faithful and Madison warming huts

are scheduled for replacement. Warming huts at Mammoth, Madison, and Canyon

Village locations are staffed by concession personnel who operate small snack bars and

maintain vending machines. NPS interpreters, who answer questions and provide

information and various forms of assistance to visitors, also staff some of the huts.

Groomed nonmotorized trails are provided near Mammoth, Canyon Village, TowerRoosevelt, Virginia Cascades, Blacktail Plateau, East Entrance, and Old Faithful. Winter

use fueling facilities are available at Old Faithful, Fishing Bridge, and Canyon Village.

Snowcoach tours in YNP operate from Mammoth Hot Springs, Old Faithful, West

Yellowstone and Flagg Ranch (the Parkway). Snowcoaches provide cross-country skiing

tours, snowshoeing tours, and sightseeing tours.

Snowmobile rentals are available at Old Faithful and Mammoth. Thirty machines are

available at Mammoth Hot Springs, and 20 to 30 are available at Old Faithful for selfguided tours. In West Yellowstone there are about 1,400 snowmobiles available for rent

and seven operators are licensed by the park to provide guided snowmobile tours of

YNP. Three additional operators are licensed, and operate out of Pahaska Teepee and

Cody, Wyoming and Tetonia, Idaho. Snowmobile tours are restricted to 11 snowmobiles

each, including guides.

Grand Teton National Park and the Parkway

Flagg Ranch is the major staging area for oversnow travel from the south to YNP.

Primary winter users at Flagg Ranch are commercial snowmobile tour operators, private

snowmobiles, snowcoach tour operators, Flagg Ranch snowmobile renters, and crosscountry skiers. Most facilities at Colter Bay are closed during winter months, but a

plowed area remains open to camping for use by people who snowplane, snowmobile,

ski, and snowshoe on Jackson Lake or in the area. Dornan’s, an inholding in GTNP, is

open year-round and offers dining, a general store, gas, and visitor information in the

winter months. Park headquarters and the Moose Visitor Center, located across the

Snake River just west of Moose Junction, are open in the winter.

In 1998 there were 11 commercial snowmobile tour permits issued at Flagg Ranch. Tour

leaders provide the tour group with a brief instruction and practice before leaving the

area. AMFAC, a YNP permittee, offers tours and transportation from Flagg Ranch.

Snowcoach operators currently load and unload tourists in front of the lodge at Flagg

Ranch. Six to ten snowcoaches, each accommodating eleven people, run daily into YNP.
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The concessioner at Flagg Ranch maintains 80 snowmobiles for rental to lodgers and day

users. The machines are stored in an area about 1,000 square feet adjacent to the existing

gas station.

Colter Bay/Jackson Lake lodge facilities are closed for winter use. However, the area is

open during winter months to provide snowplane, snowmobile, and cross-country

skiing/snowshoe opportunities at Jackson Lake and in surrounding areas. Other

destination and support facilities are available at Moose Visitor Center, with limited

services at Colter Bay. Ski tours are periodically available from Moose and Flagg Ranch.

Currently there are no warming hut or trailside facilities available. Ungroomed ski and

snowshoe trails are available from Taggart Lake Trailhead to Jenny Lake, along Antelope

Flats Road, and near Moose, Death Canyon, Granite Canyon, Two Ocean Lake, Colter

Bay, and Flagg Ranch.

Winter Visitor Use

Yellowstone National Park

Winter activity at YNP is composed primarily of visitors on snowmobiles (62%),

automobiles and bus passengers (29%), snowcoach passengers (9%), and cross-country

skiers (1%). The following table contains visitor counts by activity from 1992 through

2000 winter seasons. The average seasonal visitor count is 128,720 visitors.

Table 42. Winter use activities in YNP.

Winter

Season

Visitors by

Auto

Recreation

Vehicle

Bus

Passengers Skiers† SnowmobilePassengers

Snowcoach

Passengers

Total

Visitors

92/93 36,202 164 378 464 91,196 14,340 142,744

93/94 41,041 308 751 998 87,682 12,743 143,523

94/95 39,329 177 432 684 86,286 12,729 139,637

95/96 33,719 123 280 1,081 75,265 9,071 119,539

96/97 30,432 129 429 485 71,759 10,221 113,455

97/98 35,704 81 305 453 72,834 9,897 119,274

98/99 36,450 90 173 446 76,271 10,779 124,209

99/00 37,872 140 747 351 76,571 11,699 127,380

Total 290,749 1,212 3,495 4,962 637,864 91,479 1,029,761

Percent 28% <1% <1% <1% 62% 9% 100%‡

Average 36,343 152 437 626 79,733 11,435 128,720

Source: NPS visitation records.

†Numbers of skiers reflect the number of visitors that actually skied through the entrance gate. It does not reflect the

number of visitors that access the park via another mode of transportation and then ski in the park interior. Visitor surveys

indicate about 20% of visitors ski in the park (Littlejohn 1996).

‡Total greater than 100% due to rounding.
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The visitor counts for the various entrance stations were tallied to produce Table 43.

This information indicates that the highest visitor traffic is at the West Entrance, followed

by the North Entrance and South Entrance. The East Entrance accounted for 3% of the

visitor traffic in the reported winters. Counts are not kept at the Northeast Entrance in

the winter because there is no through traffic from the east.

Table 43. Winter use visitors in YNP — by entrance station.

Winter North West South East Total

1989-90 24,949 50,730 20,322 3,581 99,582

1990-91 25,935 51,560 22,378 3,666 103,539

1991-92 35,146 55,005 23,411 4,203 117,765

1992-93 40,150 70,844 27,001 4,459 142,454

1993-94 45,290 65,603 28,124 4,506 143,523

1994-95 42,987 66,294 25,893 4,463 139,637

1995-96 37,366 57,380 20,668 4,125 119,539

1996-97 34,902 56,069 19,272 3,212 113,455

1997-98 40,497 54,859 20,486 3,432 119,274

1998-99 41,007 59,928 20,385 2,889 124,209

1999-00 42,903 58,154 22,957 3,366 127,380

Total 411,132 646,426 250,897 41,902 1,350,357

% of total 30% 48% 19% 3% 100%

Source: NPS visitation records.

North Entrance. The North Entrance is the only YNP entrance accessible to wheeledvehicles during the winter season. Oversnow travel begins at Mammoth Terraces, 0.5

miles south of Mammoth Hot Springs. The North Entrance received 30% of the winter

visitors between the 1992-93 and 1999-2000 seasons. Traffic at this point is

predominately wheeled-vehicles with about 89% of visitors arriving by automobile, bus,

or recreational vehicle. Traffic using the highway to Cooke City is not counted as YNP

visitors. The primary attraction accessible from the North Entrance during the winter

season is Mammoth Hot Springs with its associated facilities. There also are several

cross-country ski trailheads located near Tower-Roosevelt. Table 44 lists visitor counts

by mode of transportation by winter season for the North Entrance.
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Table 44. Winter use activities in YNP — North Entrance.

Winter Visitors by

Auto†, ‡

Recreation

Vehicle

Bus

Passengers Skiers* SnowmobilePassengers

Snowcoach

Passengers

Total

Visitors

1992-93 36,202 164 378 5 708 2,693 40,150

1993-94 41,041 308 751 13 528 2,649 45,290

1994-95 39,329 177 432 6 625 2,418 42,987

1995-96 33,719 123 280 11 1,731 1,502 37,366

1996-97 30,432 129 429 21 2,080 1,811 34,902

1997-98 35,704 81 305 10 2,119 2,278 40,497

1998-99 36,450 90 173 17 2,196 2,081 41,007

1999-00 37,872 140 747 21 1,617 2,506 42,903

Total 290,749 1,212 3,495 104 11,604 17,938 325,102

% of total 89% <1% 1% <1% 4% 5% 100%**

Average 36,343 152 436 13 1,451 2,242 40,637

Source: NPS visitation records

†Statistics for automobile visitors reflect visitor use for the entire months of December and March.

‡Visitor surveys indicate that about 25% of all visitors who arrive by automobile also skied in the park (Littlejohn 1996).

*Numbers of skiers reflect the number of visitors that actually skied through the entrance gate. It does not reflect the

number of skiing visitors that access the park via another mode of transportation.

**Total greater than 100% due to rounding.

West Entrance. The West Entrance is the single busiest entrance to YNP. This entrance

received 48% of the winter visitors between the 1992-93 and the 1999-2000 seasons;

90% of the visitors used snowmobiles as their mode of travel. Of the 639,194 visitors

entering YNP on snowmobiles during the winter seasons between December 1992 and

March 2000, 69% (439,798) arrived at the West Entrance. Table 45 includes visitor

counts for the West Entrance by winter season and mode of travel. The West Entrance is

not accessible to wheeled-vehicles, so auto, bus, and recreational vehicle passenger

counts are not shown.
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Table 45. Winter use activities in YNP — West Entrance.

Winter Skiers† Snowmobile

Passengers

Snowcoach

Passengers Total Visitors

1992-93 13 62,590 8,241 70,844

1993-94 6 58,731 6,866 65,603

1994-95 19 59,405 6,870 66,294

1995-96 14 52,455 4,911 57,380

1996-97 21 50,296 5,752 56,069

1997-98 18 49,776 5,065 54,859

1998-99 27 53,980 5,921 59,928

1999-00 21 52,575 5,558 58,154

Total 139 439,798 49,184 489,131

% of total <1% 90% 10% 100%‡

Average 17 55,976 6,148 61,141

Source: NPS

†Numbers of skiers reflect the number of visitors that actually skied through the entrance gate. It does not reflect the

number of skiing visitors that access the park via another mode of transportation. Visitor surveys indicate about 20% of

visitors skied in the park (Littlejohn 1996).

‡Total greater than 100% due to rounding

East Entrance. The East Entrance is located on Highway 14/16, which connects to

Cody Wyoming. Snowmobile riders (90%), followed by cross-country skiers (10%),

primarily use the East Entrance. The East Entrance provided access to YNP for about

3% of the total park visitors during the winter seasons from December 1992 and March

2000 (Table 46). Groomed cross-country ski trails are available at the East Entrance. As

with the West Entrance, there is no wheeled-vehicle access.

Table 46. Winter use activities in YNP — East Entrance.

Winter Skiers† Snowmobile

Passengers

Snowcoach

Passengers Total Visitors

1992-93 375 4,075 9 4,459

1993-94 850 3,647 9 4,506

1994-95 539 3,917 7 4,463

1995-96 957 3,160 8 4,125

1996-97 355 2,857 0 3,212

1997-98 346 3,077 9 3,432

1998-99 263 2,620 6 2,889

1999-00 204 3,105 57 3,366

Total 3,889 26,458 105 30,452

% of total 14% 86% <1% 100%

Average 486 3,307 13 3,869

Source: NPS

†Numbers of skiers reflect the number of visitors that actually skied through the entrance gate. It does not reflect the

number of skiing visitors that access the park via another mode of transportation. Visitor surveys indicate about 20% of

visitors skied in the park (Littlejohn 1996).
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South Entrance. Visitors to YNP who gain access through the South Entrance must first

travel through GTNP. This entrance accounted for almost 18% of the visitors for the

1992-93 through 1999-2000 winter seasons. As with the entrances other than the North

Entrance, snowmobiles were the primary mode of transportation. The South Entrance

had the second highest number of snowcoach passengers and snowmobiles during the

reported winters (Table 47). The South Entrance is not accessible to wheeled-vehicles.

Table 47. Winter use activities in YNP — South Entrance.

Winter Season Skiers† Snowmobile

Passengers

Snowcoach

Passengers Total Visitors

1992-93 62 23,665 3,274 27,001

1993-94 129 24,776 3,219 28,124

1994-95 120 22,339 3,434 25,893

1995-96 99 17,919 2,650 20,668

1996-97 88 16,526 2,658 19,272

1997-98 79 17,862 2,545 20,486

1998-99 139 17,475 2,771 20,385

1999-00 105 19,274 3,578 22,957

Total 821 159,836 24,129 184,786

% of total <1% 87% 13% 100%‡

 Average 103 19,979 3,016 23,118

Source: NPS visitation records

†Numbers of skiers reflect the number of visitors that actually skied through the entrance gate. It does not reflect the

number of skiing visitors that access the park via another mode of transportation. Visitor surveys indicate about 20% of

visitors skied in the park (Littlejohn 1996).

‡Total greater than 100% due to rounding.

The following table contains information on the locations visited by winter users

(Littlejohn 1996). The percentages do not total 100 since respondents could visit more

than one site. The most visited site was Old Faithful (76%), followed by Madison (62%),

Canyon (48%), and Norris (48%).

Table 48. Sites Visited in February 1995.

Yellowstone National Park Sites Visited by Yellowstone National Park Survey Respondents

Mammoth

Hot Springs Norris Madison OldFaithful

West

Thumb

Fishing

Bridge Canyon TowerJunction

43% 48% 62% 76% 41% 34% 48% 22%

Grand Teton National Park Sites Visited by Yellowstone National Park Survey Respondents

Flagg Ranch Jackson

Lake Jenny Lake TaggartLake

Moose Visitor

Center

Signal

Mountain Colter Bay

22% 5% 2% 1% 5% 1% 4%

Source: NPS Yellowstone National Park Visitor Study
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Grand Teton National Park and the Parkway

Unlike YNP, GTNP’s main access routes are plowed during the winter season. The

visitor counts for GTNP tally visitors arriving via wheeled-vehicles. GTNP experienced

a higher number of winter season visitors than YNP. The average visitor count for YNP

for the eight winter seasons of December 1992 through March 2000 is 128,720. GTNP

received an average of 167,694 visitors for the eight winter seasons between December

1992 through March 2000 (Table 49).

Table 49. Winter recreational visits, by year, in GTNP

92/93 93/94 94/95 95/96 96/97 97/98 98/99 99/00 Total

128,159 146,621 156,112 167,120 162,627 176,601 180,367 223,944 1,341,551

Source: NPS visitation records

GTNP visitor counts include visitors using the Parkway. Flagg Ranch, a commercial

operation licensed to provide various visitor services to complement winter use activities,

provides visitor accommodation within the Parkway. The Parkway accommodated

116,489 snowmobile visitors between December 1994 and March 2000, a season average

of 19,414 for the six winters. This represents 77% of the snowmobile traffic for the area

and the highest number of snowmobile visits for the GTNP.

Visitor counts for GTNP also include snowmobiles using the CDST (Table 50). This

user-fee-supported facility provides a 27-mile long, 10-foot to 14-foot wide, groomed

snowmobile trail immediately adjacent to Highways 26/287 and 89/191/287. An

additional 3-mile segment generally follows Teton Park Road from Highway 89/191/287

to Signal Mountain. Speed limits for the CDST are the same as for the adjacent highway

and range from 15 mph to 55 mph. The NPS reduces highway speed limits by 10 mph or

more during the season that the CDST operates.

Table 50. Winter use activities in GTNP.

Winter

Season

The Parkway

Snowmobile

CDST

Snowmobile

GTNP

Snowmobile

GTNP

Snowplane

The

Parkway

Skiing

GTNP

Skiing

Total

Visitors

93/94 2,131 1,623 2,855 6,609

94/95 21,748 1,394 2,788 1,757 1,898 1,619 31,204

95/96 17,619 2,912 3,241 1,734 1,367 1,862 28,735

96/97 19,024 2,779 3,843 1,790 1,440 1,636 30,512

97/98 17,589 2,318 4,051 1,685 1,373 1,577 28,593

98/99 17,110 2,304 3,617 851 1,169 1,298 26,349

99/00 23,399 1,329 2,867 1,091 1,581 5,387†35,654

Total 116,489 13,036 20,407 11,039 10,451 16,234 187,656

Percent 62% 7% 11% 6% 6% 9% 100%‡

Average 19,414 2,172 3,401 1,577 1,493 2,319 26,808

Source: NPS visitation records

†Reason for increase in skier numbers unknown.

‡Total greater than 100% due to rounding.
187

GTNP performed visitor counts at various locations within the park that indicate the

travel patterns for park visitors. Counts were administered at the Moose Entrance, Moran

Entrance, Gros Ventre Junction, US 89 westbound, the Parkway northbound, and MooseWilson Road Counts were tallied monthly from January 1991 to March 2000. The

highest traffic levels were recorded at Gros Ventre Junction with a total of 1,941,322

vehicles during the winters between December 1992 and March 2000. The next highest

counts were recorded at US 89 westbound (377,553), Moran Entrance (193,460), and

Moose Entrance (117,533).

Table 51. Winter recreational visits in and adjacent to GTNP.

GTNP—Moose Entrance

Winter Season 92/93 93/94 94/95 95/96 96/97 97/98 98/99 99/00 Total Visitors

Visits 16,072 17,810 15,776 13,313 13,921 13,166 13,307 14,168 117,533

GTNP—Moran Entrance

Winter Season 92/93 93/94 94/95 95/96 96/97 97/98 98/99 99/00 Total Visitors

Visits 17,359 23,726 27,861 23,765 24,004 23,471 23,733 29,541 193,460

Gros Ventre Junction

Winter Season 92/93 93/94 94/95 95/96 96/97 97/98 98/99 99/00 Total Visitors

Visits 183,733 201,266 206,709 226,597 256,092 282,171 275,409 309,345 1,941,322

US 89 Westbound

Winter Season 92/93 93/94 94/95 95/96 96/97 97/98 98/99 99/00 Total Visitors

Visits 41,369 41,576 49,219 45,907 46,594 48,072 50,371 54,445 377,553

GTNP—The Parkway Southbound

Winter Season 92/93 93/94 94/95 95/96 96/97 97/98 98/99 99/00 Total Visitors

Visits 8,474 7,829 8,911 7,995 7,363 11,200 11,895 21,787 85,454

GTNP—Moose Wilson Road

Winter Season 92/93 93/94 94/95 95/96 96/97 97/98 98/99 99/00* Total Visitors

Visits 0 0 0 5,388 4,625 5,291 6,215 12,455 33,974

Source: NPS visitation records

*Increase in use is attributed to more accurate counting methods.

Visitor Experience

This section describes existing visitor experience relative to three topics:

• Winter visitor profile data and survey results.

• A description of peoples’ values and expectations about winter use based on survey data.

• Measures of visitor experience and satisfaction.

Conclusions are drawn about the most important aspects of visitor experience relating to

the winter plan alternatives and their consequences. Where relevant, specific studies are

cited to support these discussions.

Winter surveys have been conducted to collect information about the people who use the

parks in the winter, and what they expect relative to visitor experience. Most people

surveyed were visiting the parks or surrounding areas, on a snowmobile, at a hotel, or

with an interest group. The states and counties surrounding the parks have completed
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several surveys that pertain to winter use. Although most of the highlighted surveys in

YNP and GTNP have interviewed winter visitors, one survey of summer visitors and a

recently completed telephone survey attempt to quantify opinions about winter use from

regional and national audiences.

Winter Visitor Profile

Numbers of Winter Visitors

Winter visitation to YNP has increased from 99,582 in 1989-90 to 127,380 in 1999-2000.

Over the last decade there has been a general, but uneven increase in winter visitation to

YNP. Peak visitation occurred in 1993-94 with 143,523 visitors; 142,454 people visited

in 1992-93. Visitation dropped to 119,539 in 1995-96, and increased little over the

following year, possibly due to poor snow conditions, unusually warm weather, and high

snowfall in the Midwest. Winter visitation to GTNP has increased more steadily over the

last decade from 44,845 in 1987-88 to 223,000 in 1999-2000.

Most of these winter visitors came to view wildlife, scenery, and thermal features, and

rated the presence of clean air, quiet, and solitude as very or extremely important to their

visits (Littlejohn 1996). One key difference between winter and summer visitors was inpark transportation. Snowmobiles, snowcoaches, cross-country skis, snowshoes, and

snowplanes offer oversnow recreational experiences that added to and detracted from

winter visitors’ overall enjoyment. Visitors can also enjoy the parks by driving on

plowed roads. In YNP and GTNP, an average of 75% of winter visitors ride

snowmobiles, 12% ride in snowcoaches, 20% use cross-country skis, 2% use snowshoes,

and 22% drive automobiles (Littlejohn 1996).

Group Origins, Types, Characteristics, and Previous Visits

Most people who visited YNP from outside Wyoming came from Montana, Utah, Idaho,

and Minnesota. For GTNP and the Parkway most non-Wyoming visitors came from

Idaho and California (Littlejohn 1996). Visitor origins may have changed over the last

decade. A 1989-90 survey found that YNP visitors were from (in order) Montana,

Minnesota, Washington, Utah, and Wyoming (Bath 1994).

Snowmobilers from Wyoming, Montana, and Idaho heavily use areas within their own

states for snowmobiling. For example, about 84% of snowmobile days for Wyoming

residents were spent on the state trail system; 7.9% were in YNP, and 1.4% were in

Grand Teton (Taylor et al 1995). Montana residents spent an estimated 12% of their

snowmobile activity days on trips that started at West Yellowstone; nonresidents were

estimated to have begun over 75% of their snowmobile activity days from West

Yellowstone (Sylvester and Nesary 1994). The number of days snowmobiling in

Montana by nonresidents increased from about 108,000 activity days in 1987-98 to

185,000 in 1993-94 (Sylvester and Nesary 1994).

More than 33% of YNP visitors were in family groups and 29% were with friends.

Groups of six or more comprised 37%; 29% were in groups of two. About 38% of
VISITOR EXPERIENCE

189

GTNP and the Parkway visitors were families, and 30% were groups of friends.

Snowmobilers tended to be younger than other categories of visitors (Littlejohn 1996).

YNP’s average winter visitor is a highly educated, relatively wealthy, middle-aged white

male. The average age of winter visitors to YNP in 1998 was 45 years old; over half

were college graduates; almost 70% lived in a community of 5,000 or more; and their

average household income fell between $60,000 and $80,000. Thirty percent of the

respondents reported annual incomes over $100,000 (Borrie et al. 1999).

More than half of YNP visitors stayed more than one day and 55% had visited the park

previously during the winter. Half of GTNP and the Parkway visitors stayed more than

one day, and more than half had visited the park previously during the winter (Littlejohn

1996).

Borrie et al. (1999) found that 84% of the respondents to their winter survey stayed the

night near YNP. Most respondents, over 78%, spent the night in a hotel or motel outside

YNP. For the overall park sample, West Yellowstone, Jackson, Bozeman and Big Sky

were the most frequently visited communities for overnight stays (Borrie et al. 1999).

Twelve percent of respondents spent at least one night of their visit in a hotel inside the

park. Fifty-five percent of respondents spent more than one day inside YNP and 7%

spent five or more days inside the park. Of those respondents that recreated outside of

YNP, 41% did so for more than two days (Borrie et al. 1999). Duffield et al. (2000a)

found that of those survey respondents who entered YNP on snowmobiles, 42% had

rented their machines. In contrast 70 % of respondents from the Borrie et al. (1999)

survey rented their machines.

Visitor Surveys

A 1997 survey of YNP snowmobilers and snowcoach riders found a range of responses

when asked about the importance of various indicators of quality recreational experience

in YNP and GTNP. Thirty-two percent felt that the percentage of time in sight of other

vehicles was unimportant, while 40% indicated that it was important. For 35% the sound

of other vehicles was unimportant, and for about 26% it was important. About 87% of

respondents indicated that the condition of groomed trails was important (Borrie et al.

1997).

A 1998-99 survey of YNP winter visitors found support for sound and emission

standards on snowmachines, more information and interpretation, stricter enforcement of

rules, and more trails and locations for recreation. Closing roads to oversnow vehicles,

restricting groomed roads to snowcoaches, and plowing the road from West Yellowstone

to Old Faithful were the least supported among respondents (Borrie et al. 1999).

A survey of motorized recreational equipment owners in Idaho found concerns that

availability of recreational lands could diminish or become more difficult with limits to

visitor use of areas:
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“Recreationalists [sic] are concerned about their access to natural resources.

They are finding that access is becoming limited and that it is more difficult for

them to enjoy the resources today than it has been in the past” (Strategy Group

1994).

An Idaho survey of cross-country skiers (resident and nonresident) found overwhelming

support (85%) for the separation of skiers and snowmobilers (Parrish et al. 1996). Other

desirable characteristics included having trail maps at parking areas, designated parking

areas, restrooms, and warming huts. Most (52%) preferred to ski on groomed trails, and

19% preferred ungroomed trails.

An Idaho survey of snowmobilers (resident and nonresident) found that 57% disagreed

that the current amount of lands open to snowmobiling is adequate, and 84% would like

to see more lands opened to snowmobile use. Groomed trails, well-marked trails, and

off-trail opportunities added the most to the snowmobilers’ experiences. Other

characteristics that added to the experience included having designated parking areas,

trail maps at the parking area, restrooms, and warming huts (Parrish et al. 1996).

Wyoming snowmobilers felt that the greatest needs for improvement of snowmobiling

were better trail maintenance, additional trail development, and better trail signing

(Taylor et al. 1995). A Montana study found that nonresident snowmobilers, when asked

to rate the importance of various snowmobile facilities, chose (in descending order) trail

maps, trail markers and signs, groomed trails, road signs to trailheads, and loop trails.

Resident snowmobilers, when asked the same question, were most interested in trail

maps, long trails, trail markers and signs, loop trails, and outhouses at trailheads

(Sylvester and Nesary 1994).

Activities

Most visitors also participated in winter recreation outside the parks, in national forests

and other recreational areas. Snowmobiling and skiing were the most popular pursuits

(Littlejohn 1996). National forests and other recreational areas in states immediately

bordering the parks offer more opportunities for winter recreation, and receive much

more use than the three NPS areas. Borrie et al. (1999) reported that over half the

respondents to their survey also skied or snowmobiled in areas outside YNP.

Snowmobiling was the most popular activity for visitors entering the East and West

Entrances, 93% and 89% respectively. Cross-country skiing was the most popular

activity for visitors to the North Entrance of YNP and to Grand Teton National Park.

Over 70% of North Entrance visitors indicated that wildlife viewing was a primary

activity during their visit. Viewing geysers was popular with West Entrance visitors.

Between 9 and 10% of visitors listed snowcoach tours as a primary activity.

Visitors’ Values and Expectations

People care about YNP as a “place of scenic beauty, where wildlife is protected, and

where everyone should visit” (Littlejohn 1996). Survey respondents cared least about

YNP as an economic resource. The top three reasons people visited YNP in the winter
VISITORS’ VALUES AND EXPECTATIONS

191

were to view natural scenery, have fun, and view bison. YNP visitors reported gaps

between importance of several characteristics of their visit and the degree of satisfaction

with the experience for that characteristic. For example, the importance of “experience

the tranquility” was sixth, while the satisfaction with that characteristic was 18th.

“Experience peace and quiet” was rated 14th in importance, and 25th in satisfaction.

“Get away from crowds” had the largest gap: it was 17th in importance, and 40th in

satisfaction. This indicates people feel that the values of tranquility, peace and quiet, and

solitude are important and anticipated, but that they were often dissatisfied with the

actual experience (Borrie et al. 1999).

A 1994 survey of winter visitors to the three parks (Littlejohn 1996a) asked visitors for

the primary reasons for their visit (respondents could list more than one activity). Table

52 summarizes the results. A similar survey completed in 1995 by the NPS validated

these results (NPS 1996b).

Table 52. Survey: Primary reasons for visitation.

Reasons for Visit YNP GTNP

View scenery 76% 73%

View wildlife 76% 68%

Take photographs 63% 66%

Snowmobiling 61% 30%

Cross-county skiing 29% 59%

Downhill skiing 11% 27%

Snowshoeing 1% 17%

Satisfy curiosity - 35%

Snowmobilers who reside in Montana and nonresidents vacationing in Montana were

asked to give reasons for engaging in their sport (Sylvester and Nesary 1994). Results of

this poll are given in Table 53.
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Table 53. Survey: Important reasons for snowmobiling.

Reason Residents Nonresidents

Observe scenic beauty 81.5% 87.7%

Take in natural surroundings 68.7% 84.2%

Enjoy smells and sounds of nature 57.2% 55.9%

Understand the natural world better 21.1% 30.3%

Learn more about nature 22.6% 33.8%

Get away from other people 41.5% 37.7%

For solitude and privacy 38.4% 45.1%

So my mind can move at a slower pace 19.9% 24.6%

In 1998 Teton County, Wyoming conducted a survey of county residents concerning

their opinions on winter use in Yellowstone and Grand Teton National Parks and the

John D. Rockefeller, Jr., Memorial Parkway (Teton County 1998). Respondents to this

survey were asked, regardless of usage, what they liked and disliked about the parks in

winter. In Yellowstone snowmobiling was the number one “like” answer (43%) among

respondents, who had at some time visited Yellowstone, while beauty was the number

one response for non-users. For GTNP cross-country skiing was the most popular “like”

response (27%) among users and beauty was most popular among non-users (38%). Of

the “dislikes” for YNP, responses were evenly distributed among users and non-users,

who gave the following responses: dislike snowmobiling, snowmobiling traffic,

snowmobile pollution, snowmobile noise, and crowds. For GTNP respondents did not

like the cost, snowmobiles, snowmobiles off trail, and crowds. Users (51%) and nonusers (61%) supported limits on snowmobiles. A smaller percentage of respondents

supported limiting snowmobiles in GTNP with 47% of users and 40% of non-users

supporting limits. However, regarding overall visitation, most survey respondents felt

that current levels of visitation were the right amount (66% of users and 57% of nonusers in YNP). In GTNP 84% of users and 75% of non-users felt that current use levels

were about right.

During the 1998-1999 winter and summer seasons the NPS sponsored three surveys

relating to the socioeconomic impacts of winter management changes within the three

park units. The first survey targeted winter visitors within the GYA (Duffield et al.

2000a). The other two surveys targeted summer visitors to YNP (Duffield et al. 2000b)

and the U.S. population as a whole, as well as local and regional residents (Duffield et al.

2000c). The results of these surveys may be found in this chapter in the section

Socioeconomics, Social Values. Although the results are not reiterated here in their

entirety, several findings from the survey are pertinent to the discussion of visitor

experience and satisfaction presented below.

As one might expect, respondents to the three surveys differed somewhat

demographically. Winter survey respondents, as mentioned previously, were primarily

white (99%), well educated, and relatively wealthy. Sixty-six percent of winter survey
MEASURES OF VISITOR EXPERIENCE AND SATISFACTION

193

respondents were male. Summer visitors were predominately white (98%) and male and

female respondents were evenly split at 50%. The national telephone respondents were

also predominantly white (91%), but a higher percentage of other ethnic and racial

groups were represented. Of this group of respondents 6.5% were African American;

2.8% were Asian; 1.3% were American Indian; and 6.8% were “Other”. Like the

summer survey, respondents to the telephone survey were evenly mixed between males

and females.

Although all respondents favored oversnow access to the parks, the summer and

telephone respondents were evenly divided between preferring access by snowcoach only

and access by snowmobile. A larger portion of the telephone and summer respondents

also expressed a preference for limiting use to skiing and snowshoe access only. Overall

respondents to all the surveys indicated concern about the welfare of wildlife. When

questioned whether they would favor limiting access to the parks to protect wildlife

(bison in this case) regional and national telephone respondents and summer visitor

respondents favored closing roads, while local telephone and winter visitors favored

visitor access.

Measures of Visitor Experience and Satisfaction

Based on evaluation of the survey results, conclusions can be drawn about the most

important aspects of visitor experience. Eight factors were defined as important criteria

by which to gage the alternatives for winter use in terms of visitor experience:

• Opportunities to view wildlife. Winter visitors consistently rate wildlife viewing as a

primary reason for visiting the parks. Respondents to the surveys conducted by Duffield et

al. (2000a, 2000b and 2000c) were concerned about the possible disturbance of wildlife in

the winter. There also appeared to be support from regional and national survey

respondents to accept changes in access policy if there was a corresponding benefit to

wildlife.

• Opportunities to view scenery. Winter visitors rate viewing scenery as the primary reason

for visiting the parks.

• The safe behavior of others. Both snowmobilers and skiers rate safe behavior as important

and indicate that it influences the enjoyment of their visit.

• Quality of the groomed surface. More than 80% of winter visitors rate the quality of the

snow surface as very important.

• Availability of access to winter activities or experiences. Nearly all winter visitors

surveyed by Borrie et al. (1999) support oversnow mechanized access, as opposed to

plowed roads. Winter respondents to the 1998-99 winter survey (Duffield et al. 2000a)

also favored oversnow access for snowmobiles. Respondents to the summer visitor sample

(Duffield et al. 2000b) and the phone sample (Duffield et al. 2000c) were more evenly

mixed between groomed roads for snowcoaches and groomed access for snowmobiles.

Plowed roads also received very low support in the summer and telephone surveys.

• Availability of information. Most respondents are highly supportive of management

actions that provide readily available information about winter opportunities or conditions

for safe travel.

• Quiet and solitude. Most survey respondents feel that natural quiet and solitude were

important to their park visit. Many were dissatisfied with their experience in this regard.
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• Clean air. Clean air is important to most visitors surveyed. This is supported by past

national survey results that indicate the recreating public most highly values clean air in

their visits to public lands.

ADJACENT LANDS

The GYA was initially delineated and described in the Greater Yellowstone Coordinating

Committee report, An Aggregation of National Park and National Forest Management

Plans (1987). Within the context of this EIS, which refers not only to public lands in the

GYA but also to states, counties and communities, the aggregation report is appropriate

for describing lands adjacent to the parks, as follows.

The description of GYA land ownership in the report, which excluded the southern

portions of both the Bridger Teton and Shoshone National Forests, shows a mix of

federal, state, and private lands. The 31,000 square miles in the GYA are comprised of

the following ownerships or jurisdictions:

• National forests (51%)

• Private ownership (24%)

• National parks (13%)

• Other federal agency jurisdictions (BLM, USFWS, and Bureau of Reclamation) (5%)

• Indian reservations (4%)

• State owned lands (3%)

For the purposes of this Final Environmental Impact Statement (FEIS), it is reasonable to

include both the southern portions of the Bridger Teton and Shoshone National Forests.

Significant amounts of winter recreational use occur there, and could be affected by

changes in national park management. Including the southern portions of the above

national forests would expand the study area and include all the above-listed ownerships

or jurisdictions in about the same proportion.

Apart from the federal jurisdictions and lands involved, lands of three states (Wyoming,

Montana, and Idaho) and 17 counties are considered part of the GYA study area. The

geographic relationship of all entities is shown on the GYA map found in Chapter I.

Discussions of the social and economic relationships among federal, state, and local

governments may be found in the Socioeconomic section of this chapter. Information

was provided by the Jackson Hole Chamber of Commerce to assist in preparation of the

Socioeconomic section. This included lodging occupancy numbers for December 1996

through March 1999, sales and use tax breakdown from July 1996 through June 1999,

winter airline load factors for 1996 through 1999, and winter airline seats available

versus seats sold from 1996 through 1999. Teton County, Wyoming provided the report

Draft Summary of Socio-Economic Conditions, Teton County, Wyoming (September

1998). Park County, Wyoming provided the May 1999 report Economic Importance of

the Winter Season to Park County, Wyoming (Taylor 1999). A list of the information

provided by the state and county cooperating agencies may be found in Appendix A.
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195

About 95% of the perimeter of GTNP, YNP, and the Parkway abuts national forest lands.

A high percentage of the national forest system along this common boundary is in

congressionally designated wilderness, and inventoried or other roadless areas. (Note:

Roadless areas as described in RARE II, and subject to the current USFS moratorium on

new road construction.) Other lands are in wildlife preserves, such as the National Elk

Refuge, or other similar designation. Near the gateway communities (Jackson, Gardiner,

Cooke City, and West Yellowstone) to both YNP and GTNP, mostly private lands abut

the parks. There is a significant amount of private land within the external boundaries of

GTNP, mostly east and south of Moran, and along the Snake and Gros Ventre River

corridors. There are isolated sections of state land near, in, or abutting the southern

portion of GTNP, and abutting the northwest corner of YNP.
196

CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

INTRODUCTION

This chapter contains the scientific and analytical foundation for comparisons between

the alternatives. The alternatives are designed to define issues sharply and provide a

clear basis of choice. Alternative effects comparisons in Chapter II are based on this

information.

A number of people commented that the Draft Environmental Impact Statement (DEIS)

contained inaccurate, bad, or no scientific basis. Most such statements were

accompanied by a statement of opposition to the DEIS preferred alternative. An

Environmental Impact Statement (EIS) is not a scientific document per se (40 CFR

1500.4(i)). It is not necessary to repeat the entire volume of detail on a particular subject,

and it is encouraged to cite literature or tier to other analyses to the greatest degree

possible to reduce the bulk of a document (40 CFR 1500.4(i) and (j)). An EIS is intended

to disclose environmental effects over a range of alternatives. It is meant to provide

enough information, both qualitatively and quantitatively, to display the relative

differences among the alternatives in subject areas most pertinent to the decision to be

made (40 CFR 1500.4(f)). The scientific integrity of an EIS is demonstrated by

disclosing methods of analysis, defining terms and assumptions, and making explicit

references to sources of information used (40 CFR 1502.24). Council on Environmental

Quality (CEQ) Regulations allow an EIS to proceed even if there is incomplete or

unavailable information, and specifies processes by which to do this (40 CFR 1502.22).

This chapter first explains the methods and assumptions used for all resource impact

topics. Then for each alternative, it discloses direct and indirect environmental effects

for the range of resource impact topics, including effects on the human environment

(social and economic). The final part of the chapter consists of separate summary

discussions of effects for all alternatives, including:

• Cumulative impacts

• Effects on adjacent lands

• Adverse effects that cannot be avoided

• Irreversible or irretrievable commitments of resources

• The relationship between short-term uses of the environment

• Maintenance and enhancement of long-term productivity.
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197

The estimated costs of the alternatives are not considered an impact topic. Appendix F

provides relative costs of the alternatives.

CEQ regulations for the National Environmental Policy Act (NEPA) require that

agencies determine the environmental issues related to a proposed action that are

“deserving of study” (40 CFR §1500.4, §1501.7), and discuss them in proportion to their

significance (40 CFR §1502.2 (b)). This determination, and consequent level of

discussion for each impact topic, is reflected in the Affected Environment chapter and is a

necessary prelude to analysis.

The purpose and need for the proposed action is defined in Chapter I, along with a

determination of the issues to be analyzed in depth based on the scope of the purpose and

need (Major Issues). The issues to be analyzed in depth do not always correspond neatly

to individual analysis topics because of analysis complexities and resource

interrelationships. What follows is a guide to major issues and corresponding relevant

and related topics in the effects analysis. Since alternatives were formulated to define the

issues, this linkage is critical for the reader and the decision maker to see how

alternatives address the purpose and need for action.

Table 54. Major issues.

Impacts of the Proposed

Action on: Impact Topics Related to Major Issue:

Visitor Use and Access Visitor Access and Circulation

Visitor Experience Visitor Experience; Air Quality and Public Health; Natural

Soundscape; Public Safety

Air Quality Air Quality and Public Health; Visitor Experience

Soundscape Natural Soundscape; Visitor Experience

Human Health and Safety Air Quality and Public Health; Public Safety; Visitor Experience

Local Economies Socioeconomics

Natural Resources Natural Resources – Geothermal; Water; Wildlife; Soundscapes

ASSUMPTIONS AND METHODOLOGIES FOR EVALUATING IMPACTS

This analysis includes a description of whether effects are beneficial or adverse, and short

term or long term. The magnitude of the effect also is described in terms ranging from

negligible to major. Effects disclosed may be direct or indirect. The definition of the

level, or magnitude, of the impact may vary between impact topics, so individual

definitions are provided for each. The following definitions apply in general to the

effects analysis.
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Table 55. Types of effects.

Impact Category Definition

Beneficial effect A positive change in the condition or nature of the resource, usually with

respect to a standard or objective. A change that moves a resource toward its

desired condition.

Adverse effect A negative change in the condition or nature of the resource, usually with

respect to a standard or objective. A change that moves a resource away from

its desired condition.

Direct effect An effect that is caused by an action and occurs at the same time and place.

Indirect effect An effect that is caused by an action but is later in time or farther removed in

distance, but is still reasonably foreseeable.

Short-term effect An effect that in a short time will no longer be detectable as a resource returns

to its pre-disturbance condition. The period is generally less than 5 years.

Long-term effect A change in a resource or its condition that does not return to pre-disturbance

levels and for all practical purposes is considered permanent.

From an analysis standpoint there is a difference in types of effects relating to natural

resources versus items such as public safety or public health. Applying the definitions of

short-term or long-term effects to the public health is somewhat problematic. In most

cases it is assumed that public health or safety risks would be affected directly by a

management action, either improved or worsened. Therefore, the term or duration of

effect is only as long as the management action is applied. This effect is, therefore,

assumed to be short term since the action can be changed at any time to improve safety

and health risks. Conversely, it is not reasonable to assume that an identified health or

safety risk would be allowed to continue over the long-term.

For the rest of the analysis, including Natural Resources, all disclosed effects are

considered short term unless otherwise stated. In most cases, the duration of the impact

coincides with the duration of the action.

Socioeconomics

Introduction

The degree of impact can be quantified in some cases, such as when a model is used or

data are obtainable. Often only qualitative descriptions of impact from specialists or

scientific literature in similar cases are available. Table 56 defines the degree of impact

when it cannot be quantified.

Table 56. Definition of impacts to socioeconomics.

Impact Category Definition

Negligible The impact is at the lower levels of detection.

Minor The impact is slight, but detectable.

Moderate The impact is readily apparent and has the potential to become major.

Major The impact is severe, or if beneficial, has exceptional beneficial effects.
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199

Summary of Regulations and Policies

NEPA’s guiding regulations require analysis of social and economic impacts resulting

from proposed major federal actions if an EIS is being prepared. In addition Executive

Order 12898, dated February 11, 1994, “Federal Actions to Address Environmental

Justice in Minority Populations and Low-Income Populations” requires federal agencies

to assess the impact of actions on minority and low-income communities. Although there

are no specific regulations requiring protection of social values, impacts on them are

considered an important piece of the federal planning processes.

Assumptions and Methods

Between the last week of January and the first week of March 1999 winter visitors to

Yellowstone National Park (YNP) and Grand Teton National Park (GTNP) were

surveyed regarding their winter trips to the Greater Yellowstone Area (GYA) and their

opinions about winter management of the national parks in the GYA. Chapter III

describes key results of the survey. Economic parameters related to the regional

economy generally were derived from the winter user study using regional economic

input-output methodologies (Minnesota IMPLAN Group 1996). Also included in

Chapter III is a discussion of the results for two additional surveys: a 1999 survey of

summer visitors to YNP, and a national, regional, and local random household phone

survey. Economic parameters related to nonmarket values were derived from the winter

user study using contingent valuation model methodologies (Braden and Kolstad 1991;

Mitchell and Carson 1989).

Methodology for Estimating Changes in Winter Visitation Associated with

Socioeconomic Impacts

The primary source of data used to estimate winter visitation changes under different

park management policies was the 1999 winter survey of winter visitors to YNP and the

GYA (Duffield et al. 2000a). The following discussion focuses first on the information

needed to estimate visitation changes, and then the mechanics of estimating changes from

this information.

The following information was used to estimate impacts.

Total winter visitation to YNP, and GTNP, and the Parkway. This information

provided by the NPS was based on 1998-99 data for the West and East Entrances of YNP

as well as the Moose and Moran Entrances of GTNP, and 1997-98 data for the North

Entrance of YNP. The 1997-98 data was used because of questions regarding the 1998-

99 data, and because available information indicated that visitation had been relatively

stable through the North Entrance for 1997-98. The visitation data for the Moran

Entrance of GTNP was derived in three steps:

1. Adjusting the total December through March 1998-99 car counter data for the portions of

December and March not included in the winter season analysis;

2. Reducing the car count by an estimate of 25% non-recreational entries;
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3. Multiplying the result by an estimated 2.4 people per vehicle.

The estimate of visitors at the Moose Entrance was provided by GTNP as the sum of

skiers, snowmobilers, and an estimate of 60% of backcountry user-nights accessed

through this entrance (Terri Roper, pers. com., 2000). An estimated 117,666 visitors

entered GTNP at the Moose Entrance. Because some visitors enter the parks more than

one time on their trip to the area, the trip estimate is based on the total entrance count

reduced by 25% (Sacklin, pers. com., 1998). Therefore the estimated baseline visitation

level is 88,250 individual trips (including multi-day trips) to the parks between midDecember and the second week of March.

Percent of visitors from outside the analysis area. There were two analysis areas in

this study: the five contiguous counties surrounding the parks (Fremont, Idaho; Gallatin

and Park, Montana; and Park and Teton, Wyoming), and the three-state region of Idaho,

Montana, and Wyoming. The survey of winter visitors to the parks found that 85.9% of

winter visitors were from outside the five-county area, and 65.5% were from outside the

three-state region. A 17-county area was evaluated in the DEIS and refined to five

counties at the request of cooperating agencies.

Estimated percentage change in the number of trips to the parks. The winter visitor

survey addressed four possible policy changes in park winter access management

(Duffield et al. 2000a). The survey questions asked visitors how they would change their

anticipated visitation to the 17-county GYA in the winter months under different

management policies. To arrive at an estimated percentage change in trips, the responses

of individuals who said they would take either more trips or fewer trips were compared to

the baseline number of anticipated trips to the GYA. Two specific adjustments were

made:

1) A very small number of individuals from distant states (New Jersey, Pennsylvania, or

Alaska) who stated that they took an implausibly high number of trips from home to the

GYA during the 120-day winter season (25, 30, or 50 trips) were excluded from the

analysis.

2) A 120-day threshold was set for the winter visitor season. If a respondent indicated that the

threshold would be exceeded by additional visits to GYA, the response would be excluded.

For this reason, one response was excluded from the sample.

Total spent per trip within the analysis area. The 1999 winter visitor survey asked

respondents how much money they spent on their trip to the GYA. The survey also

asked the respondents to divide their total trip spending and estimate how much was

spent in the 17-county GYA verses the three-state region. These responses were

analyzed to calculate the average trip expenditure in the 3 states and in the 17-county

GYA for individuals that said they would increase their number of trips and those who

said they would decrease their trips. Spending was calculated on this disaggregated level

to capture any possible differences in trip spending between those who would increase or

decrease visitation under a policy change.
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201

Percent of the nights spent in the five-county analysis area. The winter visitor survey

asked respondents how many nights they spent in each of 19 towns in the 17-county

GYA. To estimate impacts on the smaller five-county area it was assumed that spending

would closely follow overnight stays. It was found that 85% of the overnight stays

detailed by winter survey respondents were spent in the five-county area.

Sampling Methodology and Adjustments to Sample Data

The sampling design for the winter user survey was based on the distribution of winter

use among five park entrances (YNP North, East, and West, and GTNP Moose and

Moran) during winter 1997-98. The sampling rate at the East Entrance was intentionally

doubled to yield more complete surveys from this lightly used entrance.

In the course of conducting consistency checks on the final winter survey database, it was

discovered that the sample allocation among the GTNP entrances was weighted too

heavily toward the Moose Entrance. The 1997-98 winter visitation statistics used for this

entrance included a substantial number of non-recreational visits. Since visitors through

the Moose Entrance are predominantly cross-country skiers, this sampling bias resulted

in an overrepresentation of skiers relative to snowmobilers in the sample. To correct for

this, the responses of GTNP skiers and snowmobilers were weighted in the final analysis

to reflect the true proportion of these groups in the winter visitor mix to GTNP.

Estimation of Visitation Impacts

The estimates of changes in direct visitor spending were calculated using the following

steps for each of the two analysis areas (five-county and three-state), and for each of the

four management changes:

1) Total winter visitation (88,250) was multiplied by the percent of visitors coming from

outside the GYA three-state region.

2) The resulting visitation from outside the impact area was multiplied by the estimated

percentage change to the number of trips as calculated from the responses to the YNP

winter visitor survey. This estimated percentage change in visitation took into

consideration the responses of those who said they would decrease their visitation under an

alternative as well as the responses of those who said they would either increase visitation

or not change their visitations to the area.

3) The respective reduction and increase in trips were multiplied by the mean trip expenditure

to the impact area for those who said they would decrease or increase trips, respectively.

4) The resulting estimated increase and decrease in trip expenditures were summed to arrive

at an estimated change in visitor expenditures.

5) The change in trip expenditures was input into an IMPLAN regional economic model of

the impact area to estimate the indirect and induced expenditure impacts resulting from the

estimated direct expenditure impacts.

6) Direct, indirect, and induced expenditure impacts were summed to arrive at total estimated

expenditure impacts for each management option and impact area.

7) Total estimated expenditure impacts were compared against the total impact area economic

baseline to arrive at an estimated percentage change in economic activity (output or

employment) for the area.
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In addition to the survey data described in the Chapter III, the cooperating counties and

states supplied a substantial number of local economic reports and associated data. These

reports were reviewed and, where appropriate, incorporated into the following analysis.

Appendix A contains a list of the documents supplied by the cooperators and reviewed in

preparation of this document.

The five-county GYA and three-state region were used for the socioeconomic impacts

analysis of alternative management actions. The primary economic impact associated

with the winter management alternatives concerns actions that are likely to change winter

park visitation levels. Estimated expenditure impacts on an area from reduced tourism

depend on 1) the percentage of visitors to a park, for example, that come from outside the

impact analysis area, and 2) the amount of their total trip expenditures that are spent

within the impact analysis area. The percentage of visitors from outside the analysis area

decreases as the size of the analysis area increases, while the percentage of their total trip

expenditures spent within the analysis area increases as the analysis area increases. The

five-county analysis area was chosen to represent the counties and communities where

most of the economic activity related to YNP and GTNP occurs. This change from the

DEIS, which evaluated a 17-county area, was made at the cooperating agencies’ request.

The estimated impacts associated with the alternatives are presented as impacts on the

specific analysis areas (five counties or three states). It is important to recognize,

however, that these analysis areas are not economically homogeneous, and any impacts

associated with alternative management actions would not be distributed evenly across

the analysis areas (see also Socioeconomics of the Regional Economy, Chapter III). The

counties and communities closest to the parks (specifically communities such as West

Yellowstone and Gardiner, which are heavily tourism dependent) would be much more

heavily impacted than more distant, larger, and more economically diverse communities

within the five-county area such as Bozeman or Jackson.

The following analysis of socioeconomic impacts to the five counties presents net

impacts to the five-county area. No specific estimates are made of shifts in visitation and

associated visitor spending within the GYA. It is likely that under alternative B for

example, there would be a shift in snowmobile related winter visitation from the West

Entrance of YNP to other areas such as the South and North Entrances. Consequently,

part of the lost tourism spending within the West Yellowstone economy would be gained

by Teton County, Wyoming and Gardiner and Cooke City, Montana.

Estimated impacts related to social effects and attitudes relied on standard methods in the

social sciences, including survey research and various standard statistical techniques.

Air Quality and Public Health

Visitors and park staff report haze, odors, and health-related issues from emissions in

areas where snowmobiles congregate (GYCC 1999). The EPA currently does not

regulate snowmobile emissions although it has recently indicated that regulations on
ASSUMPTIONS AND METHODOLOGIES FOR EVALUATING IMPACTS

203

snowmobiles will be proposed by September 2000 (EPA 1999). Such proposed rules and

regulations often require years before they can be implemented. Studies in YNP, GTNP,

and in laboratories analyzing the emissions of snowmobiles and the impacts of the

emissions on the environment and human health have shown that most wheeled-vehicles

are less polluting than 2-stroke engines (Snook and Davis 1997). The use of bio-based

fuels and biosynthetic lubricants, proper engine set up (such as tuning the snowmobile

engine for the elevation), and other 2-stroke engine technologies have shown to have

moderate reductions in emissions (White and Carrol 1998).

Increased recreational visitor use contributes to concerns about the impacts on air quality

from increased use of 2-stroke engines. Weather conditions, higher elevations, and large

numbers of visitors using snowmobiles contribute to concentrated pollution at YNP

(GYCC 1999). Destination areas such as Old Faithful, and road segments with greater

traffic such as the road from the West Entrance to Old Faithful often experience problems

with air quality. Visible adverse impacts (haze and odor) to air quality are short term,

depending upon the location and environmental factors such as wind. Studies are

underway to understand the long-term impacts of high polluting emissions on

environment and human health. The results of these studies are summarized in Chapter

III.

Modeling Methodology

To assess the relative impacts of the proposed winter use alternatives on ambient air

quality in the GYA, short-term air quality analyses were performed by means of

atmospheric dispersion modeling for carbon monoxide (CO) and particulate matter

(PM10). Table 57 summarizes six locations that were selected for the analyses based on

visitor activities and vehicle mix as specified in alternatives A through G. The air quality

study includes the inherent uncertainties of the model and the temporal and spatial biases

due to limited meteorological and emission data. The modeling input and output data are

presented in a separate report (EAEST 2000).

Table 57. Selected locations for modeling application.

Location Type

West Yellowstone Entrance Tollbooths

Old Faithful Staging Area Staging area

Flagg Ranch Staging Area Staging area

Mammoth to Northeast Entrance Plowed highway

West Entrance to Madison Groomed motorized route

Flagg Ranch to Colter Bay Groomed motorized trail/plowed road

For the West Entrance to YNP and the roadway links, the EPA model CAL3QHC (EPA

1995a) was used to predict the maximum hourly average concentrations of CO and PM10.

In addition persistence factors were applied to the results to estimate maximum 24-hour

average PM10 concentrations and maximum 8-hour average CO concentrations. For the
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204

staging areas, the EPA model ISCST3 (EPA 1995b) was used to predict the maximum

hourly and 8-hour average CO concentrations and maximum hourly and 24-hour average

PM10 concentrations. The predicted maximum concentrations of CO and PM10 attributed

to traffic conditions of the alternatives were then compared to those of the existing traffic

conditions (no action alternative) to determine the amount and direction of changes in

CO and PM10 concentrations. The contribution of each vehicle type to the generation of

CO and PM10 was also assessed.

The visibility assessment was conducted following the procedures outlined in the

Workbook for Plume Visual Impact Screening and Analysis (EPA 1992). These

procedures are designed to analyze the visibility impacts of plumes from industrial

stacks. The winter use visibility analysis requires the assessment of line and area source

emissions. The analysis techniques were adapted to meet this requirement using virtual

point source methods.

West Yellowstone Entrance

Two tollbooths or kiosks are present at the West Entrance to YNP where snowmobiles

and snowcoaches idle when entering the park to pay fees and obtain information. This

creates stop-and-go, delay, and queuing traffic conditions. In addition an express lane

exists at a third tollbooth in which traffic is designed to be freer flowing. To model the

air quality impact of these traffic conditions, the EPA air quality model CAL3QHC was

used. CAL3QHC predicts concentrations of inert pollutants from both moving and idling

motor vehicles at roadway intersections. It includes the line source dispersion model

CALINE3 (Benson 1979) and a traffic algorithm for estimating vehicular queue lengths

at signalized intersections. Even though the West Entrance is not a signalized

intersection, it presents the characteristics of one (e.g., delay approach, idle, and

acceleration). The CAL3QHC model requires meteorological, site geometry, traffic, and

emission parameters and data as critical inputs. Only the morning case was considered

since it represents the most limiting traffic scenario occurring on a daily basis (DEQ

2000). A referential system with origin at the second or middle tollbooth was used to

allocate the end points of the links and the receptor locations. Nine links representing the

approach, queue, and departure links of each of the three lanes were defined. The end

point coordinates of the links extend up to 1,000 feet for each link. Ten receptors were

located outside the mixing zone, 200 feet apart along the northern and southern side of

the entrance.

Using data from a February 2000 West Entrance snowmobile monitoring project (NPS

2000a) and the winter motorized average mean daily use (AMDU) scenarios (NPS

2000b), a methodology was developed to estimate the peak hourly traffic volume for

each alternative. The traffic counts from the monitoring project indicate that the period

between 9 A.M. and 10 A.M. represents the peak traffic hour, and that an average of 309

snowmobiles entered the park during that time. The average total daily entrance was 923
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snowmobiles. This implies that about 33% of daily snowmobiles entered the park during

the peak hour.

The winter motorized-use scenarios indicate that the ratio of the AMDU to the average

peak day use of snowmobiles is 0.57 for alternative A (no action alternative). Assuming

these percentages hold true for the other alternatives and for each vehicle type, the hourly

peak traffic volume may be calculated as AMDU x 0.33/0.57, where AMDU is the

average mean daily use. Videotapes recorded during the monitoring project indicate that

the average idle time length at the two tollbooths is 30 seconds and the average approach

speed is about 10 mph. Although the third lane was designed to be free flowing, it has

been observed that on average motorists idle for about 5 seconds. For alternative G, it

was assumed that no express lane exists and that all lanes have the same idle time of 30

seconds.

The composite wintertime CO and PM10 idle emission factors for the queue links and

traveling emission factors for the approach and departure links were calculated based on

the traffic volumes and the emission factor for each vehicle type. The traveling CO

emission factors for automobiles, trucks, vans, and buses were obtained from the EPA

emission factors publications for an average speed of 10 mph, high altitude location, and

desired fuel type (EPA 1998a). The traveling PM10 emission factors for automobiles,

trucks, vans, and buses were estimated from the EPA emission factor model PART5

(EPA 1995c) for an average speed of 10 mph, high altitude location, average fleet mix,

and desired fuel type. For the Bombardier snowcoach, pre-1970 gasoline light-truck

emission factors were used. Idle emission factors were obtained from the EPA idle

emission factors publication (EPA 1998b). Since gasoline-fueled vehicle idle PM10

emissions are negligible, they were set to 0.001 grams/hour in the modeling inputs. The

snowmobile emission factors were obtained from the Southwest Research Institute

studies (White and Carroll 1999). An additional assumption was that 60% of all personal

light-duty vehicles entering the park are light-duty trucks and 40% are automobiles.

Meteorological conditions considered for this analysis include low wind speed of 1

meter/second, stable atmosphere (class 6), and a low mixing height of 50 meters, which

was derived from the average morning mixing height data for the Jackson Hole Airport

during January and February 200030. The ambient background concentrations of CO and

PM10 were estimated following the guidelines of 40 CFR 51, Appendix W using available

monitoring data collected from January 12 to March 28, 1995 in the town of West

Yellowstone (NPS 1996a). They were estimated to be 3.0 ppm for 1-hour average CO

and 23.0 μg/m3 for 24-hour average PM10. A surface roughness of 283.0 centimeters

(cm) representing a fir forest was selected. Finally, for PM10 modeling, a settling velocity

and deposition velocity of 0.5 cm/s were selected (Zanneti 1990).

 

30 This scenario was used because the logical objective for this modeling effort is to replicate some conditions

under which violation of a standard could reasonably be expected. These conditions are not unrealistic.
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Roadway Segments

The selected road segments also were modeled using the CAL3QHC model. When

executed without a queue link, CAL3QHC behaves like CALINE3, the recommended

model for road segments. The first road segment selected is a 10 kilometers (km) stretch

in YNP between the West Yellowstone Entrance and the Madison Junction, starting

about 3 km from the West Entrance. It was subdivided into four short links because of

directional changes in the roadway. The second road segment is also a 10 km stretch in

GTNP between the Flagg Ranch staging area and Colter Bay Village, starting about 12

km south of Flagg Ranch. It contains an elevated groomed motorized trail for

alternatives A, B, and C. Therefore, it was subdivided into eight short links, four for the

main road and four for the adjacent trail. The third road segment is a 6 km stretch of road

between Mammoth Hot Springs and Tower Roosevelt in north-central YNP, starting

about 10 km east of Mammoth Hot Springs. It is characterized by wheeled-vehicle use

only and was subdivided into four short links.

Within the model, receptors were placed on both sides of the road segment links outside

the mixing zone, and meteorological conditions defined in the West Entrance scenario

assumptions were used. The fleet mixes on the road segments were determined using the

methodology explained in the West Entrance scenario. The composite wintertime

traveling emission factors of CO and PM10 were calculated similarly to the West Entrance

scenario, but for an average speed of 35 mph. The 24-hour average PM10 background

concentration was integrated from the IMPROVE network data to be 5.0 μg/m3. Because

no CO monitor exists inside the park, the West Entrance 1-hour average CO background

concentration was used. However, the West Entrance CO and PM10 background

concentrations were used for the West Entrance to Madison junction road segment.

Staging Areas

The two staging areas modeled in this analysis were Old Faithful and Flagg Ranch. Old

Faithful contains three main parking areas designed for visitors, while Flagg Ranch

contains two main parking areas designed for visitors, guides, and outfitters. Compared

to the West Entrance and the roadway segments, traffic in both staging areas is believed

to be in idling or in slow-moving mode for relatively long periods. The staging areas

were modeled as area sources using the EPA ISCST3 model. ISCST3 is a refined

dispersion model based on the steady-state Gaussian plume equation designed to estimate

concentration or deposition levels for each source-receptor combination. It requires

source characteristics, source strength, hourly meteorological data, receptor locations,

and terrain data as critical input data. In each of the two staging areas, a single area

encompassing the major parking lots was drawn and used as the modeling area.

Based on the park official estimated number of vehicles present in the staging areas on a

peak winter hour and the winter motorized average mean daily use scenarios (NPS

2000b), a methodology was developed to estimate the peak hourly traffic volume. It was

assumed that the ratio of the average daily mean use of the roadways leading to the

staging area for a given vehicle type to the total daily mean use was the same in the
ASSUMPTIONS AND METHODOLOGIES FOR EVALUATING IMPACTS

207

staging area. It was also assumed that 20% of the machines are idling at Old Faithful,

and that all machines idle for an average of 10 minutes at Flagg Ranch. The peak hourly

vehicle number was then calculated by multiplying the peak vehicle population by the

vehicle type ratio and the idle time. Moreover, for alternative G, the number of

snowcoaches present in the staging areas was calculated by assuming that former

snowmobile users would utilize the snowcoach fleet, and snowcoaches were assumed to

be late model light-duty truck conversions.

The composite wintertime CO and PM10 idle emission factors were calculated similar to

the West Entrance to YNP scenario. To obtain the hourly surface and upper air

meteorological data required by ISCT3, the Jackson Hole Airport data for the winter

months were obtained from the National Climatic Data Center and processed. In the

model, a gridded receptor system was placed around the areas using a 100-meter spacing

up to a distance of 1,000 meters. The 24-hour average PM10 background concentration

was integrated from the IMPROVE network data to be 5.0 μg/m3. Since no CO monitor

exists inside the park, the West Entrance 1-hour average CO background concentration

was used.

Impacts

The discussion of impacts of alternatives on vehicle emission exposure focuses on the

exposure of employees, visitors, and snowmobile operators and riders to CO and PM10

worst-case air pollutant levels predicted by the air dispersion modeling. The intensity of

an impact is categorized as negligible, minor, moderate, or major relative to alternative

A, the no action alternative. For this analysis, the definition and intensity of the impact

categories are summarized in Table 58. All impacts on air quality and public health are

defined as short term (see introduction to Assumptions and Methods for Evaluating

Impacts).

Table 58. Definition and intensity of impacts to air quality and public health.

Impact Category Definition Intensity

Negligible The impact on public health is not measurable or perceptible. <5%

Minor

The impact is measurable or perceptible and is localized within a

relatively small area. However, the overall exposure would not be

affected.

5-20%

Moderate

The impact is sufficient to cause a change in exposure, but remains

localized. The change is measurable and perceptible but could be

reversed.

21-50%

Major The impact is substantial, highly noticeable, and may be

permanent. >50%

Visibility

Visibility impacts are assessed by whether the air pollution emissions from an alternative

are likely to cause a visibility impairment that would be perceptible to an observer.
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Screening threshold values described in the Workbook for Plume Visual Impact

Screening and Analysis (EPA 1992) are used.

Public Safety

Public safety, for the purposes of this analysis, relates to dangerous incidents, motor

vehicle accidents, and avalanches potentially involving park visitors and employees.

Public safety is evaluated in relation to existing conditions as documented in the Affected

Environment.

Impacts to public safety at YNP, GTNP, and the Parkway are closely related to changes

in winter use activity levels, use of trails by different user groups, and the implementation

of safety-oriented policy changes. Changes in activity levels affect the potential for

conflict among and between user groups. For example, if participation in a particular

activity is expected to decrease through the implementation of an alternative, the

potential for incidents among that activity group will be expected to decrease. The use of

trails for different activities also increases the potential for incidents or conflicts between

user groups. Speeds associated with motorized use inherently decrease reaction time

when nonmotorized participants are encountered on the same trail.

The impact levels identified for each alternative are relative to those stated for alternative

A. All impacts on public health are defined as short term (see the introduction to

Assumptions and Methods for Evaluating Impacts).

Table 59. Definition of impacts to public safety.

Impact Category Definition

Negligible The impact to public safety is not measurable or perceptible.

Minor The impact to public safety is measurable or perceptible, and is limited to a

relatively small number of winter use visitors at localized areas. Impacts to

public safety may be realized through a minor increase or decrease in the

potential for visitor conflicts in current accident areas.

Moderate The impact to public safety is sufficient to cause a permanent change in

accident rates at existing low accident locations or create the potential for

additional visitor conflicts in areas that currently do not exhibit noticeable

visitor conflict trends.

Major The impact to public safety is substantial either through the elimination of

potential hazards or the creation of new areas with a high potential for serious

accidents or hazards.
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Geothermal Features

Visitor access can cause degradation to geothermal features. Increases or changes in

access may increase the degree to which geothermal features are impacted. Geothermal

areas near roads or developments are more likely to be impacted than geothermal areas

located in the backcountry. YNP monitors and seasonally removes trash from

geothermal features, providing an indirect means of measuring the impact of visitor use

on these areas. In addition the knowledge of park staff was utilized to describe the

current types of damage that are occurring to geothermal features in the parks.

Water Resources

Studies on snowpack and snowmelt chemical analysis are being conducted to determine

the effects, if any, of 2-stroke engine emissions on water quality. Until these studies are

complete, it may be assumed that emissions and discharge from snowmobiles may

directly or indirectly contribute to water pollution, particularly in areas where roads

parallel riparian and wetland areas. The closer the road is to water or wetland areas, the

higher the risk of water pollution. To assess the potential risk of pollutants entering

surface and subsurface waters, road segments, upon which winter motorized use occurs

(based upon their proximity to surface waters or wetlands as shown on the U.S. Fish and

Wildlife Service’s (USFWS) National Wetland Inventory maps), are categorized as

“high,” “medium,” or “low” risks for water quality and aquatic resources degradation.

“High” risk segments are within 100 meters of rivers, lakes or other waters for a

significant portion (76% to 100%) of the road segment, thereby posing a higher potential

or risk of pollutants entering surface and subsurface waters. “Medium” risk segments are

within 100 meters of rivers, lakes, other waters, or wetlands for a moderate portion (51%

to 75%) of the road segment. “Low” risk segments are within 100 meters of rivers, lakes

or other waters less than 50% of the road segment. Assessment of risks is the initial step

in assigning an impact level to an action.

Impacts to water and aquatic resources are defined at various levels described in Table

60. Consideration of impacts and their disclosure is a function of risk, intensity, duration,

and extent.
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Table 60. Definition of impacts to water and aquatic resources.

Impact Category Definition

Negligible An action that is a low risk of degrading water quality because of sufficient

separation between the action and conveyance routes to the resource, or

because the action does not generate impact sources harmful to water

resources.

Minor An action that could represent a low risk of degrading water quality, involving

non-toxic or non-point and minor sources of pollution that do not persist in

the environment.

Moderate An action that could represent a moderate risk of degrading water quality by

proximity to surface water, involving sources of pollution that are persistent

in the environment and may be toxic to aquatic biota, but which are mostly

local in extent.

Major An action that could represent a high risk of degrading water quality by

immediate proximity to surface water, involving sources of pollution that are

persistent in the environment and may be toxic to aquatic biota beyond the

local area.

Wildlife, Including Federally Protected Species and Species of Special

Concern

Regulations and policies for management of wildlife underlie the analysis determinations

presented in the consequence discussions. A summary of this direction (including

legislation and executive orders) is presented in Appendix C.

Methods

The following sources of information were used to assess the level of impact on wildlife:

1) Scientific literature on species’ life histories, distributions, habitat selection, and responses

to human activities.

2) Site-specific information on wildlife species in the parks, including complete and on-going

studies (when available), and the professional judgment of park biologists familiar with the

management concerns related to individual species.

The results of this information review are included in its entirety under alternative A;

subsequent alternative analyses compare and contrast effects relative to alternative A.

The effects analyses for wildlife is structured according to the types of actions that are

addressed programmatically in all alternatives. These are: (1) the effects of groomed

roads and trails; (2) the effects of motorized oversnow use of groomed roads and trails;

(3) the effects of plowed roads; 4) the effects of motorized use of plowed roads; (5) the

effects of nonmotorized use of groomed and designated ungroomed routes; (6) the effects

of unregulated backcountry nonmotorized use; and (7) the effects of the presence and use

of winter support facilities (i.e., warming huts and campgrounds). Variations in

alternatives that mitigate the impacts of these actions are included and reflected in the

statements of effects. Additional recommended mitigation is provided at the end of the

wildlife analysis for each alternative. Wildlife effects discussions are grouped under the
ASSUMPTIONS AND METHODOLOGIES FOR EVALUATING IMPACTS

211

general headings of Ungulates, Federally Protected Species, and Species of Special

Concern.

In addition to the effects analysis presented in this document, a biological assessment

(BA) was prepared as required by Section 7 of the Endangered Species Act to assess the

effects of the preferred alternative on federally protected species. Effects in the BA were

described as mandated by the USFWS, and include a determination of whether the

preferred alternative, including all related actions, may or may not affect each federally

protected species. Readers are advised that this type of determination, in which the

alternative is treated in its entirety, is different from the effects analysis presented in this

EIS. As stated in the preceding paragraph, the level of impact associated with each

action under each alternative is defined; the impact of the alternative as a whole is not

defined. Table 61 defines the levels of impact on wildlife in this document.

Table 61. Definition of impacts to

wildlife, including federally protected species and species of special concern.

Impact Category Definition

No Effect An action that does not affect a species.

No Known Effect An action that may affect a species elsewhere but for which there are no

demonstrated impacts known to occur in the parks.

Adverse

Negligible Effect

An action that may affect a population or individuals of a species, but the effect

will be so small that it will not be of any measurable or perceptible

consequence to the population.

Adverse Minor

Effect

An action that may affect a population or individuals of a species, but the effect

will be small; if it is measurable, it will be a small and localized consequence

to the population.

Adverse Moderate

Effect

An action that will affect a population or individuals of a species or a natural

physical resource; the effect will be measurable and will have a sufficient

consequence to the population but is more localized.

Adverse Major

Effect

An action that will noticeably affect a population or individuals of a species or

a natural physical resource; the effect will be measurable and will have a

substantial and possible permanent consequence to the population.

In GTNP and the Parkway five areas that have been shown to be particularly sensitive to

wintering wildlife have been regulated and are closed to use throughout the winter

season. The areas are shown on all alternative maps, and are listed below along with

short descriptions of the wildlife use. Closure to all winter uses eliminates the potential

effects of the actions listed above on wildlife species.

• The Snake River floodplain, from the confluence of the Buffalo Fork (at Moran Junction)

downstream to the Menor’s Ferry crossing north of the Moose development, provides winter

habitat for elk, moose, bison, trumpeter swans, bald eagles, and wolves.

• The Willow Flats area (northwest of the Jackson Lake junctions) including the Second, Third,

Pilgrim, Spring, and Christian Creeks drainages south and west of US 89/287, but excluding

the Jackson Lake Lodge, provides important habitat for moose.

• The Buffalo River floodplain and the Uhl Hill area east of Moran Junction provides winter

habitat for bison and elk and winter prey for wolves.

• Kelly Hill (southeast of Moose Junction) near the Gros Ventre River provides important bison

and bighorn sheep winter range.

• Static Peak provides additional bighorn sheep winter range.
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In YNP a closure is enforced on McMinn Bench, an important winter range for bighorn

sheep.

Natural Soundscape

Analysis Approach for Determining Noise Impact on the Natural Soundscape

Different metrics are presented to assist in evaluating the potential impacts of noise on

the natural soundscape. “Audibility” of vehicles (oversnow vehicles, autos, and buses) is

an approach that is easily understood and can be used to compare different types of

vehicles and different project alternatives. Audibility is expressed in terms of distances

to the limits of vehicle audibility, acres of park land affected by audible vehicle traffic,

and the percentages of time vehicles are audible in sections of park land. “Sound level”

is used to convey the loudness of vehicular sound at different distances from park roads.

To compare the audibility of different vehicle types, the greatest distance that an

individual vehicle pass-by can be heard was calculated. Since this distance to the limit of

audibility depends upon both the background (ambient) sound level and the rate at which

sound drops off with distance, calculations for different background sound conditions and

different terrain types were performed.

The following paragraphs first summarize how ambient levels were determined, and then

present the measured sound levels of various vehicles. Next, the method of using these

data to compute the maximum distances at which the various vehicles are audible is

described. Then, the computation of cumulative audibility of vehicles at different

distances from the road is presented. Finally, the calculation of average sound levels as a

function of distance is described. Appendix J presents more details on these

methodologies.

Background Sound Conditions and Terrain Characteristics

As described in Chapter III, Affected Environment, sound level measurements were

conducted at several locations throughout YNP and GTNP in February and March 2000.

These sound level measurements, supplemented by simultaneous audibility logging for

portions of the measurement periods, were used to establish the background sound

conditions for this analysis.

Based on the logging and observations made during site visits, hours during the day (8

A.M. to 6 P.M.) at each site were selected when intruding sound sources were likely to be

present less than 50% of the time. These selected hours became the set of hourly

statistical sound level data from which the background sound conditions were derived.

For the purposes of this analysis, two specific background sound level conditions were

identified for assessing impacts over the range of conditions: 1) the “average” condition,
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213

which includes the average effects of wind during the day; and 2) the “quiet” condition,

which represents times when winds are light or calm.

Also, as described in Chapter III, the analysis assumed that the A-weighted sound level

exceeded 90% (the L90) of each hour in which there were no or relatively few intrusions

would be the level used in the impact analysis for each alternative. Based on the site

characteristics and the measured sound level data, two categories of sites were assumed:

1) sites in mostly open or lightly forested areas (“open”); and 2) sites in moderately

forested to heavily forested areas (“forested”). The background sound levels in the open

areas were slightly lower than those in the forested areas, the difference being due to the

sound of wind in the trees.

The “average” background sound level in the open areas was 20 dBA; in forested areas, it

was 22 dBA. The “quiet” background sound level in the open areas was 15 dBA. In the

forested areas, the quiet sound level was 18 dBA.

Audibility of a sound depends upon the frequency content (spectrum) of that sound and

of the background sound. Sound spectra for each of the background conditions were thus

required. Spectra corresponding to the background A-levels cited above were taken from

tape recordings of the background sound environment made at each site during the

measurement program.

Wheeled and Oversnow Vehicle Sound Levels

Sound level projections start with reference noise emission levels, the maximum pass-by

sound level of an individual wheeled or oversnow vehicle at a reference distance, usually

50 feet. Table 62 shows the A-weighted reference pass-by emission levels at 50 feet for

the oversnow vehicles for the speeds used in the sound level projections. Table 62 also

shows the reference emission levels for the rubber-tired road vehicles (automobiles and

buses) used in the analysis (Menge 1998). The audibility and sound propagation models

require an analysis by frequency, so the one-third octave frequency band spectral values

corresponding to the A-weighted vehicle emission levels were obtained and incorporated

in the model.

Table 62. Reference wheeled and oversnow vehicle noise emission levels.

Vehicle Type Speed (mph) Emission Level at 50 Feet (dBA)

Snowmobile 40 74

Bombardier snowcoach 30 75

4-track conversion van snowcoach 30 69

Snowplane 28 90

Automobile and van 40 68

Bus 40 76
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The rate at which sound drops off with distance by frequency was taken from the FHWA

Traffic Noise Model’s (TNM’s) sound-propagation algorithms, using snow as a groundcover type. TNM also includes tree zones as an input type, which was used for the

moderately forested to heavily forested area analysis. The effect of trees is to reduce

propagating sound levels by 5 dB to 10 dB over longer distances. The losses are less for

low frequencies than for high frequencies. Most of the terrain throughout the study area

is rolling or nearly flat. For practical purposes, the modeling assumed flat terrain.

Audibility Analysis — Single Events

Audibility was computed for each of the wheeled and oversnow vehicle types based on

auditory signal detection calculations, which compare the computed vehicle sound levels

by frequency to the background sound levels by frequency. The metric of audibility is

called d' (d-prime). A threshold for audibility derived from field observations occurs

where 10 log d' = 7 dB (Fidell 1994). This threshold was used in this analysis. Appendix

M provides more details.

Audibility Analysis — Combined Effects of All Oversnow and Wheeled Vehicles

The next level of analysis combined all of the wheeled and/or oversnow vehicles

projected to be on each roadway segment for each study alternative for combined

audibility calculations. For Jackson Lake, a single path was assumed, essentially down

the middle of the lake in a north-south orientation, even though snowplanes and

snowmobiles are free to travel anywhere on the lake surface.

The distance to the limit of audibility for each segment was determined for the “average”

and “quiet” background conditions and for the appropriate proportion of open and

forested terrain for that segment. Appendix M contains tables of these distances for each

alternative. Also determined was the percentage of time any of the oversnow or wheeled

vehicles on a given roadway segment would be audible at different distances back.

Composite summaries of total area (acreage) of park land affected were computed by

multiplying the distance to audibility by the segment length. Appendix M provides more

details on these calculations.

The results that will be presented in Chapter IV include the acres of park land (by road

segment) where any wheeled or oversnow vehicle noise is audible for each alternative.

These results are for both the “average” and “quiet” background conditions and for three

categories of audibility: (1) audible any amount of time (“audible at all”); (2) audible for

10% of the time or more; and (3) audible for 50% of the time or more. These categories

were chosen as reasonable means of assessing impacts and comparing alternatives.

It is important to note that audibility does not mean the sound levels of the oversnow or

wheeled vehicles are necessarily high. Even if a oversnow vehicle would be barely

audible, not even to the extent of raising the overall A-weighted sound level, that acreage

would be counted.
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215

In the calculations, it was assumed that the number of wheeled and oversnow vehicles

would be evenly, but randomly, distributed during the day. In reality, for many of the

modeled road segments, there tends to be a concentration of vehicles over certain hours

based on the distance a site is from the major points of origin and destination. This

concentration applies to, for example, day trips by snowmobile or snowcoach tours to

Old Faithful, wheeled vehicles bringing people to the staging areas for these tours, and

snowplanes going out onto Jackson Lake for ice fishing. If this concentration were

modeled, the probable result would be increased acreage for the “audible at all” category

(concentration produces higher levels at any given time), but decreased acreage for the

other two categories because there would be more time when few or no vehicles passed

by.

Average Sound Level Analysis

To permit an evaluation of the average magnitude of the noise from wheeled and

oversnow vehicle traffic, computations of the hourly equivalent or “average” sound level

(Leq) over the day were performed. Levels were computed for each road segment at two

distances, 100 feet and 4,000 feet, and for both open and forested terrain.

These hourly Leq values do not have the background sound level added into them. Also,

they cannot be compared against the background levels to assess audibility, because Leq

represents a long-term average of both quiet and loud moments.

For example, if only a single snowmobile, with a maximum level of 70 dBA, passed by a

site 100 feet from a trail in an entire hour, the Leq for that hour at that site would be about

40 dBA to 45 dBA. If ten 70-dBA snowmobiles passed by instead of one, the Leq would

be about 50 dBA to 55 dBA.

The concentration of vehicles during certain periods of the day, discussed above, would

result in a modest increase in the hourly Leq during the heavy-use hours, but a much

greater reduction in Leq (possibly to zero) for those hours when very few or any vehicles

would pass by. Concentration of vehicles does not affect the reported average daylong

Leq values.

Cultural Resources

The assessment of impacts to cultural resources followed a three-step process:

1) Determining the area of potential effect of the proposed actions;

2) Identifying the cultural resources within the area of potential effect that are either listed in

or eligible for listing in the National Register of Historic Places; and

3) Assessing the extent and type of impacts the proposed actions may have upon cultural

resources.

Regulations and policies for cultural resource management underlie the analysis

determinations presented in the consequence discussions. A summary of this direction is

found in Appendix C.
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An impact on a cultural resource occurs if an action has the potential of altering in any

way the characteristics that qualify the resource for inclusion in the National Register. If

a proposed action diminishes the integrity of such characteristics, it is considered to have

an adverse effect. Impacts that may occur subsequent to or at a distance from the

location of a proposed action are also potential impacts of the action, and are considered

indirect effects.

Potential impacts are based on best professional judgment and have been developed

through discussions with staff from the NPS, the Wyoming, Montana, and Idaho State

Historic Preservation Offices, the Advisory Council on Historic Preservation, affiliated

American Indian tribes, and representatives of other state and local agencies and

organizations.

This plan will provide state and local agencies and the public with information on the

effects that the alternatives would have on cultural resources. It also describes the ways

in which significant effects, if any, would be mitigated.

Visitor Access and Circulation

Changes in how people access park attractions or resources (that is, the modes of

transportation they use and the activities they pursue) are evaluated. Potential access

changes may occur in alternatives that provide incentive for shifts in park access from

one entrance station to another or in alternatives that may potentially divert existing

visitors to other areas outside the park units.

In comments on the DEIS, cooperating agencies and others supported the inclusion of use

limitations. Specified use limits were not part of the DEIS. At the same time, they

expressed concern about how displaced snowmobile use would affect lands adjacent to

the parks. The DEIS included no quantitative predictions about use redistribution,

although it did discuss the subject qualitatively. In response to these comments, the NPS

determined that it needed to provide quantitative scenarios of the resulting use for each

alternative. It should be understood that the NPS cannot predict what will happen.

However, CEQ regulations (40 CFR §1502.22) allow NEPA processes to be completed

despite unavailable data. It allows the construction of reasonably foreseeable impact

scenarios upon which to proceed. Through comments on the DEIS, the NPS feels there

is sufficient demand through comments on the DEIS to engage in this approach.

A scenario is provided that shows a reasonably foreseeable distribution of current use in

each alternative. The scenarios are used for showing impacts on visitor access, and as

inputs for modeling or assessing possible impact on, or risks to, other resources such as

noise, air quality, and water.

Appendix J provides the calculations for each scenario. The basis for redistributing use

is the current average daily use on each road or motorized trail segment. Where this use

is not available under an alternative, it is considered to be displaced from that location.

Depending on the alternative, a percentage of displaced users are assumed to continue to
ASSUMPTIONS AND METHODOLOGIES FOR EVALUATING IMPACTS

217

snowmobile in the GYA parks, but distributed to other open gateway road segments.

From visitor use surveys, it is known that a percentage of all winter users go to various

destinations in YNP. These percentages are applied to the existing and displaced (or

redistributed) use on the open gateway road segments in each alternative. For

alternatives in which no segments are closed to oversnow motorized use, use remains at

levels described in current management.

Figures used in the calculations were derived from the following sources: entrance station

and visitor use statistics from Visitor Services Offices of Yellowstone and Grand Teton

National Park and the Parkway 1992-1999, interior road segments in YNP and GTNP

(Borrie et al. 1997; Littlejohn 1996; Duffield et al. 2000). Table 63 provides definitions

for evaluating potential impacts by duration and extent.

Table 63. Definition of impacts to visitor access and circulation.

Impact Category Definition

Negligible The impact to access is not measurable or perceptible. Trip characteristics or

access to desired destinations are not altered through implementation of the

alternative action.

Minor The impact to access is measurable or perceptible, and is limited to a

relatively small number of winter use visitors desiring access to a localized

area or attraction. However, access to the localized area or attraction can be

gained through alternative routes with little disruption of circulation patterns

or loss of winter use opportunities.

Moderate The impact to access is sufficient to cause a shift in circulation patterns and

trip making characteristics requiring a change in the provision of visitor

services at desired destination areas or the shifting of services to other

destination areas within the park units. The change is measurable and

perceptible but does not deny visitors access to specific park attractions.

Major The impact to access is substantial through the elimination of access to

specific park attractions. Implementation of the alternative action would

cause a loss of access to many current winter use visitors.

Visitor Experience

This assessment is based on visitor surveys of several different groups of respondents.

The first group includes data from surveys of winter visitors to the parks. The second

group includes surveys that examine the opinions of summer visitors and the local,

regional and national populations at large concerning winter use management. The third

set of surveys includes information from studies conducted by the states of Montana,

Idaho and Wyoming, and Teton County, Wyoming. Two indicators of impact level were

used in the analysis. First, the availability of the range of winter visitor opportunities was

determined for each alternative. Second, the range of opportunities available under each

alternative was compared with the satisfaction, importance and value that the various

survey respondents place on that particular experience or opportunity. Where the

opinions of different user groups diverge concerning a particular value they are identified

in the analysis.

Criteria that are used to gage visitor satisfaction in each alternative are:
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ENVIRONMENTAL CONSEQUENCES

218

• Opportunities for viewing wildlife;

• Opportunities for viewing scenery;

• The quality of the groomed or ungroomed snow surface;

• Safety (the safe behavior of others);

• Access to winter activities and experience;

• Opportunities for quiet and solitude; and

• Clean air.

These indicators of visitor satisfaction were derived from eight primary sources:

Littlejohn (1996); Friemund (1996); Borrie and Friemund (1997); Borrie et al. (1999),

Davenport (1999); and Duffield et al. (2000a. 2000b, and 2000c). Other winter use

surveys and assessments from Teton County, Wyoming and the states of Wyoming,

Montana and Idaho, and YNP and GTNP were used to validate the criteria. Please refer

to the Visitor Experience, Chapter III section for more detailed discussion of the survey

data used in this analysis. Table 64 includes definitions for impacts to visitor

experience.

Table 64. Definition of impacts to visitor experience.

Impact Category Definition

Negligible Little noticeable change in visitor experience.

Minor Changes desired experiences but without appreciably limiting or enhancing

critical characteristics of the experience.

Moderate Changes critical characteristics of the desired experience or reduces or

increases the number of participants.

Major Eliminates, detracts from or greatly enhances multiple critical

characteristics of the desired experience or greatly reduces or increases

participation.

Neutral An action that will create no change in the defined indicators of visitor

satisfaction or quality of park experience.

Regulations and policies for management of visitor activities underlie the analysis

determinations presented in the consequence discussions. A summary of this direction is

presented in Appendix C.

EFFECTS COMMON TO ALL ALTERNATIVES

Socioeconomics

Actions that affect park visitation levels can impact socioeconomics. If visitor use

capacities different than current use levels are enforced by reservations, permits, or

differential fees, there may be significant impacts on socioeconomics. At this time,

future visitor use capacity changes, if any, are unknown.

Wildlife

Effects of oversnow motorized sound. Animals may exhibit physiological and

behavioral responses to human-caused noise. Because physiological responses are

difficult to measure in the wild, Moberg (1987) recommended using outcome measures
EFFECTS COMMON TO ALL ALTERNATIVES

219

such as reproductive success and survivorship as indicators of noise-induced stress in

free-ranging animals. Most effects of sound are mild enough that they are never

detectable as changes in population size or growth (Bowles 1995). This fact

demonstrates to the ability of animals to tolerate unnatural noise. Ungulates in particular

are especially adaptable to predictable, repeated noise and, if good hiding cover is

available, they may show little change in habitat use or home range size (Eckstein et al.

1979; Edge et al. 1985). In general most wildlife species rarely respond with

uncontrolled, panic behaviors to noise that is not associated with danger (Bowles 1995).

Instead, most responses are subtle and short term.

It is the association of sound with danger that apparently dictates the degree of response.

Studies have shown that the range at which animals avoided traffic was about the range

at which they could detect traffic noise (Dorrance et al. 1975; Singer and Beattie 1986;

Gese et al. 1989). This finding suggests that traffic noise was meaningful through its

association with human activity. Repeated exposure without harassment increases

tolerance, thus decreasing response. Of course, at some point, there may be a trade-off

between the energy saving value of habituation and decreased wariness to potential

danger, such as high levels of traffic.

An analysis of the effects of sound on wildlife is implicit in the assessment of motorized

use for each alternative. It can be inferred that as the level, location, and type of

motorized use changes, so will the associated effects of motorized sound. An analysis of

how the natural soundscape is impacted by alternative is included in this chapter.

Natural Soundscape

Table 65 presents the computed distances to the limits of audibility of a single pass-by of

each vehicle type in the open and forested terrain conditions for both the “average” and

“quiet” background conditions.

The quieted oversnow vehicles, which were modeled in alternatives B and D, are shown

here for completeness. Likewise, a distinction is made for snowplanes, showing the

existing average pass-by level and the level if all snowplanes were held to the current 86

dB regulated level. Except for those distinctions, the results shown in Table 65 do not

differ among the alternatives because they are associated with single pass-by events. A

vehicle type of “group of 4 snowmobiles” is included because snowmobiles tend to travel

in groups, which is not so for the other vehicle types.

Because the distances to audibility limits are based on the unique frequency

characteristics of the sound sources, the background environments and the human

auditory system, comparisons of the A-weighted sound levels alone will not lead to an

understanding of differences. For example, the Bombardier snowcoach can be heard at

greater distances than the snowplane, which exhibits significantly higher A-weighted

sound levels. Most of the sound energy from the snowplane at 50 feet is in the mid-and

high frequencies, which become significantly reduced over long distances, whereas most
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

220

of the sound energy from the Bombardier snowcoach is in the lower frequencies, which

are much less attenuated by distance.

Table 65. Distances to limits of audibility for individual vehicle pass-bys in open and forested

terrain and in average and quiet background conditions.

Distance to Limit of Audibility (feet)

Open Terrain Forested Terrain

Vehicle Type

Noise

Emission

Condition

Maximum

50 ft

Pass-by

Level

(dBA)

Average

Background

Quiet

Background

Average

Background

Quiet

Background

Automobile Existing 68 2,180 2,330 1,130 1,200

Bus Existing 76 5,520 6,090 2,620 2,860

Snowmobile Existing 74 3,860 4,120 1,990 2,230

Group of 4 snowmobiles Existing 74 each 7,000 7,510 3,340 3,790

Bombardier Snowcoach Existing 75 8,560 9,690 3,860 4,230

4-Track Conversion Van SC Existing 69 2,030 2,200 1,110 1,210

Snowplane Existing 90 6,680 7,340 3,010 3,200

Snowmobile Quieted - 70 70 2,690 2,860 1,450 1,620

Group of 4 snowmobiles Quieted - 70 70 each 4,730 5,060 2,370 2,670

Bombardier Snowcoach Quieted - 70 70 5,440 6,160 2,540 2,780

4-Track Conversion Van SC Quieted - 70 69 2,030 2,200 1,110 1,210

Snowplane Regulated 86 86 4,550 4,950 2,190 2,320

Snowmobile Quieted - 60 60 2,150 2,260 1,160 1,290

Group of 4 snowmobiles Quieted - 60 60 each 3,790 3,990 1,920 2,150

Bombardier Snowcoach Quieted - 60 60 3,840 4,300 1,840 1,990

4-Track Conversion Van SC Quieted - 60 60 1,240 1,340 720 790

These distances were used to compute impacted acreage by road segment for three

categories of audibility: 1) audible any amount of time (“audible at all”); 2) audible for

10% of the time or more; and 3) audible for 50% of the time or more. See Appendix M

for details on the approach: tables are presented for each alternative in the discussions of

effects by alternative.

In those tables, the road segment from Moran Junction to the South Entrance of GTNP

contributes the greatest to the total acreage values for all three audibility categories. For

each alternative, amounts that remain almost constant for all of the alternatives. This

plowed road, which is mostly along open terrain, carries a great deal of wheeled-vehicle

traffic either passing through the park on US 26 or destined for Jackson Hole Airport or

park offices in Moose and Beaver Creek. This road segment also carries a smaller

amount of alternative-specific traffic destined for Flagg Ranch, Colter Bay, Teton Park

Road and ski trailheads in GTNP.

Another major contributor to the “audible at all” acreage and, to a lesser extent, “audible

10% or more” is the plowed road segment from Mammoth to the YNP Northeast
MITIGATION COMMON TO ALL ALTERNATIVES

221

Entrance, by far the longest of the modeled segments. Its contribution to the acreage

amounts also remains virtually unchanged across all of the alternatives.

Visitor Experience

Visitors who have physical disabilities would have improved access under all alternatives

as winter access action plans are implemented and barriers to facilities and programs are

removed. All facilities, such as warming huts, mass transit or snowmobile staging areas

and restrooms, proposed for construction or reconstruction, would comply with all

federal and NPS accessibility requirements.

MITIGATION COMMON TO ALL ALTERNATIVES

Water Resources Mitigation

• Best management practices would be used during the construction, reconstruction, or

winter plowing of trails and roads to prevent unnecessary vegetation removal, erosion, and

sedimentation.

• New sanitary facilities would be constructed in locations using advanced technologies that

would protect water resources.

• Separate winter-motorized trails from drainages to mitigate the routing of snowpack

contaminants into surface water.

• Any new or reconstructed winter use sanitary facilities would be constructed in locations

and with advanced technologies that would protect water resources.

• A focused monitoring program would reduce the uncertainty of impacts from oversnow

vehicles, and if necessary indicate best management practices that might be implemented.

Wildlife, Including Federally Protected Species and Species of Special

Concern

• All area closures to protect sensitive resources would be enforced through regular patrols

by NPS personnel.

• Monitoring of eagle populations to identify and protect nests would continue. The park

would continue to support the objectives of the Greater Yellowstone Bald Eagle

Management Plan.

• Monitoring of wolf populations would continue.

• Lynx surveys would occur to document the distribution and abundance of lynx in the parks,

and the parks will abide by the recommendations of the Lynx Conservation Assessment

Strategy. The presence of other carnivores will be documented.

• Monitoring of grizzly bear populations would continue in accordance with the Interagency

Grizzly Bear Management Guidelines and the parks’ bear management plans.

• Monitoring and protection of trumpeter swan habitats and nests would continue, including

the closure of nest sites, when warranted, to public access from February 1 to September

15.

• Monitoring of potential or known winter use conflicts would result in area closures if

necessary to protect wildlife habitat.

Cultural Resources

• Should the discovery of human remains, funerary objects, sacred objects, or objects of

cultural patrimony occur during construction, provisions outlined in the Native American

Graves Protection and Repatriation Act of 1990 (25 USC 3001) would be followed.

• Trails and trailheads would be sited to avoid adversely impacting known cultural resources,

including potential cultural landscapes. In addition the use of natural materials and colors
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ENVIRONMENTAL CONSEQUENCES

222

for all permanent signs erected would allow the signs to blend into their surroundings.

IMPACTS OF IMPLEMENTING ALTERNATIVE A — NO ACTION

Effects on the Socioeconomic Environment

Regional Economy. In 1996, the states of Montana, Idaho, and Wyoming had a

combined total economic output of about $109.5 billion and total full- and part-time

employment of about 1.5 million jobs. The much smaller five-county GYA in 1996 had

a total economic output of $5.7 billion and total employment of 97,000 jobs.

The no action alternative would not impose any management changes on winter use in

the parks that would restrict or change winter visitation from its current level and trends.

Minority and Low-Income Populations. Currently, about 11.9% of winter visitors to

the GYA report annual household incomes below $25,000. This figure is substantially

higher for winter recreationists who live within the GYA (25.1%), and lower for visitors

from outside the three-state area (5.2%). The racial composition of winter visitors is very

homogeneous with 99% of respondents classifying themselves as white.

Under the no action alternative the current distribution of income and racial composition

could be expected to remain unchanged.

Social Values. The general public has strongly held and divergent values and opinions

on public policy issues concerning winter management of YNP and GTNP. Respondents

to the 1999 winter visitor survey reported overall support for continued mechanized

winter access to YNP. About 67% of respondents to the survey either agreed or strongly

agreed with the statement “visitors should have the opportunity to have mechanized

winter access to YNP.” Over 61% of respondents also agreed with the statement “I am

concerned about the possible disturbance of YNP wildlife in the winter.”

Continuation of the current policies under the no action alternative would be in concert

with the majority support by current winter users for continued winter mechanized

access. On the other hand, as discussed in the chapter on the Affected Environment, the

existing winter access policy is not preferred by the public in the region or the nation.

Nonmarket Values. Impacts on benefits that visitors and others derive from YNP and

the GYA would result from any changes in park visitation levels, and the quality and

extent of changes in park management. The average nonmarket willingness to pay for a

winter trip to the national parks within the GYA is $91 per person.

Under the no action alternative, there would be no expected changes in park visitation

levels resulting from any NPS management changes. Therefore, no management-related

change in aggregate nonmarket values would be expected to occur.
IMPACTS OF IMPLEMENTING ALTERNATIVE A — NO ACTION

223

Conclusion

The no action alternative would continue current policies in place within the GYA parks.

No policy-related impacts on socioeconomics would result.

Effects on Air Quality and Public Health

Under alternative A winter use activities would continue at a level similar to current

conditions. As noted in Chapter III, a number of studies have been conducted in recent

years to characterize air quality on high snowmobile use days. Also, short-term air

quality analyses were performed by means of atmospheric dispersion modeling for

carbon monoxide (CO) and particulate matter (PM10) to assess the relative impacts of the

winter use alternatives, including alternative A, on ambient air quality in the GYA.

Table 13, Table 14, and Table 15 summarize the results of CO modeling for six locations

in the three parks for alternative A. Table 66 and Table 67 show the predicted maximum

1-hour average CO concentrations and the calculated maximum 8-hour average CO

concentrations, respectively. The percent contribution of each vehicle type to the

maximum CO concentrations also is provided in Table 68 for the six locations. As noted

in the Methodologies section, the maximum concentrations are based on a peak morning

hour of a high use winter day, which typically occurs during President’s Day weekend in

February.

Table 66. Maximum 1-hour average CO concentrations for alternative A.

Location

1-hr Maximum

Concentration

(w/o Background)

(ppm)

1-hr Maximum

Concentration

(w/background)

(ppm)

Change Relative

to Alternative A

(w/o Background)

(%)

West Yellowstone Entrance 29.20 32.20 N.A.

West Entrance to Madison Roadway 11.80 14.80

Old Faithful Staging Area 1.29 4.29

Flagg Ranch Staging Area 1.72 4.72

Flagg Ranch to Colter Bay Roadway 1.10 4.10

Mammoth to NE Entrance Roadway 0.30 3.30
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ENVIRONMENTAL CONSEQUENCES

224

Table 67. Maximum 8-hour average CO concentrations for alternative A.

Location

8-hr Maximum

Concentration

(w/o Background)

(ppm)

8-hr Maximum

Concentration

(w/Background)

(ppm)

Change

Relative to

Alternative A

(w/o Background)

(%)

West Yellowstone Entrance 13.74** 15.15** N.A.

West Entrance to Madison Roadway 5.55** 6.96**

Old Faithful Staging Area 0.21 1.62

Flagg Ranch Staging Area 0.29 1.69

Flagg Ranch to Colter Bay Roadway 0.52** 1.93**

Mammoth to NE Entrance Roadway 0.14** 1.55**

** Estimated from the modeled maximum 1-hour average concentration based on the persistence formula

 Ct2 = Ct1*(t1/t2)^0.365 (Cooper and Alley 1990).

As noted in Table 66 CO levels are highest at the West Entrance and along the West

Entrance to Madison road, where relatively large numbers of snowmobiles operate in

relatively small geographic areas. Although the maximum West Entrance 1-hour average

concentration is larger than the Montana 1-hour ambient air quality standard of 23.0 ppm

and the 8-hour average CO concentration is larger than the federal ambient air quality

standards of 9.0 ppm, this does not indicate that violations of the standards are predicted.

Violations of the standards are based on the second highest CO concentration measured,

while the model provides only the highest value. Although there are relatively large

numbers of snowmobiles at the two staging areas, modeled CO concentrations are

relatively low since the machines are spread out over a wider area. Finally, the

Mammoth to Northeast Entrance roadway exhibits the lowest CO concentrations.

Coincidentally, no snowmobiles or snowcoaches operate along this roadway.

Table 68. Vehicle contribution to CO concentrations for alternative A.

Contribution (%)

Location SM SC AM LT HT TB SV

West Yellowstone Entrance 97.9 2.0 0 0 0.1 0 0

West Entrance to Madison Roadway 98.6 1.4 0 0 0 0 0

Old Faithful Staging Area 98.1 1.9 0 0 0.1 0 0

Flagg Ranch Staging Area 72.2 1.2 7.9 15.8 0.1 0.1 2.7

Flagg Ranch to Colter Bay Roadway 49.8 0 12.8 31.8 0.3 0.2 5.1

Mammoth to NE Entrance Roadway 0 0 26.5 66.9 0.5 0 6.1

SM = snowmobile, SC = snowcoach, AM = automobile, LT = light truck, HT = heavy truck, TB = tour bus, SV = shuttle

van.

Table 69 and Table 70 provide corresponding model results for PM10 for the same

locations and conditions as those for CO. Like CO levels, predicted PM10 concentrations

are highest at the West Entrance. However, violations of the state and federal ambient air

quality standards of 150μg/m3 are not predicted by the 24-hour maximum predicted

concentrations.
IMPACTS OF IMPLEMENTING ALTERNATIVE A — NO ACTION

225

Table 69. Maximum 24-hour average PM10 concentrations for alternative A.

Location

24-hr Maximum

Concentration

(w/o Background)

(μg/m3)

24-hr Maximum

Concentration

(w/Background)

(μg/m3)

Change

Relative to

Alternative A

(w/o Background)

(%)

West Yellowstone Entrance 45.19** 68.19 N.A.

West Entrance to Madison Roadway 10.74** 33.74

Old Faithful Staging Area 0.64 5.64

Flagg Ranch Staging Area 0.63 5.63

Flagg Ranch to Colter Bay Roadway 0.95** 5.95

Mammoth to NE Entrance Roadway 0.32** 5.32

** Estimated from the modeled maximum 1-hour average concentration based on the persistence formula

Ct2 = Ct1*(t1/t2)^0.365 (Cooper and Alley 1990).

Table 70. Vehicle contribution to PM10 concentrations for alternative A.

Contribution (%)

Location SM SC AM LT HT TB SV

West Yellowstone Entrance 99.3 0.2 0 0 0.5 0 0

West Entrance to Madison Roadway 97.6 1.1 0 0 1.3 0 0

Old Faithful Staging Area 99.8 0 0 0 0.2 0 0

Flagg Ranch Staging Area 99.3 0 0 0 0.4 0.3 0

Flagg Ranch to Colter Bay Roadway 45.4 0 10.2 20.9 13.1 7.1 3.4

Mammoth to NE Entrance Roadway 0 0 22.5 46.6 26.7 0 4.2

SM = snowmobile, SC = snowcoach, AM = automobile, LT = light truck, HT = heavy truck, TB = tour bus, SV = shuttle

van.

Visibility

The visibility assessment indicates that under this alternative, vehicular emissions would

cause localized, perceptible, visibility impairment near the West Entrance and in the area

around Old Faithful and Flagg Ranch. The emissions along heavily used roadway

segments would also lead to localized, perceptible, visibility impairment under certain

viewing conditions.

Conclusion

Based on previous studies and the results of air dispersion modeling conducted for this

analysis, short-term, adverse impacts at the West Entrance would continue at times,

during high winter use days. In YNP the effects of wintertime wheeled-vehicle use on air

quality would continue to be negligible due to the limited number of automobiles and

buses operating in the park during the wintertime. Under this alternative, YNP would

continue to use bio-based fuels and lubricants in the park. Since the use of these products

produces fewer emissions than other types of fuels and lubricants, a minor reduction in

impacts to air quality and public health would be expected.
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ENVIRONMENTAL CONSEQUENCES

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Effects on Public Safety

Current public safety conditions for visitors and employees in all three park units are

identified in the Affected Environment section of this document. Under the no action

alternative motor vehicle accident rates (both snowmobile and wheeled) would continue

to increase as visitation in the three park areas increases. Accidents on the Continental

Divide Snowmobile Trail (CDST) would continue to occur, although infrequently (1

occurred in 1999). Because of the shared automobile/snowmobile travel corridor, safety

on this route would remain a concern. The poor condition of some groomed routes

would also continue to be a safety concern, particularly on the heavily used section from

the West Entrance to Madison Junction and south to Old Faithful.

Avalanche control activities would continue on YNP’s East Entrance road, at the Talus

Slope and Washburn Hot Springs (spring only) and in GTNP.

Information on snowmobile safety would continue to be provided by ISSA; however, the

average first-time visitor would have limited access to snowmobile safety information in

the parks.

Conclusion

Alternative A would result in minor adverse impacts to visitor safety along the road from

West Yellowstone to Old Faithful, and the CDST, and negligible adverse impacts on less

heavily traveled routes. These impacts would directly affect employees and visitors.

Safety concerns for the 3% of winter visitors who utilize the East Entrance will be minor

to moderate and adverse. For employees who conduct avalanche control on Sylvan Pass

(and other areas) impacts will continue to be minor to moderate and adverse.

Effects on Geothermal Features

Adverse impacts can occur to geothermal features when visitors have unregulated access

to geothermal basins. Park visitors can alter or damage geothermal resources by

traveling off trail or throwing objects into features. Under alternative A, minor adverse

impacts to geothermal resources in both front country and backcountry areas would

continue. Some actions, such as throwing objects into the features that block the flow of

water, would have major adverse impacts on individual resources. Because of the length

of time it takes for this sensitive resource to recover, most impacts would be long term.

Currently park personnel educate visitors and mark trails to mitigate adverse impacts on

geothermal resources.

The 1990 plan approved the construction of a warming hut at Norris Geyser Basin. The

addition of a warming hut would increase winter visitor use in this geothermal basin.

Increased visitation would have direct minor adverse effects on geothermal features.

Conclusion

Minor adverse long-term impacts to geothermal features located along groomed roads,

around destination areas, and in the backcountry would continue. Degradation to thermal
IMPACTS OF IMPLEMENTING ALTERNATIVE A — NO ACTION

227

features located in the Norris Geyser Basin would increase slightly when the warming

hut is built.

Effects on Water and Aquatic Resources

Pollutants that are emitted into the air are deposited on the ground or in the snowpack

where they either volatilize, percolate into soil materials, or remain stored in snow.

Pollutants that persistent in snowpacks or in soil materials can be washed into drainages

with snowmelt, or move through the soil into nearby surface water sources, or into

groundwater storage over time. Due to geology and topography, the most likely potential

pathway for pollutants in the three park units is from snowpack into surface water with

snowmelt, or into shallow groundwater reservoirs that enter surface drainages during late

summer and early fall.31 Pollutants present in surface waters are available for uptake by

aquatic resources such as vegetation, fish, amphibians, or others who ingest the affected

water. Pollutants that persist over time in the environment can be washed beyond the

source of impact, eventually to settle in sediments or other traps, or they can be trapped

fairly close to the source in wetland vegetation, bottom sediments, or by instream

structures (such as dams and wiers).

The following assessment focuses on sources of pollution, and potential pollutants,

relating to winter use – combustion products from motorized vehicles (see air resources)

– and their impacts on 1) water quality, and 2) water dependent or aquatic resources. The

discussion frames potential effects while the conclusion expresses a final analysis of

impact on the three park units.

Water Quality

Many different chemical compounds enter the environment from snowmobile emissions

but benzene, toluene, ethylbenzene, and xylenes (collectively known as BTEX); methyl

tertiary butyl ether (MTBE); and polycyclic aromatic hydrocarbons (PAHs) are widely

recognized as the most toxic of the organic compounds. At least two inorganic

compounds of potential concern, sulfate and ammonium, are also found in snowmobile

emissions (Hagemann and VanMouwerik 1999).

Information is available on issues related to emissions from personal watercraft (PWC)

that have 2-stroke engines and use fuel mixtures similar to those used in most

snowmobiles. CO and PM emissions from snowmobiles would be different from those

produced by PWC because of the colder operating temperatures and differences in the

exhaust systems. Reports by VanMouwerik and Hagemann (1999) and Hagemann and

VanMouwerik (1999) are the primary source of the following information.

 

31 Some people who commented on the draft EIS pointed out that the discussions of air and water seemed to

be confused. These sections are rewritten in the Final EIS. NPS wishes to make clear that there is a strong

relationship between airborne pollutants and water quality. A number of monitoring sites exist in the GYA

and in many places throughout the United States to monitor acid deposition on the ground from ambient air

pollution. The strict protocol for locating such sites in snow-dominated climates includes avoiding areas used

by snowmobiles or other motorized vehicles.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

228

Studies on emissions from PWC indicate that MTBE and PAHs are the two contaminants

most likely to degrade water quality from snowmobile emissions. These contaminants

are more likely than others to be found in water primarily due to their persistence in the

environment.

The contamination of lakes and reservoirs with MTBE and PAHs has been documented

where 2-stroke PWC and outboard motors are used (Metropolitan Water District of

Southern California 1998; Reuter et al. 1998; Mastran et al. 1994; Oris et al. 1998).

Recreational use of these watercraft has been identified as a primary cause of this

contamination. Because water quality degradation has been documented in association

with 2-stroke motor usage, it follows that water quality adjacent to areas of high

snowmobile use also could be degraded by MTBE and PAH.

It is not known whether or how much fuel used by oversnow vehicles in GTNP and YNP

has MTBE additives, however, MTBEs are not currently perceived to be an issue for the

parks. MTBEs are not used in fuels sold in Montana (Haines, pers. com., 2000).

Wyoming DEQ has no knowledge regarding whether or not MTBE is used in fuels

within the State of Wyoming (Potter, pers. com., 2000), however if it is, it would

probably be the result of acquiring fuels from refineries in areas where it is used, such as

Colorado. Some fuels in Idaho, particularly those obtained from refineries near Salt Lake

City, Utah do contain MTBEs; however, EPA has proposed a rulemaking to require the

nationwide elimination of MTBE as a fuel additive by the year 2003 (Viswanathan, pers.

com., 2000).

Deposition of airborne PAHs onto the ground is a commonly accepted phenomenon, and

deposition of PAHs in areas of high snowmobile use is expected. PAHs may also be

imparted to snowpack from the injection of tailpipe emissions into deep snow. Losses of

PAHs from the snowpack are minimal since degradation processes such as photooxidation and volatilization do not occur or are severely impeded (Boom and Marsalek

1988). St u di e s ha ve me a su r e d P AH s i n sno w f r o m ne a r b y a ut om o bi l e po l l u t i on an d o t h e r 

po i n ts ou r c e s ( E t t a l a eta l . 198 6;Vi sk a r ie ta l .19 97 ;G j e ssi nge ta l . 19 84) . PA Hsf r om 

ne a r by au t om ob i l ep ol l ut i onh a vea l sob e e nf oun d in su r f a c ewa t e r( Gj e ss i n g e t al .1 984 ) . I n

t h e St. Lawrence River in Canada, s pringtime concentrations of PAHs were “most likely

caused by snowmelt” from nearby urban, rural, and industrial areas (Pham et al. 1993).

Atmospheric PAHs deposited onto snow also were found in a karst groundwater system

during and after snowmelt (Simmleit and Herrmann 1986). The PAHs documented in

these studies are found in snowmobile emissions.

PAH molecules preferentially bind to organic matter in soil. One study found “an

essential part of the PAHs” in snowmelt drainage off of a highway to be retained in the

soil surface layer (Gjessing et al. 1984). However, the amount of PAH-contaminated

meltwater that will pass over soil is difficult to predict. Some deposition will occur

directly onto snow-covered bodies of water. PAH-contaminated soil particles could also

be carried with runoff meltwater into nearby water bodies whereby PAHs could
IMPACTS OF IMPLEMENTING ALTERNATIVE A — NO ACTION

229

contaminate water bodies by transferring from the soil particles to the water or by

accumulating as sediment. Some expect the possible effects of PAH-contaminated

sediments to be a more serious, but currently less understood, risk to aquatic life than

PAH-contaminated water. Finally, PAHs could also be transported to surface water

bodies via overland flow during a rain-on-snow event.

BTEX are quite volatile and do not tend to bind to soil or sediment particles (Irwin et al.

1998). Volatilization rates from snow are not reported in the literature but are expected

to be similar to those from water and soil surfaces that vary widely, ranging from less

than one minute to a few weeks. Most values reported fall within the range of a few

hours to a few days (Irwin et al. 1998). Given this, BTEX compounds are expected to

mostly evaporate before the spring melt arrives. However, it may also be possible that

BTEX emitted onto the snow from one snowmobile could become packed into the snow

by snowmobiles following immediately behind it, in effect trapping these compounds in

the snowpack until the spring melt. If this were the case, the amount of BTEX entering

an adjacent receiving water will be determined largely by volatilization processes during

the spring melt and the time and pathway taken to reach the water. This needs further

study. Where snowmobiles are operated directly over frozen bodies of water, the

chances of BTEX and other snowmobile contaminants entering the water are greater.

Sulfate in the snowpack associated with snowmobile use would be mobilized with the

onset of snowmelt (Ingersoll 1999; Ingersoll et al. 1997). Once sulfate reaches

groundwater or surface water, acidification is possible in alpine areas where buffering

potential is low because of thin soils and exposed rock (Corn and Vertucci 1992). Pulses

of acidity have been observed during spring snowmelt in lakes in the Rocky Mountains

(Corn and Vertucci 1992) and in southern Norway (Hagen and Langeland 1973). Water

bodies in the Rocky Mountains are thought to be influenced by point sources of

atmospheric pollution (Corn and Vertucci 1992; Ingersoll et al. 1997). Nearby lakes on

the Bridger-Teton and Shoshone National Forests, for example, are the most highly

susceptible lakes in the nation to acidification.

Aquatic Resources

According to EPA's Office of Mobile Sources, about 30% of the U.S. gasoline supply

currently contains oxygenates such as MTBE to improve air quality. These oxygenates

enhance octane level, increase burning efficiency, and reduce the emission of

atmospheric pollutants. MTBE is a suspected carcinogen (California EPA 1999b). There

is little known about the risk to aquatic organisms from MTBE, however one of the most

thorough studies to date found that there is little toxicity of MTBE to aquatic organisms

(Johnson 1998). The study found that adverse effects on rainbow trout are not expected

until concentrations of MTBE in the water column reach 4,600 to 4,700 μg/L. These

levels are much greater than the human health standards for MTBE in drinking water

supplies. Green algae have the lowest tolerance to MTBE but, according to this study,
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

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the results “indicate that there is low potential for adverse ecological effects from levels

of MTBE currently in surface waters.”

These studies indicate that the emission of MTBE from motor vehicles and incidental

spillage have the potential to contaminate water. This contamination is most acute in

lakes from the use of PWC where it is at levels that could pose a risk to human health.

However, because no sampling has been conducted in the areas of snowmobile use, there

is no evidence to conclude for certain that MTBE is present or, if present, if it is in

concentrations that would pose a risk to humans and aquatic organisms that consume or

contact water. The presence of MTBE and its potential risk in areas of snowmobile use

can only be determined through snow- and water-sampling studies.

PAHs (polycyclic aromatic hydrocarbons), which are found in snowmobile emissions

(White and Carroll 1998) are known carcinogens and are toxic to aquatic life. PAH

concentrations dangerous to human health are very low. The lowest water quality

standards for individual carcinogenic PAHs for the consumption of fish from a PAHcontaminated water body is 49 ng/L (parts per trillion), and for the consumption of both

fish and drinking water it is even lower at 4.4 ng/L (U.S. EPA 1998b).

PAHs have also been found to be toxic to aquatic life at very low concentrations due to

their phototoxic effects (Oris et al. 1998). PAH concentrations of 5-70 ng/L were toxic

to aquatic life, and calculated no-observed-effect-concentrations (NOEC) for PAHs were

only 3 ng/L, 7 ng/L, and 9 ng/L for zooplankton reproduction, zooplankton survival, and

fish growth, respectively (Oris et al. 1998). Another recent study, based on toxicity tests,

suggests a water quality standard for total PAHs of only 10 ng/L. This includes a safety

factor of about 100 times (Heintz et al. 1999). Levels of PAHs in excess of human health

standards and levels that could harm aquatic life have been found in lakes and reservoirs

where 2-stroke engines are used (Va nM ouw e r i k an d H a g e m a nn19 99 ) .

Adams (1975), found hydrocarbons in water and fish tissue as a result of snowmobile use

on a frozen pond surface in Maine. Though PAHs were not specifically measured, it is

quite possible they were part of the hydrocarbons found. Hydrocarbon concentrations

before and after the winter snowmobiling season increased from non-detect to 10 parts

per million ppm in water, and from non-detect to 1 ppm in fish tissue. These increases

were attributed to snowmobile emissions.

Referenced studies show that the emissions of PAHs from motorboats can contaminate

water and that PAHs from motor vehicles can contaminate snow. The PAHs from

motorboat pollution have been found at levels that pose a risk to aquatic life and human

health. However, because no sampling for PAHs has been conducted in the areas of

snowmobile use, it is not known whether they are present or, if present, if they are in

concentrations that would pose a risk to humans and aquatic organisms that consume or

contact water. Snow and water sampling studies are needed to determine the presence of

PAHs and their potential risk in areas of snowmobile use.
IMPACTS OF IMPLEMENTING ALTERNATIVE A — NO ACTION

231

BTEX (benzene, toluene, ethylbenzene, and xylenes) are much less persistent and

thought to be less of a water quality concern than PAHs, however preliminary and

extremely limited sampling in YNP found low levels of toluene in snowmelt waters

(Ingersoll 199). Additional monitoring and analyses are needed to verify those findings.

BTEX was also detected in the waters of Lake Tahoe, California; however,

concentrations were over 1,000 times lower than aquatic life protection levels, even

during periods of high motorboat (including PWC) activity (Allen et al. 1998).

No water sampling for sulfate has been conducted in the areas of snowmobile use;

therefore, it is not known if acidification is occurring. The presence of sulfate or

acidified waters and the potential for aquatic risk in areas of snowmobile use can only be

determined through snow- and water-sampling studies. During snowmelt intervals, the

rapid decreases in pH may pose a risk to amphibian embryos in breeding habitats in the

Rocky Mountains (Corn and Vertucci 1992).

Ammonium has also been found in snowpack in association with snowmobile use

(Ingersoll et al. 1997). In snow, it has been found to remain unchanged as ammonium

(USGS, Campbell, pers. com., 1999). It is thought to dissolve into meltwater where it

remains intact until it passes over soil or enters an oxygenated water body; at this point it

can be used by terrestrial flora or be converted to nitrate in soil or in the receiving water.

This could contribute to acidification, a decrease in dissolved oxygen, and eutrophication

of receiving waters (USGS, Campbell and Mueller, pers. com., 1999).

The potential effects summarized from the literature, above, are circumstantial, and point

to concerns about winter use. Specific to YNP, Ingersoll (1999) and Ingersoll et al.

(1997) found that concentrations of ammonium, sulfate, benzene, and toluene were

positively correlated with oversnow traffic in YNP. Where more snowmobile traffic

occurred near West Yellowstone, and Old Faithful, higher concentrations of the

pollutants were detected. At the lower-traffic locations near Lewis Lake Divide and

Sylvan Lake, lower concentrations were found. At the higher snowmobile-use locations,

in-road samples were substantially more concentrated than off-road samples.

Concentrations of ammonium and sulfate at the sites in the snowpacked roadways

between West Yellowstone and Old Faithful were greater than those observed at any of

the 50 to 60 other snowpack-sampling sites in the Rocky Mountain region. Results

indicate that snowmobile use along the routes originating at the South and East Entrances

may not be substantially affecting atmospheric deposition of ammonium, sulfate, and

hydrocarbons relating to gasoline combustion. Sample concentrations in snow collected

a distance of 50 meters or more off-road were similar to many lower, background levels

around YNP where minimal snowmobile use (if any) occurs.

Ingersoll (1999) concludes, from the analysis of five of the six snow sampling sites, that

elevated emission levels in snow along highway corridors generally are dispersed into

surrounding watersheds at concentrations below levels likely to threaten human or

ecosystem health. Localized, episodic acidification of aquatic ecosystems in these high
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

232

snowmobile traffic areas may be possible but verification will require more detailed

chemical analyses.

Given the possibility of impacts, it is appropriate as a guide to future monitoring to assess

risks. The methods section for water and aquatic resources explains the risk analysis.

Risk is predicated on pollutants sources (emissions), types of pollutants (toxicity and

persistence), amounts of pollutants, and proximity of the source to water. Sources

include emissions from oversnow vehicles and toxic and persistent pollutants (see Air

Quality methods and alternative analyses). Quantities of pollution are indexed to the

number of oversnow vehicle miles traveled along a segment, and segments are ranked

according to their proximity to surface water (and wetlands).

For the existing condition, the relative risks are conveyed in Table 71.

Five road segments totaling about 22% of the current oversnow route miles in YNP,

GTNP, and the Parkway (Madison to Norris, Canyon Village to Fishing Bridge, Madison

to Old Faithful, Grassy Lake Road, and Colter Bay to Moran Junction) are defined as a

“high” risk because more than 76% of each road segment is within 100 meters of rivers,

lakes, or other waters, thereby posing a higher potential or risk of pollutants entering

surface and subsurface waters.
IMPACTS OF IMPLEMENTING ALTERNATIVE A — NO ACTION

233

Table 7132. Relative risks considering current oversnow motorized use.

Impact: Daily Vehicle Miles Traveled Along

the Segment*

Road Segment

Risk ±

Rating SM SC

Mammoth to Northeast Entrance Medium 0 0

Mammoth to Norris Medium 641 69

West Entrance to Madison Medium 7759 127

Madison to Norris High 3458 73

Norris to Canyon Village Low 2214 47

Canyon Village to Fishing Bridge High 2370 50

Fishing Bridge to East Entrance Medium 983 0

Fishing Bridge to West Thumb Medium 2627 55

Madison to Old Faithful High 7818 165

Old Faithful to West Thumb Medium 3560 73

West Thumb to Flagg Ranch Medium 4219 103

Grassy Lake Road High 184 0

Flagg Ranch to Colter Bay Low 379 0

Colter Bay to Moran Junction High 248 0

Moran Junction to East Entrance Medium 49 0

Moran Junction to South Entrance Low 0 0

Teton Park Road Low 156 0

Moose-Wilson Road Low 6 0

Antelope Flats Snowmobile Route Low 0 0

Seven road segments totaling about 32% of the current oversnow routes (Mammoth to

Norris, West Entrance to Madison, Fishing Bridge to East Entrance, Fishing Bridge to

West Thumb, Old Faithful to West Thumb, West Thumb to Flagg Ranch, and Moran

Junction to East Entrance) are defined as a “medium” risk because 51% to 75% of each

road segment is within 100 meters of surface water or wetlands.

Four road segments totaling about 7% of the current oversnow routes (Norris to Canyon,

Flagg Ranch to Colter Bay, Teton Park Road, and Moose-Wilson Road) are defined as

posing a “low” risk because less than 50% of each road segment is within 100 meters of

surface water or wetlands.

 

32 *SM = Snowmobile, SC = Snowcoach; Vehicle-miles derived from visitor use scenarios shown in

Appendix J. The source of pollutants is emissions from snowmobiles, which produce (conservatively) 10

times as many emissions per mile as most wheeled vehicles. Single snowcoaches produce less emissions

then single snowmobiles.

±High = within 100 meters of rivers, lakes, or other waters for a significant portion (76% to 100%) of the

road segment; Medium = within 100 meters of rivers, lakes, other waters, or wetlands for a moderate portion

(51% to 75%) of the road segment; and Low= risk segments are within 100 meters of rivers, lakes, or other

waters less than 50% of the road segment.
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234

Three road segments (Mammoth to Northeast, Moran Junction to South Entrance, and

Antelope Flats Snowmobile Route) currently have no snowmobile traffic and therefore

have no impacts from snowmobile emissions.

Based on the literature summarized above, the use of snowmobiles and snowplanes

directly on the surface of Jackson Lake is likely causing the direct deposition of

hydrocarbons, MTBEs, and PAHs into lake water with ice and snowmelt. This has the

potential for a moderate to high adverse impact, as defined, although the effects of use to

date have not been measured.

Conclusion

Deposition into snowpack would continue to occur from 2-stroke engine emissions along

groomed park roads in YNP and GTNP. The effect of this deposition on water quality is

undetermined but there is currently no evidence of measurable changes in water quality

or effects on aquatic resources. Elevated emission levels in snow along highway

corridors generally are dispersed into surrounding watersheds at concentrations below

levels likely to threaten human or ecosystem health. Localized, episodic acidification of

aquatic ecosystems in these high snowmobile traffic areas may be possible but

verification will require more detailed chemical analyses.

Accumulations of pollutants in aquatic systems may have as yet unmeasured adverse

impacts on wetlands and aquatic resources downstream from high-risk road segments.

Continued oversnow vehicle use at current levels involves localized high risk to surface

water quality along 22% of the road segments in the three park units. Snowmobile and

snowplane use on Jackson Lake would continue the risk of moderate to major adverse

impacts on water quality in the lake. The continued use of bio-based fuels by the park

service and the availability of fuels in gateway communities may result in a minor

decrease in pollutant deposition into snow, but could significantly reduce the persistence

of emission products in aquatic systems.

Effects on Wildlife

General Effects

Winter recreation activities take place during the season when animals are stressed by

climate and food shortages. Disturbance or harassment of wildlife during this sensitive

time can have a negative effect on individual animals and, in some cases, populations as

a whole (Moen et al. 1982). The most critical times for wildlife involve cold weather,

late pregnancy, and other times when animals are in a state of negative energy balance

(Geist 1978). The consequences of human-caused wildlife disturbance include: elevation

of heart rate and metabolism; flight; displacement from habitats; reduced reproduction;

increased susceptibility to predation; and diminished health as a result of increased

energy costs (Moen et al. 1982; Geist 1978; Cassier et al. 1992; Picton 1999; Aune

1981). Thus, although animals may appear unaffected by human activities (Aune 1981),

adverse effects may nonetheless be occurring. In YNP’s Madison, Firehole, and Gibbon
IMPACTS OF IMPLEMENTING ALTERNATIVE A — NO ACTION

235

River valleys, Aune (1981) reported that wildlife developed crepuscular patterns in

response to winter recreation activity, were displaced from trailsides, and that their

movements were inhibited by traffic and snow berms created by plowing and grooming

operations.

Ream (1980) reviewed 232 publications on the impacts of recreation on wildlife, and

concluded that in general living near small numbers of nonaggressive humans did not

significantly impact wild animals. Recreationists, however, because of their numbers and

sometimes inappropriate behavior, were causing severe impacts because of harassment

and the habituation of particular species.

Ungulates

Effects of groomed roads and trails. Packed trails may influence wildlife movements

and distributions by facilitating travel into areas that would normally be inaccessible due

to deep snow. Under alternative A, YNP maintains 184 miles of groomed motorized

roads and 37 miles of groomed nonmotorized trails. GTNP (including the Parkway)

maintains 36 miles of groomed motorized surfaces.

As described in Chapter III, biologists agree that bison use groomed roads in winter to

travel to different foraging areas, but disagree as to the extent that they use roads or how

this use affects population dynamics (Meagher 1993; Meagher et al. 1994; Bjornlie and

Garrot 1998; Cheville et al. 1998; Kurz 1998; NPS 1998). A three-year monitoring

project (Kurz et al. 2000) and another research project (Bjornlie 2000) showed that only a

relatively small proportion of bison activity33 involved the use of groomed roads

(Bjornlie and Garrot 1998; Kurz 1998; Kurz et al. 2000; Bjornlie 2000). The amount of

use varied by year, and may be related to snow depth and population size. Furthermore,

bison use of roads was negatively correlated with road grooming, with peak periods of

road use occurring before and after the winter use season (Bjornlie 2000). Data also

indicated that bison were not using the groomed road surface for major shifts in

distribution (Bjornlie and Garrot 1998; Bjornlie 2000). Instead, the vast majority of

bison were described as traveling primarily along established game trails, geothermal

areas, and river corridors.

On the other hand, long-term studies of bison population dynamics, distribution, and

movements suggest that groomed roads have provided bison with increased access to

foraging areas, and have facilitated population expansion and shifts in distribution

(Meagher 1989; Meagher 1993; Meagher et al. 1994; Meagher 1998). Using the

groomed roads to travel to existing and new foraging habitats reduces the energy costs

relative to traveling through deep snow. Bison use of winter roads may have changed the

energetics of bison ecology by facilitating shifts in the distribution of wintering groups

 

33 An average of 7.6% of bison observations in the Hayden Valley study area were on the road during the

winters of 1997-98, 1998-99, and 1999-2000 (Kurz et al. 2000). Bjornlie (2000) reported use of groomed

roads to account for 17% of all observed travel in the Madison-Gibbon-Firehole area during the winters of

1997-98 and 1998-99.
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236

within the YNP population, increasing the overall abundance of bison in the park, and

leading to the dispersal of bison into new habitats within and outside YNP (Meagher

1993; Meagher et al. 1994).

In recent years, a number of bison have traveled from the preferred thermal habitats in

the north central portion of YNP to other areas of winter range within and outside of park

boundaries. Along the northern portion of YNP, bison may travel on ungroomed trails

(e.g., the Yellowstone River Trail), game trails, or over open terrain to and through

public lands outside YNP. They travel east of the Yellowstone River into the Eagle

Creek/Bear Creek area, or west of the river through open terrain in the Stephens Creek

area. Here they are currently prevented from moving onto private lands immediately

adjacent and north of the YNP boundary. Along YNP’s western boundary, bison may

move to lands outside the park in the Cougar Creek and Duck Creek areas or they may

travel along or near the Madison River to public lands in the Horse Butte area. Nearly all

bison movement to the west appears to occur on game trails, open terrain, or along the

Madison River, with the exception of a short section of road through the Madison

Canyon, where use peaks in the fall and spring. Bison use of groomed roads was

reported as highest in mid-winter (February – March) between Fountain Flats and Old

Faithful along the Firehole River (Bjornlie 2000). According to Bjornlie (2000), changes

in bison distribution and movement patterns over the past 30 years occurred as a result of

natural range expansion as the population increased from near extirpation and began to

use alternate foraging areas.

Elk, moose, and deer may also travel on groomed or packed routes (Tyers 1999; Aune

1981; Richens and Lavigne 1978). In one study, elk use of groomed routes in YNP

increased throughout the winter as snow became increasingly deeper and more crusted

and as animals’ conditions declined (Aune 1981). In another study, deer mobility

appeared to be enhanced by packed snowmobile trails during periods of deep snow in

Maine (Lavigne 1976). It is unknown if the energy saved by walking on groomed routes

is greater than the associated disturbance caused by traffic on these routes (Clark 1999).

Effects of motorized oversnow use of groomed and ungroomed roads and trails. The

use of motorized oversnow vehicles can cause injury and death to wildlife, especially in

poor lighting conditions and during snowfall, and displacement from preferred habitats.

Under alternative A, these effects are associated with about 184 miles of groomed road

surface in YNP and about 72 miles of groomed and ungroomed surfaces for motorized

use in GTNP and the Parkway. Although both snowmobiles and snowcoaches use these

routes, impacts are associated with the sound, speed, and number of snowmobiles —

there are no documented accounts of snowcoaches hitting and killing any large mammal

in the park (Gunther et al. 1998).

Over a 10-year period ending in 1998, 14 ungulates were killed by snowmobiles in YNP,

primarily between Madison Junction and the West Entrance (Gunther et al. 1998). Bison

were the most commonly hit (10), followed by elk (3), and moose (1). The majority of
IMPACTS OF IMPLEMENTING ALTERNATIVE A — NO ACTION

237

mortalities occurred in areas of ungulate winter range, thus alternatives for winter use

that increase vehicular traffic (oversnow or wheeled) in these areas would likely increase

the frequency of road-killed wildlife. There are no statistics that account for injuries or

increased energy expenditures that may eventually lead to mortality. Impacts, including

mortalities, related to oversnow motorized use are considered to be negligible relative to

the size of the ungulate population. Gunther et al. (1998) estimated that the annual

number of road-kills (for both oversnow and wheeled-vehicles) has been 1% or less of

each species’ total population.

Because moose instinctively stand their ground when faced with a perceived threat, they

may be especially vulnerable to collisions. Under alternative A, Highway 89/287 and the

Continental Divide Snowmobile Trail (CDST) would continue to intersect and parallel

riparian habitat between the Buffalo Fork, Snake River, and Willow Flats. Therefore,

collisions between moose and vehicles, although they involve a negligible percentage of

the moose population, would continue at the present rate along this stretch.

In YNP Aune (1981) observed that snowmobile-bison interactions increased with snow

depth. Although bison habituate to snowmobiles to some degree, when a response was

elicited, it most often resulted in the bison fleeing, with snowmobiles frequently herding

them down the packed trail. However, at the time of Aune’s 1981 study, bison

populations were increasing, so apparently disturbance and the extra energy expenditure

associated with it were not decreasing reproductive success (Cherry and Kratville 1999).

Bjornlie (2000) also observed bison responding to snowmobiles, and reported that 60%

of all bison groups observed traveling on groomed roads had negative reactions, most of

these reactions included running.

Displacement caused by human activities may be considered a form of habitat

fragmentation because it prevents animals from using parts of their home range. Because

elk are restricted to limited winter range where food and cover may be of marginal

quality, any human winter activity that could prevent the species from using all or part of

their winter range may have adverse effects on their ability to survive or successfully

reproduce (Clark 1999). Increased access into elk winter range as provided by plowed

and groomed roads may reduce the overall scale and effectiveness of elk habitat, and lead

to increased harassment and energetic stress (Picton 1999).

Dorrance et al. (1975) studied the responses of two white-tailed deer (Odocoileus

virginianus) herds, one that was habituated to snowmobile activity and one that was not.

Behavioral responses of the habituated herd were of short duration: deer fled from

snowmobiles but returned within several hours. Deer that were previously unexposed to

snowmobiles exhibited greater response, increasing the size of their home ranges and

becoming displaced from habitats near trails. Huff and Savage (1972) reported that

snowmobiling activity forced white-tailed deer into less preferred habitats, and Richens

and Lavigne (1978) found that snowmobiles moving at low speeds (<16 km/h) disturbed

white-tailed deer less than snowmobiles at higher speeds. However, when people
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ENVIRONMENTAL CONSEQUENCES

238

stopped to view deer, they elicited the greatest response, causing the deer to flush.

Although Aune (1981) observed many immediate behavioral responses to snowmobiles,

he did not determine that winter recreation was a major factor influencing wildlife

distribution, population or movement.

In the parks, bighorn sheep are not known to occupy winter habitats near oversnow

motorized routes. Consequently, the potential for displacement of sheep from key winter

range is not likely to occur as a result of snowmobile or snowcoach activity.

Effects of plowed roads. Road plowing may cause habitat fragmentation by creating

structural barriers (i.e., snow berms) to ungulate movements (Aune 1981). In addition

plowed roads, like groomed roads, may also provide an energy efficient mechanism for

wildlife movements, including bison, elk, and moose. Under alternative A, the effects

described above are associated with about 76 miles of plowed road in YNP, including US

Highway 191, a commercial 55 mph route linking the communities of West Yellowstone

and Bozeman, Montana. GTNP (including the Parkway) maintains about 100 miles of

plowed road.

Bison use plowed roads in a manner similar to groomed roads. In one study, 44% of

bison groups observed reacted negatively to wheeled-vehicles (Bjornlie 2000). Portions

of the plowed road between Old Faithful and West Yellowstone are used by a small

percentage of bison in the spring as they search for areas with early vegetation (Bjornlie

2000); on the north side of the park, bison travel down the highway from Tower over

Blacktail and down to Mammoth (Kurz, pers. com., 2000). This latter road intersects

winter range and has been plowed since the 1940s. The extent to which it influences

bison movements is unknown (Cherry and Kratville 1999).

Elk and moose also may travel on plowed routes. It is unknown if the energy saved by

walking on groomed routes is greater than the associated disturbance caused by traffic on

these routes. The snow berms associated with these routes may trap elk and other species

and increase their susceptibility to collisions with vehicles (Clark 1999). Given the large

size of the ungulate population in the parks relative to the number of animals that are

impacted by snow berms, the effect is considered minor.

Snow berms and guardrails may impede bighorn sheep movements in YNP (Caslick

1993), but intentional use of roads as travel corridors has not been documented.

Effects of motorized use of plowed roads. The effects of plowed roads are similar to

those of groomed roads, except that the magnitude of the effect is usually greater. The

use of motorized vehicles on plowed roads can cause displacement from preferred

habitats and injury and death for wildlife, especially in poor lighting conditions, at dusk

and dawn, and during snowfall.

As discussed above, displacement caused by human activities may be considered a form

of habitat fragmentation because it prevents animals from using parts of their home
IMPACTS OF IMPLEMENTING ALTERNATIVE A — NO ACTION

239

range. Because elk are restricted to limited winter range where food and cover may be of

marginal quality, any human winter activity that could prevent the species from using all

or part of their winter range may have adverse effects on their ability to survive or

successfully reproduce (Clark 1999). Increased access for humans into elk winter range

as provided by plowed and groomed roads may reduce the overall scale and effectiveness

of elk habitat and lead to increased harassment and energetic stress (Picton 1999).

Morgantini and Hudson (1979) reported that weather conditions combined with

harassment resulting from human activities associated with roads resulted in

displacement of elk to marginal foraging areas in Alberta. Impacts were especially acute

during severe winters when energy budgets were stressed.

During the winters from 1989-98, wheeled-vehicles accounted for 99% of all road-killed

large mammals (predominantly ungulates) in YNP. Of the 1,090 animals killed, elk

(427), mule deer (335) and bison (98) were the species most often involved in fatal

collisions (Gunther et al. 1998). The majority of the collisions occurred on U.S.

Highway 191, where both posted speed limits and actual speeds exceed those on the road

from the North Entrance to Cooke City. Overall, considering all species, the average

ratio of wheeled-vehicle road-kill mortality to snowmobile road-kill mortality was 17 to

1. Thus, alternatives that that change road use from snowmobiles to wheeled-vehicles

would likely result in an increase in road-killed animals. The use of mass transit and

enforcement of lower speed limits could ameliorate this effect.

In GTNP and the Parkway the CDST follows US Highway 89/287 from the eastern

boundary of GTNP near Moran Junction to Flagg Ranch (see Access and Circulation)

and parallels moose winter range in both the Buffalo Fork Valley and the northern edge

of Willow Flats. The proximity of the road and trail inhibits the movement of moose

within their winter range. Automobiles on the highway and snowmobiles on the trail

conflict with moose as they attempt to cross the trail and road. Moose are particularly

vulnerable to collisions with vehicles along this highway because the plowed road

provides relief from snow conditions as well as a travel corridor to foraging areas.

Moose use of this road in combination with their instinctive response of standing their

ground in the face of a perceived threat make them particularly vulnerable to vehicles

(Tyers 1998). Berms are constructed between the road and trail throughout the CDST to

prevent snowmobile versus automobile conflicts and, in many locations, the trail surface

is located substantially higher than the plowed highway. Therefore, moose using the

CDST that are forced to exit onto the plowed roadway have a considerable drop

(commonly greater than three feet) to negotiate. Occasional breaks are provided to allow

moose to avoid vehicles and exit the CDST. These measures are not always effective as

6 to 15 moose-vehicle collisions occur each year.

Under alternative A, Highway 89/287 and the CDST would continue to intersect and

parallel riparian habitat near the Buffalo Fork and Snake Rivers and Willow Flats.

Therefore, collisions between moose and vehicles, although they involve a negligible
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

240

percentage of the moose population, would continue at the present rate along this stretch

of highway.

In addition to mortality, wheeled-vehicles may also displace moose. In Denali National

Park, a 50% increase in vehicular traffic over ten years corresponded with a 72%

decrease in moose sightings along the main park road (Singer and Beattie 1986). In

YNP, GTNP, and the Parkway, however, there is no evidence that traffic is significantly

displacing moose.

In YNP the road between Gardiner, Montana and Mammoth, Wyoming intersects

bighorn sheep winter range. Although off-road public access is restricted, traffic may

disrupt sheep movement. Another affected area is sheep winter range between

Mammoth, Wyoming and Cooke City, Montana. Traffic on the plowed road disrupts

migration patterns and habitat use. In addition vehicles on both of these roads have killed

five bighorn sheep in a 10-year period (Gunther et al. 1998). In Alberta, bighorn sheep

subjected to predictable vehicular traffic exhibited few behavioral responses, thus sheep

may become habituated to repeated traffic (MacArthur et al. 1982).

Effects of nonmotorized use of groomed and designated ungroomed routes. The

primary effects of nonmotorized use on ungulates are displacement from preferred

habitats, especially geothermal areas that are important for winter survival in YNP, and

increased energy expenditures, including physiological stress, which may reduce

individuals’ chances of survival. These effects are believed to be of a greater magnitude

than those caused by motorized vehicles using established, predictable routes (Cole 1978;

Schultz and Bailey 1978; Walter 1978; Aune 1981; Cassier 1986). Under alternative A,

YNP maintains 37 miles of groomed nonmotorized trail, and with the exception of trails

in the Mammoth Hot Springs and Blacktail Plateau areas, routes are not located in areas

of high ungulate use. GTNP and the Parkway do not maintain groomed trails for

nonmotorized use, but do provide 26 miles of designated ungroomed routes for

nonmotorized use. These trails are not located in winter range.

Bison were found to respond noticeably to the presence of skiers who were off

established trails (Aune 1981). Like elk, bison apparently habituate to some degree to

repeated, predictable patterns of human activity on designated routes.

Elk are easily conditioned to predictable human activities, but tend to be disturbed by

deviations of normal patterns (Ward et al. 1973). Consequently, skiing may affect elk

behavior more than snowmobiling on established roads and trails (Aune 1981; Cassier et

al. 1992). Cassier et al. (1992) measured elk movements when disturbed by crosscountry skiers in YNP, and determined that the amount of winter range used by skiers

and the number of days involved were more important factors than skier numbers. They

recommended restricting skiers to more than 700 yards away from elk wintering areas to

minimize elk displacement on shrub-steppe and upland steppe winter ranges.
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241

In Alberta, elk moved away from heavily used ski trails, but skiing did not alter their

overall wintertime distribution (Ferguson and Keith 1982). Aune (1981) reported

snowmobiles on groomed roads resulted in an average elk flight distance of 38.8 meters,

compared to average flight distance of 53.5 meters from skiing. Studies conducted

outside the parks in Wyoming determined that elk preferred to be 0.5 miles distant from

recreationists, and therefore recommended that people concentration areas should be at

least this distance away from elk feeding sites (Ward et al. 1973)

Although moose are considered to be relatively tolerant of humans (Tyers 1999), winter

recreation, including cross-country skiing, has been documented as a cause in displacing

them (Rudd and Irwin 1985; Ferguson and Keith 1996). However, moose do habituate to

predictable human activities (Tyers 1999). Consequently, nonmotorized activities on

designated routes are considered to have negligible effects on moose.

The effects of skiing on bighorn sheep are restricted to the backcountry (i.e., nondesignated routes) and are described below.

Effects of unregulated backcountry nonmotorized use. Unregulated backcountry

nonmotorized use is more random and infrequent relative to nonmotorized use on

designated routes. Consequently, although encounters between backcountry users and

ungulates may only occur sporadically, they can be especially disturbing and lead to

additional energy expenditure and stress that reduces animals’ chances of survival and

reproduction. Overall, these effects are moderately disturbing, but short term.

The primary concern related to backcountry use and wildlife is effects on bighorn sheep.

Both YNP and GTNP have designated Sheep Management Closures to protect sheep

winter range. The closures in YNP encompass most bighorn winter range, and thus are

effective in minimizing disturbance related to winter recreation in that park. In GTNP

area closures at Static Peak and Kelly Flats would continue to protect some important

bighorn sheep winter range from disturbance caused by backcountry winter recreation

(i.e., skiing). However, under alternative A, other sheep winter ranges in GTNP would

remain open to public use.

Activities outside of established routes are more disruptive to ungulates than activities on

designated routes. Bison and elk were found to respond more quickly to skiers who were

off established trails than to skiers who were on designated routes (Aune 1981). Tyers

(1999) reported that moose in backcountry areas were more likely to run away from

skiers than were moose in front country areas where skiers were more commonly

encountered.

GTNP and the Wyoming Game and Fish Department are concerned with the impacts that

skiers and snowshoers may be having on moose and elk on Blacktail Butte, and on elk

and bison on Wolff Ridge (see Chapter III, Ungulate Winter Ranges). Specifically, these

activities may be displacing these ungulates, and incurring upon them additional
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energetic costs. Because alternative A does not restrict use of these areas, any potential

impacts would continue.

Effects of the presence and use of winter support facilities. Increases in human

activity associated with the presence of support facilities may displace species sensitive

to human disturbance. Under alternative A, a warming hut would be constructed at

Norris in the vicinity of ungulate winter range important to elk, deer, and bison.

Introducing winter human use into this area would reduce its habitat effectiveness by

potentially causing these species to be displaced to lower quality habitats. However, over

time, the predictable nature of the recreation expected to occur in the area may allow

these species to habituate to the increase in human activity.

Federally Protected Species

Effects of groomed roads and trails. Packed trails may influence wildlife movements

and distributions by facilitating travel for wildlife into areas that would normally be

inaccessible due to deep snow. Under alternative A, YNP maintains 184 miles of

groomed motorized roads and 37 miles of groomed nonmotorized trails. GTNP

maintains 36 miles of groomed motorized roads including the Parkway.

Groomed roads do not affect bald eagles or grizzly bears.

Groomed routes could affect wolf-prey interactions and habitat use (Thurber 1994;

Paquet et al. 1998). However, the ecological significance of altering natural movement

and foraging patterns is not fully known (Reinhart 1999). Furthermore, wolves in YNP

have not been documented to travel on groomed snowmobile routes (Smith, pers. com.,

2000).

Lynx may be affected by groomed routes because snow compaction may enable other

predators, especially coyotes, to compete in deep snow conditions where lynx would

otherwise have an advantage (Bider 1962; Ozoga and Harger 1966; Murray and Boutin

1991; Koehler and Aubry 1994; Murray et al. 1995; Lewis and Wenger 1998; Buskirk et

al. 1999). Increased competition may reduce the value of habitat for lynx, and may

exclude them altogether (USFS 1999). The degree to which packed trails may affect

interspecific competition among lynx and other predators is poorly understood (USFS

1999); no studies in the GYA exist that document this relationship. The rapid

recolonization of wolves to the parks may reduce coyote populations and consequently

reduce the risk of coyote competition with lynx (USFS 1999). The investigation of lynx

and lynx habitat use in the parks is a prerequisite to assessing impacts to lynx and is a

high priority for the NPS.
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243

Effects of motorized oversnow use of groomed and ungroomed roads and trails. The

use of motorized oversnow vehicles can cause displacement from preferred habitats.

Under alternative A, the effects described above are associated with about 184 miles of

groomed road surface in YNP (for both motorized and nonmotorized use) and about 72

miles of groomed and ungroomed surfaces for motorized use only in GTNP and the

Parkway. To date, no federally protected species have been killed by collisions with

snowmobiles or snowcoaches in the parks.

The primary effect of oversnow, motorized use on bald eagles is displacement of

foraging eagles, especially along river corridors (e.g., the Madison River from the West

Entrance to Madison Junction; the Firehole River to Old Faithful; the Gibbon River near

Norris; and the Yellowstone River from Fishing Bridge to Canyon). In GTNP and the

Parkway oversnow motorized traffic would not be expected to disturb eagles because the

travel corridor does not closely follow the Snake River. Disturbance to breeding eagles

would be minimal because eagle breeding activities initiate as winter activities begin to

decrease in the parks in late February (McEneaney, pers. com., 2000). Furthermore, only

one eagle nest is visible from the roadside in YNP and in GTNP under current park

policy, areas within a 0.5-mile radius around bald eagle nests on the Snake River are

closed to public access beginning February 15. Disturbance caused by snowmobiles on

the frozen surface of Jackson Lake would continue to cause only negligible impacts to

eagles because foraging and nesting activities would be minimal prior to the breakup of

the ice. In all park units, if monitoring indicates disturbance to bald eagles, additional

closures may be enacted.

Few data exist on the impacts of human activity on denning grizzly bears (Reinhart and

Tyers 1999). The following excerpt is from the Montana Chapter of the Wildlife

Society’s review of recreation impacts to denning grizzly bears (Claar et al. 1999):

Winter motorized recreation can be associated with defined routes or dispersed

over the landscape. Mace and Waller (1997) reported no den abandonment by

grizzly bears in the northern Swan Range, Montana, although they routinely observed

snowmobile activity within 2 km of grizzly bear dens. The den sites were usually

located on steep timbered slopes that the researchers believed were nearly impossible

for snowmobiles to traverse. However, Harding and Nagy (1980) reported den

abandonment due to hydrocarbon exploration activities in Northwest Territories,

Canada. Reynolds et al. (1986) reported on the responses of denning grizzly bears in

Alaska to winter seismic surveys, including snowmachines, drill rigs, aircraft, and

detonation of dynamite. Detonations within 0.8-1.2 miles of denning bears did not

cause abandonment, but movements within dens were noted in some cases. A female

with yearlings did not abandon her den when vehicle use was occurring within 325

feet. They reported probable den abandonment by an unmarked bear when seismic

activity was within 650 feet of the den. When vehicles operated within about 3,300

feet of denned bears, their heart rates were elevated compared to undisturbed
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244

conditions. The heart rate of denned bears increased in response to overflights by

small aircraft near the time of den emergence but not at other times.

Although abandonment of dens was not reported as a frequent result of the

winter human uses described, Reynolds and Hechtel (1980), Watts and Jonkel (1989)

and Mace and Waller (1997) expressed concern that the physiological stresses could

result in serious consequences to bears. Mace and Waller (1997) believed that the

greatest potential for disturbance from snowmobile activity occurs when females

with cubs are still confined to the den vicinity during spring and when bears descend

to lower elevations and more gentle terrain, which is more suitable to snowmobiling.

Any potential effects of recreation on denning bears are ameliorated because, in the

parks, preferred denning habitats are generally remote (Gunther, pers. comm.), and

snowmobiles are required to stay on designated routes.

Of greater concern are the effects of human activities that occur near important grizzly

bear foraging habitats during the pre- and post-denning period. Whether or not conflicts

occur is largely dependent upon the number of visitors in the parks, where recreational

activities occur, and the abundance and distribution of natural bear foods in any given

year. During years of high whitebark pine production, bears are not as likely to come

into conflict with human activities prior to denning because this food source occurs at

high elevations in remote, less visited areas. Most bear management actions occur in the

early to mid-fall, prior to the initiation of the winter use season, when the whitebark pine

seed crop has failed and bears seek out human sources of food, including garbage

(Gunther, pers. comm.). Park policy currently calls for closing areas of high bear use at

any time to reduce the risk of bear-human conflicts.

The likelihood of visitors encountering grizzly bears in the initial weeks of the winter use

season (mid- to late December) is extremely small as the vast majority of bears (about

96%) have denned by the second week of December (Haroldson et al. in prep). To date,

no conflicts have occurred during this period (Gunther, pers. com., 2000).

Winter activities in late February and March may conflict with emerged male grizzly

bears, 31% of which are out of their dens by March 15 (Haroldson et al. in prep). In

particular, activities in ungulate winter range may disturb grizzly bears feeding on

winter-killed carcasses. In YNP ungulate winter range includes geothermally influenced

areas in the Firehole, Gibbon, and Norris vicinities where the potential for human-bear

conflict in the spring is high (Reinhart and Tyers 1999).

To date, only one bear-human conflict has occurred prior to April in the parks (Gunther,

pers. com., 2000; Cain, pers. com., 2000). According to YNP’s Bear Management Area

Program, many important grizzly bear spring foraging areas are closed to the public

beginning March 15 to reduce displacement of bears and bear-human conflicts. For

example, the Old Faithful area, where bears graze on thermally influenced spring
IMPACTS OF IMPLEMENTING ALTERNATIVE A — NO ACTION

245

vegetation and scavenge winter-killed carcasses, is closed from the third Sunday in

March through April 14. From April 14 through Memorial Day weekend at the end of

May, 20,670 acres of the most important ungulate winter range in the area remains closed

to all recreational use. Consequently, grizzly bears have undisturbed use of most winterkilled ungulate carcasses in the Old Faithful area during the entire spring season.

Furthermore, before opening areas to the public, winter-killed carcasses that remain

within the developed area boundaries or within 100 yards of open roads are moved to

areas away from human activity. With the exception of the road from Mammoth to

Cooke City, other roads within YNP are closed to public entry by March 15 (latest

closing date), and most roads will remain closed to all public vehicles until at least April

15 (earliest opening date).

Impacts associated with the use of motorized oversnow vehicles on gray wolves are

related to disturbance. Wolves have been documented to avoid areas of snowmobile

activity thus becoming permanently displaced from some habitats (Carbyn 1974; NPS

1996); however, wolves in YNP have not been documented to travel on groomed

snowmobile routes (Smith, pers. comm.). Wolves do use areas near groomed

snowmobile roads in ungulate winter range, and in 1997, a pack was displaced from an

elk carcass by snowmobiles (Smith 1998). In GTNP continued snowmobile use in the

Antelope Flats and Ditch Creek areas could cause some disturbance to wolves due to

noise and human activity. However, snowmobiles are required to stay on designated

routes, preventing random use of the area.

Impacts to denning wolves would not be expected to occur because wolves den in April,

after the closure of the winter recreation season in the parks. In accordance with park

policy, areas within a 1-mile radius of the dens are closed to public entry in YNP; GTNP

also has the authority to enact closures. In addition in YNP, many of the wolf dens are

within grizzly bear spring closure areas, and thus are not subjected to disturbance from

humans.

Motorized routes pass through potential lynx habitat in the parks. Assessing the degree

of impacts to lynx in the parks is speculative because very little is known about lynx

distribution and abundance. Motorized oversnow recreation may affect lynx by

fragmenting habitat, reducing the effectiveness of intact habitat, causing displacement

from or avoidance of habitat, and creating added energetic stress (Halfpenny et al. 1999).

Impacts to breeding lynx would not be expected to occur because the winter recreation

season ends prior to the initiation of the breeding season.

Effects of plowed roads. Road plowing may cause habitat fragmentation by creating

structural barriers (i.e., snow berms) to wildlife movements (Aune 1981). In addition

similar to groomed roads, plowed roads may influence wildlife movements and

distributions by facilitating travel into areas that would normally be inaccessible due to

deep snow. Under alternative A, the effects described above are associated with about 76

miles of plowed road in YNP, including US Highway 191, a commercial 55 mph route
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linking the communities of West Yellowstone and Bozeman, Montana. GTNP, including

the Parkway, maintains about 100 miles of plowed road.

Plowed roads do not affect bald eagles.

The current winter season in YNP occurs from mid-December to mid-March. The

majority of bears have denned prior to the beginning of the winter season. Consequently,

plowed roads are not expected to affect grizzly bears. See Effects of motorized use of

groomed and ungroomed roads and trails for additional information on grizzly bears and

winter use.

Similar to the effects of groomed roads, plowed roads could potentially affect wolf-prey

interactions and habitat use (see Effects of groomed roads and trails). However, wolves

in the parks have not been documented to use plowed roads as travel corridors (Smith,

pers. comm.).

Lynx have been documented to travel along roadways providing that adequate cover is

available on both sides of the road (Koehler and Brittell 1990). Any vegetative cover

along plowed roadsides in the parks is generally buried under the snow; consequently, it

is doubtful that lynx, which require cover for security and for stalking prey (Koehler

1990), would use these roads as travel corridors. Most impacts associated with roads are

related to traffic volumes and are discussed below.

Effects of motorized use of plowed roads. The effects of traffic on plowed roads are

similar to those of traffic on groomed roads, except that the magnitude of the effect is

usually greater. The use of motorized vehicles on plowed roads can cause injury and

death for wildlife, especially in poor lighting conditions, at dusk and dawn, and during

snowfall, and can cause displacement from preferred habitats.

Motorized vehicles may strike bald eagles foraging on carcasses along roadsides, in

particular wheeled-vehicles on Highway 191 and on the road from Mammoth to Cooke

City. To date, only one bald eagle mortality has been attributed to a vehicle; it was hit on

Highway 191 on the northwest side of YNP (McEneaney, pers. comm.). Park policy

requires that carcasses on and along roads be routinely removed to avoid attracting bald

eagles and other scavengers. Eagles may also be displaced from perches by traffic on

these road segments, although such displacement is considered minor and short term due

to the fidelity bald eagles have to their traditional perches (McEneaney, pers. comm.).

Chronic disturbance, may, however, ultimately cause bald eagles to abandon their perch

sites (Cain, pers. comm.). No evidence exists, however, to suggest that bald eagles are

being chronically disturbed in the parks.

Although grizzly bears generally avoid road corridors (Reinhart and Tyers 1999), bears

may be attracted to carrion found along or near roads during the pre- and post-denning

period, thereby making them vulnerable to collisions with wheeled-vehicles. During a

10-year period, wheeled-vehicles killed two grizzly bears during the winter use season
IMPACTS OF IMPLEMENTING ALTERNATIVE A — NO ACTION

247

(Gunther et al. 1998). Displacement is not likely to occur because the majority of bears

have denned during this time. See Effects of motorized use of groomed and ungroomed

roads and trails for additional information regarding grizzly bear activity and winter

recreation.

From 1995-98, vehicles killed six wolves during the winter use season in YNP (Gunther

et al. 1998). In general, wolves avoid roads that are open to the public, but have been

documented to use closed or limited use roads (Thurber et al. 1994; Carbyn 1974). In

YNP wolves cross roads periodically, but little use of roads as travel corridors has been

documented (Smith, pers. comm.). The likelihood of wolves being hit by automobiles is

highest for those packs that inhabit areas on the north side of YNP, and to a lesser degree,

packs in GTNP.

Although a possibility, there are few records of lynx being killed on highways (USFS

1999) and no road-killed lynx have been documented in the GYA (Halfpenny et al.

1999). Carnivore research in Canada suggests that traffic volumes of 2,000 to 3,000

vehicles a day are problematic in terms of lynx being killed on highways (USFS 1999).

Winter traffic levels in the parks do not approach this volume. Other effects of wheeledmotorized traffic on lynx are similar to the effects of oversnow motorized traffic. Both

may displace individual lynx or cause them to avoid certain habitats. Wheeled-vehicles

can also impact hare abundance and activity at night, thereby affecting an important food

source for lynx.

Fragmentation of potential lynx habitat would continue to occur under alternative A

because several road sections in the parks intercept lynx habitat. In YNP the effects are

limited to US Highway 191 along the western boundary of the park. In GTNP US

Highway 89/287 from Moran Junction to Flagg Ranch intercepts potential lynx habitat.

Effects of nonmotorized use on groomed and designated ungroomed routes. The

primary effects of nonmotorized use on wildlife are displacement from preferred habitats

and increased energy expenditures, including physiological stress, which may reduce

individuals’ chances of survival. These effects are believed to be greater than those

caused by motorized vehicles using established, predictable routes (Cole 1978; Schultz

and Bailey 1978; Walter 1978; Aune 1981; Cassier 1986). In addition packed ski trails

may influence wildlife movements and distributions by allowing access to areas outside

of their normal range. Under alternative A, YNP maintains 37 miles of groomed

nonmotorized trail. GTNP and the Parkway do not maintain groomed trails for

nonmotorized use, but do provide 26 miles of designated ungroomed routes for

nonmotorized use. The area affected by nonmotorized trails in the parks is very small

relative to the total area of the park units. Minor site-specific impacts are possible where

trails occur in or near nesting sites or foraging areas. Nonmotorized uses of groomed and

ungroomed routes occur primarily where vehicular access permits easy access.
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In contrast to motorized activities, nonmotorized recreation (e.g., cross-country skiing),

especially when it occurs outside of predictable use areas or in riparian areas, may be

highly disruptive to bald eagles (Harmata and Oakleaf 1992; Grubb and King 1991;

Stalmaster and Newman 1978; McGarigal et al. 1991; Stangl 1994). In YNP this

includes areas along the Firehole, Madison, Yellowstone, and Lewis Rivers. In GTNP

the most important bald eagle wintering area, the Snake River floodplain, is entirely

closed to public access in the winter. Although recreational activities may occasionally

displace eagles from perches, the displacement is considered negligible and short term

due to the fidelity bald eagles have to their traditional perches (McEneaney, pers. com.,

2000). Chronic disturbance, may, however, ultimately cause bald eagles to abandon their

perch sites (Cain, pers. com., 2000). No evidence exists to suggest that bald eagles are

chronically disturbed in the parks. In all park units, if monitoring indicates disturbance to

bald eagles, additional closures may be enacted. Furthermore, disturbance to breeding

eagles would be minimal because eagle breeding activities initiate as winter activities

begin to decrease in the parks in late February. Under current park policy, areas within a

0.5 mile radius around bald eagle nests on the Snake River are closed to public access

beginning February 15.

Nonmotorized recreation is not likely to adversely affect grizzly bears because the

majority of bears have denned during the period of winter use. See Effects of motorized

use of groomed and ungroomed roads and trails for additional information regarding

grizzly bear activity and winter recreation.

Nonmotorized groomed trails pass through wolf winter range in YNP and could

negatively affect predator-prey relationships. To date in YNP, this has not been

documented to occur. In GTNP wolf activity in the winter is sporadic, and generally

focused in areas of relatively low human use.

Front country nonmotorized activities may occur in potential lynx habitat. Because the

abundance and distribution of lynx in the parks is unknown, it is difficult to assess the

impact of these activities. The majority of skiers in the parks remain on groomed routes,

therefore use is largely predictable. With the exception of human activity near den sites,

many researchers believe that lynx may be relatively tolerant of humans (USFS 1999).

Bowles (1995) reported that lynx may adapt to some level of human activity, and other

researchers documented lynx use of ski areas and winter construction camps in Colorado

(Halfpenny et al. 1982; Thompson 1987; Thompson and Halfpenny 1989 and 1991).

Minimizing disturbance to denning habitat is important from May to August (USFS

1999); consequently, winter recreation in the parks will not affect denning lynx.

Effects of unregulated backcountry nonmotorized use. Unregulated backcountry

nonmotorized use is more random and infrequent relative to nonmotorized use on

designated routes. Consequently, although encounters between backcountry users and

federally protected wildlife species may only occur sporadically, they may cause
IMPACTS OF IMPLEMENTING ALTERNATIVE A — NO ACTION

249

displacement and additional energy expenditure and stress that reduces animals’ chances

of survival and reproduction.

The effects of nonmotorized recreation in backcountry areas on bald eagles would likely

be greater than those on designated routes in the front country (Harmata and Oakleaf

1992; Grubb and King 1991; Stalmaster and Newman 1978; McGarigal et al. 1991;

Stangl 1994). Nonetheless, the effects of current winter use on eagles are not considered

a major concern in the parks (McEneaney, pers. com., 2000). See Effects of

nonmotorized use on groomed and designated ungroomed routes for a discussion of

nonmotorized activities and bald eagles.

Nonmotorized recreation in high-elevation backcountry areas frequented by grizzly bears

immediately before and after denning may potentially result in bear-human conflicts.

Conflicts may result in management actions taken against individual bears, including

translocation (most commonly) and lethal control (rarely). By mid-December the

majority of bears have denned, therefore the chance of backcountry skiers encountering

bears is low. Likewise, although some bears will be out of their dens during the first two

weeks of March, the odds of bear-human interactions are minimal.

Impacts to bears are more likely to occur prior to and following the winter use season as

bears seek out feeding opportunities. Backcountry recreation at these times may lead to

conflicts, potentially resulting in management actions taken against individual bears

including translocation and lethal control. Management actions may also occur as a

result of human-caused displacement of grizzly bears, or when bears seek food attractants

at park developments during years of low natural food availability (primarily whitebark

pine seeds). Similarly, displaced bears may be attracted to park developments and other

sources of human food. Current Bear Management Area restrictions (see Effects of

motorized use of groomed and ungroomed roads and trails) serve to minimize bearhuman confrontations in spring.

Nonmotorized groomed trails pass through wolf winter range in YNP and could

negatively affect predator-prey relationships. To date in YNP, this has not occurred. In

GTNP wolf activity in the winter is sporadic, and generally focused in areas of relatively

low human use.

Nonmotorized, backcountry recreation may affect lynx because disturbance is dispersed

and unpredictable (Schultz and Bailey 1978; Gabrielson and Smith 1995). With the

exception of habitat that is intercepted by roads, the majority of potential lynx habitat

occurs in the backcountry and takes considerable effort to access. Consequently, the

number of skiers potentially present in most lynx habitat in the winter is expected to be

low and their odds of encountering or displacing lynx is small. Regardless, restrictions

on backcountry use may be implemented at anytime to protect important lynx habitat.

Presence and use of winter support facilities. Warming huts and campgrounds can

cause habituation in some wildlife species due to the presence of human food and
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garbage, and can subsequently lead to human-wildlife conflicts. In addition increases in

human activity associated with the presence of support facilities may displace species

sensitive to human disturbance. Effects of such disturbance would be the same as those

previously discussed. Under alternative A, a warming hut would be constructed at

Norris.

Winter support facilities in the parks are not known to affect bald eagles.

A major problem associated with human development in occupied bear habitat is the

availability of food attractants. Bears that become conditioned to human foods and

garbage are often the targets of management actions, including lethal control. High

winter visitor use has contributed to a garbage problem in YNP. Garbage that has

accumulated throughout the winter may attract hungry grizzly bears in the spring. To

date, YNP does not have adequate winter garbage storage facilities but will rectify this

issue by constructing a winter garbage storage facility that is wildlife-proof in the Old

Faithful, Grant, Lake, and Canyon areas. This is a feature of all alternatives.

In YNP the construction of a warming hut at Norris will likely lead to an increase in

human activity in the surrounding area. Because the hut will be located in thermally

influenced ungulate winter range, any associated increase in human use could affect the

availability of bison and elk carcass, which provide important spring foods for grizzly

bears. Because ungulates have been known to habituate to predictable human activities

any displacement would most likely be short term. In addition as stated previously, the

majority of bears do not emerge from hibernation until after the winter use season at

which time the Bear Management Area restrictions will be in affect to allow bears

uninterrupted use of spring carcass habitats in known winter ranges. Areas of high bear

use may be closed at any time according to park policy.

Wolves may be affected in the short term by ungulate displacement in the Norris area.

The increase in human use expected in the Norris area as a result of the new warming hut

is not expected to affect lynx because the hut is outside of potential lynx habitat.

Species of Special Concern.

Effects of groomed roads and trails. Packed trails may influence wildlife movements

and distributions by facilitating travel into areas that would normally be inaccessible due

to deep snow; inhibit foraging activities of carnivores that tunnel beneath the snow to

hunt subnivian prey; and, reduce subnivian prey availability by increasing mortality of

these small mammals. Under alternative A, YNP maintains 184 miles of groomed

motorized roads and 37 miles of groomed nonmotorized trails. GTNP maintains 36 miles

of groomed motorized roads including the Parkway.

Because so few studies of wolverine ecology exist, it is unknown if wolverines would use

groomed routes. Because wolverines are considered especially sensitive to human

disturbance (Copeland 1996), it is unlikely that they would use routes frequently traveled
IMPACTS OF IMPLEMENTING ALTERNATIVE A — NO ACTION

251

by humans. The maintenance of the Sylvan Pass groomed route requires periodic

blasting to alleviate the risk of avalanches. This practice may affect wolverines and

wolverine habitat in the Sylvan Pass area.

The scarcity of fisher sightings in the parks and the paucity of studies on this species

inhibit an assessment of the impacts of winter use. They are known to travel on packed

snowshoe hare trails or reuse their own trails when snow is deep (Trochta 1999);

consequently, the potential exists for fishers to use groomed routes. However, the fisher

has been described as a species that typically avoids humans (Powell and Zielinski 1994);

thus, it may be inferred that they would not frequent these routes very often due to their

associated high levels of human activity.

American marten tunnel beneath the snow to prey upon small mammals. Raine (1983)

found that martens hunted beneath the snow less often when it was crusty and

compacted. Furthermore, prey may be less available in these areas as a result of

displacement and increased mortality caused by compaction (Trochta 1999). Martens

reportedly use packed snow trails created by other animals to conserve energy (Strickland

and Douglas 1987); therefore, it may be inferred that they may also use groomed trails to

some extent.

River otters closely associated with aquatic and riparian habitats seldom venture far from

water, and otter would not be expected to make use of groomed routes. Indirect effects to

otters related to the impact of motorized oversnow recreation on the aquatic environment

are discussed below.

Impacts on trumpeter swans are associated with motorized traffic on groomed routes

(discussed below), and not the routes themselves.

Sagebrush lizards hibernate throughout the winter use season but may be impacted by

winter activities that disturb rocky, geothermal areas. Groomed routes would not affect

sagebrush lizards because they are restricted to the road footprint and consequently do

not alter the rocky substrates preferred by this species.

Impacts on rubber boas, fish, and amphibians are limited to activities that affect the

aquatic environment. In regards to winter use, these impacts are limited to the use of

motorized oversnow recreation.

Effects of motorized oversnow use of groomed and ungroomed roads and trails. The

most likely impacts on species of special concern in the parks are displacement from

preferred habitats and degradation of the aquatic environment from pollutants in the

snowpack. Documented mortality caused by collisions with oversnow vehicles in the

parks is rare. In ten years only one of these species (a marten) was reportedly killed by a

snowmobile in YNP (Gunther et al. 1998). Under alternative A, the effects described

above are associated with about 184 miles of groomed road surface in YNP and about 72

miles of groomed and ungroomed surfaces for motorized use in GTNP and the Parkway.
CHAPTER IV

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252

Habitat displacement of wolverines has been documented to occur outside the parks, with

wolverines rarely using parts of their home range bisected by roads (Arthur et al. 1989;

Copeland 1996; Gunther et al. 1997 and 1999). It is unknown whether wolverines use or

are affected by groomed roads in the parks.

Because there is a chance that fishers, if they exist in the parks, may use groomed routes,

the possibility for fishers to be affected by traffic on these routes also exists. However,

the fisher has been described as a species that typically avoids humans (Powell and

Zielinski 1994). Thus, it may be inferred that they generally avoid these routes due to

their associated high levels of human activity. Impacts associated with displacement

would be negligible because vast areas exist in the parks that are off-limits to

snowmobile and snowcoach use.

American martens may be displaced by snowmobile and snowcoach activities, but

similar to fishers, the impact would be negligible because vast areas exist in the parks

that are off limits to snowmobile and snowcoach use.

Species that are associated with aquatic habitats (river otters, fish, and amphibians) may

be indirectly affected by the impact of motorized oversnow recreation on the aquatic

environment. The river otter’s piscivorous diet and high position on the food web may

make it especially vulnerable to water pollution (Melquist and Dronkert 1987). Direct

discharge of snowmachine exhaust into the snowpack may create elevated contamination

by hydrocarbons, carbon monoxide, nitrous oxides, and particulate matter, which may

end up in aquatic ecosystems, including sensitive amphibian habitats (Ruzycki and Lutch

1999). These contaminants can lead to loss of overall health of amphibian populations

and result in direct and indirect mortality of aquatic resources (Adams 1974). See Water

and Aquatic Resources for an assessment of the impacts of exhaust on water quality in

the parks.

Sagebrush lizards hibernate throughout the winter use season but may be impacted by

winter activities that disturb rocky, geothermal areas. Oversnow motorized routes do not

occur in these areas and consequently would not affect sagebrush lizard habitat.

In YNP trumpeter swans that winter along the Lewis, Firehole, Madison, and

Yellowstone Rivers may be affected by motorized oversnow traffic, but disturbance is

considered minor (Wyoming Game and Fish Department, McEneaney, pers. com., 2000).

In GTNP impacts from motorized use are considered negligible because groomed and

ungroomed routes for motorized oversnow use are not immediately adjacent to wintering

areas. Similar to bald eagles, swans demonstrate more tolerance to continually moving

vehicles than they do to stopped ones or people on foot or skis (Shea 1979; Aune 1981).

In the parks, the predictability of vehicles on groomed or otherwise designated routes

allows swans to habituate to traffic thus alleviating impacts related to disturbance.

Effects of plowed roads. Similar to groomed roads, plowed roads also provide an

energy efficient mechanism for wildlife movements. Under alternative A, the effects
IMPACTS OF IMPLEMENTING ALTERNATIVE A — NO ACTION

253

described above are associated with about 76 miles of plowed road in YNP, including US

Highway 191, a commercial 55 mph route linking the communities of West Yellowstone

and Bozeman, Montana. GTNP, including the Parkway, maintains about 100 miles of

plowed road.

Because so few studies of wolverine ecology exist, it is unknown if wolverines would use

plowed routes. Because wolverines are considered especially sensitive to human

disturbance (Copeland 1996) it is unlikely that they would use routes frequently traveled

by humans. Habitat displacement of wolverines has been documented to occur outside

the parks, with wolverines rarely using parts of their home range bisected by roads

(Arthur et al. 1989; Copeland 1996; Gunther et al. 1998 and 1999).

Little information exists that documents the effects of plowed roads on fishers.

Anecdotal information from Alberta documented three individual fishers using snowplow

banks as vantage points to hunt hares browsing on saplings in the rights-of-way (Johnson

and Todd 1985).

The effects of plowed roads on marten movements are unknown.

River otters are closely associated with aquatic and riparian habitats, seldom venturing

far from water. Therefore, otters would not be expected to make use of plowed roads as

travel corridors, but may occasionally cross roads that bisect riparian habitats.

Impacts to trumpeter swans are associated with motorized traffic on plowed roads

(discussed below), and not the roads themselves.

Sagebrush lizards hibernate throughout the winter use season but may be impacted by

winter activities that disturb rocky, geothermal areas. Consequently, plowed roads would

not affect sagebrush lizard habitat.

Impacts to rubber boas, fish, and amphibians are limited to activities that affect the

aquatic environment. In regards to winter use, these impacts are limited to the use of

motorized oversnow vehicles and their effects on water quality. See Water and Aquatic

Resources for an assessment of the impacts of exhaust on water quality in the parks.

Effects of motorized use of plowed roads. The most likely impacts to park species of

special concern are displacement from preferred habitats and mortality caused by

collisions.

As stated previously, habitat displacement of wolverines has been documented to occur

outside the parks, with wolverines rarely using parts of their home range bisected by

roads (Arthur et al. 1989; Copeland 1996; Gunther et al. 1997 and 1999). Therefore, it is

possible that plowed roads and traffic affect wolverines in the parks. Because vast areas

exist in the parks that are not roaded, any effects related to the use of wheeled-vehicles

on plowed roads would be limited.
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Fishers, like wolverines, require contiguous blocks of habitat. Within their home ranges

they reportedly rarely use areas bisected by roads (Arthur et al. 1989; Copeland 1996;

Gunther et al. 1997 and 1999). Because vast areas exist in the parks that are not roaded,

any affects related to the use of wheeled-vehicles on plowed roads would be limited.

The effects of wheeled-vehicle traffic on marten habitat use in the parks are unknown.

Similar to fishers and wolverines, the impact would be negligible because vast areas exist

in the parks that are not roaded. From 1989-98, wheeled-vehicles killed 18 marten in the

winter in YNP (Gunther et al. 1998).

River otters are closely associated with aquatic and riparian habitats, seldom venturing

far from water. Nonetheless, wheeled-vehicles killed a total of seven otters from 1989-

98 in YNP (Gunther et al. 1998). The effects of wheeled-vehicle traffic on otter habitat

use in the parks are unknown.

Under current management, there are no plowed roads immediately adjacent to open

water habitats for trumpeter swans in YNP. In GTNP swans may use open water habitats

of the Snake River near US Highway 287/89/191, but displacement has not been a

significant issue, possibly because swans have habituated to the predictable nature of the

traffic on this highway.

Sagebrush lizards hibernate throughout the winter use season and consequently are not

affected by wheeled-vehicles on plowed roads.

Impacts to rubber boas, fish, and amphibians are limited to activities that affect the

aquatic environment. In regards to winter use, these impacts are limited to the use of

motorized oversnow vehicles and their effects on water quality.

Effects of nonmotorized use on groomed and ungroomed designated routes. The

primary effects of nonmotorized use are displacement from preferred habitats, and

increased energy expenditures, including physiological stress, which may reduce

individuals’ chances of survival. These effects are believed of greater magnitude than

those caused by motorized vehicles using established, predictable routes (Cole 1978;

Schultz and Bailey 1978; Walter 1978; Aune 1981; Cassier 1986). Under alternative A,

YNP maintains 37 miles of groomed nonmotorized trail. GTNP and the Parkway do not

maintain groomed trails for nonmotorized use, but do provide 26 miles of designated

ungroomed routes for nonmotorized use. The area affected by nonmotorized trails in the

parks is very small relative to the total area of the park units. Minor site-specific impacts

are possible where trails occur in or near nesting sites or foraging areas. Nonmotorized

uses of groomed and ungroomed routes occur primarily where vehicular access permits

easy access.

Copeland (1996) reported that human activity near denning wolverines might cause them

to abandon their dens thus potentially affecting reproductive success. Because denning

occurs in late February to early March, it is possible that winter recreation could affect
IMPACTS OF IMPLEMENTING ALTERNATIVE A — NO ACTION

255

denning wolverines. However, wolverines typically den in high-elevation, subalpine

cirque basins (Trochta 1999), therefore any affect associated with winter recreation

would be limited to backcountry travel (discussed below).

Fishers, especially when denning, may be sensitive to human disturbance (Trochta 1999).

Because very little is known about this species and their distribution in the parks, it is

difficult to assess the potential degree of impact from winter recreation, including

nonmotorized use.

Little is known about the sensitivity of martens to human activity. They are described as

inquisitive and may show greater tolerance than wolverines or fishers, having been found

in areas of high human activity (Strickland and Douglas 1987).

Arrhythmic variations in activity patterns have been observed in river otters as a result of

individual differences and human activity (Melquist and Dronkert 1987), with otters

exhibiting more nocturnal or crepuscular activity in disturbed areas. How winter

recreation may affect otters in the parks is unknown.

Swans have shown greater displacement behavior to people on foot or skis than to

motorized traffic (Shea 1979; Aune 1981). They are especially sensitive during the

breeding season, which occurs outside of the period of winter use. Skiing or

snowshoeing near open water habitats may cause swans to flush; however, this is not

considered a major problem for swans in the parks (McEneaney, pers. com., 2000).

Sagebrush lizards hibernate throughout the winter use season but may be impacted by

winter activities that disturb rocky, geothermal areas. Consequently there is a small

potential that visitors to sensitive geothermal areas may disturb lizard habitats.

Impacts to rubber boas, fish, and amphibians are limited to activities that affect the

aquatic environment. In regards to winter use, these impacts are limited to the use of

motorized oversnow vehicles and their effects on water quality.

Unregulated backcountry nonmotorized use. Unregulated backcountry nonmotorized

use is more random and infrequent relative to nonmotorized use on designated routes.

Consequently, although encounters between backcountry users and species of special

concern may only occur sporadically, they can be especially disturbing and lead to

additional energy expenditure and stress that reduces animals’ chances of survival and

reproduction.

Protection of natal denning habitat from human disturbance is critical for wolverine and

fisher persistence (Copeland 1996; Arthur et al. 1989). Backcountry use is largely

unregulated and may displace wolverines from critical denning sites and forage areas.

Wolverine denning habitats are remote, rugged, and difficult to access. Consequently the

odds of backcountry skiers disturbing denning wolverines are low.
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256

Fishers, especially when denning, may be sensitive to human disturbance (Trochta 1999).

Because very little is known about this species and their distribution in the parks, it is

difficult to assess the potential degree of impact from winter recreation, including

nonmotorized use.

Little is known about the sensitivity of martens to human activity. They are described as

inquisitive and may show greater tolerance than wolverines or fishers, having been found

in areas of high human activity (Strickland and Douglas 1987).

Arrhythmic variations in activity patterns have been observed in river otters as a result of

individual differences and human activity (Melquist and Dronkert 1987), with otters

exhibiting more nocturnal or crepuscular activity in disturbed areas. How winter

recreation may affect otters in the parks is unknown.

Swans have shown greater displacement behavior to people on foot or skis than to

motorized traffic (Shea 1979; Aune 1981). They are especially sensitive during the

breeding season, which occurs outside of the period of winter use. Skiing or

snowshoeing near open water habitats may cause swans to flush; however, this is not

considered a major problem for swans in the parks (McEneaney, pers. com., 2000).

Sagebrush lizards hibernate throughout the winter use season but may be impacted by

winter activities that disturb rocky, geothermal areas. Consequently there is a small

potential that visitors to sensitive geothermal areas may disturb lizard habitats.

Impacts to rubber boas, fish, and amphibians are limited to activities that affect the

aquatic environment. In regards to winter use, these impacts are limited to the use of

motorized oversnow vehicles and their effects on water quality.

Presence and use of winter support facilities. The primary effects of warming huts and

campgrounds on park species of special concern are associated with increases in human

activity and the subsequent disturbance and displacement of species or their prey.

Habituation is not a concern for the species discussed below.

Under alternative A, the only new support facility would be the construction of a

warming hut at Norris. This hut would be located in thermally influenced ungulate

winter range. It is possible that increased human presence in the area may displace

ungulates and consequently lower the availability of carcasses for wolverines, fishers,

and martens. The effect would be minor and short term as ungulates habituate to human

activity in the area.

Potential impacts to river otters would be limited to those associated with increased

human activity; specific effects are largely unknown.

The hut site would not be immediately adjacent to swan habitat; therefore, no effects on

swans would occur.
IMPACTS OF IMPLEMENTING ALTERNATIVE A — NO ACTION

257

Sagebrush lizards hibernate throughout the winter use season but may be impacted by

winter activities that disturb rocky, geothermal areas. Consequently there is a small

potential that hikers in sensitive geothermal areas may disturb lizard habitats.

Impacts to rubber boas, fish, and amphibians are limited to activities that affect the

aquatic environment. In regards to winter use, these impacts are limited to the use of

motorized oversnow vehicles and their effects on water quality. See Water and Aquatic

Resources for an assessment of the impacts of exhaust on water quality in the parks.

Conclusion

Most impacts from winter recreation do not result in long-term effects to populations.

The effects of plowed and groomed surfaces on ungulate movements may contribute to

energy savings, but it is uncertain if energy saved is greater than associated effects

incurred from displacement and overall disturbance. The effects of packed surfaces on

carnivores, especially lynx, are unknown and in need of investigation. Mortalities

resulting from collisions with wheeled-vehicles are much higher than with snowmobiles,

and primarily affect ungulates. On a population level, road-kill mortalities are negligible

to minor for all species, but loss of individuals of federally protected species (i.e.,

grizzlies and wolves) is a concern. No documented road-kills of large mammals exist for

snowcoaches (Gunther et al. 1998). Nonmotorized recreation in the front country and

backcountry, with the exception of bighorn sheep, is generally associated with minor to

moderate effects, and has not presented a long-term threat to any park species.

Backcountry skiers may be impacting the imperiled sheep population in GTNP and

effects may be moderate to major without mitigation. The presence and use of winter

support facilities may incur impacts due to habituation to human foods (primarily a

problem for bears) and displacement of species sensitive to human activities.

Displacement effects are considered negligible to minor, and habituation is mitigated by

installation of wildlife-proof winter garbage facilities, a feature of all alternatives.

Although impacts to populations resulting from winter recreation are neither long term

nor very significant, impacts to individual members of the population can be important,

leading to death either directly from collisions or continued harassment, or indirectly

through management actions taken as a response to habituation to human presence and

food. Although concerned about impacts to individuals, for the most part (with the

exception of federally protected species), the NPS bases management actions on the

protection of populations of native animals. For example, see NPS 77, Natural Resources

Management, Chapter II.

Ungulates

• Effects of groomed roads and trails on animal movements — unknown if and to what

extent beneficial effects outweigh negative effects.

• Effects of motorized oversnow use of groomed and ungroomed roads and trails on: (1)

mortality caused by collisions – adverse, negligible, and short term, and (2) displacement

from preferred habitats – adverse, moderate, short term.
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258

• Effects of plowed roads on: (1) habitat fragmentation – adverse, minor, and short term; and

(2) animal movements – unknown if and to what extent beneficial effects outweigh

negative effects.

• Effects of motorized use of plowed roads on: (1) mortality caused by collisions – adverse,

minor, and short term; and (2) displacement from preferred habitats – adverse, moderate,

and long-term.

• Effects of nonmotorized use of groomed and designated ungroomed routes on displacement

from preferred habitats – adverse, minor, and short term.

• Effects of unregulated backcountry nonmotorized use on displacement from preferred

habitats – adverse, moderate, and short term. Impacts to bighorn sheep in GTNP would be

moderate to major and long-term if no mitigation is applied.

• Effects of the presence and use of winter support facilities on displacement – adverse,

minor, and short term.

Federally Protected Species

• Effects of groomed roads and trails on animal movements: (1) bald eagles, grizzly bears,

and wolves — no effect; and (2) lynx – adverse, negligible to major and short term,

depending upon lynx distribution and abundance in the parks.

• Effects of motorized oversnow use of groomed and ungroomed roads and trails on

displacement from preferred habitats – adverse, negligible, and short term for all species

excluding the grizzly bear, which, for the most part, will not be active during the winter use

season.

• Effects of plowed roads on: (1) habitat fragmentation – no effect on any of the listed

species; and (2) animal movements – no known effect on any of the listed species.

• Effects of motorized use of plowed roads on: (1) mortality caused by collisions – adverse,

negligible, and short term (bald eagles and grizzly bears); adverse, minor, and short term

(wolves); no known effect to date on lynx; and (2) displacement from preferred habitats –

adverse, negligible, and short term (bald eagles), no effect (grizzly bears); no known effect

to date on wolves and lynx.

• Effects of nonmotorized use of groomed and designated ungroomed routes on displacement

from preferred habitats – adverse, negligible, and short term (bald eagles); no effect

(grizzly bears); no known effect to date on wolves and lynx.

• Effects of unregulated backcountry nonmotorized use on displacement from preferred

habitats – adverse, minor, and short term (bald eagles); adverse, negligible, short term

(grizzly bears); no known effect to date on lynx and wolves.

• Effects of the presence and use of winter support facilities on displacement – no affect

(bald eagles); adverse, negligible, and short term (grizzly bears, with mitigation); adverse,

minor, and short term (wolves); no effect on lynx because the Norris Warming Hut will not

be in lynx habitat.

Species of Special Concern

• Effects of groomed roads and trails on (1) animal movements – no known effect

(wolverines); adverse, negligible, and short term (fishers, martens); no effect (otters, swans,

reptiles, amphibians, and fish); (2) foraging activities – adverse, negligible, and short term

(marten); no effect on the other species; and (3) subnivian prey availability — adverse,

negligible, and short term (marten); no effect on the other species.

• Effects of motorized oversnow use of groomed and ungroomed roads and trails on

displacement – no known effect (wolverine); adverse, negligible, and short term (fishers

and marten); no effect (otters, reptiles, amphibians, and fish); adverse, minor, and short

term (swans).

• Effects of plowed roads on animal movements – no known effect (wolverines, fishers, and

martens); no effect (otters, swans, reptiles, amphibians, and fish).
IMPACTS OF IMPLEMENTING ALTERNATIVE A — NO ACTION

259

• Effects of motorized use of plowed roads on (1) displacement from preferred habitats –

adverse, negligible, and short term (wolverines, fishers, martens); no effect (otters, swans,

reptiles, amphibians, and fish) and (2) mortality from collisions — adverse, negligible, and

short term (otters and martens); no effect to date on other species.

• Effects of nonmotorized use of groomed and designated ungroomed routes on displacement

from preferred habitats – no effect (wolverines); no known effect (fishers, martens, and

otters); adverse, minor, and short term (swans); adverse, negligible, and short term

(sagebrush lizard) no effect (rubber boa, amphibians, and fish).

• Effects of unregulated backcountry nonmotorized use on displacement from preferred

habitats – adverse, negligible, and short term (wolverines and sagebrush lizard); no known

effect (fishers, martens, and otters); adverse, minor, short term (swans); no effect (rubber

boa, amphibians, and fish).

• Effects of the presence and use of winter support facilities on displacement of potential

prey (carcass) availability – adverse, minor, and short term (wolverines, fishers, and

martens); no effect (swans, rubber boa, amphibians, and fish); no known effect (otters);

adverse, minor, and short term (sagebrush lizard).

Mitigation

• Closures around wolf dens and swan and eagle nests would continue to be implemented.

Closures would be posted and enforced for the duration of time during which the species is

most sensitive to human disturbance.

• The monitoring and evaluation of backcountry nonmotorized use in GTNP should be

enhanced and closures to use should be implemented as warranted.

• Ramps or pullouts where moose could exit plowed roads to reduce collisions between

snowmobiles and moose along the CDST would be provided.

• Use of groomed and plowed surfaces by bison and other ungulates would continue to be

monitored.

• Snow track surveys for carnivores (including lynx) on both groomed and ungroomed routes

would be conducted.

Effects on Natural Soundscape

Audibility analysis — combined effects of all wheeled and oversnow vehicles.

Table 72 presents the acres of park land by road segment where any wheeled or

oversnow vehicle noise would be audible under the two background conditions,

“average” and “quiet”, as defined in the Assumptions and Methodologies section of this

chapter. For each background condition, acreage is presented for three categories of

audibility: (1) audible for any amount of time (labeled “audible at all”); (2) audible for

10% of the time or more; and (3) audible for 50% of the time or more. Appendix M

contains tables with distances to audibility for each segment for each alternative.

The results show that for the no action alternative, under average background sound level

conditions during the time during the day, oversnow and/or wheeled-vehicles would be

audible to some degree for over 181,000 acres in the three park units. For over 94,000 of

those acres, oversnow or wheeled-vehicles would be audible for at least 10% of the time

during the day. For 23,000 of those acres, they would be audible for at least half of the

time during the day. These acreage totals increase by 11% to 4% for the “quiet”

background conditions.

The segment from Moran Junction to the South Entrance of GTNP, which carries a great

deal of wheeled-vehicle traffic unrelated to the alternatives, contributes the greatest to the
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ENVIRONMENTAL CONSEQUENCES

260

total acreage values for all three audibility categories. Since the traffic and its high level

of audibility remain almost constant for all the alternatives, the magnitude of audibility

effects is somewhat masked.

The second largest contributor to the “audible at all” and “audible 10% or more”

categories is Jackson Lake, with its snowplanes and snowmobiles. The 50-foot noise

emission level used for snowplanes was 90 dBA, higher than the regulated 86 dBA,

based on data collected in 1995 and 1996. (Bowlby & Associates 1995, 1996) The

effect is even more evident when noting that Jackson Lake is the fourth shortest of the

twenty analyzed “road” segments; the reason is the very high noise emission level of the

snowplanes. However, Jackson Lake is not a contributor to the “audible 50% or more”

categories because of the relatively low number of snowplanes and snowmobiles in use.

The plowed road from Mammoth to the YNP Northeast Entrance is a major contributor

to the “audible at all” acreage (and, to a lesser extent, “audible 10% or more”), which

remains virtually unchanged across all of the alternatives.

Other major contributors to the “audible at all” and “audible 10% or more” acreage are

the Fishing Bridge-West Thumb and West Thumb-Flagg Ranch segments.

The other key segments for the “audible 50% or more” categories are from the YNP

West Entrance to Madison and from Madison to Old Faithful.

Average sound level analysis

To give a sense of the effect of the number of oversnow or wheeled-vehicles on a road

segment, and their speed and sound level, Table 73 shows the computed hourly

equivalent or “average” sound level (Leq) over the daytime period. Levels are shown for

each road segment at two distances, 100 feet and 4,000 feet, and for both open and

forested terrain. These hourly Leq values do not have the background sound level added

in to them. Also, they cannot be compared against the background levels to assess

audibility, since Leq values represent a long-term average of both quiet and loud

moments.

These hourly Leq values show that the segment representing Jackson Lake (snowplanes

and snowmobiles), plus the segments from the YNP West Entrance to Madison and

Madison to Old Faithful (snowmobiles and snowcoaches) have the highest average sound

levels at any given point along them.

Conclusion

The no action alternative impacts the soundscape of very large areas of the three park

units. The sources are the snowmobiles and snowcoaches in YNP and a combination of

snowplanes, snowmobiles, and wheeled-vehicles in GTNP and along the Parkway. A

major portion of the impacted acreage is due to through traffic on US 26 for the road

segment from Moran Junction to the sound environment of GTNP. Snowplanes and

snowmobiles on Jackson Lake are also major contributors to audibility for at least 10% of
IMPACTS OF IMPLEMENTING ALTERNATIVE A — NO ACTION

261

the time. Except for US 26, the only other areas with significant audibility 50% of the

time or more are the segments in YNP from the West Entrance to Madison and from

Madison to Old Faithful.

Table 72. Acres of park land affected by vehicle audibility.

With Average Background

Conditions

With Quiet Background

Conditions

Road Segment Miles

Audible

at All

Audible 10%

of the Time

or More

Audible 50%

of the Time

or More

Audible

at All

Audible 10%

of the Time

or More

Audible

50% of

the Time

or More

1. Mammoth to Northeast Entrance 47 16,126 5,445 0 16,822 6,342 0

2. Mammoth to Norris 21 11,400 761 0 12,372 1,043 0

3. West Entrance to Madison 14 8,032 6,482 5,282 10,090 7,060 6,032

4. Madison to Norris 14 6,853 5,505 347 7,249 6,029 419

5. Norris to Canyon Village 12 5,443 3,955 0 5,683 4,420 0

6. Canyon Village to Fishing Bridge 16 9,999 6,559 0 11,173 7,426 166

7. Fishing Bridge to East Entrance 27 10,760 1,381 0 11,762 1,582 0

8. Fishing Bridge to West Thumb 21 15,645 9,490 0 17,785 10,884 0

9. Madison to Old Faithful 16 8,781 7,583 5,546 11,064 8,324 6,604

10. Old Faithful to West Thumb 17 7,713 6,057 0 8,053 6,643 0

11. West Thumb to Flagg Ranch 24 12,716 8,781 671 13,577 9,884 944

12. Grassy Lake Road 7.6 3,033 0 0 3,303 0 0

13. Flagg Ranch to Colter Bay 15.6 7,706 3,225 0 8,344 3,574 0

14. Colter Bay to Moran Junction 10.2 4,631 2,434 0 5,019 2,669 0

15. Moran Junction to East Entrance 2 1,225 755 489 1,319 866 534

16. Moran Junction to South Entrance 26 21,714 14,536 11,123 23,842 16,922 11,825

17. Teton Park Road 15 7,805 0 0 8,512 0 0

18. Moose-Wilson Road 2.5 1,007 0 0 1,053 0 0

19. Antelope Flats Snowmobile Route -- No Veh.† No Veh. No Veh. No Veh. No Veh. No Veh.

20. Jackson Lake 9.7 20,540 11,649 0 23,655 13,706 0

TOTAL 181,127 94,599 23,459 200,676 107,373 26,525

†No Veh. = No Vehicles
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ENVIRONMENTAL CONSEQUENCES

262

Table 73. Average hourly Leq from wheeled and oversnow vehicle noise at two

distances to each road segment for alternative A.

Leq at Distance (dBA)

Open Terrain Forested Terrain

Road Segment 100 feet 4,000 feet 100 feet 4,000 feet

1. Mammoth to Northeast Entrance 35 2 33 0

2. Mammoth to Norris 44 4 42 0

3. West Entrance to Madison 56 16 54 8

4. Madison to Norris 53 13 51 5

5. Norris to Canyon Village 51 12 50 4

6. Canyon Village to Fishing Bridge 50 10 49 2

7. Fishing Bridge to East Entrance 44 4 43 0

8. Fishing Bridge to West Thumb 50 10 48 2

9. Madison to Old Faithful 56 16 54 8

10. Old Faithful to West Thumb 52 12 50 4

11. West Thumb to Flagg Ranch 51 11 50 3

12. Grassy Lake Road 42 2 41 0

13. Flagg Ranch to Colter Bay 44 7 42 0

14. Colter Bay to Moran Junction 44 9 43 1

15. Moran Junction to East Entrance 47 13 45 5

16. Moran Junction to South Entrance 46 14 44 6

17. Teton Park Road 39 0 37 0

18. Moose-Wilson Road 34 0 32 0

19. Antelope Flats Snowmobile Route No Veh. No Veh. No Veh. No Veh.

20. Jackson Lake 58 12 56 4

Effects on Cultural Resources

Because this alternative reflects current use and management practices in the three parks,

there would be no new direct or indirect impacts to cultural resources. Ongoing cultural

resource management activities would continue to be directed toward the long-term

preservation of cultural resources.

Conclusion

The protection, preservation, and interpretation of cultural resources would follow

existing trends and, with appropriate mitigation, there would be no adverse impacts to

such resources.

Effects on Visitor Access and Circulation

Access

How visitors currently arrive at the park, the activities they participate in, and the

facilities available to accommodate varying modes of transportation are described in
IMPACTS OF IMPLEMENTING ALTERNATIVE A — NO ACTION

263

Chapter III. All facilities, activity use levels, modes of transportation, and circulation

patterns would remain the same. No changes are assumed in alternative A. The

following table provides baseline winter-use levels by activity at multiple facilities and

destination areas within the park units.

Table 74. Existing winter use visitation by facility or destination area.

Park / Facility Snowmobile

CrossCountry

Skiing /

Snowshoe

Snowcoach

Tours Snowplanes

WheeledVehicles

Yellowstone National Park

North Entrance None None None N/A Moderate

Northeast Entrance None Light None N/A Moderate

East Entrance Light Light None N/A None

South Entrance Moderate None Moderate N/A None

West Entrance High Light High N/A None

Mammoth Light High Moderate N/A Moderate

Tower-Roosevelt None High None N/A Moderate

Canyon Village Moderate Moderate Moderate N/A None

Fishing Bridge Moderate Light Light N/A None

Lake Village Moderate Light Light N/A None

Bridge Bay Moderate Light Light N/A None

West Thumb Moderate Light Moderate N/A None

Grant Village Moderate Light Moderate N/A None

Old Faithful High High High N/A None

Madison High Light High N/A None

Norris Moderate Light Moderate N/A None

Grand Teton National Park / JDR Memorial Parkway

Moran Entrance Moderate None None N/A High

South Entrance None None None N/A High

Moose-Wilson Road Light Moderate None N/A Light

Flagg Ranch High Moderate Moderate N/A Moderate

Colter Bay Moderate Moderate None High High

Signal Mountain Moderate Moderate N/A Light Moderate

Jenny Lake Light High N/A N/A N/A

Moose Visitor Center None Light N/A N/A Moderate

Triangle Ranch Light None N/A N/A None

The following table shows current use on all road segments of the three park units in

terms of average daily use based on the peak use months of January and February. See

Appendix J and the Methods and Assumptions section earlier in Chapter IV for more

information on how this usage was determined. Appendix J also contains similar tables
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

264

that show the number of vehicle-miles that would be traveled on an average daily basis,

for each alternative scenario.

Table 75. Alternative A current motorized use.

Average Daily Use January-February

Road Segment Autos Buses/Vans Snowcoaches Snowmobiles

Mammoth to Northeast Entrance 61 4.2 0 0

Mammoth to Norris 0 0 3.3 30.5

West Entrance to Madison 0 0 9.1 554.2

Madison to Norris 0 0 5.2 247.0

Norris to Canyon Village 0 0 3.9 184.5

Canyon Village to Fishing Bridge 0 0 3.1 148.1

Fishing Bridge to East Entrance 0 0 0 36.4

Fishing Bridge to West Thumb 0 0 2.6 125.1

Madison to Old Faithful 0 0 10.3 488.6

Old Faithful to West Thumb 0 0 4.3 209.4

West Thumb to Flagg Ranch 0 0 4.3 175.8

Grassy Lake Road 0 0 0 24.2

Flagg Ranch to Colter Bay 86 9.5 0 24.3

Colter Bay to Moran Junction 192 10 0 24.3

Moran Junction to East Entrance 562 29 0 24.3

Moran Junction to South Entrance 773 39 0 0

Teton Park Road 0 0 0 10.4

Moose-Wilson Road 5 0 0 3

Antelope Flats Snowmobile Route 0 0 0 0

Concession Services

In the Affected Environment section under the main heading of Visitor Access and

Circulation there is a discussion relevant to concessions offered in the parks, titled “Park

Facilities and Winter Destination Areas.” Within this discussion are the subtopics of

“lodging,” “parking,” and “other winter services and facilities.” In alternative A, under

current management, the concession related facilities and services noted in the Affected

Environment would remain the same. It should be noted that concession plans and

contracts provide for some management flexibility over time to deal with changing

circumstances, needs and markets. Even under current management direction, changes

would be expected to occur in concessions operations.

Conclusion

All facilities, modes of transportation, and circulation patterns and use trends would

remain the same as described in Chapter III, in the Affected Environment section relating

to access.
IMPACTS OF IMPLEMENTING ALTERNATIVE A — NO ACTION

265

Effects on Visitor Experience

The amount and type of winter visitor opportunities offered in the parks under the no

action alternative are provided in Table 76 and Table 77.

Table 76. YNP visitor opportunities.

Opportunity Miles or Areas Length of Season

Oversnow motorized route 184 Mid-December to Mid-March

Oversnow motorized route —

snowcoach 158.6. Mid-December to Mid-March

Oversnow motorized trail 0 Mid-December to Mid-March

Plowed route 76 Mid-December to Mid-March

Groomed nonmotorized 37 Mid-December to Mid-March

Warming huts 6 Mid-December to Mid-March

Backcountry 2.2 million acresContingent on snowfall in northern

portion of park

Table 77. GTNP and the Parkway visitor opportunities.

Opportunity Miles or Areas Length of Season

Oversnow groomed motorized route 2.1 December to April†

Oversnow groomed motorized route

–snowcoach 0

December to April†

Oversnow groomed motorized trail 33.9 December to April†

Plowed road 100.1 December to April†

Ungroomed motorized trail or area 35.6

and Jackson Lake

Groomed nonmotorized 0. December to April†

Ungroomed nonmotorized trail or area 26.4

Warming huts/Interpretive centers 2 December to April†

†Variable, dependent on snow conditions

Visitor Experience and Satisfaction

In alternative A, the various types of visitor experience and levels of satisfaction would

remain as introduced in the Affected Environment section. The criteria listed below were

defined by visitor responses to various surveys of winter visitors in the three park units.
CHAPTER IV

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266

Opportunities to View Wildlife. Most winter visitors rate wildlife viewing as a primary

or important reason for visiting the parks. Most visitors are generally satisfied with the

amount of wildlife viewing opportunities currently available. One of the top three

reasons for visiting YNP cited by Borrie et al. (1999) was to view bison.

Opportunities to View Scenery. Most winter visitors to YNP and GTNP (Littlejohn

1996; Borrie et al. 1999) rate viewing scenery as a primary reason for their visit. Visitors

indicated that they were for the most part “totally” satisfied with the quality of scenery in

the parks.

The Safe Behavior of Others. Snowmobile and skiers rate this factor as important and

indicate that it has an influence on the enjoyment of their visit. Many visitors indicate

that the dual use of trails and areas for both snowmobiling and skiing contributes to the

perception of an unsafe environment. Under the no action alternative, the experience of

visitors would continue to be impacted.

Quality of the Groomed Surface. More than 80% of winter visitors rate the quality of

the road surface as very important. The groomed surface from West Entrance to Old

Faithful is frequently very rough and the quality of snow cover is poor. The CDST

oversnow surface is frequently in poor condition, as is the Grassy Lake Road. Under the

no action alternative these conditions would continue.

The Availability of Access to Winter Activities or Experiences. Nearly all

respondents to a recent survey (Borrie et al. 1999) supported oversnow mechanized

access. More than 90% of winter visitors surveyed did not support plowed roads and

snowcoach-only travel. Most winter visitors valued highly the winter experience in the

parks and felt it was a special and unique experience. Winter respondents to the 1998-99

winter visitor survey (Duffield et al. 2000a) also favored access to the parks by

snowmobile. Respondents to the summer (Duffield et al. 2000b) and telephone surveys

(Duffield et al. 2000c) were more evenly divided between support for groomed roads for

snowmobiles and support for groomed access for snowcoaches. Plowed access also

received very low support from the summer and telephone survey respondents.

Similarly, in a count of public comments supporting various alternatives in the DEIS,

there was an even split between numbers of letters supporting groomed access for

snowmobiles (44%) and those supporting groomed access for snowcoaches only (45%).

Very little support was indicated for the proposal to plow the West Yellowstone to Old

Faithful road.

Availability of Information. Surveyed winter visitors indicate that the availability of

safety information is very important. Accurate and readily available information about

safe travel practices and winter conditions is one of the suggested management actions

that received a high level of support from most respondents.

Quiet and Solitude. Most survey respondents felt that natural quiet and solitude was

important to the quality of their park visit. A recent study indicates that respondents
IMPACTS OF IMPLEMENTING ALTERNATIVE B

267

ranked experiencing tranquility and peace and quiet and getting away from crowds as

highly important (Borrie et al. 1999). Although an important value, many visitors

responded that they were somewhat dissatisfied with their ability to experience quiet and

solitude. Opportunities for quiet would continue to be minimal over 50% of the time

along the road from West Yellowstone to Old Faithful and 10% of the time near Jackson

Lake and along US 26 from Moran Junction to the South Entrance to Yellowstone.

Clean Air. Clean air was important to most visitors (Littlejohn 1996). Surveyed visitors

indicated a high level of support for management actions requiring clean and quiet

snowmobiles (Duffield et al. 2000c; Borrie et al. 1999). Snowmachine emissions on high

use days are often visible along the road corridors and at staging areas, particularly at Old

Faithful, near the West Entrance, and at Flagg Ranch near the South Entrance of YNP.

Conclusion

Visitor experience trends in YNP, GTNP, and the Parkway under the no action

alternative would continue. Little or no operational change would occur under this

alternative resulting in a negligible short-term effect in the range of experiences offered.

Visitation would be influenced by the method of transportation available to visitors.

Incremental increases in visitation would have a short-term negligible effect on the

satisfaction of the current winter visitor.

Encounters with park wildlife and scenery would continue to be primary attractions. The

overall satisfaction of winter visitors would remain high. Current levels of snowmobile

emissions and sound levels would continue to detract from the winter experience for

many visitors resulting in direct short-term major impacts on visitor experience. The

perceived unsafe behavior of others and the occurrence of visitor conflicts would

continue to have a direct short-term moderate adverse effect on the experience of some

users.

IMPACTS OF IMPLEMENTING ALTERNATIVE B

Effects on the Socioeconomic Environment

GYA Regional Economy. Alternative B includes a number of provisions for relatively

minor changes in management and grooming of trails within YNP and GTNP. Most of

these changes are unlikely to impact visitor decisions on whether or not to visit the parks

for recreation. One proposed management change, however, has the potential to

substantially impact visitation levels to the GYA and, therefore, visitor expenditures and

the overall level of economic activity within the GYA.

Alternative B contains a proposal to plow the road from West Yellowstone to Madison

Junction to Old Faithful. The 1999 GYA winter visitor survey asked respondents how

their visitation would be affected if this road segment were plowed and open for car and

bus travel only. Based on the responses to this survey question, visitation to the GYA by

winter visitors who live outside of the five-counties would be reduced by 18.4% if the

road from West Yellowstone to Old Faithful were plowed and open only for car and bus
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268

travel. Park visitors who reside outside of the five-county GYA made up 85.9% of total

sampled visitors. This estimated reduction in visitation is a net change, which takes into

consideration the responses of those current winter visitors who said they would visit

more often if the change occurred. Also considered in the calculation were those

respondents who said they would visit the same, but would shift their use to other areas

of the GYA (for example, from park lands to national forest lands).

If 18.4% of the non-GYA resident visitors decided not to recreate within the five counties

because of the plowing of the West Yellowstone to Old Faithful road, the local economy

would lose the local-area expenditures these potential visitors would have made.

Using the winter survey responses and an IMPLAN input/output model, it is estimated

that total economic output in the five-county GYA area would be reduced by $13.2

million under alternative B. In addition it is estimated that 312 jobs within the five

counties would be lost due to reduced nonresident expenditures in the area.

While $13.2 million is a negligible to minor impact on the overall $5.7 billion economic

output of the five-county area, this impact likely would be concentrated in small

communities such as West Yellowstone. Currently about 50% of winter visitors to the

parks enter through the West Entrance. The winter economy of West Yellowstone,

Montana is centered around tourists who have come to the area to recreate in the park as

well as on surrounding national forest lands. Because of the small size of the West

Yellowstone economy, its relatively large share of the park’s snowmobile visitors, and its

proximity to the affected road segment, it can be assumed that the town will bear a

disproportionately large share of the nonresident expenditure reductions.

The town of West Yellowstone levies a local option tax targeted at tourist spending. Tax

records show that for the period 1989-1999, tourist expenditures have been growing at a

10% annual rate. In addition tourist spending in the winter months accounts for about

25% of year-round tourist spending in the town. Given the relative size of the West

Yellowstone winter economy (relative to year-round totals) and the recent growth trends

for tourist spending, the estimated visitation reductions associated with alternative B

would likely have a moderate to major short-term negative impact on the town’s winter

economy, but a minor impact on the year-round economy of the town.

The estimates of reductions in GYA visitation and nonresident expenditures are based on

responses to a survey of current winter visitors. The estimated reductions in local-area

spending could be lessened if users chose to utilize the new opportunity to access Old

Faithful via a shuttle bus. Some shift in use patterns would be expected as visitors

become aware of the wheeled-vehicle access opportunities. The shift in visitation should

be accompanied by a shift in businesses to support these users. The extent that new users

from outside the GYA would be attracted to the area because of the alternative B plowing

action is not known at this time.
IMPACTS OF IMPLEMENTING ALTERNATIVE B

269

The possible effects of alternative B on visitors entering the parks from the south are not

quantifiable since no specific data exists. Recent visitor surveys have focused on

understanding visitor reactions to the management actions that have the likelihood to

affect large numbers of visitors. For the balance of the management actions that may

affect smaller numbers of visitors, qualitative statements are possible. Providing the

CDST on a separate route may attract more snowmobile users to GTNP and the Parkway

because the CDST may become an attraction in its own right and may provide a better

experience for visitors traveling from Moran to Flagg Ranch. In addition some

snowmobile users that might have traveled into YNP via the West Entrance may choose

to enter the parks via Jackson. These potential increases may be offset by the closure of

the Teton Park Road, which is used by about 1,100 snowmobiles per winter, to motorized

use. The increases also will be tempered by the limit on parking capacity at Flagg Ranch

and the relatively long travel distance from Jackson to Flagg Ranch and from Flagg

Ranch to destinations in YNP. These changes in use patterns may result in a minor

increase in use in GTNP and the Parkway and, therefore, a minor increase in visitor

expenditures.

Three-State Regional Economy. Overall, 65.5% of winter visitors in the GYA winter

visitor survey came from outside the three-state area of Montana, Idaho, and Wyoming.

Responses from these nonresident winter visitors indicate that there would be a reduction

of 18.6% of winter trips to the three-state area under the alternative B plowing proposal.

A loss of the regional expenditures by these nonresidents would lead to an overall

reduction of $14.4 million in total economic output and 351 jobs in the three-state area.

This is a negligible negative impact in the context of the regional three-state economy.

This estimated reduction would be reduced to the extent that nonresidents would choose

to recreate at other locations within the three-state region instead of in the GYA. The

extent of any such substitution behavior is unknown.

Minority and Low-Income Populations. One of the stated actions under alternative B

is to “provide affordable access through the addition of wheeled-vehicle access to the

park’s interior.” Currently, mechanized access to Old Faithful from West Yellowstone

can be accomplished using only snowmobile or snowcoach. For visitors without

personal snowmobiles, the cost of renting a snowmobile to access Old Faithful and the

remaining park trails is about $100 per day. The current cost of riding a snowcoach into

Old Faithful from West Yellowstone is about $85. Alternative B proposes an alternative

mode of mechanized access: buses and private automobiles. It is anticipated that the

shuttle bus would be offered at a relatively low cost of $30 to $40. The estimated

reduced cost of accessing Old Faithful using a shuttle bus compared to renting a

snowmobile or using a snowcoach is about $70 per person.

Trip expenditures per person to the parks in the GYA vary significantly between those

visitors who report having the lowest household income and those who report having the

highest. Winter survey respondents who reported incomes below $15,000 per year spent
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

270

an average of $329 per person on their 1999 winter trip. Those respondents reporting

incomes of $150,000 and above reported spending $1,150 per person on their trips.

This is a minor to moderate beneficial impact. However, it is not clear that plowing the

road would actually change the mix of lower, middle, and higher income visitors to the

parks. Summer visitors do not face the high costs of snowmobile rental or snowcoach

use, yet the income distribution of summer and winter visitors to YNP is quite similar.

The share of the total visitor costs that can be affected by park policy is relatively low.

If the cost of accessing Old Faithful from West Yellowstone was reduced by $70 per

person, winter visitors with household incomes under $15,000 per year would save about

21% in trip costs, as opposed to a 6% decrease in trip costs for visitors with incomes over

$150,000.

Social Values. In anticipation of the inclusion of a number of road management options

in the EIS alternatives, the winter visitor survey asked respondents what was their

preferred means of access from West Yellowstone to Old Faithful in the winter months.

For the entire sample of park visitors, 56.6% preferred the existing policy of grooming

for snowmobile use. A total of 13.1% preferred plowing the road and grooming a

parallel route for snowmobile use. A total of 6.5% chose closing the route to

snowmobiles and allowing ski or snowshoe use only. Another, 19.7% chose to allow

snowcoach, ski, and snowshoe travel only on this route. The least preferred option was

the alternative B proposed action of plowing the road without any parallel trail for

snowmobile use, which was supported by 4.2% of respondents.

Two additional questions on winter travel route management within the park were asked

on the winter visitor survey. These questions were asked in the context of the impact

winter travel within the park has on bison management. Among park visitors, 52.1%

favored the current bison and road management policies that allow winter access for

oversnow vehicles and largely regulate bison populations and movements at park

boundaries. Another 23.6% favored closing motorized winter access to the park by

ceasing to groom park roads from West Yellowstone to Mammoth to better allow natural

forces such as weather, nutrition, and winterkill to regulate bison populations. The

remaining 24.2% of respondents said they were not sure which policy they preferred.

When the winter respondents were asked the same question again with the addition of a

choice for plowing the road from West Yellowstone to Old Faithful, responses were

distributed in the following way: 55.3% favored the existing policy; 23% favored closing

motorized winter access, 4.7% favored plowing the road from West Yellowstone to Old

Faithful, and 17.1% were not sure which policy they preferred.

Responses to these three questions show a consistent picture of very low support among

current winter visitors to the GYA for the major management change contained in

alternative B — plowing the road from West Yellowstone to Old Faithful.
IMPACTS OF IMPLEMENTING ALTERNATIVE B

271

Responses to the YNP summer visitor survey and the national telephone survey were also

consistent in showing very low support for the alternative B road plowing option (see

Chapter III).

Nonmarket Values. The proposed alternative B actions would potentially impact

nonmarket values of winter visitors in several ways. The estimated reduction in current

winter user visitation resulting from the plowing of the West Yellowstone to Old Faithful

road would impact total nonmarket trip values. The proposed clean and quiet

snowmobile regulations for winter 2008-2009 would impact the nonmarket values that

current snowmobile users place on a cleaner, quieter means of snowmobiling in the park.

Finally, the plowing of the West Yellowstone to Old Faithful road segment would impact

the nonmarket value associated with having this type of auto and bus access to the park.

The nonmarket value of a trip to the parks of the GYA, based on the winter visitor

survey, is $91. It is estimated that park visitation would be reduced by 18.4% resulting

from the plowing of the road. Based on current winter visitation levels, a 18.4%

reduction in visitation would translate into a $1.5 million reduction in the aggregate

nonmarket value of winter trips to the parks. This is a moderate negative impact.

Respondents to the winter survey who rented a snowmobile on their trip were asked if

they would be willing to pay a higher rental fee to rent a snowmobile that was as clean

and quiet running as a typical new car. The median willingness to pay to rent a clean,

quiet machine was an additional $46 per day above the current cost of renting the

machine. To the extent that clean and quiet snowmobiles would be more expensive to

rent, this $46 net economic value would be reduced.

In the 1999 winter user survey, 41.8% of respondents (including non-snowmobiling

visitors) reported renting a snowmobile on their park trip. Based on this percentage of

rentals, if only clean, quiet snowmobiles were available and exclusively rented within the

park today, visitors who rent snowmobiles within the park would realize an increase in

aggregate net economic value of $1.7 million. To the extent that the rental price of a

clean, quiet machine is more than current rental rates, this aggregate value will be

reduced. If the rental cost of a clean and quiet machine is $46 more per day than current

rental rates, the estimated net economic value to renters will be reduced to near zero.

This is a moderate beneficial impact relative to the total value of a current trip.

A final source of changes in net economic value of a trip to the parks of the GYA is

associated with the proposed plowing of the West Yellowstone to Old Faithful road.

Winter visitors for whom YNP was a destination on their trip were asked if they would

pay an additional fee to cover the cost of plowing the road from West Yellowstone to Old

Faithful. The median willingness to pay for winter car and bus access to Old Faithful

was estimated to be $6 per person. Based on this estimate, the estimated net economic

value of the road access to the park would be $440,000. This is a minor positive impact

for those who would continue to visit this park.
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ENVIRONMENTAL CONSEQUENCES

272

Both the estimates for net economic value of clean quiet snowmobiles and for road

access to the park take into consideration the estimated reduction in visitation to the park

that would occur under this alternative due to the plowing activities. These estimates are

based on reduced use by current visitors.

Conclusion

The alternative B road plowing actions would have a negligible to minor impact on the

five-county and three-state economies through reduced visitation and nonresident visitor

expenditures. These expenditure reductions may be a moderate negative impact on small

communities adjacent to the park. The alternative B road plowing actions also would

have a moderate negative impact on total current trip nonmarket visitor benefits (through

reduced visitation), and a minor positive impact on nonmarket benefits through improved

winter access to Old Faithful. Snowmobile renters in the parks would see a moderate

benefit from requirements for clean and quiet machines within the park in future years.

Low-income visitors could realize a minor to moderate benefit from the alternative B

actions, which would make access to the park more affordable.

Air Quality and Public Health

In this alternative, snowmobiles would no longer enter YNP at the West Entrance and

travel to Old Faithful. These snowmobiles and snowcoaches would be displaced by

wheeled-vehicles, including mass transit vans that would operate on a plowed road from

the West Entrance to Old Faithful. In addition by winter 2008-2009, oversnow vehicle

emission rates would be 40% of the baseline CO emission rate, 75% of the baseline PM10

rate, and 70% of the baseline hydrocarbon emission rate. Table 78, Table 79, and Table

80 summarize the results of CO modeling for six locations in the three parks for

alternative B. Table 78 and Table 79 show the predicted maximum 1-hour average CO

concentrations and the calculated maximum 8-hour average CO concentrations,

respectively. The percent contribution of each vehicle type, including snow plows, to the

maximum CO concentrations also is provided in Table 80 for the six locations. Table 81

and Table 82 provide corresponding model results for PM10 for the same locations and

conditions as those for CO.

Visibility

The visibility assessment indicates that under this alternative, vehicular emissions would

not cause any perceptible visibility impairment in the vicinity of the West Entrance or

along the roadways. Perceptible visibility degradation could occur in the vicinity of Old

Faithful and Flagg Ranch when vehicles idle for extended periods.

Conclusion

As noted in Table 78, Table 79, and Table 81, the model predicts major beneficial

impacts relative to alternative A at the West Entrance and along the West Entrance to

Madison roadway, for the peak traffic hour on high winter use days. Both CO and PM10

concentrations would be reduced by more than 85%. Negligible CO reductions are
IMPACTS OF IMPLEMENTING ALTERNATIVE B

273

predicted for alternative B at the staging areas, and a minor adverse impact on CO

concentration is predicted along the Flagg Ranch to Colter Bay roadway due to minor

estimated increases in wheeled-vehicles using this roadway. For PM10, a moderate

beneficial impact would be realized at the Old Faithful staging area, but a minor adverse

impact is predicted for the Flagg Ranch staging area.

Table 78. Maximum 1-hour average CO concentrations for alternative B.

Location

1-hr Maximum

Concentration

(w/o Background)

(ppm)

1-hr Maximum

Concentration

(w/Background)

(ppm)

Change

Relative to

Alternative A

(w/o Background)

(%)

West Yellowstone Entrance 3.30 6.30 88.7

West Entrance to Madison Roadway 0.70 3.70 94.1

Old Faithful Staging Area .88 3.88 31.3

Flagg Ranch Staging Area 1.19 4.19 30.8

Flagg Ranch to Colter Bay Roadway 1.00 4.00 9.1

Mammoth to NE Entrance Roadway 0.30 3.30 0.0

Table 79. Maximum 8-hour average CO concentrations for alternative B.

Location

8-hr Maximum

Concentration

(w/o Background)

(ppm)

8-hr Maximum

Concentration

(w/Background)

(ppm)

Change

Relative to

Alternative A

(w/o Background)

(%)

West Yellowstone Entrance 1.55** 2.96** 88.7

West Entrance to Madison Roadway 0.33** 1.74** 94.1

Old Faithful Staging Area 0.15 1.55 31.3

Flagg Ranch Staging Area 0.20 1.60 30.8

Flagg Ranch to Colter Bay Roadway 0.47** 1.88** 9.1

Mammoth to NE Entrance Roadway 0.14** 1.55** 0

** Estimated from the modeled maximum 1-hour average concentration based on the persistence formula

 Ct2 = Ct1*(t1/t2)^0.365 (Cooper and Alley 1990).

Table 80. Vehicle contribution to CO concentrations for alternative B.

Contribution (%)

Location SM SC AM LT HT TB SV

West Yellowstone Entrance 0 0 12.5 23.4 1.0 0.6 62.5

West Entrance to Madison Roadway 0 0 10.1 24.2 0.6 0.4 64.6

Old Faithful Staging Area 62.1 1.2 4.4 8.7 0.1 0.1 23.4

Flagg Ranch Staging Area 69.3 1.2 8.9 17.6 0.1 0.1 2.9

Flagg Ranch to Colter Bay Roadway 49.8 0 13.3 31.1 0.4 0.1 5.3

Mammoth to NE Entrance Roadway 0 0 26.5 66.9 0.5 0 6.1

SM = snowmobile, SC = snowcoach, AM = automobile, LT = light truck, HT = heavy truck, TB = tour bus, SV = shuttle

van.
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ENVIRONMENTAL CONSEQUENCES

274

Table 81. Maximum 24-hour average PM10 concentrations for alternative B.

Location

24-hr Maximum

Concentration

(w/o Background)

(μg/m3)

24-hr Maximum

Concentration

(w/Background)

(μg/m3)

Change

Relative to

Alternative A

(w/o Background)

(%)

West Yellowstone Entrance 0.63** 23.63 98.6

West Entrance to Madison Roadway 0.63** 23.63 94.1

Old Faithful Staging Area 0.12 5.12 81.3

Flagg Ranch Staging Area 0.18 5.18 72.2

Flagg Ranch to Colter Bay

Roadway 0.63** 5.63 33.3

Mammoth to NE Entrance Roadway 0.32** 5.32 0

** Estimated from the modeled maximum 1-hour average concentration based on the persistence formula

 Ct2 = Ct1*(t1/t2)^0.365 (Cooper and Alley 1990).

Table 82. Vehicle contribution to PM10 concentrations for alternative B.

Contribution (%)

Location SM SC AM LT HT TB SV

West Yellowstone Entrance 0 0 3.5 6.7 44.3 27.5 18.0

West Entrance to Madison Roadway 0 0 6.8 13.4 28.2 15.7 35.8

Old Faithful Staging Area 97.0 0 0 0 1.5 1.4 0

Flagg Ranch Staging Area 98.3 0 0 0 1.1 0.6 0

Flagg Ranch to Colter Bay Roadway 36.3 0 11.0 21.3 21.4 6.4 3.6

Mammoth to NE Entrance Roadway 0 0 22.5 46.6 26.7 0 4.2

SM = snowmobile, SC = snowcoach, AM = automobile, LT = light truck, HT = heavy truck, TB = tour bus, SV = shuttle

van.

Effects on Public Safety

Alternative B proposes several actions that would reduce accident potential and improve

safety conditions in the parks. The addition of an aggressive safety and enforcement

program would provide moderate improvements to the safety of all three park units.

Many visitors currently express concern over the unsafe behavior of other winter visitors,

particularly those riding snowmobiles (Friemund 1996). Novice or rental snowmobile

riders accounted for over 85% of all snowmobile accidents (1995-98). An aggressive

safety program, particularly one operated in cooperation with gateway communities,

would allow park personnel to reach more novice snowmobile riders and thereby reduce

the potential for snowmachine accidents.

The implementation of nighttime (11 P.M. to 5 A.M.) travel restrictions in the parks

would eliminate motor vehicle incidents during this time. The effect on public safety

from this action would be negligible because less than 1% of recorded motor vehicle

accidents have occurred between these hours.
IMPACTS OF IMPLEMENTING ALTERNATIVE B

275

Current road conditions are cited as contributing factors in about 16% of snowmobile

accidents in YNP. Improved road and trail conditions would be expected to decrease

accident rates. Eliminating travel on a freshly groomed route allows the surface to

harden, improving its quality. Since the majority of road grooming in YNP is performed

in the early evening, late night closures would have a negligible effect on the current

quality of the groomed surface.

In YNP alternative B proposes plowing the road segments between West Yellowstone

and Old Faithful and would implement a shuttle bus system as the primary mode of

visitor access on this route. This action would provide moderate benefits to public safety

because shuttle bus drivers would have greater familiarity with winter driving conditions,

and local wildlife movements and the overall numbers of vehicle miles traveled per day

on these road segments would be greatly reduced. However, conflict between wheeledvehicles would be anticipated, and the potential for vehicle-animal collisions would be

greater under this alternative than under the no action alternative (see Chapter III, Motor

Vehicle Accidents — YNP).

Depending on weather conditions, the plowed road from the West Entrance to Old

Faithful would greatly improve ambulance response times to Madison and Old Faithful.

Relocating the CDST in GTNP to a new pathway between Moran and Flagg Ranch

would eliminate the potential for inter-modal conflicts along that stretch of road and

alleviate expressed concern about safety regarding this arrangement. Phasing out

snowmobile use on Jackson Lake would eliminate the potential there for snowmobilerelated incidents. Closing the Teton Park Road to snowmobiles would eliminate the

potential for accidents involving co-located skiers and snowmobiles.

Conclusion

Overall, implementation of this alternative would result in moderate beneficial

improvements to public safety in YNP primarily due to the implementation of a mass

transit system between the West Entrance and Old Faithful, an aggressive safety

information and enforcement program, and a shorter response time for EMS to the

Madison and Old Faithful areas. These improvements would affect employees and

visitors.

Implementation of this alternative would result in moderate beneficial improvements to

public safety in GTNP due to increased safety information and an enforcement program,

reduction of inter-modal conflicts, separation of uses, and elimination of snowmobile

conflicts on Jackson Lake. These impacts would affect employees and visitors.

Effects on Geothermal Features

In alternative B, areas of winter visitor access are the same as described in alternative A,

The effects of winter access to geothermal features are similar to those described in

alternative A with the following exceptions.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

276

The additional public awareness that would result from increased interpretive

opportunities would provide beneficial improvements to the protection of geothermal

resources.

The longer winter visitor season (from early December through mid-March) on the road

from West Yellowstone to Madison and Madison to Old Faithful would increase the

number of visitors in the geothermal basins along the Madison to Old Faithful road

segment and at Old Faithful. This increased use and access would cause a corresponding

increase in the likelihood of adverse impacts on the geothermal resources in this area.

Plowing the road from Old Faithful to West Yellowstone would afford park managers

some discretion when identifying the location of plowed pullouts and shuttle bus stops.

This action would provide a minor amount of additional protection to geothermal

resources along these road segments. Similarly, backcountry travel restrictions may

indirectly improve the protection of geothermal features. All backcountry travel under

this alternative would be restricted to designated trails in wildlife winter range, which

includes geothermal areas. This restriction would benefit geothermal features since offtrail travel would not be allowed and managers would only designate winter travel routes

that are away from sensitive areas.

If the adaptive management provisions (research and monitoring) of this alternative

indicate that winter visitor use is causing direct long-term impacts to geothermal features,

then those impacts must be mitigated or the features would be closed to visitors. The

adaptive management provisions of this alternative provide major long-term benefits to

the protection of geothermal resources.

Conclusion

An increase in winter visitation would result in minor adverse impacts on geothermal

features near roads, staging, and destination areas. Minor adverse impacts may occur in

other geothermal areas accessed by groomed roads and nonmotorized trails. These

impacts may be long term. Some mitigation of the described impacts would occur

through increased interpretation and winter backcountry-use restrictions. All geothermal

features would be protected through the monitoring and scientific studies provisions of

this alternative. If adverse impacts occur that cannot be mitigated, the geothermal feature

or resource would be closed to visitor use. The short-term impacts on geothermal

resources would be minor and adverse. Although some long-term adverse impacts may

occur on individual features, the overall protection to these resources provided by this

alternative is moderate to major and beneficial.

Water and Aquatic Resources

The potential for risk of pollutants, as described in alternative A, entering surface and

subsurface waters would increase as the number of snowmobiles increase along the

Canyon Village to Fishing Bridge “high” risk road segment. The risk to water quality
IMPACTS OF IMPLEMENTING ALTERNATIVE B

277

would decrease along the Madison to Norris and Madison to Old Faithful “high” risk

road segments with the decrease or prohibition of snowmobiles on those segments.

The potential for risk of pollutants entering surface water from “medium” risk road

segments would increase on the Mammoth to Norris, Fishing Bridge to East Entrance,

Fishing Bridge to West Thumb, Old Faithful to West Thumb, and West Thumb to Flagg

Ranch segments as the number of snowmobiles increased.

The potential for risk of pollutants entering surface water from the “low” risk Norris to

Canyon and Teton Park Road segments would decrease with the decrease or prohibition

of snowmobiles on that segment.

There would be no change along the remaining road segments.

Table 8334. Snowmachines and associated risk levels for alternative B.

Impact: Daily Vehicle

Miles Traveled Along

the Segment in Alt. A*

Impact: Daily Vehicle

Miles Traveled Along

the Segment in Alt. B*

Road Segment

Risk ±

Rating SM SC SM SC

Mammoth to Norris Medium 641 69 1176 63

West Entrance to Madison Medium 7759 127 0 0

Madison to Norris High 3458 73 588 70

Norris to Canyon Village Low 2214 47 672 48

Canyon Village to Fishing Bridge High 2370 50 3872 48

Fishing Bridge to East Entrance Medium 983 0 1809 0

Fishing Bridge to West Thumb Medium 2627 55 5208 63

Madison to Old Faithful High 7818 165 0 0

Old Faithful to West Thumb Medium 3560 73 5746 68

West Thumb to Flagg Ranch Medium 4219 103 7728 96

Grassy Lake Road High 184 0 200 0

Flagg Ranch to Colter Bay Low 379 0 400 0

Colter Bay to Moran Junction High 248 0 250 0

Moran Junction to East Entrance Medium 49 0 50 0

Teton Park Road Low 156 0 0 0

Moose-Wilson Road Low 6 0 6 0

 

34 *SM = Snowmobile, SC = Snowcoach; The source of pollutants is emissions from snowmobiles, which produce

(conservatively) ten times as many emissions per mile as most wheeled vehicles. Single snowcoaches produce fewer

emissions then single snowmobiles.

±High = within 100 meters of aquatic system on 76% to 100% of the road segment; Medium = within 100 on 51% to 75%

of the road segment; Low risk segments are within 100 meters of rivers less than 50%.
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278

Conclusion

Deposition into snowpack would continue to occur from 2-stroke engine emissions along

groomed park roads in YNP and GTNP. The effect of this deposition on water quality is

undetermined but there is currently no evidence of measurable changes in water quality

or effects on aquatic resources. It is possible that accumulations of pollutants in aquatic

systems may have adverse impacts on wetlands and aquatic resources downstream from

high-risk road segments. Oversnow vehicle use in this alternative involves localized high

risk to surface water quality, but reduces oversnow vehicle-miles traveled along high risk

road segments in the three park units by about 65%. Snowmobile and snowplane use on

Jackson Lake would continue the risk of moderate to major adverse impacts on water

quality in that water body. The phasing out of snowmobile use on Jackson Lake would

in time reduce the sources of pollution by half. Minor short-term water quality and

wetland impacts would occur along the eastern side of US 89/287 as a result of new

pathway construction.

Mitigation

The new year-round pathway would be designed and sited to minimize impacts to all

park resources including wildlife, vegetation, and wetlands. Any impacts to wetlands

would be minimized and mitigated in accordance with NPS Wetland Guidelines. Any

needed bridges would be designed to complement, not impact, floodplains in accordance

with NPS Floodplain Management Guidelines. The use of bio-based fuels by the NPS

and the availability of fuels in gateway communities may result in a minor decrease in

pollutant deposition into snow. Best management practices would be utilized during the

construction, reconstruction, or winter plowing of trails and roads to prevent unnecessary

vegetation removal, erosion, and sedimentation. The release of snowpack contaminants

into surface water could be mitigated by disconnecting snowmelt drainages from trails

used by oversnow vehicles. Any new or reconstructed winter-use sanitary facilities

would be constructed in locations and using advanced technologies that would protect

water resources. A focused program of monitoring would reduce the uncertainty of

impacts from oversnow vehicles, and if necessary, indicate best management practices

that might be implemented.

Effects on Wildlife

Ungulates

Effects of groomed roads and trails. Packed trails may influence wildlife movements

and distributions by facilitating travel into wildlife areas that would normally be

inaccessible due to deep snow. Under alternative B, YNP would groom about 160 miles

of road surface for use by oversnow motorized vehicles (24 less than under alternative A)

and 47 miles for nonmotorized use (10 more than under alternative A). GTNP and the

Parkway would groom about 36 miles, the same as alternative A.

In YNP effects related to packed trails would be reduced relative to alternative A.

Effects in GTNP would remain the same.
IMPACTS OF IMPLEMENTING ALTERNATIVE B

279

Effects of motorized oversnow use of groomed and ungroomed roads and trails. The

use of motorized oversnow vehicles can cause injury and death to wildlife, especially in

poor lighting conditions and during snowfall, and can cause displacement from preferred

habitats. Under alternative B, these effects would be associated with 160 miles of

groomed oversnow motorized roads in YNP (24 less than current management); GTNP

would maintain 36 miles of groomed motorized routes (the same as currently) and 11

miles of ungroomed motorized routes (24 miles less than current management).

Because the use of oversnow motorized vehicles would be reduced in the parks under

alternative B, overall associated effects would be reduced with the exception of the routes

from Moran to Flagg Ranch and Grassy Lake Road in GTNP. The separation of the

CDST from the plowed roadway would cumulatively increase collision and displacement

impacts associated with the use of both oversnow and wheeled-vehicles.

Effects of plowed roads. Road plowing may cause habitat fragmentation by creating

structural barriers (i.e., snow berms) to ungulate movements (Aune 1981). In addition

plowed roads, like groomed roads, may also provide an energy efficient mechanism for

wildlife movements, including bison, elk, and moose. Under alternative B, the effects

described above are associated with about 106 miles of plowed road in YNP, an increase

of 30 miles over existing management. The road would be open to mass transit vehicles

and about 40 private vehicles, with no late night traffic allowed. GTNP, including the

Parkway, would continue to maintain about 100 miles of plowed road, the same as under

current management.

In YNP the plowed road from West Entrance to Old Faithful would result in more snow

berms, thus potentially increasing fragmentation along this segment. An increase in

ungulate use of the plowed road as compared to the currently groomed road is not

expected because plowed roads do not offer additional energy savings over groomed

roads. The effects of plowed roads in GTNP would be the same as those described in

alternative A.

All other potential impacts would be the same as stated in alternative A.

Effects of motorized use of plowed roads. The effects of plowed roads are similar to

those of groomed roads, except that the magnitude of the effect is usually greater. The

use of motorized vehicles on plowed roads can cause injury and death for wildlife,

especially in poor lighting conditions, at dusk and dawn, and during snowfall, and can

cause displacement from preferred habitats.

The use of plowed roads by wheeled-vehicles may increase wildlife-vehicle collisions

over current rates along the road segment from West Yellowstone to Old Faithful. The

limitation on late night travel (11 P.M. to 5 A.M.) and the use of NPS-managed shuttle

busses with trained drivers will help to mitigate collision impacts. According to Gunther

et al. (1998) no collisions have occurred between busses and ungulates in the park.
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ENVIRONMENTAL CONSEQUENCES

280

Displacement of ungulates from preferred habitats along the West Yellowstone to Old

Faithful route would be reduced relative to alternative A because vehicle numbers would

be reduced, and traffic would be more predictable and less dispersed.

Effects of nonmotorized use of groomed and designated ungroomed routes. The

primary effects of nonmotorized use on ungulates are displacement from preferred

habitats, especially geothermal areas that are important for winter survival in YNP, and

increased energy expenditures, including physiological stress, which may reduce

individuals’ chances of survival. Under alternative B, YNP increases nonmotorized

opportunities from 37 to 47 miles of groomed nonmotorized routes, and GTNP and the

Parkway increase ungroomed nonmotorized routes from 26 to 33 miles. Although the

above effects may be increased due to the addition of nonmotorized routes, they are

expected to be relatively minor because most with the exception of short trails in the

Mammoth Hot Springs and Blacktail Plateau areas, would not be located in critical

ungulate winter range.

Effects of unregulated backcountry nonmotorized use. Unregulated backcountry

nonmotorized use is more random and infrequent relative to nonmotorized use on

designated routes. Consequently, although encounters between backcountry users and

ungulates may only occur sporadically, they can be especially disturbing and lead to

additional energy expenditure and stress that reduces animals’ chances of survival and

reproduction. Alternative B reduces the potential for these effects in YNP by eliminating

or restricting backcountry use in winter range. Use, where permitted, would be limited to

designated routes where ungulate habitat would not be impacted. Because winter range

in GTNP is relatively limited and already closed to public access in several areas, no new

restrictions on use in this park are proposed under this alternative.

Under alternative B, impacts associated with backcountry use in GTNP would remain the

same as those under alternative A. Moderate to major adverse impacts on bighorn sheep

would continue, as well as potential impacts on moose, elk, and bison on Blacktail Butte

and Wolff Ridge.

Effects of the presence and use of winter support facilities. Increases in human

activity associated with the presence of support facilities may displace species sensitive

to human disturbance. Alternative B proposes an increase in the number and size of

warming huts and other day-use facilities. Warming huts and restrooms would be located

at popular ski trailheads, motorized staging areas, and areas where existing facility size is

currently inadequate or nonexistent (e.g., Tower, Norris, Canyon). Warming huts in the

vicinity of ungulate winter range important to elk, deer, and bison would potentially

increase human use and consequently reduce habitat effectiveness. However, over time,

the predictable nature of the recreation expected to occur in the area may allow species to

habituate to the increase in human activity. The effects of these huts on ungulates would

be the same for all alternatives.
IMPACTS OF IMPLEMENTING ALTERNATIVE B

281

Federally Protected Species

Effects of groomed roads and trails. Packed trails may influence wildlife movements

and distributions by facilitating travel for wildlife into areas that would normally be

inaccessible due to deep snow. Under alternative B, YNP would groom about 160 miles

of road surface for use by oversnow motorized vehicles (24 less than under alternative A)

and 47 miles for nonmotorized use (10 more than under alternative A). GTNP and the

Parkway would groom about 36 miles, the same as alternative A.

In YNP effects related to packed trails would be slightly reduced from those under

alternative A. Effects in GTNP would remain the same. The parks may close any area if

warranted to protect federally protected species.

Effects of motorized use of groomed and ungroomed roads and trails. The use of

motorized oversnow vehicles can cause displacement from preferred habitats. Mortality

caused by collisions with snowmobiles or snowcoaches has not occurred for any of these

species. Under alternative B, these effects would be associated with 160 miles of

groomed oversnow motorized roads in YNP (24 less than current management); GTNP

would maintain 36 miles of groomed motorized routes, the same as current management,

and 11 miles of ungroomed motorized routes, 24 miles less than current management.

Because the use of oversnow motorized vehicles would be reduced in the parks under

alternative B, overall associated effects would be reduced with the exception of the route

from Moran to Flagg Ranch in GTNP. The separation of the CDST from the plowed

roadway would cumulatively increase displacement impacts associated with the use of

both oversnow and wheeled-vehicles. Canada lynx and wolves may be affected along

this route.

Effects of plowed roads. Road plowing may cause habitat fragmentation by creating

structural barriers (i.e., snow berms) to wildlife movements (Aune 1981). Similar to

groomed roads, plowed roads may influence wildlife movements and distributions by

facilitating travel for wildlife into areas that would normally be inaccessible due to deep

snow. Under alternative B, the effects described above are associated with about 106

miles of plowed road in YNP, an increase of 30 miles over existing management. The

road would be open to mass transit vehicles and about 40 private vehicles, with no late

night traffic allowed. GTNP including the Parkway would continue to maintain about

100 miles of plowed road, the same as under current management.

Under alternative B, impacts related to plowed roads would slightly increase in YNP as

compared to alternative A. The road from West Yellowstone to Old Faithful would be

plowed and open to public access two weeks earlier under this alternative, potentially

leading to an increase in human-bear interactions during the pre-breeding period.

However, none of the radio-collared bears in YNP have denned along this road segment,

and only about 10% of bears are still active at this time (Haroldson et al. In prep).

Effects related to plowed roads in GTNP would remain the same as under current

management.
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ENVIRONMENTAL CONSEQUENCES

282

Effects of motorized use of plowed roads. The effects of traffic on plowed roads are

similar to those of traffic on groomed roads, except that the magnitude of the effect is

usually greater. The use of motorized vehicles on plowed roads can cause injury and

death for wildlife, especially in poor lighting conditions, at dusk and dawn, and during

snowfall, and can cause displacement from preferred habitats.

Under alternative B, impacts related to plowed roads would slightly increase in YNP as

compared to alternative A. The limitation on late night travel (11 PM to 5 AM) and the

use of NPS-managed shuttle busses with trained drivers will help to mitigate collision

impacts. In GTNP the separation of the CDST from the plowed roadway would

cumulatively increase displacement impacts associated with the use of both oversnow

and wheeled-vehicles. Canada lynx and wolves may be affected along this route.

Effects of nonmotorized use on groomed and designated ungroomed routes. The

primary effects of nonmotorized use on wildlife are displacement from preferred habitats

and increased energy expenditures, including physiological stress, which may reduce

individuals’ chances of survival. Under alternative B, YNP increases nonmotorized

opportunities from 37miles to 47 miles of groomed nonmotorized routes, and GTNP and

the Parkway increase ungroomed nonmotorized routes from 26miles to 33 miles.

Although the above effects may be increased due to the addition of nonmotorized routes,

they are expected to be negligible because most routes, with the exception of short trails

in the Mammoth Hot Springs and Blacktail Plateau areas, would not be located in critical

ungulate winter range, and consequently the species that prey upon ungulates or consume

their carcasses would not be affected. Furthermore, when warranted, the parks may close

any area where federally protected species are observed.

Effects of unregulated backcountry nonmotorized use. Unregulated backcountry

nonmotorized use is more random and infrequent relative to nonmotorized use on

designated routes. Consequently, although encounters between backcountry users and

federally protected wildlife species may only occur sporadically, they may cause

displacement and additional energy expenditure and stress that reduces animals’ chances

of survival and reproduction. Alternative B minimizes the potential for these effects in

YNP by eliminating or restricting backcountry use in winter range. Use, where

permitted, would be limited to designated routes where ungulate habitat would not be

impacted. Because winter range in GTNP is relatively limited and already closed to

public access in several areas, no new restrictions on use in this park are proposed under

this alternative.

Impacts related to backcountry use under alternative B would be reduced as compared to

current management in YNP. Impacts in GTNP would remain the same.

Presence and use of winter support facilities. Warming huts and campgrounds can

cause habituation in some wildlife species by the presence of human food and garbage,

and can lead to human-wildlife conflicts. In addition increases in human activity
IMPACTS OF IMPLEMENTING ALTERNATIVE B

283

associated with the presence of support facilities may displace species sensitive to human

disturbance. Alternative B proposes an increase in the number and size of warming huts

and other day-use facilities. Warming huts and restrooms would be located at popular ski

trailheads, motorized staging areas, and areas where existing facility size is currently

inadequate or nonexistent (e.g., Tower, Norris, and Canyon).

A major problem associated with human development in occupied bear habitat is the

availability of food attractants. Bears that become conditioned to human foods and

garbage are often the targets of management actions, including lethal control. High

winter visitor use has contributed to a garbage problem in YNP as garbage that has

accumulated throughout the winter may attract hungry grizzly bears in the spring. To

date, YNP does not have adequate winter garbage storage facilities but will rectify this

issue by constructing a winter garbage storage facility that is wildlife-proof in the Old

Faithful, Grant, Lake, and Canyon areas (a feature of all alternatives). In addition under

alternative B, the availability of a plowed road into the park’s interior would allow for the

removal of garbage, thus decreasing problems associated with habituation.

Compared to current management, impacts related displacement would be greater due to

the increase in number of facilities. Specifically, huts located in thermally influenced

ungulate winter range could displace ungulates, and thus affect the availability of bison

and elk carcass, important spring foods for grizzly bears. Because ungulates have been

known to habituate to predictable human activities any displacement would most likely

be short term. In addition as stated previously, the majority of bears do not emerge from

hibernation until after the winter use season at which time the Bear Management Area

restrictions will be in affect to allow bears uninterrupted use of spring carcass habitats in

known winter ranges. Areas of high bear use may be closed at any time according to

park policy.

Species of Special Concern.

Effects of groomed roads and trails. Packed trails may influence wildlife movements

and distributions by facilitating travel for wildlife into areas that would normally be

inaccessible due to deep snow; inhibiting foraging activities of carnivores that tunnel

beneath the snow to hunt subnivian prey; and reducing subnivian prey availability by

increasing mortality of these small mammals. Under alternative B, YNP would groom

about 160 miles of road surface for use by oversnow motorized vehicles (24 less than

under alternative A) and 47 miles for nonmotorized use (10 more than under alternative

A). GTNP and the Parkway would groom about 36 miles, the same as alternative A.

In YNP effects related to packed trails would be slightly reduced from those under

alternative A. Effects in GTNP would remain the same. The parks may close any area if

warranted to protect federally protected species.

Effects of motorized oversnow use of groomed and ungroomed roads and trails. The

most likely impacts to park species of special concern are displacement from preferred
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ENVIRONMENTAL CONSEQUENCES

284

habitats and degradation of the aquatic environment from pollutants in the snowpack.

Documented mortality caused by collisions with oversnow vehicles in the parks is rare.

In ten years only one of these species (a marten) was reportedly killed by a snowmobile

in YNP (Gunther et al. 1998). Under alternative B, these effects would be associated

with 160 miles of groomed oversnow motorized roads in YNP, 24 miles less than current

management; GTNP would maintain 36 miles of groomed motorized routes and 11 miles

of ungroomed motorized routes, 24 miles less than current management.

Because the use of oversnow motorized vehicles would be reduced in the parks under

alternative B, overall associated effects would be reduced with the exception of the routes

from Moran to Flagg Ranch and Grassy Lake Road in GTNP. The separation of the

CDST from the plowed roadway would cumulatively increase displacement impacts

associated with the use of both oversnow and wheeled-vehicles.

See Water and Aquatic Resources, Chapter IV for an assessment of the impacts of

exhaust on water quality in the parks.

Effects of plowed roads. Similar to groomed roads, plowed roads also provide an

energy efficient mechanism for wildlife movements. Under alternative B, the effects

described above are associated with about 106 miles of plowed road in YNP, an increase

of 30 miles over existing management. The road would be open to mass transit vehicles

and a small number of about 40 private vehicles, with no late night traffic allowed.

GTNP, including the Parkway, would continue to maintain about 100 miles of plowed

road, the same as under current management.

Under alternative B, impacts related to plowed roads would slightly increase in YNP as

compared to alternative A. Effects related to plowed roads in GTNP would remain the

same as under current management.

Effects of motorized use of plowed roads. The most likely impact to park species of

special concern is displacement from preferred habitats and mortality caused by

collisions.

Under alternative B, impacts related to plowed roads would slightly increase in YNP as

compared to alternative A. In particular, swans that winter in open water habitats along

the plowed road from the West Entrance of YNP to Old Faithful may be disturbed by the

increase in wheeled-vehicle traffic along this route. In GTNP the separation of the CDST

from the plowed roadway would cumulatively increase displacement impacts associated

with the use of both oversnow and wheeled-vehicles.

Effects of nonmotorized use on groomed and ungroomed designated routes. The

primary effects of nonmotorized use are displacement from preferred habitats, and

increased energy expenditures, including physiological stress, which may reduce

individuals’ chances of survival. Under alternative B, YNP increases nonmotorized

opportunities from 37miles to 47 miles of groomed nonmotorized routes, and GTNP and
IMPACTS OF IMPLEMENTING ALTERNATIVE B

285

the Parkway increase ungroomed nonmotorized routes from 26miles to 33 miles.

Although the above effects may be increased due to the addition of nonmotorized routes,

they are expected to be relatively minor because most routes would not be located in

areas critical to species of special concern (e.g., adjacent to open water habitats and

ungulate winter ranges).

Unregulated backcountry nonmotorized use. Unregulated backcountry nonmotorized

use is more random and infrequent relative to nonmotorized use on designated routes.

Consequently, although encounters between backcountry users and species of special

management concern may only occur sporadically, they can be especially disturbing and

lead to additional energy expenditure and stress that reduces animals’ chances of survival

and reproduction. Alternative B minimizes the potential for these effects in YNP by

eliminating or restricting backcountry use in important winter habitats (e.g., thermally

influenced areas). Use, where permitted, would be limited to designated routes. Because

winter habitats in GTNP are already closed to public access in several areas, no new

restrictions on use in this park are proposed under this alternative.

Impacts related to backcountry use in under alternative B would be reduced as compared

to current management in YNP. Impacts in GTNP would remain the same as under

alternative A.

Presence and use of winter support facilities. The primary effects of warming huts and

campgrounds on park species of special concern are associated with increases in human

activity and the subsequent disturbance and displacement of species or their prey.

Alternative B proposes an increase in the number and size of warming huts and other

day-use facilities. Warming huts and restrooms would be located at popular ski

trailheads, motorized staging areas, and areas where existing facility size is currently

inadequate (e.g., Tower, Norris, and Canyon).

Compared to current management, impacts related to displacement would be greater due

to the increase in number of facilities. Specifically, huts located in thermally influenced

ungulate winter range could displace ungulates, and thus affect bison and elk carcass

availability for wolverines, fishers, and marten. Because ungulates have been known to

habituate to predictable human activities any displacement would most likely be short

term. Impacts to other species of special concern would be the same as those under

alternative A.

Conclusion

All effects described above and summarized in this section would be short term in nature.

Effects associated with groomed roads and snowmobiles would decrease in YNP, but

would remain a concern in GTNP due to the separation of the CDST from the road

shoulder. Effects related to wheeled-vehicles in YNP would increase but would be

mitigated through the use of mass transit and restrictions on travel in the evenings.

Another important component for wildlife is the implementation of closures and
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ENVIRONMENTAL CONSEQUENCES

286

restrictions in certain backcountry wildlife winter ranges in YNP. Adaptive management

may be employed to adjust management if and when impacts to wildlife are determined.

Further mitigation would be afforded by an increased emphasis on visitor education and

interpretive opportunities, as well as increased administrative capability.

Although impacts to populations resulting from winter recreation are neither long term

nor very significant, impacts to individual members of the population can be important,

leading to death either directly from collisions or continued harassment, or indirectly

through management actions as a response to habituation to human presence and food.

Although concerned about impacts to individuals, for the most part (with the exception of

federally protected species), the NPS bases management actions on the protection of

populations of native animals. For example, see NPS 77, Natural Resources

Management, Chapter II.

Ungulates

• Effects of groomed roads and trails on animal movements — unknown if and to what

extent beneficial effects outweigh negative effects. Effects are reduced from alternative A

in YNP and remain the same in GTNP.

• Effects of motorized oversnow use of groomed and ungroomed roads and trails on: 1)

mortality caused by collisions –less than alternative A for YNP, greater than alternative A

for GTNP due to the separation of the CDST from the road shoulder; and 2) displacement

from preferred habitats less than alternative A for YNP, greater than alternative A for

GTNP due to the separation of the CDST from the road shoulder.

• Effects of plowed roads on: 1) habitat fragmentation – more than alternative A for YNP,

same as alternative A for GTNP; and 2) animal movements – unknown if and to what

extent beneficial effects outweigh negative effects — same as alternative A.

• Effects of motorized use of plowed roads on: 1) mortality caused by collisions – more than

alternative A for YNP, same as alternative A for GTNP; and 2) displacement from

preferred habitats – less than alternative A for YNP, same as alternative A for GTNP.

• Effects of nonmotorized use of groomed and designated ungroomed routes on displacement

from preferred habitats – slighter greater than alternative A.

• Effects of unregulated backcountry nonmotorized use on displacement from preferred

habitats – less than alternative A for YNP, same as for GTNP. Impacts to bighorn sheep in

GTNP would remain moderate to major and long term if no mitigation is applied.

• Effects of the presence and use of winter support facilities on displacement. Effects may

be increased relative to alternative A because more huts are proposed.

Federally Protected Species

• Effects of groomed roads and trails on animal movements: 1) bald eagles, grizzly bears,

and wolves — same as alternative A; and 2) lynx – less than alternative A.

• Effects of motorized oversnow use of groomed and ungroomed roads and trails on

displacement from preferred habitats – less than alternative A with the exception of the

CDST/plowed road segment which would be greater than alternative A; excluding the

grizzly bear which, for the most part, will not be active during the winter use season.

• Effects of plowed roads on: (1) habitat fragmentation – all species, more than alternative A

for YNP, same as alternative A for GTNP; and 2) animal movements – all species, no

known effect.

• Effects of motorized use of plowed roads on: 1) mortality caused by collisions – bald

eagles and grizzly bears, more than alternative A for YNP, same as for GTNP; wolves,

more than alternative A for YNP, same as for GTNP; lynx, same or more than alternative A

for all parks; and 2) displacement from preferred habitats – bald eagles, more than
IMPACTS OF IMPLEMENTING ALTERNATIVE B

287

alternative A for YNP, no effect on grizzly bears; no known effect to date on wolves and

lynx.

• Effects of nonmotorized use of groomed and designated ungroomed routes on displacement

from preferred habitats – adverse, negligible, and short term on bald eagles; no effect on

grizzly bears; no known effect to date on wolves and lynx. Effects may slightly increase

relative to alternative A.

• Effects of unregulated backcountry nonmotorized use on displacement from preferred

habitats – adverse, minor, and short term on bald eagles; adverse, negligible, and short term

on grizzly bears; adverse, minor, and short term on wolves; no known effect to date on

lynx. These effects would be less than alternative A for YNP, same as alternative A for

GTNP.

• Effects of the presence and use of winter support facilities on displacement – no affect on

bald eagles; adverse, negligible, and short term on grizzly bears, with mitigation; adverse,

minor, and short term on wolves; no effect on lynx. Effects may be slightly increased

relative to alternative A because more huts are proposed.

Species of Special Concern

• Effects of groomed roads and trails on 1) animal movements – no known effect on

wolverines; adverse, negligible, and short term on fishers and martens; no effect on otters,

swans, reptiles, amphibians, and fish; 2) foraging activities – adverse, negligible, short term

on marten; no effect on the other species; and 3) subnivian prey availability — adverse,

negligible, and short term on marten; no effect on the other species. May be a slight

reduction relative to alternative A for YNP; effects would remain the same for GTNP.

• Effects of motorized oversnow use of groomed and ungroomed roads and trails on

displacement – no known effect on wolverine; adverse, negligible, and short term on

fishers and marten; no effect on otters, reptiles, amphibians, and fish; adverse, minor, short

term on swans. May be a slight reduction relative to alternative A for YNP; effects may

increase in GTNP due to removing the CDST from the road shoulder.

• Effects of plowed roads on animal movements – no known effect on wolverines, fishers,

and martens; no effect on otters, swans, reptiles, amphibians, and fish. If effects did occur,

they would increase in YNP relative to alternative A.

• Effects of motorized use of plowed roads on 1) displacement from preferred habitats –

adverse, negligible, short term on wolverines, fishers, martens; no effect on otters, swans,

reptiles, amphibians, and fish and 2) mortality from collisions — adverse, negligible, and

short term on otters and martens; no effect to date on other species. Effects may increase

relative to alternative A in YNP.

• Effects of nonmotorized use of groomed and designated ungroomed routes on displacement

from preferred habitats – no effect on wolverines; no known effect on fishers, martens, and

otters; adverse, minor, and short term on swans; adverse, negligible, and short term on

sagebrush lizard; no effect on rubber boa, amphibians, and fish. Effects may slightly

increase relative to alternative A.

• Effects of unregulated backcountry nonmotorized use on displacement from preferred

habitats – adverse, negligible, and short term on wolverines and sagebrush lizard; no

known effect on fishers, martens, and otters; adverse, minor, and short term on swans; no

effect on rubber boa, amphibians, and fish. Effects decrease relative to alternative A in

YNP, and may increase in GTNP.

• Effects of the presence and use of winter support facilities on displacement of potential

prey (carcass) availability – adverse, minor, and short term on wolverines, fishers, and

martens; no effect on swans, rubber boa, amphibians, and fish; no known effect on otters;

adverse, minor, and short term on sagebrush lizard. Effects may be slightly increased

relative to alternative A because more huts are proposed.

Mitigation

• Closures around known dens and nests would continue to be implemented.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

288

• The monitoring and evaluation of backcountry nonmotorized use in GTNP should be

enhanced and closures should be implemented as warranted.

• Ramps or pullouts for moose to exit plowed roads to reduce collisions between

snowmobiles and moose along the CDST would be provided.

• Use of groomed and plowed surfaces by bison and other ungulates would continue to be

monitored.

• Snow track surveys for carnivores, including lynx, on both groomed and ungroomed routes

would be conducted.

Effects on Natural Soundscape

Audibility analysis — combined effects of all wheeled and oversnow vehicles

Table 84 presents the acres of park land by road segment where any wheeled or

oversnow vehicle noise would be audible under the two background conditions,

“average” and “quiet,” as defined in the Assumptions and Methodologies section of this

chapter. For each background condition, acreage is presented for three categories of

audibility: (1) audible for any amount of time (labeled “audible at all”); (2) audible for

10% of the time or more; and (3) audible for 50% of the time or more. Appendix M

contains tables with distances to audibility for each segment for each alternative.

Alternative B features plowing the road from the West Entrance of YNP to Old Faithful;

use of “clean and quiet” snowmobile and snowcoach (based on a 70 dBA noise emission

level at 50 feet); elimination of snowmobiles on Teton Park Road; and phasing out of

snowmobiles (but not snowplanes) on Jackson Lake. This alternative also requires that

all snowplanes on Jackson Lake meet the current regulated limit of 86 dBA at 50 feet.

The results for alternative B show that for the “average” background sound level,

wheeled or oversnow vehicles would be audible to some degree for over 138,000 acres in

the three park units. For over 59,000 of those acres, wheeled or oversnow vehicles would

be audible for at least 10% of the time during the day. For over 14,000 of those acres,

they would be audible for at least half of the time during the day. These acreage totals

increase by 8% to 15% for the “quiet” background conditions.

The “clean and quiet” requirement results in reduced audibility acreage over all segments

that carry oversnow vehicles. These reductions are less evident when looking at the

totals because of large contribution from the segment from Moran Junction to the South

Entrance of GTNP for all three audibility categories, acreage that remains almost

constant for all of the alternatives. For example, over 75% of the acreage for the “audible

50% or more” categories is along this segment.

The other key segments for the “audible 50% or more” categories are from Fishing

Bridge to West Thumb, from West Thumb to Flagg Ranch, and from Canyon Village to

Fishing Bridge, although all are significantly reduced compared to the no action

alternative.

The audibility acreage is greatly reduced for the West Entrance to Madison and Madison

to Old Faithful segments due to the replacement of oversnow vehicles with wheeled-
IMPACTS OF IMPLEMENTING ALTERNATIVE B

289

vehicles on the plowed road. Likewise the, elimination of snowmobiles, on Teton Park

Road reduces its audibility acreage to zero.

The plowed road from Mammoth to the Northeast Entrance is a major contributor to the

“audible at all” acreage (and, to a lesser extent, “audible 10% or more”). This impact

remains virtually unchanged across all the alternatives, somewhat makes the beneficial

impacts of reduced sound from oversnow motorized vehicles.

Snowplanes and snowmobiles on Jackson Lake are also major contributors to the

“audible at all” categories, although the acreage is greatly reduced over the no action

alternative because of the sound level restrictions on both machines and the phasing out

of snowmobiles.

Average Sound Level Analysis

To give a sense of the effect of the number of oversnow or wheeled-vehicles on a road

segment, and their speed and sound level, Table 85 shows the computed hourly

equivalent or “average” sound level (Leq) over the daytime period. Levels are shown for

each road segment at two distances, 100 feet and 4,000 feet, and for both open and

forested terrain. These hourly Leq values do not have the background sound level added

in to them. Also, they cannot be compared against the background levels to assess

audibility, since Leq represents a long-term average of both quiet and loud moments.

The hourly Leq at 100 feet is highest for the segment representing Jackson Lake, plus the

segments from Canyon Village to Fishing Bridge, from Fishing Bridge to West Thumb,

from Old Faithful to West Thumb, and from West Thumb to Flagg Ranch. The segments

from Moran Junction to the GTNP East Entrance and to the GTNP South Entrance would

have the highest Leq at a distance of 4,000 feet away.

There are major 16 dB to 18 dB reductions in the Leq for the West Entrance to Madison

and Madison to Old Faithful segments that would be plowed.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

290

Table 84. Acres of park land affected by vehicles audibility for alternative B.

With Average Background

Conditions

With Quiet Background

Conditions

Road Segment Miles

Audible

at All

Audible

10% of

the Time

or More

Audible

50% of

the Time

or More

Audible

at All

Audible

10% of

the Time

or More

Audible

50% of

the Time

or more

1. Mammoth to Northeast Entrance 47 16,121 5,440 0 16,816 6,337 0

2. Mammoth to Norris 21 8,383 924 0 9,069 1,014 0

3. West Entrance to Madison 14 5,302 1,396 0 5,599 1,632 0

4. Madison to Norris 14 5,203 145 0 5,538 174 0

5. Norris to Canyon Village 12 4,302 0 0 4,540 0 0

6. Canyon Village to Fishing Bridge 16 7,140 5,079 494 7,865 5,559 807

7. Fishing Bridge to East Entrance 27 8,765 1,294 0 9,655 1,416 0

8. Fishing Bridge to West Thumb 21 10,681 7,564 1,378 11,941 8,111 2,019

9. Madison to Old Faithful 16 6,205 1,707 0 6,571 1,979 0

10. Old Faithful to West Thumb 17 6,500 4,707 0 6,976 5,325 0

11. West Thumb to Flagg Ranch 24 10,249 7,105 902 11,038 8,039 998

12. Grassy Lake Road 7.6 2,203 0 0 2,414 0 0

13. Flagg Ranch to Colter Bay 15.6 7,670 2,983 0 8,328 3,279 0

14. Colter Bay to Moran Junction 10.2 4,610 2,331 0 4,959 2,535 0

15. Moran Junction to East Entrance 2 1,201 724 490 1,302 819 534

16. Moran Junction to South Entrance 26 21,714 14,812 11,293 23,842 17,207 11,996

17. Teton Park Road 15 No Veh. No Veh. No Veh. No Veh. No Veh. No Veh.

18. Moose-Wilson Road 2.5 807 0 0 853 0 0

19. Antelope Flats Snowmobile Route No Veh. No Veh. No Veh. No Veh. No Veh. No Veh.

20. Jackson Lake 9.7 10,963 3,326 0 12,280 4,905 0

TOTAL 138,018 59,534 14,558 149,589 68,331 16,355

Conclusion

Alternative B impacts about 75% to 76% of the acreage impacted by the no action

alternative, in terms of time when vehicles would be audible at all. For the 10% and 50%

audibility categories as a group, the acreage drops to about 63% to 64% of that for the no

action alternative. In YNP the 50% time audible acreage drops to only 23% of that for

the no action alternative for average background conditions. The reasons for the

reductions are the use of the 70-dBA “clean and quiet” snowmobiles and snowcoaches,

the replacement of oversnow vehicles with wheeled-vehicles from West Entrance to Old

Faithful, and the elimination of oversnow vehicles on Teton Park Road. In YNP the 50%

time audible acreage drops to only 23% of that for the no action alternative for average

background conditions. For all three audibility categories taken together, alternative B

impacts the second smallest acreage after alternative D.
IMPACTS OF IMPLEMENTING ALTERNATIVE B

291

Table 85. Average hourly Leq from wheeled and oversnow vehicle noise at two distances

to each road segment for alternative B.

Leq at Distance (dBA)

Open Terrain Forested Terrain

Road Segment 100 feet 4,000 feet 100 feet 4,000 feet

1. Mammoth to Northeast Entrance 35 2 33 0

2. Mammoth to Norris 42 3 41 0

3. West Entrance to Madison 38 6 37 0

4. Madison to Norris 42 2 40 0

5. Norris to Canyon Village 43 3 41 0

6. Canyon Village to Fishing Bridge 49 9 47 1

7. Fishing Bridge to East Entrance 43 3 41 0

8. Fishing Bridge to West Thumb 49 9 47 1

9. Madison to Old Faithful 38 6 37 0

10. Old Faithful to West Thumb 50 10 48 2

11. West Thumb to Flagg Ranch 50 10 48 2

12. Grassy Lake Road 39 0 37 0

13. Flagg Ranch to Colter Bay 41 6 40 0

14. Colter Bay to Moran Junction 43 8 41 0

15. Moran Junction to East Entrance 46 12 44 4

16. Moran Junction to South Entrance 46 14 44 6

17. Teton Park Road 0 0 0 0

18. Moose-Wilson Road 31 0 29 0

19. Antelope Flats Snowmobile Route No Veh. No Veh. No Veh. No Veh.

20. Jackson Lake 54 7 52 0

Effects on Cultural Resources

The winter visitor use activities described in this alternative would occur on existing

roads, deep snowpack over frozen ground, or frozen lake surfaces, and not affect known

archeological resources. To ensure that adequate consideration and protection are

accorded potential archeological resources during the construction of visitor services,

such as permanent warming huts, and other day-use facilities, or of trails, archeological

surveys would precede all significant ground-disturbing activities. Archeological

monitoring would occur where less ground disturbance is expected. If previously

undiscovered archeological resources are unearthed during construction activities, all

work in the immediate vicinity of the discovery would be halted until the resources could

be identified and documented and an appropriate mitigation strategy developed, if

necessary. If construction impacts upon archeological sites could not be avoided the

recommended mitigation strategy of site testing and data recovery would be implemented

after consulting with the Wyoming State Historic Preservation Office. Consultation

would ensure that the informational significance of the sites would be preserved.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

292

If permanent warming huts or other day-use facilities are erected either in or near historic

districts or potential cultural landscapes, application of several guidelines would blend

facilities into both the built and natural surroundings of the parks:

1) Sensitive design and location of facilities;

2) Use of appropriate materials and colors in construction; and

3) Select plantings of native vegetation as visual buffers.

If historic structures are adaptively rehabilitated for visitor services, the integrity and

character of each structure’s exterior would be preserved while establishing the most

efficient use of the interior’s available space. All work would be performed in

accordance with the Secretary of the Interior’s Standards for the Treatment of Historic

Properties (1995). Materials removed during rehabilitation of historic structures would

be evaluated to determine their value to the parks’ museum collections or for their

comparative use in future preservation work at the sites. Any corresponding visual,

audible, and atmospheric intrusions associated with increases in visitation would not be

significant enough to alter or diminish the integrity of historic districts or potential

cultural landscapes.

Visual, audible, and atmospheric intrusions would occur in the vicinity of all construction

activities. Such impacts would be temporary and minor.

Though potentially significant cultural landscapes would be protected and preserved,

increased visitor use, resulting from the expansion or construction of visitor facilities and

trailheads and trails, could cause overuse and degradation of contributing landscape

features such as roads, trails, and structures. However, the parks’ enhanced interpretive

and educational programs also would increase visitor appreciation of and sensitivity to

resources, as well as provide an understanding of how to experience resources without

inadvertently damaging them.

The plowing of roads and highways and maintenance of groomed motorized routes

throughout the winter season would have no effect upon roads or road systems that are

either potentially eligible to be listed in the National Register of Historic Places or are

contributing elements of potential cultural landscapes. Existing road contours would be

unaltered.

There would be no adverse impacts to known ethnographic resources.

Conclusion

None of the actions described would adversely impact cultural resources.

Effects on Visitor Access and Circulation

Access

Plowing the roadway segments between West Yellowstone and Old Faithful is the

principal action proposed in alternative B regarding access. West Yellowstone is the
IMPACTS OF IMPLEMENTING ALTERNATIVE B

293

most heavily used gateway community during the winter season and serves as a staging

area for about 61,800 visitors each winter. On average, about 40% of all seasonal visitors

entering through West Yellowstone visit during the month of February. Average nonholiday, daily visitation on weekends during February is about 840 without regard to

mode of transportation. Snowmobile passengers, either on private sleds, rented sleds, or

guided tours, account for about 90% of the visitation through this park access point.

Snowcoach passengers account for the majority of the remaining visitors. Visitor

surveys indicate that about 20% to 30% of visitors ski once in YNP (Littlejohn 1996;

Borrie et al. 1999; Duffield et al. 2000a). Currently, these visitors park at various

locations in West Yellowstone and use the oversnow vehicles to gain access to Madison,

Old Faithful, and other areas of YNP.

Plowing the roadway segment between West Yellowstone and Old Faithful would close

access to the park for oversnow motorized winter use recreational visitors from the West

Entrance. Limited private vehicle access, including private snowmobile trailers, would

be permitted within YNP. A shuttle system would provide access between West

Yellowstone and Old Faithful for visitors destined for Madison or Old Faithful.

While not expressly defined in this alternative, limited access to Old Faithful would be

provided for private vehicles. Under one potential scenario for private vehicle access,

about 10 to 20 trailer spaces would be available at Old Faithful for snowmobile trailer

parking with up to 40 spaces for passenger vehicles. These spaces would be managed

through a reservation system. In addition to the private vehicle spaces, this scenario

would provide up to 30 additional spaces for tour bus and shuttle vehicle staging. Visitor

equivalents for private passenger vehicles and snowmobile trailers under this scenario are

116 passenger vehicle visitors (40 vehicles x 2.9 persons per vehicle) and up to 140

snowmobile passengers (20 trailer spaces x 7 (average) machines per trailer x 1

passenger per machine).

While access for oversnow motorized vehicles would be limited through this alternative,

access for visitors could be increased to Madison and Old Faithful. The proposed shuttle

system could potentially operate using 15-passenger vans with five-minute minimum

headways (12 trips per hour). Given visitor arrival and departure rates, a shuttle system

operating with 15-passenger vehicles and a peak headway of five-minutes, a maximum of

900 daily visitors can be accommodated between West Yellowstone and Old Faithful.

Assuming an average of 20 buses operating daily (where there is capacity for 30 parked

buses), an additional 800 visitors could be transported to Old Faithful (20 buses x 40

occupants per bus). Present access to YNP through the West Entrance is about 840 daily

visitors per average February weekend. The number of winter visitors to Old Faithful

that could be accommodated, including shuttle, bus, and private parking is about 1,920

through the actions of this alternative.

The current peak use is reflected by an actual count of 1,251 snowmobiles through the

West Entrance (about 1,500 people). Peak use could be accommodated in this
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

294

alternative. The previous discussion involves existing capacity at Old Faithful. It is not a

prediction of increased use at Old Faithful. It indicates that under this alternative the

available physical parking capacity could accommodate current use levels. The existing

physical capacity for snowmobiles far exceeds that for automobiles.

In GTNP and the Parkway alternative B alters the internal park circulation patterns for

motorized oversnow vehicles on Teton Park Road as they currently operate. Access

between Jackson Lake Junction and Jenny Lake for oversnow motorized vehicles is

closed. However, other similar snowmobile opportunities are available in the park and

total visitor access would not be expected to change.

The closure of YNP’s West Entrance to oversnow access could enhance the importance

of access for snowmobiles through GTNP and the Parkway to YNP. Winter scenery and

wildlife in YNP will continue to attract potential visitors. Access for the numbers of

snowmobile and snowcoach visitors currently using the West Entrance could shift to the

South Entrance. The staging for oversnow opportunities from these routes could increase

use at Flagg Ranch. Parking capacity would not increase at Flagg Ranch, providing an

upper limit in the amount of use that may shift to this area. In addition the long travel

distance from Jackson to Flagg Ranch and Flagg Ranch to destinations in YNP will

remain a deterrent.

A reasonably foreseeable distribution of vehicle use as a consequence of this alternative

is depicted in the following table. It shows a loss of 554 snowmobile trips from West

Yellowstone to Madison and 489 from Madison to Old Faithful. Park wide snowcoach

vehicle-miles would decrease by 40%. There would be a net decrease of 25% in

snowmobile vehicle-miles traveled in the three park units and a net increase of 21%

wheeled-vehicle-miles traveled on the same road segments.
IMPACTS OF IMPLEMENTING ALTERNATIVE B

295

Table 86. Alternative B motorized use.

Average Daily Vehicle Use January-February

Road Segment Autos Vans Snowcoaches Snowmobiles Buses

Mammoth to Northeast Entrance No change from current condition

Mammoth to Norris 0 0 3 56 0

West Entrance to Madison 50 80 0 0 2

Madison to Norris 0 0 5 42 0

Norris to Canyon Village 0 0 4 56 0

Canyon Village to Fishing Bridge 0 0 3 242 0

Fishing Bridge to East Entrance 0 0 0 67 0

Fishing Bridge to West Thumb 0 0 3 248 0

Madison to Old Faithful 50 81 0 0 2

Old Faithful to West Thumb 0 0 4 338 0

West Thumb to Flagg Ranch 0 0 4 322 0

Grassy Lake Road No change from current condition

Flagg Ranch to Colter Bay 100 10 0 25 1

Colter Bay to Moran Junction No change from current condition

Moran Junction to East Entrance No change from current condition

Moran Junction to South Entrance No change from current condition

Teton Park Road 0 0 0 0 0

Moose-Wilson Road 5 0 0 3 0

Antelope Flats Snowmobile Route No change from current condition

Concession Services

Present concessions affected in this alternative would be those permitted to run oversnow

guided services from West Yellowstone, into Mammoth and Gardiner into YNP, and

those located at Old Faithful. This includes snowmobile and snowcoach tours.

Oversnow guided tours to Old Faithful from West Yellowstone, Mammoth, and Gardiner

could no longer operate in that fashion because of the change to wheeled, mass transit

access (West Yellowstone to Madison, and Madison to Old Faithful). This represents the

greatest adverse impact on concessions, relative to lost business and the need to

completely change business focus regarding access.

Staging at Norris and Madison would be limited. The logistics of moving employees,

clients, or supplies from Mammoth to Old Faithful involve travel both oversnow and via

plowed road. According to the concessioner, this could make the lodging operation at

Mammoth less desirable from both an operating efficiency standpoint and because it

would be less enjoyable to visitors traveling between Mammoth and Old Faithful

(Comment on the DEIS, YNP Lodge Co.). The result could be a less viable operation at

Mammoth. Guided snowmobile and snowcoach tours from Mammoth and Gardiner
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

296

would be less attractive, because the trip to Old Faithful becomes longer, and is not as

logistically feasible for day trips. This could result in lost business at Mammoth, and

higher costs that would adversely affect the service provider.

From the perspective of the operation at Old Faithful, the logistics of moving people,

fuel, supplies, or garbage would no longer be limited by oversnow means. Material

storage in the park’s interior would be less of a problem. For both Old Faithful, to a

degree, and West Yellowstone, a different national park clientele could be expected. The

mode of access changes between the two, but the business of moving people from one to

the other remains. Therefore, opportunities would exist for new or adapting

concessions/businesses based in West Yellowstone. Businesses would have two years to

adapt, until road plowing would be implemented in winter 2002-2003.

Yellowstone National Park Lodge Company suggests plowing the entire north and west

side of the park, thereby easing logistics and making the northern route to Old Faithful as

attractive by wheeled-vehicle as the route from the west. The NPS determined that

plowing the road from Mammoth to Norris and then south to Madison is not feasible for

several reasons. These sections of road receive more snow and wind during the winter

season than other road sections proposed for plowing. Park maintenance staff is

concerned that during the deep winter, the narrow curvy road template, coupled with high

crosswinds would prohibit any degree of certainty in keeping the road open. Plowing

during the late winter season, as considered in alternative C, is the most feasible option

for plowing these segments.

Implementing any alternative that might substantially affect a concessioner would require

negotiation between the NPS and the concessioner, or be deferred until a new

concessions contract is awarded.

Concessions or services operating at other locations in the parks or from other gateways

would not be affected greatly. Current circumstances are attractive to snowmobilers who

enter at the East and South Entrances to YNP. These circumstances would change in this

alternative. Snowmobilers would no longer be able to travel from the other entrances to

West Yellowstone (or the reverse) to stay overnight. Also snowmobilers would no

longer be able to run the “Grand Loop.” These circumstances affect a small percentage

of use in the parks, most often on holiday weekends, and would have less effect on

guides who facilitate this use. Most guided tour concessions engage in day use but offer

some specialized Grand Loop trips with an evening stay in West Yellowstone.

Conclusion

Due to the net lack of change in access to YNP through the West Entrance, this

alternative would result in negligible, short-term impacts on visitor access. In the future

there could be adverse effects if the demand for available access to Old Faithful exceeds

the capacity for parking at that location. Although oversnow use would be eliminated

between West Yellowstone and Old Faithful, the introduction of alternative modes of
IMPACTS OF IMPLEMENTING ALTERNATIVE B

297

transportation would surpass the level of access currently realized through existing

transportation modes. Access would not be impacted at other locations in YNP. Shortterm impacts to visitor access in GTNP and the Parkway would be minor.

Effects on Visitor Experience — Yellowstone National Park

The amount and type of winter visitor opportunities offered in YNP under alternative B

are provided in Table 87.

Table 87. YNP Visitor opportunities available under alternative B.

Opportunities Miles or

Areas

Increase/

Decrease

Length of

Season Other

Groomed motorized route 154 -30 Mid-December

to Mid-March

Late night closure

11 P.M. to 5 A.M.

Groomed motorized route,

snowcoach only

0 0 Mid-December

to Mid-March

Late night closure

11 P.M. to 5 A.M.

Groomed motorized trail 6 +6 Mid-December

to Mid-March

Late night closure 11

P.M. to 5 A.M.

Plowed route 106 +30 Mid-December

to Mid-March

Late night closure

11 P.M. to 5 A.M.

Groomed nonmotorized 47 +10 Mid-December

to Mid-March

Late night closure

11 P.M. to 5 A.M.

Warming huts 9+/- 3 Mid-December

to Mid-March

Late night closure

11 P.M. to 5 A.M.

Backcountry 2.2 million

acres

Some

restrictions in

about.

700,000 acres

Contingent on

snowfall in

northern portion

of park

None

Visitor Satisfaction and Experience

Opportunities to View Wildlife. Under alternative B visitor access from the West

Entrance to Madison and south to Old Faithful is provided via a mass transit shuttle bus.

Because visitors riding on the shuttle would be traveling in groups, wildlife viewing

would rarely be a solitary or individualized experience. If wildlife habituates to the new

travel patterns of the shuttle, wildlife viewing on this road section could be improved.

Wildlife viewing opportunities on other road segments would be the same as under

alternative A, no action.

Opportunities to View Scenery. Some views along the road segment from West

Entrance to Old Faithful would be obstructed by snow. These types of impacts occur

intermittently and generally on one side of the road for about 4 miles from the West

Entrance to Madison Junction. From Madison Junction south to Old Faithful this type of

terrain occurs intermittently for about 4 miles. Snow berms in this type of terrain could

exceed 12 feet and would obstruct views. In areas where the terrain is open and flat,

snow berms would be generally less than 6 feet (assuming snowfall accumulation of 95

inches). Snow blowing and removal could mitigate these impacts in some areas.

However, visitors would experience short-term moderate adverse impacts on their
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ENVIRONMENTAL CONSEQUENCES

298

opportunities to view scenery along these road segments. These impacts would vary with

the time of year, the type of vehicle used, and the amount of snowfall. Views along other

park roads would not be impacted.

Because of the required use of mass transportation from West Yellowstone to Old

Faithful visitors would not experience the personal freedom to stop and view scenery at

will.35

Safety. The separation of some snowmobile and ski trails would have a minor beneficial

effect on all users. An aggressive information program would provide visitors with more

access to safety information as well as trail conditions and weather alerts.

Quality of the Groomed Surface. Late night closures would improve the condition of

the groomed surface by allowing the groomed surface to hardened overnight. Under this

alternative the poorest of the snow road sections from West Entrance to Old Faithful

would be plowed. If eliminating oversnow travel displaces use to the park’s eastern side,

the quality of the snow surface there would decline.

The Availability of Access to Winter Activities or Experiences. This alternative

eliminates snowmobile and snowcoach travel from the West Entrance to Old Faithful. In

addition the road plowing option eliminates the opportunity for snowmobile and

snowcoach riders to experience the entire Grand Loop oversnow. About 10% of winter

day visitors indicated that they traveled the entire Grand Loop (Littlejohn 1996). For

visitors wishing to visit more than Old Faithful in one day, this alternative will likely

require some advance planning to access the YNP by different transportation modes. A

limited number of private vehicles and buses would be allowed to access Old Faithful by

reservation only. For these reasons alternative B would eliminate or detract from several

critical characteristics of the desired winter experience for a large number of participants

(about 48% of all winter users in 1998-99).36

Visitors who are unable, cannot afford, or do not wish to ride a snowmobile or

snowcoach would have access via a shuttle vehicle to Old Faithful. Because the winter

experience at Old Faithful has not been available to these users, alternative B would

increase opportunities for this type of experience. However, the number of potential

visitors who would utilize this form of access is unknown. Due to lack of public support

for this alternative, the beneficial effects from this increase in opportunities are expected

to be negligible.

 

35 Impromptu stops by snowcoaches to view scenery and wildlife are frequent occurrences under current

operations and there is no reason to assume that this situation would change.

36 In recent surveys, plowing the road as a management option received support from only 4.2% of

respondents (Duffield et al. 2000a, 2000b, 2000c). Results from the winter visitors survey indicated that

under this alternative, YNP would experience an 18.4 % decrease in visitation. Similarly, of the public

comments on the DEIS that voiced support for a particular management action, plowing the road received the

least support (less than 1%).
IMPACTS OF IMPLEMENTING ALTERNATIVE B

299

This alternative would not affect oversnow access via the East, South, and North

Entrances. However, the addition of another mode of transportation would add a degree

of difficulty to trip planning for all winter visitors to YNP. These visitors, particularly

those entering from the north, may choose to avoid the problems of transferring from

oversnow travel to transit busses at Madison Junction and enter the park via the West

Entrance.

The addition of groomed motorized trails would create a less maintained experience for

motorized users, which has not previously been available to park visitors.

Availability of Information. Additional visitor contact stations, warming huts and an

aggressive information program would enhance visitor safety and understanding of the

winter environment.

Quiet and Solitude. Park visitors riding the shuttle bus on busy weekend days would

find little opportunity for solitude on the road from West Yellowstone to Old Faithful.

Because of the requirement for mass transit, visitors may experience more crowding at

attractions such as Old Faithful, Black Sand Geyser Basin, and at the warming hut at

Madison Junction. Snowmobilers that currently use the West Entrance may be displaced

to other areas of the parks. This displaced use would adversely affect the ability of the

snowmobile visitor to find solitude in the parks, and may increase use at attraction sites

such as West Thumb and the Grand Canyon of the Yellowstone. The implementation of

use limits in some areas of the park would mitigate these effects.

Because use in important or sensitive resource areas is restricted to designated trails,

backcountry skiers may find reduced opportunities for solitude under alternative B.

Under this alternative, all oversnow vehicles would be required to meet strict sound

standards. These standards would be implemented at various levels over the next 10

years. While the short-term changes in the soundscape would be minor, the long-term

goal of reducing snowmobile sound emissions would greatly enhance the ability to

experience quiet in YNP. The use of mass transit shuttle buses would also increase

opportunities to experience quiet, particularly near the West Entrance to Old Faithful

travel corridor.

Clean Air. Under alternative B, all oversnow vehicles would be required to meet strict

emissions standards. These standards would be implemented at various levels over the

next 10 years. While the short-term (less than 5 years) changes in visitor experience

would be minor, the long-term goal of reducing snowmobile emissions and the use of

mass transit shuttle buses would greatly enhance the ability to experience clean air in

YNP. These effects would be particularly beneficial at the West Entrance and Old

Faithful.
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300

Conclusion

Alternative B would eliminate or detract from several critical characteristics of the

desired winter experience. These adverse impacts would affect winter visitors that access

YNP via the West Entrance on snowmobiles and in snowcoaches (about 48% of all

winter visitors). This action would result in major to moderate adverse impacts to the

desired winter experience of these visitors.

Plowing the road from the West Entrance to Old Faithful would create berms of snow

that would limit opportunities to view scenery in some areas. Logistically, travel in YNP

would become more complex, particularly for travelers entering the park from the north.

This action would have a direct minor to moderate adverse impact on the desired winter

experiences of visitors traveling these corridors.

The winter experience at Old Faithful has not been available to park visitors who do not

wish or who cannot afford to ride a snowmobile or snowcoach. Because alternative B

would provide a previously unavailable winter experience, it would have benefits for

park visitors in this group. However the magnitude of effect of this action is expected to

be negligible.

The reduction of snowmobile emissions and sound levels would, over time, provide

increased opportunities for clean air, and natural quiet. The result of these actions would

result in moderate to major beneficial improvements to the desired visitor experience.

Under specific circumstances, the adaptive management provisions of this alternative

may result in area closures. If monitoring or scientific studies regarding winter visitor

use, natural resources, and other park values indicate that sections of the park must be

closed or certain uses restricted to protect park values (for example, snowmobiling or

backcountry skiing), some or all visitor experiences in the closure area would be

eliminated (see Chapter II, Adaptive Management). These areas of closure would result

in direct localized adverse impacts on the desired winter visitor experience. However,

the long-term protection of these resources would provide major benefits to the desired

visitor experiences park-wide.

Effects on Visitor Experience — Grand Teton National Park and the

Parkway

The amount and type of winter visitor opportunities offered in GTNP under alternative B

are provided in Table 88.
IMPACTS OF IMPLEMENTING ALTERNATIVE B

301

Table 88. GTNP Visitor opportunities available under alternative B.

Opportunities

Miles or

Areas

Increase/

Decrease Length of Season Other

Groomed motorized route 2.1 0 December to April† Late night closure

Groomed motorized route,

snowcoach

2.1 0 December to April† Late night closure

Groomed motorized trail 34.0 0 December to April† Late night closure

Plowed road 100.0 0 December to April† Late night closure

Ungroomed motorized trail

or area

11.3 -24.3 December to April† Late night closure

Groomed nonmotorized 0 0 December to April† Late night closure

Ungroomed nonmotorized

trail or area

32.9 6.5 December to April† Late night closure

Warming huts/Interpretive

centers

6.0 4.0 December to April† Late night closure

† Variable, dependent on snow conditions

Visitor Satisfaction and Experience

Opportunities to view wildlife and scenery. Visitors on plowed roads, the CDST, and

Jackson Lake would continue to enjoy wildlife and scenery viewing. Fewer viewing

opportunities would be available for snowmachine users along the Teton Park Road and

on Jackson Lake. Viewing opportunities for nonmotorized users in these areas would be

similar to the no action alternative.

Safety (the safe behavior of others). Eliminating oversnow vehicles from the Teton

Park Road would result in greater separation of motorized and nonmotorized users

compared to alternative A. Separation of the CDST from the highway on a newly

constructed, year-round pathway would enhance safety.

Quality of the groomed surface. There would be no fewer groomed surfaces in this

alternative than in alternative A. Grooming more frequently would enhance the surface

of the Grassy Lake Trail. Relocating the CDST to a separate path from Colter Bay to

Flagg Ranch would improve the snow quality of the groomed surface while separating

auto traffic from snowmachines.

The availability of access to winter activities or experiences. The forms of access

would remain the same as in alternative A, but fewer miles of ungroomed motorized

trails would be available. Ice fishing opportunities via snowmobile would be lost on

Jackson Lake over time. Currently this represents a quarter of the angling that occurs

year-round. Because snowmobiles would no longer be permitted on Jackson Lake, some

backcountry skiers would find travel more difficult, particularly to Webb Canyon.
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302

Availability of information. Increased and enhanced visitor programs, facilities, and

interpretive opportunities would better meet the expectation and need for information.

Quiet and solitude. Reducing motorized sound levels over time and separating uses on

the Teton Park Road would enhance quiet use opportunities, particularly for

nonmotorized visitors. Opportunities for solitude would be greatly increased for

nonmotorized uses. The sound of snowplanes would continue to impact backcountry

users in GTNP in some areas west of Jackson Lake.

Areas of the park that have previously not experienced high levels of snowmobile use

may experience an increase. Snowmobile users that currently enter the parks from the

West Entrance of YNP may be displaced to other areas of the parks if mitigating interim

use limits are not implemented. This displaced use would adversely affect the ability of

the snowmobile visitor to find solitude and quiet in the parks, and could increase levels of

use particularly from the South Entrance.

Clean air. Over time reduction of allowable emission levels, combined with separation

of uses on the Teton Park Road would help meet expectations for clean air, particularly

for nonmotorized users.

Conclusion

Changes in opportunities for visitor experience relating to wildlife and scenery viewing

would be negligible. Separating user groups within the park and improving groomed

surfaces would result in moderate benefits to safety. Access to winter activities would

decrease moderately due to the net loss of areas available for snowmobile use. There

would be a major beneficial improvement to visitor experience due to greatly increased

availability of information, interpretation, and winter programs. Generally, there would

be a moderate beneficial impact to opportunities for quiet and solitude. Opportunities to

appreciate clean air would be moderately to greatly improved, particularly in the Flagg

Ranch area.

IMPACTS OF IMPLEMENTING ALTERNATIVE C

Effects on the Socioeconomic Environment

Alternative C contains several provisions for relatively minor changes in trails

management and grooming within YNP and GTNP. Most of these changes would not

substantially affect visitor decisions on whether to visit the parks for recreation. Like

alternative B, the proposal to plow the road from West Yellowstone to Madison Junction

to Old Faithful has the potential to significantly impact GYA visitation levels and,

therefore, visitor expenditures and the overall level of economic activity within the GYA.

Regional Economy. The impacts of alternative C with regard to plowing the West

Yellowstone to Old Faithful road are the same as for alternative B. The effects of

alternative C on visitation and visitor expenditures in GTNP and the Parkway are

expected to be the same as alternative B.
IMPACTS OF IMPLEMENTING ALTERNATIVE C

303

In addition to the plowing of the West Yellowstone to Old Faithful road segment,

alternative C proposes plowing the road from mid-February to mid-March from

Mammoth to Norris to Madison for auto and bus use. Alternative C proposes to allow

only snowcoach, ski, and snowshoe travel in the eastern portion of the park (Norris to

Canyon to Fishing Bridge roads) from mid-February to mid-March. It is unknown if the

combination of decreased snowmobiling opportunities and increased auto and ski

opportunities would effect overall winter visitor numbers.

Three-State Regional Economy. The impacts of alternative C on the three-state

regional economy with regard to plowing the West Yellowstone to Old Faithful road are

the same as for alternative B.

Minority and Low-Income Populations. It is anticipated that the impacts on minority

and low-income populations from the proposed alternative C actions would be the same

as those found under alternative B.

Social Values. It is anticipated that the impacts on social values from the proposed

alternative C actions would be the same as those found under alternative B.

Nonmarket Values. It is anticipated that the impacts on nonmarket values from the

proposed alternative C actions would be similar to those found under alternative B. The

exception is that under alternative C, there would be no benefits to snowmobile users

from a requirement to use clean and quiet technology in the future.

Conclusion

Like alternative B, alternative C road plowing actions would have a negligible to minor

impact on the five-county and three-state economies through reduced visitation and

nonresident visitor expenditures. These expenditure reductions may be a moderate

negative impact on small communities adjacent to YNP, primarily West Yellowstone.

The alternative C road plowing actions would also have a moderate negative impact on

total current trip nonmarket visitor benefits (through reduced visitation) and a minor

positive impact on nonmarket benefits through improved winter access to Old Faithful.

Low-income visitors could realize a minor to moderate benefit from the alternative C

actions, which would make access to the YNP more affordable.

Effects on Air Quality and Public Health

Like Alternative B, under Alternative C snowmobiles would no longer enter YNP at the

West Entrance and travel to Old Faithful. These snowmobiles and snowcoaches would

be displaced by wheeled-vehicles that would operate on a plowed road from the West

Entrance to Old Faithful. Alternative C would have fewer mass transit vans operating to

Old Faithful from the West Entrance than alternative B, and only bio-based lubricants

and 10% ethanol fuel blends would be sold in the park for all vehicles. Table 89, Table

90, and Table 91 summarize the results of CO modeling for six locations in the three

parks for alternative C. Table 89 and Table 90 show the predicted maximum 1-hour
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ENVIRONMENTAL CONSEQUENCES

304

average CO concentrations and the calculated maximum 8-hour average CO

concentrations, respectively. Table 91 also provides the percent contribution of each

vehicle type, including snowplows, to the maximum CO concentrations for the six

locations. Table 92 and Table 93 provide corresponding model results for PM10 for the

same locations and conditions as those for CO.

Visibility

The visibility assessment indicates that under this alternative, vehicular emissions would

not cause any perceptible visibility impairment near the West Entrance or along the

roadways. Perceptible visibility degradation could occur near Old Faithful and Flagg

Ranch when vehicles idle for extended periods.

Conclusion

As noted in Table 89, Table 92, and Table 93, the model predicts major beneficial

impacts relative to alternative A at the West Entrance and along the West Entrance to

Madison roadway. Like alternative B, both CO and PM10 concentrations would be

reduced by more than 85%. Moderate CO reductions are predicted for alternative C at

the Old Faithful staging area, and a minor beneficial impact on CO concentrations is

predicted at the Flagg Ranch staging area and along the Flagg Ranch to Colter Bay

roadway. For PM10 a major beneficial impact would be realized at the Old Faithful and

Flagg Ranch staging areas, and a moderate beneficial impact is predicted along the Flagg

Ranch to Colter Bay roadway.

Table 89. Maximum 1-hour average CO concentrations for alternative C.

Location

1-hr

Maximum

Concentration

(w/o

Background)

(ppm)

1-hr Maximum

Concentration

(w/Background)

(ppm)

Change Relative

to alternative A

(w/o

Background)

(%)

West Yellowstone Entrance 0.60 3.60 97.9

West Entrance to Madison Roadway 0.30 3.30 97.5

Old Faithful Staging Area 0.99 3.99 22.8

Flagg Ranch Staging Area 1.39 4.39 19.0

Flagg Ranch to Colter Bay Roadway 1.00 4.00 9.1

Mammoth to NE Entrance Roadway 0.30 3.30 0
IMPACTS OF IMPLEMENTING ALTERNATIVE C

305

Table 90. Maximum 8-hour average CO concentrations for alternative C.

Location

8-hr Maximum

Concentration

(w/o Background)

(ppm)

8-hr Maximum

Concentration

(w/Background)

(ppm)

Change Relative

to alternative A

(w/o Background)

(%)

West Yellowstone Entrance 0.28†

1.69†97.9

West Entrance to Madison Roadway 0.14†1.55†97.5

Old Faithful Staging Area 0.17 1.57 22.8

Flagg Ranch Staging Area 0.23 1.64 19.0

Flagg Ranch to Colter Bay Roadway 0.47†1.88†9.1

Mammoth to NE Entrance Roadway 0.14†1.55†0

†Estimated from the modeled maximum 1-hour average concentration based on the persistence formula

 Ct2 = Ct1*(t1/t2)^0.365 (Cooper and Alley 1990).

Table 91. Vehicle contribution to CO concentrations for alternative C.

Contribution (%)

Location SM SC AM LT HT TB SV

West Yellowstone Entrance 0 0 27.5 54.0 2.3 1.5 14.7

West Entrance to Madison Roadway 0 0 23.1 58.4 1.6 1.0 15.9

Old Faithful Staging Area 77.9 0.9 6.0 12.0 0.1 0.1 3.0

Flagg Ranch Staging Area 78.9 0.8 6.1 12.0 0.1 0 2.0

Flagg Ranch to Colter Bay Roadway 49.8 0 13.3 31.1 0.3 0.2 5.3

Mammoth to NE Entrance Roadway 0 0 26.5 66.8 0.6 0 6.1

SM = snowmobile, SC = snowcoach, AM = automobile, LT = light truck, HT = heavy truck, TB = tour bus, SV = shuttle

van.

Table 92. Maximum 24-hour average PM10 concentrations for alternative C.

Location

24-hr Maximum

Concentration

(w/o background)

(μg/m3)

24-hr Maximum

Concentration

(w/background)

(μg/m3)

Change Relative

to alternative A

(w/o background)

(%)

West Yellowstone Entrance 0.32†23.32 99.3

West Entrance to Madison Roadway 0.32†23.32 97.1

Old Faithful Staging Area 0.18 5.18 71.5

Flagg Ranch Staging Area 0.26 5.26 59.5

Flagg Ranch to Colter Bay Roadway 0.63†5.63 33.3

Mammoth to NE Entrance Roadway 0.32†5.32 0

†Estimated from the modeled maximum 1-hour average concentration based on the persistence formula

 Ct2 = Ct1*(t1/t2)^0.365 (Cooper and Alley 1990).

Table 93. Vehicle contribution to PM10 concentrations for alternative C.

Location

Contribution (%)
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

306

SM SC AM LT HT TB SV

West Yellowstone Entrance 0 0 4.5 9.2 51.9 31.8 2.5

West Entrance to Madison Roadway 0 0 8.9 18.7 43.2 24.1 5.1

Old Faithful Staging Area 98.0 0 0 0 1.0 1.0 0

Flagg Ranch Staging Area 98.8 0 0 0 0.7 0.4 0

Flagg Ranch to Colter Bay Roadway 39.8 0 9.9 19.4 19.6 7.9 3.3

Mammoth to NE Entrance Roadway 0 0 20.3 42.8 33.0 0 3.9

SM = snowmobile, SC = snowcoach, AM = automobile, LT = light truck, HT = heavy truck, TB = tour bus, SV = shuttle

van.

Effects on Public Safety

The safety-related effects of plowing the road from West Yellowstone to Old Faithful

would be similar to those of alternative B. However, potential for visitor conflicts on this

road would increase due to the absence of shuttle buses and reservation limitations on

private wheeled-vehicles. Unregulated private wheeled-vehicle access to both road

segments would have moderate adverse impacts on the safety of park visitors. Some

visitors entering the YNP in private vehicles would be ill-prepared for the harsh

environment and dangerous winter road conditions. This would result in increased motor

vehicle accidents, vehicle-wildlife collisions, and risk of injury due to exposure to

extreme winter conditions. The late season plowing of the roadway segments from

Madison to Mammoth would have the same effects as plowing the road from West

Yellowstone to Old Faithful. Restricting use on the road from Norris to Canyon to

snowcoaches only would reduce the potential for visitor conflicts during one month of

the season.

In GTNP this alternative would slightly decrease the potential for inter-modal conflict by

widening the highway shoulder between Moran and Flagg Ranch. It would increase the

potential for user conflict by developing or maintaining ungroomed trails for use by both

motorized and nonmotorized uses in close proximity along the Teton Park Road and

Signal Mountain Road.

Conclusion

Implementing this alternative would result in moderate adverse impacts to public safety

in YNP. This is primarily due to the potential for increasing visitor conflicts and vehicleanimal collisions that would result from plowing several road segments (in the absence of

offsetting beneficial effects or mitigation). The safety effects of a greater separation of

uses would be negligible. Impacts to public safety are expected to be minor and adverse

due to the introduction of potential user conflicts.

In GTNP the widened highway shoulder for the CDST would only negligibly improve

safety, because it would not extensively alter the actions currently in place to separate

snowmobile and wheeled-vehicle use along the trail.
IMPACTS OF IMPLEMENTING ALTERNATIVE C

307

Effects on Geothermal Features

Under alternative C the park roads would be groomed near the geothermal features

described in alternative B. The impacts on those features described in alternative B

would be similar under this alternative.

Plowing the road from West Yellowstone to Madison and Madison to Old Faithful would

have similar impacts on geothermal features as those described in alternative B. There

could be increased adverse impacts on geothermal features given no fall closure along the

plowed road, and visitors would be able to access the features along the road throughout

the fall and early winter.

Access to Old Faithful by both snowmobiles and wheeled-vehicles would have similar

impacts on Old Faithful features as described under alternative B.

The number of nonmotorized groomed trails in geothermal areas would increase. The

geothermal areas included in this activity are Mammoth Terraces, Lone Star Geyser

Basin, Norris Geyser Basin, the lower geyser basin, and Fountain Flats. New groomed

trails would increase access and in turn increase potential adverse impacts on geothermal

areas. Overall, the proposed new groomed nonmotorized trails would result in a minor

increase in impacts on geothermal basins.

The construction of a Norris warming hut would have the same impacts on geothermal

features as those described under alternative A. Winter campsites would be provided at

Old Faithful, which could increase the amount of visitor use overnight and of the

geothermal basin. More visitors in the area would cause minor increases in adverse

impacts on the geothermal features. Unregulated backcountry use would have the same

impacts on geothermal features as described under the no action alternative. Increased

interpretation opportunities would have the same beneficial impacts on geothermal

features as described under alternative B.

Conclusion

Actions in alternative C could result in an overall increase in human access to geothermal

areas at Old Faithful, Norris, West Thumb, and in areas located along the roads from

Madison to Old Faithful. These actions include plowed roads, longer fall and spring

seasons, warming huts, winter camping, spring plowing, groomed motorized and

nonmotorized trails, and nonrestricted backcountry use. As a result there would be minor

incremental long-term degradations to thermal features, and in some cases permanent

loss of certain features. By increasing interpretative opportunities, some of the effects of

increased use could be mitigated.

Water and Aquatic Resources

Potential pollution sources are the same as described in alternative A. The potential

impacts on water quality would be the same as described in alternative B with the

following exceptions.
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ENVIRONMENTAL CONSEQUENCES

308

There would be no change in risk along the Teton Park Road (“low” risk) segment from

that described in alternative A. There would be no change in the input of pollutants on

the surface of Jackson Lake, hence no reduction in the risk of degradation in that water

body.

The risk of water quality pollution would be decreased along the “low” risk MooseWilson Road segment with the prohibition of snowmobiles. The risk of water quality

pollution would be increased along the “low” risk Antelope Flats Snowmobile Route

with the increase of snowmobiles on that segment.

Table 94.37 Snowmachines and associated risk levels for alternative C.

Impact: Daily Vehicle

Miles Traveled Along

the Segment in Alt. A*

Impact: Daily Vehicle

Miles Traveled Along

the Segment in Alt. C*

Road Segment Risk Rating† SM SC SM SC

Mammoth to Norris Medium 641 69 1176 63

West Entrance to Madison Medium 7759 127 0 0

Madison to Norris High 3458 73 588 56

Norris to Canyon Village Low 2214 47 672 48

Canyon Village to Fishing Bridge High 2370 50 3872 48

Fishing Bridge to East Entrance Medium 983 0 1809 0

Fishing Bridge to West Thumb Medium 2627 55 5208 63

Madison to Old Faithful High 7818 165 0 0

Old Faithful to West Thumb Medium 3560 73 5746 68

West Thumb to Flagg Ranch Medium 4219 103 7728 96

Grassy Lake Road High 184 0 400 0

Flagg Ranch to Colter Bay Low 379 0 800 0

Colter Bay to Moran Junction High 248 0 250 0

Moran Junction to East Entrance Medium 49 0 50 0

Teton Park Road Low 156 0 0 0

Moose-Wilson Road Low 6 0 6 0

Antelope Flats Snowmobile Route Low 0 0 0 0

Conclusion

Deposition into snowpack would continue to occur from 2-stroke engine emissions along

groomed park roads in YNP and GTNP. The effect of this deposition on water quality is

undetermined, but there is currently no evidence of measurable changes in water quality

or effects on aquatic resources. It is possible that accumulations of pollutants in aquatic

systems may have adverse impacts on wetlands and aquatic resources downstream from

 

37 SM = Snowmobile, SC = Snowcoach; the source of pollutants is emissions from snowmobiles, which

produce (conservatively) ten times as many emissions per mile as most wheeled vehicles. Single

snowcoaches produce fewer emissions then single snowmobiles.

†High = within 100 meters of aquatic system on 76% to 100% of the road segment; Medium = within 100

meters on 51% to 75% of the road segment; Low within 100 meters of rivers less than 50%.
IMPACTS OF IMPLEMENTING ALTERNATIVE C

309

high risk road segments. Oversnow vehicle use in this alternative involves localized high

risk to surface water quality, but reduces oversnow vehicle-miles traveled along high risk

road segments in the three park units by about 62%. Snowmobile and snowplane use on

Jackson Lake would continue the risk of moderate to major adverse impacts on water

quality in that water body. Minor to moderate long-term adverse impacts on water

resources throughout GTNP and the Parkway could occur because of the increased

number of winter use opportunities. Minor short-term water quality and wetland impacts

could occur in streams along the eastern side of US 89/287 as a result of CDST

construction.

Mitigation

The portions of the CDST that would deviate from the road shoulder would be designed

and sited to minimize impacts on all park resources including wildlife, vegetation, and

wetlands. Focused water monitoring programs should be designed and implemented to

determine whether there are specific aquatic resource effects from winter recreational

use. The use of bio-based fuels by NPS and the availability of fuels in gateway

communities may result in a minor decrease in pollutant deposition into snow. Best

management practices would be used during the construction, reconstruction, or winter

plowing of trails and roads to prevent unnecessary vegetation removal, erosion, and

sedimentation. The release of snowpack contaminants into surface water could be

mitigated by disconnecting snowmelt drainages from motorized trails. Any new or

reconstructed winter use sanitary facilities would be constructed in locations and use

advanced technologies that would protect water resources. A focused program of

monitoring would reduce the uncertainty of impacts from oversnow vehicles, and if

necessary, indicate best management practices that might be implemented.

Effects on Wildlife

Ungulates

Effects of groomed roads and trails. Packed trails may influence wildlife movements

and distributions by facilitating travel into areas that would normally be inaccessible due

to deep snow. Under alternative C GTNP and the Parkway would groom about 66 miles

for motorized use, an increase of about 30 miles over current management, and 4 miles

for nonmotorized use. The new groomed motorized route will begin near the south

boundary, follow the Gros Ventre River, and then parallel the eastern boundary up to

Moran. YNP would groom 164 miles for motorized use, a decrease of 20 miles, and 47

miles for nonmotorized use. This represents an increase of 10 miles over current

management.

In GTNP effects related to packed trails would be greater than those under alternative A.

The elimination of a packed road surface from West Entrance to Old Faithful would

decrease impacts associated with groomed roads relative to alternative A.
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ENVIRONMENTAL CONSEQUENCES

310

Effects of motorized oversnow use of groomed and ungroomed roads and trails. The

use of motorized oversnow vehicles can cause injury and death to wildlife, especially in

poor lighting conditions and during snowfall, and can cause displacement from preferred

habitats.

The addition of 30 miles of oversnow motorized trail in GTNP could result in moderate

to major impacts on wildlife. The new trail along the Gros Ventre River would displace

ungulates, primarily moose and elk, from the river corridor and inhibit movements within

and among winter ranges in the southern part of the park. The periodic departure of the

CDST from the highway shoulder to scenic diversions could also impact ungulates,

especially moose on the segment from Moran to Jackson Lake. In YNP the associated

effects of oversnow motorized vehicles would be reduced due to the plowing of the route

from West Yellowstone to Old Faithful.

Effects of plowed roads. Road plowing may cause habitat fragmentation by creating

structural barriers (i.e., snow berms) to ungulate movements (Aune 1981). In addition

plowed roads, like groomed roads, also may provide an energy efficient mechanism for

wildlife movements, including bison, elk, and moose. Under alternative C the effects

described above are associated with about 106 miles of road in YNP, an increase of 30

miles over existing management to accommodate private wheeled-vehicles from West

Entrance to Old Faithful. The miles of plowed roads in GTNP and the Parkway would

increase marginally from about 100 miles to 104 miles to allow for wheeled-vehicle

access on the Moose-Wilson Road.

In YNP the plowed road from West Entrance to Old Faithful would result in more snow

berms, thus potentially increasing fragmentation along this segment. An increase in

ungulate use of the plowed road as compared to the currently groomed road is not

expected because plowed roads do not offer additional energy savings over groomed

roads. The effects of plowed roads in GTNP would be essentially the same as those

described in alternative A.

Effects of motorized use of plowed roads. The effects of plowed roads are similar to

those of groomed roads, except that the magnitude of the effect is usually greater. The

use of motorized vehicles on plowed roads can cause injury and death for wildlife,

especially in poor lighting conditions, at dusk and dawn, and during snowfall, and can

cause displacement from preferred habitats.

The use of plowed roads by wheeled-vehicles may increase wildlife-vehicle collisions

and displacement over current rates along the road segment from West Yellowstone to

Old Faithful. These effects would be increased relative to alternative B because

alternative C does not call for mass transit, nor does it prohibit late night travel. In

addition plowing the Moose-Wilson Road would potentially impact moose that winter

along this corridor.
IMPACTS OF IMPLEMENTING ALTERNATIVE C

311

Effects of nonmotorized use of groomed and designated ungroomed routes. The

primary effects of nonmotorized use on ungulates are displacement from preferred

habitats, especially geothermal areas that are important for winter survival in YNP, and

increased energy expenditures, including physiological stress, which may reduce

individuals’ chances of survival. Under alternative C, YNP increases nonmotorized

opportunities by grooming an additional 10 miles (from 37 miles to 47 miles) and adds 8

more miles after motorized use ceases late in the winter season. Ungroomed trails in

GTNP and the Parkway increase from 26 miles to 28 miles, and groomed trail increase 4

miles.

Overall, the potential for an increase in adverse effects is low because trails would not be

located in areas of high importance to wintering ungulates. Exceptions include trails

located near thermal areas (e.g., Mammoth Hot Springs or Old Faithful), or in other areas

of ungulate use in the winter (e.g., moose near the Gros Ventre campground trail).

Similar to alternative B, these trails could have minor effects on ungulates.

Effects of unregulated backcountry nonmotorized use. Unregulated backcountry

nonmotorized use is more random and infrequent relative to nonmotorized use on

designated routes. Consequently, although encounters between backcountry users and

ungulates may only occur sporadically, they can be especially disturbing and lead to

additional energy expenditure and stress that reduces animals’ chances of survival and

reproduction. Impacts under this alternative generally would be the same as in

alternative A. In GTNP moderate to major adverse impacts on bighorn sheep would

continue, as well as potential impacts to moose, elk, and bison on Blacktail Butte and

Wolff Ridge.

Effects of the presence and use of winter support facilities. Increases in human

activity associated with the presence of support facilities may displace species sensitive

to human disturbance. Alternative C proposes an increase in the number and size of

warming huts and other day-use facilities. In addition this alternative proposes the

establishment of winter campsites in the Old Faithful area. Warming huts and restrooms

would be located at popular ski trailheads, motorized staging areas, and areas where

existing facility size is currently inadequate (e.g., Tower, Norris, and Canyon). Warming

huts near ungulate winter range important to elk, deer, and bison would potentially

increase human use and consequently reduce habitat effectiveness. However, over time

the predictable nature of the recreation expected to occur in the area may allow species to

habituate to increased human activity. The effects of these huts on ungulates would be

the same for all alternatives.

Federally Protected Species

Effects of groomed roads and trails. Packed trails may influence wildlife movements

and distributions by facilitating travel into areas that would normally be inaccessible due

to deep snow. Under alternative C, GTNP and the Parkway would groom about 66 miles,

an increase of about 30 miles over current management and 4 miles for nonmotorized
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

312

use. The new groomed motorized route would begin near the south boundary, follow the

Gros Ventre River, and then parallel the eastern boundary up to Moran. GTNP would

also groom new nonmotorized trails in the Gros Ventre River Campground and at Two

Ocean Lake. YNP would groom 164 miles, a decrease of 20 miles, and 47 miles for

nonmotorized use, an increase of 10 miles over current management.

Overall effects related to packed trails would increase as compared to alternative A,

especially in GTNP. Because the area of the new groomed snowmobile route in the

southern part of the park is not lynx habitat, impacts on lynx would only be expected to

increase in the Two Ocean Lake area.

Effects of motorized oversnow use of groomed and ungroomed roads and trails. The

use of motorized oversnow vehicles can cause displacement from preferred habitats. To

date oversnow motorized vehicles have not killed any federally listed species.

In GTNP the proposed snowmobile trail from Jackson along the east boundary of the

park to Moran could result in a significant increase in snowmobiling activity along the

Gros Ventre River, up to the Triangle Ranch along the eastern park boundary, and along

US 89 to Moran Junction. This trail would introduce snowmobiling use adjacent to areas

such as Elk Ranch, Uhl Hill, and Wolff Ridge, which are important winter range for

ungulates, and subsequently, wolves. Snowmobiling near these areas could result in

human-wolf interactions, displacement of prey (primarily elk), and consequently

displacement of wolves. The periodic departure of the CDST from the highway shoulder

to scenic diversions could also displace lynx and snowshoe hares. Effects to other

species are similar to those in alternative A.

Effects of plowed roads. Road plowing may cause habitat fragmentation by creating

structural barriers (i.e., snow berms) to wildlife movements (Aune 1981). In addition

similar to groomed roads, plowed roads may influence wildlife movements and

distributions by facilitating travel for wildlife into areas that would normally be

inaccessible due to deep snow. Under alternative C the effects described above are

associated with about 106 miles of road in YNP, an increase of 30 miles over existing

management to accommodate private wheeled-vehicles from West Entrance to Old

Faithful. The miles of plowed roads in GTNP and the Parkway would increase

marginally from about 100 miles to 104 miles to allow for wheeled-vehicle access on the

Moose-Wilson Road.

Impacts of plowed roads on federally protected species would be the same as alternative

A.

Effects of motorized use of plowed roads. The effects of traffic on plowed roads are

similar to those of traffic on groomed roads, except that the magnitude of the effect is

usually greater. The use of motorized vehicles on plowed roads can cause injury and

death for wildlife, especially in poor lighting conditions, at dusk and dawn, and during

snowfall, and can cause displacement from preferred habitats.
IMPACTS OF IMPLEMENTING ALTERNATIVE C

313

The road from West Yellowstone to Old Faithful would be plowed and open to public

access two weeks earlier under this alternative, potentially leading to an increase in

human-bear interactions during the pre-denning period. However, none of the radiocollared bears in YNP have denned along this road segment, and only about 10% of bears

are still active at this time (Haroldson et al. in prep.). This alternative also calls for

extending the length of the winter use season from the South Entrance to West Thumb by

two weeks from mid-March to the beginning of April. This period of time overlaps with

den emergence for bears (about 65% of bears are out of their dens by April (Haroldson et

al. in prep.). Consequently, this alternative feature may have minor to moderate adverse

effects on bears, including displacement and habituation of bears to human foods and

garbage associated with human developments. This may lead to more bear-human

confrontations and management actions. Effects related to plowed roads in GTNP would

remain the same as under current management.

Other impacts related to displacement would be the same as those under alternative A.

Collision impacts may be greater than those under alternative A because the roads are

open for a longer period.

Effects of nonmotorized use on groomed and designated ungroomed routes. The

primary effects of nonmotorized use on wildlife are displacement from preferred habitats

and increased energy expenditures, including physiological stress, which may reduce

individuals’ chances of survival. Under alternative C, YNP increases nonmotorized

opportunities by grooming an additional 10 miles (from 37 miles to 47 miles) and adds 8

more miles after motorized use ceases late in the winter season. Ungroomed trails in

GTNP and the Parkway increase from 26 miles to 28 miles and groomed trails increase

by 4 miles.

Overall, the potential for an increase in adverse effects to wolves is low because trails

would not be located in areas of high importance to wintering ungulates and

consequently, wolves. Exceptions include trails located near thermal areas (e.g.,

Mammoth Hot Springs or Old Faithful), or in other areas of ungulate use in the winter

(e.g., the Gros Ventre campground trail). Lynx could be impacted by trails at Two Ocean

Lake. Furthermore, when warranted the parks may close any area where federally

protected species are observed. Other effects are the same as those under alternative A.

Effects of unregulated backcountry nonmotorized use. Unregulated backcountry

nonmotorized use is more random and infrequent relative to nonmotorized use on

designated routes. Consequently, although encounters between backcountry users and

federally protected wildlife species may only occur sporadically, they may cause

displacement and additional energy expenditure and stress that reduces animals’ chances

of survival and reproduction.

Impacts under this alternative generally would be the same as in alternative A.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

314

Presence and use of winter support facilities. Warming huts and campgrounds can

cause habituation in some wildlife species by the presence of human food and garbage,

and lead to human-wildlife conflicts. In addition increases in human activity associated

with the presence of support facilities may displace species sensitive to human

disturbance. Alternative C proposes an increase in the number and size of warming huts

and other day use facilities. In addition this alternative proposes the establishment of

winter campsites in the Old Faithful area. Warming huts and restrooms would be located

at popular ski trailheads, motorized staging areas, and areas where existing facility size is

currently inadequate or nonexistent (e.g., Tower, Norris, and Canyon). Warming huts

near ungulate winter range important to elk, deer, and bison would potentially increase

human use and consequently reduce habitat effectiveness. Displacement of ungulates

could lead to displacement of wolves. However, over time the predictable nature of the

recreation expected to occur in the area may allow ungulates to habituate to the increase

in human activity. Additional developments in or near lynx habitat could potentially

displace lynx.

The construction of new campsites at Old Faithful, new and enlarged warming huts at

Norris and Tower, and additional support facilities at GTNP (e.g., at Two Ocean Lake)

may increase human use in those areas and may lead to minor negative effects on late

winter and spring food availability for emerging bears in an area of currently low human

use. Garbage and human foods improperly stored at park winter use destination areas

can lead to adverse impacts on bears before and after the winter use season.

To date YNP does not have adequate winter garbage storage facilities, but will rectify

this issue by constructing a winter garbage storage facility that is wildlife-proof in the

Old Faithful, Grant, Lake, and Canyon areas (a feature of all alternatives). Similar to

alternative B, the availability of plowed roads into the park’s interior would allow for

garbage removal, thus decreasing problems associated with habituation.

Compared to current management, impacts related to displacement would be greater due

to the increase in number of facilities. Specifically, huts located in thermally influenced

ungulate winter range could displace ungulates, and thus affect bison and elk carcass

availability, important spring foods for grizzly bears. Because ungulates have been

known to habituate to predictable human activities, any displacement would most likely

be short term. The extension of the winter use season combined with increased human

activity near new support areas may lead to more bear-human conflicts.

Species of Special Concern

Effects of groomed roads and trails. Packed trails may influence wildlife movements

and distributions by:

• Facilitating travel into areas that would normally be inaccessible due to deep snow

• Inhibiting foraging activities of carnivores that tunnel beneath the snow to hunt subnivian

prey

• Reducing subnivian prey availability by increasing mortality of these small mammals.
IMPACTS OF IMPLEMENTING ALTERNATIVE C

315

Under alternative C, GTNP and the Parkway would groom about 66 miles, an increase of

about 30 miles over current management, and 4 miles for nonmotorized use. The new

groomed motorized route will begin near the south boundary, follow the Gros Ventre

River, and then parallel the eastern boundary up to Moran. GTNP would also groom new

nonmotorized trails in the Gros Ventre River Campground and at Two Ocean Lake.

YNP would groom 164 miles for motorized use, a decrease of 20 miles, and 47 miles for

nonmotorized use, an increase of 10 miles over current management.

Impacts discussed under alternative A would potentially increase, especially in GTNP.

Additional miles of groomed trail in GTNP could increase impacts on martens and

fishers. New groomed trails are not in swan habitat.

Effects of motorized oversnow use of groomed and ungroomed roads and trails. The

most likely impacts to park species of special concern are displacement from preferred

habitats, and degradation of the aquatic environment from pollutants in the snowpack.

Documented mortality caused by collisions with oversnow vehicles in the parks is rare.

In 10 years only one of these species (a marten) was reportedly killed by a snowmobile in

YNP (Gunther et al. 1998).

Impacts would increase relative to alternative A. The separation of the CDST from the

plowed roadway would cumulatively increase displacement impacts associated with the

use of both oversnow and wheeled-vehicles.

See Water and Aquatic Resources, Chapter IV for an assessment of the impacts of

exhaust on the aquatic environment in the parks.

Effects of plowed roads. Similar to groomed roads, plowed roads also provide an

energy efficient mechanism for wildlife movements. Under alternative C the effects

described above are associated with about 106 miles of road in YNP, an increase of 30

miles over existing management to accommodate private wheeled-vehicles from West

Entrance to Old Faithful. The miles of plowed roads in GTNP and the Parkway would

increase marginally from about 100 miles to 104 miles to allow for wheeled-vehicle

access on the Moose-Wilson Road.

Impacts related to plowed roads would increase slightly in YNP compared to alternative

A. Effects related to plowed roads in GTNP would remain the same as under current

management.

Effects of motorized use of plowed roads. The most likely impact to park species of

special concern is displacement from preferred habitats and mortality caused by

collisions.

Under alternative C impacts related to plowed roads would slightly increase in YNP as

compared to alternative A. In particular swans that winter in open water habitats along
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

316

the plowed road from West Yellowstone to Old Faithful may be disturbed by the increase

in wheeled-vehicle traffic along this route. If vehicles stop for people to get out to view

swans, swans could be adversely impacted by displacement.

Effects of nonmotorized use on groomed and ungroomed designated routes. The

primary effects of nonmotorized use are displacement from preferred habitats, and

increased energy expenditures, including physiological stress, which may reduce

individuals’ chances of survival. Under alternative C YNP increases nonmotorized

opportunities by grooming an additional 10 miles (from 37 miles to 47 miles) and adds 8

more miles after motorized use ceases late in the winter season. GTNP and the Parkway

increase ungroomed trails from 26 miles to 28 miles and add 4 miles of groomed trail.

Although the above effects may be increased due to the addition of nonmotorized routes,

they are expected to be relatively minor because most routes would not be located in

areas critical to species of special concern (e.g., adjacent to open water habitats and

ungulate winter ranges).

Unregulated backcountry nonmotorized use. Unregulated backcountry nonmotorized

use is more random and infrequent than nonmotorized use on designated routes.

Consequently, although encounters between backcountry users and species of special

concern may occur sporadically, they can be especially disturbing and lead to additional

energy expenditure and stress that reduces animals’ chances of survival and reproduction.

Impacts are generally as stated in alternative A — negligible to minor. If activity by

species of concern is known to occur in an area, park managers can close the area to

human activity to prevent disturbance.

Presence and use of winter support facilities. The primary effects of warming huts and

campgrounds on species of special concern in the park are associated with increases in

human activity and the subsequent disturbance and displacement of species or their prey.

Alternative C proposes an increase in the number and size of warming huts and other

day-use facilities. In addition this alternative proposes the establishment of winter

campsites in the Old Faithful area. Warming huts and restrooms would be located at

popular ski trailheads, motorized staging areas, and areas where existing facility size is

currently inadequate (e.g., Tower, Norris, and Canyon).

Compared to current management, impacts related to displacement would be greater due

to the increase in facilities. Specifically, huts located in thermally influenced ungulate

winter range could displace ungulates, and thus affect bison and elk carcass availability

for wolverines, fishers, and marten. Because ungulates have been known to habituate to

predictable human activities, any displacement would most likely be short term. Impacts

on other species of special concern would be the same as those under alternative A.
IMPACTS OF IMPLEMENTING ALTERNATIVE C

317

Conclusion

This alternative maximizes winter visitor opportunities for a range of experiences, while

emphasizing motorized recreation. Consequently, effects on wildlife associated with

oversnow and wheeled-vehicles increase. Plowing the road from Yellowstone to Old

Faithful to accommodate private vehicles may lead to more collisions than under

alternative B because there are no provisions for mass transit or restrictions on late night

travel. Effects related to groomed trails and snowmobiles increase substantially in

GTNP. The establishment of a groomed snowmobile trail from GTNP’s south boundary

to Moran along the eastern park boundary may negatively impact wildlife, including

ungulates, wolves, and lynx. Periodic diversions of the CDST to points of interest may

affect moose and lynx in the northern part of the park. In YNP the extension of the

winter use season from mid-March to the beginning of April from the South Entrance to

West Thumb combined with an increase in winter support facilities may result in an

increase in grizzly bear–human conflicts. Effects may be mitigated to a degree by an

increased emphasis on visitor education and interpretive opportunities, as well as

increased administrative capability.

Although impacts on populations resulting from winter recreation are neither long term

nor significant, impacts on individual members of the population can be important,

leading to death either directly from collisions or continued harassment, or indirectly

through management actions taken as a response to habituation to human presence and

food. Although concerned about impacts on individuals, the NPS primarily provides for

the protection of native animals populations from management actions (with the

exception of federally protected species). For example, see Chapter II in NPS 77,

Natural Resources Management.

Ungulates

• Effects of groomed roads and trails on animal movements – unknown if and to what extent

beneficial effects outweigh negative effects. Effects would increase in GTNP and decrease

in YNP relative to alternative A.

• Effects of motorized oversnow use of groomed and ungroomed roads and trails on: 1)

mortality caused by collisions – adverse, negligible, and short term, and 2) displacement

from preferred habitats – adverse, moderate to major, and short term. In GTNP effects

would increase relative to alternative A. In YNP effects would decrease [relative to

alternative A].

• Effects of plowed roads on: 1) habitat fragmentation – effects in YNP would increase over

alternative A — adverse, minor, and short term; in GTNP effects would remain the same;

and 2) animal movements – unknown if and to what extent beneficial effects outweigh

negative effects; any effects would remain essentially the same as those associated with

groomed roads in alternative A.

• Effects of motorized use of plowed roads on: 1) mortality caused by collisions – adverse,

minor, and short term; and 2) displacement from preferred habitats – adverse, moderate,

and long term. Effects would increase relative to alternatives A and B in YNP and remain

the same in GTNP.

• Effects of nonmotorized use of groomed and designated ungroomed routes on displacement

from preferred habitats – adverse, minor, and short term. Generally the same as alternative

A, but may increase slightly.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

318

• Effects of unregulated backcountry nonmotorized use on displacement from preferred

habitats – adverse, moderate, and short term. Impacts to bighorn sheep in GTNP would be

moderate to major and long term if no mitigation is applied. Same as alternative A.

• Effects of the presence and use of winter support facilities on displacement – adverse,

minor, and short term. May increase slightly relative to alternative A because more huts

are proposed.

Federally Protected Species

• Effects of groomed roads and trails on animal movements: 1) bald eagles, grizzly bears,

and wolves – no effect; and 2) lynx – adverse, negligible to major, and short term,

depending upon lynx distribution and abundance in the parks. Increased groomed trails in

GTNP would increase effects to lynx relative to alternative A.

• Effects of motorized oversnow use of groomed and ungroomed roads and trails on

displacement from preferred habitats – adverse, minor, and short term (wolves and lynx),

adverse, negligible, and short term (bald eagles), and no effect (grizzly bear). Effects may

increase for wolves relative to alternative A.

• Effects of plowed roads on: 1) habitat fragmentation – no effect on any of the listed

species; and 2) animal movements – no known effect on any of the listed species. Same as

alternative A.

• Effects of motorized use of plowed roads on: 1) mortality caused by collisions – effects

may increase over alternative A – adverse, negligible, and short term on bald eagles;

adverse, minor, and short term on wolves, grizzlies; no known effect to date on lynx; and

2) displacement from preferred habitats – adverse, negligible, and short term on bald

eagles; no known effect to date on wolves and lynx; adverse and minor to moderate for

grizzly bears because of the longer winter use season.

• Effects of nonmotorized use of groomed and designated ungroomed routes on displacement

from preferred habitats – adverse, negligible, and short term on bald eagles; no effect on

grizzly bears; no known effect to date on wolves; minor adverse effect on lynx. Same as

alternative A.

• Effects of unregulated backcountry nonmotorized use on displacement from preferred

habitats – adverse, minor, and short term on bald eagles; adverse, negligible, and short term

on grizzly bears; adverse, minor, and short term on wolves; no known effect to date on

lynx. Same as alternative A.

• Effects of the presence and use of winter support facilities on displacement – no affect on

bald eagles; adverse, minor, and short term on grizzly bears (with mitigation) and wolves;

unknown effect on lynx. May slightly increase relative to alternative A because more huts

are proposed.

Species of Special Concern

• Effects of groomed roads and trails on 1) animal movements – no known effect on

wolverines; adverse, negligible, and short term on fishers and martens; no effect on otters,

swans, reptiles, amphibians, and fish; 2) foraging activities – adverse, negligible, and short

term on marten; no effect on the other species; and 3) subnivian prey availability —

adverse, negligible, and short term on marten; no effect on the other species. Impacts

would generally increase relative to alternative A, especially in GTNP.

• Effects of motorized oversnow use of groomed and ungroomed roads and trails on

displacement – no known effect on wolverine; adverse, negligible, short term on fishers,

marten; no effect on otters, reptiles, amphibians, fish; adverse, minor, short term on swans.

Impacts would increase relative to alternative A, especially in GTNP.

• Effects of plowed roads on animal movements – no known effect on wolverines, fishers,

and martens; no effect on otters, swans, reptiles, amphibians, and fish. Slight increase in

effects in YNP relative to alternative A, no change in GTNP relative to alternative A.

• Effects of motorized use of plowed roads on 1) displacement from preferred habitats –

adverse, negligible, and short term on wolverines, fishers, and martens; no effect on otters,

reptiles, amphibians, and fish; adverse, negligible, and short term on swans; and 2)
IMPACTS OF IMPLEMENTING ALTERNATIVE C

319

mortality from collisions — adverse, negligible, and short term on otters and martens; no

effect to date on other species. Effects may increase slightly relative to alternative A in

YNP.

• Effects of nonmotorized use of groomed and designated ungroomed routes on displacement

from preferred habitats – no effect on wolverines; no known effect on fishers, martens, and

otters; adverse, minor, and short term on swans; adverse, negligible, and short term on

sagebrush lizard; no effect on rubber boa, amphibians, and fish. Same as alternative A.

• Effects of unregulated backcountry nonmotorized use on displacement from preferred

habitats – adverse, negligible, and short term on wolverines and sagebrush lizard; no

known effect on fishers, martens, and otters; adverse, minor, and short term on swans; no

effect on rubber boa, amphibians, and fish. Same as alternative A.

• Effects of the presence and use of winter support facilities on displacement of potential

prey (carcass) availability – adverse, minor to moderate, and short term on wolverines,

fishers, and martens; no effect on swans, rubber boa, amphibians, and fish; no known effect

on otters; adverse, minor, and short term on sagebrush lizard. May slightly increase

relative to alternative A because more huts are proposed.

Mitigation

• In YNP campground use season should not be extended, and backcountry permits should

not be issued to mitigate any possible impacts on grizzly bears due to the extended winter

use season on the West Entrance to Old Faithful road.

• The implementation of current Bear Management Area (BMA) human use restrictions

would help alleviate the risks of bear-human confrontations in spring habitats.

• Where motorized use occurs near active trumpeter swan habitats (i.e., open water), the

route would be signed or plowed to prevent vehicles from stopping.

• Backcountry monitoring and administration should be implemented in GTNP. Additional

area closures could be imposed if monitoring indicates such a closure was warranted for the

protection of wintering bighorn sheep and moose.

• The effects of winter use on resident wolves should be monitored. Areas would be closed

as necessary to protect winter and denning habitats.

• The entire length of the trail from Jackson to Moran Junction and from Moran Junction to

Flagg Ranch should be patrolled to ensure that snowmobilers remain on the trail and do not

illegally enter areas that are important winter range.

• The effects of the warming hut in the Two Ocean Lakes area would be monitored. If

human-bear conflicts arise, close the facility.

• The use of groomed and plowed surfaces by bison and other ungulates would continue to

be monitored.

• Snow track surveys for carnivores, including lynx, on both groomed and ungroomed routes

would be conducted.

Effects on Natural Soundscape

Audibility Analysis — Combined Effects of All Wheeled and Oversnow Vehicles

Table 95 presents the acres of park land by road segment where any wheeled or

oversnow vehicle noise would be audible under the two background conditions,

“average” and “quiet,” as defined in the Assumptions and Methodologies section of this

chapter. For each background condition, acreage is presented for three categories of

audibility: 1) audible for any amount of time (labeled “audible at all”); 2) audible for

10% of the time or more; and 3) audible for 50% of the time or more. Appendix M

contains tables with distances to audibility for each segment for each alternative.
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ENVIRONMENTAL CONSEQUENCES

320

Alternative C features the plowed road from the West Entrance of YNP to Old Faithful,

plowing from Mammoth to Madison for part of the season, snowcoach-only use from

Canyon Village to Fishing Bridge for part of the season, and the addition of a new

snowmobile trail in Antelope Flats in GTNP. It also requires that all snowplanes on

Jackson Lake meet the current limit of 86 dBA at 50 feet.

The results for alternative C show that for the “average” background conditions, wheeled

and oversnow vehicles would be audible to some degree for over 188,000 acres in the

three park units. For over 80,000 of those acres, wheeled or oversnow vehicles would be

audible for at least 10% of the time during the day. For over 27,000 of those acres, they

would be audible for at least half of the time during the day. These acreage totals

increase by 9%, 14%, and 20% for the “quiet” background conditions for the three

audibility categories, respectively.

The segment from Moran Junction to the South Entrance of GTNP carries a great deal of

wheeled-vehicle traffic unrelated to the alternatives and contributes the greatest to the

total acreage values for all three audibility categories. These amounts remain almost

constant for all the alternatives.

The plowed road from Mammoth to the Northeast Entrance is a major contributor to the

“audible at all” acreage (and to a lesser extent “audible 10% or more”), which remains

virtually unchanged across all the alternatives.

Other key segments for all three audibility categories are from West Thumb to Flagg

Ranch, from Fishing Bridge to West Thumb, from Old Faithful to West Thumb, and from

Canyon Village to Fishing Bridge, all of which increase compared to the no action

alternative.

Other major segments for the “audible at all” categories are the Antelope Flats

snowmobile route and Jackson Lake with its snowplanes and snowmobiles. Snowplanes

and snowmobiles on Jackson Lake are also major contributors to the “audible at all”

categories, although the acreage is greatly reduced over the no action alternative because

of the 86 dBA limit on snowplane sound levels.

The audibility acreage is greatly reduced for the West Entrance to Madison and Madison

to Old Faithful segments due to the replacement of oversnow vehicles with wheeledvehicles on the plowed road. For YNP the 50% time audible average increases by 29%

over the no action alternative for average background conditions, due largely to increased

snowmobile volumes on other road segments.
IMPACTS OF IMPLEMENTING ALTERNATIVE C

321

Table 95. Acres of park land affected by vehicle audibility for alternative C.

With Average Background

Conditions

With Quiet Background

Conditions

Road Segment Miles

Audible

at all

Audible

10% of

the time

or more

Audible

50% of

the time

or more

Audible

at all

Audible

10% of

the time

or more

Audible

50% of

the time

or more

1. Mammoth to Northeast Entrance 47 16,126 5,445 0 16,822 6,342 0

2. Mammoth to Norris 21 11,400 761 0 12,372 1,043 0

3. West Entrance to Madison 14 5,260 78 0 5,555 91 0

4. Madison to Norris 14 6,748 268 0 7,142 296 0

5. Norris to Canyon Village 12 5,434 1,677 0 5,672 2,318 0

6. Canyon Village to Fishing Bridge 16 10,504 8,092 2,200 11,432 8,896 2,637

7. Fishing Bridge to East Entrance 27 12,692 5,268 0 13,744 6,588 0

8. Fishing Bridge to West Thumb 21 16,888 12,886 5,153 18,687 14,183 6,249

9. Madison to Old Faithful 16 6,157 1,660 0 6,521 1,927 0

10. Old Faithful to West Thumb 17 8,012 6,595 2,814 9,513 7,232 4,029

11. West Thumb to Flagg Ranch 24 13,788 10,767 5,133 16,018 11,989 6,931

12. Grassy Lake Road 7.6 3,033 0 0 3,303 0 0

13. Flagg Ranch to Colter Bay 15.6 7,731 3,453 0 8,443 3,859 0

14. Colter Bay to Moran Junction 10.2 4,647 2,460 0 5,040 2,694 0

15. Moran Junction to East Entrance 2 1,226 765 497 1,320 876 542

16. Moran Junction to South Entrance 26 21,714 14,812 11,293 23,842 17,207 11,996

17. Teton Park Road 15 7,805 0 0 8,512 0 0

18. Moose-Wilson Road 2.5 672 0 0 708 0 0

19. Antelope Flats Snowmobile Route 30 17,429 0 0 19,016 0 0

20. Jackson Lake 9.7 10,980 5,577 0 12,300 6,420 0

TOTAL 188,245 80,564 27,091 205,961 91,959 32,385

Average sound level analysis

To give a sense of the effect of the number of oversnow or wheeled-vehicles on a road

segment, and their speed and sound level, Table 96 shows the computed hourly

equivalent or “average” sound level (Leq) over the daytime period. Levels are shown for

each road segment at two distances, 100 feet and 4,000 feet, and for both open and

forested terrain. These hourly Leq values do not have the background sound level added

in. Also, they cannot be compared against the background levels to assess audibility,

since Leq represents a long-term average of both quiet and loud moments.

The hourly Leq at 100 feet are highest for the segment representing Jackson Lake, plus the

YNP segments of West Thumb to Flagg Ranch, Fishing Bridge to West Thumb, Old

Faithful to West Thumb, and Canyon Village to Fishing Bridge. At a distance of 4,000
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

322

feet away, these latter four segments along with the GTNP segments from Moran

Junction to both the East and South Entrances have the highest Leq.

There are major 16 dB to 18 dB reductions in the Leq for the West Entrance to Madison

and Madison to Old Faithful segments that would be plowed.

Table 96. Average hourly Leq from wheeled and oversnow vehicle noise at two

distances to each road segment for alternative C.

Leq at Distance (dBA)

Open Terrain Forested Terrain

Road Segment 100 feet 4,000 feet 100 feet 4,000 feet

1. Mammoth to Northeast Entrance 35 2 33 0

2. Mammoth to Norris 46 7 45 0

3. West Entrance to Madison 36 4 34 0

4. Madison to Norris 45 6 44 0

5. Norris to Canyon Village 46 7 45 0

6. Canyon Village to Fishing Bridge 53 13 51 5

7. Fishing Bridge to East Entrance 47 7 45 0

8. Fishing Bridge to West Thumb 53 13 51 5

9. Madison to Old Faithful 38 5 36 0

10. Old Faithful to West Thumb 54 14 52 6

11. West Thumb to Flagg Ranch 54 14 52 6

12. Grassy Lake Road 42 2 41 0

13. Flagg Ranch to Colter Bay 44 7 42 0

14. Colter Bay to Moran Junction 45 9 43 1

15. Moran Junction to East Entrance 47 13 45 5

16. Moran Junction to South Entrance 46 14 44 6

17. Teton Park Road 39 0 37 0

18. Moose-Wilson Road 27 0 25 0

19. Antelope Flats Snowmobile Route 39 0 37 0

20. Jackson Lake 54 8 52 0

Conclusion

Alternative C impacts about 104% of the acreage impacted by the no action alternative

for the “audible at all” categories. The alternative impacts about 86% for the “audible

10% of the time or more” categories. For the “audible 50% or more” categories, the

acreage are 115% and 122% higher than for the no action alternative (for the “average”

and “quiet” backgrounds, respectively)

The increase in acreage for the “audible 50% of the time or more” categories relative to

the no action alternative come from increases on the YNP segments of West Thumb to

Flagg Ranch, Fishing Bridge to West Thumb, Old Faithful to West Thumb, and Canyon
IMPACTS OF IMPLEMENTING ALTERNATIVE C

323

Village to Fishing Bridge. These increases override the decreases on the plowed road

segments from the West Entrance of YNP to Old Faithful.

Effects on Cultural Resources

The effects on cultural resources would be the same as those described in alternative B.

Conclusion

None of the actions described would adversely affect cultural resources.

Effects on Visitor Access and Circulation

Access

This alternative is similar to alternative B, except that the shuttle system is not a feature.

Without the shuttle system, this alternative substantially reduces access to the park from

840 daily weekend visitors in February to about 220 given the same private vehicle

access to Old Faithful described in alternative B. Roadway segments between Mammoth

and Madison would be plowed from mid-February to mid-March, providing private

vehicle access to the Norris destination area. Travel on these segments would be limited

to traffic passing through the park, as private vehicle parking at Norris would be limited

to 120 spaces (about 50% of summer season capacity).

Actions associated with this alternative that affect GTNP access include plowing the

Moose-Wilson Road and maintaining a continuous snowmobile trail parallel to roadways

on the eastern edge of the park between Jackson and Moran Junction, providing a

connection to the CDST. Demand estimates are not available for this new snowmobile

trail, but it is believed that many snowmobile enthusiasts would take advantage of this

new regional access route to GTNP and the CDST. This alternative would not alter

current park circulation patterns. Wheeled-vehicle circulation also would be enhanced

through this alternative by providing continuous access along Moose-Wilson Road.

Closing YNP’s West Entrance to oversnow access could enhance the importance of

access for snowmobiles through GTNP and the Parkway to YNP. Winter scenery and

wildlife in YNP will continue to attract potential visitors. Access for the number of

snowmobile and snowcoach visitors currently using the West Entrance could shift to the

South Entrance. The staging for oversnow opportunities from these routes could increase

use at Flagg Ranch. Table 97 depicts reasonably foreseeable distribution of vehicle use

under alternative C. It shows a loss of 554 snowmobile trips from West Yellowstone to

Madison and 489 from Madison to Old Faithful. There would be a net decrease of 20%

in snowmobile vehicle-miles traveled in the three park units and a net increase of 17%

wheeled-vehicle-miles traveled. Snowcoach miles traveled would decrease by 42%.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

324

Table 97. Alternative C motorized use.

Average Daily Vehicle Use January-February

Road Segment Autos Vans Snowcoaches Snowmobiles Buses

Mammoth to Northeast Entrance No change from current condition

Mammoth to Norris until 2/2938 0 0 4 56 0

West Entrance to Madison 60 10 0 0 2

Madison to Norris 0 0 4 42 0

Norris to Canyon Village until 2/29 0 0 4 56 0

Canyon Village to Fishing Bridge

before 2/29

0 0 3 242 0

Fishing Bridge to East Entrance 0 0 0 67 0

Fishing Bridge to West Thumb 0 0 3 248 0

Madison to Old Faithful 91 14 0 0 2

Old Faithful to West Thumb 0 0 4 338 0

West Thumb to Flagg Ranch 0 0 4 322 0

Grassy Lake Road No change from current condition

Flagg Ranch to Colter Bay No change from current condition

Colter Bay to Moran Junction No change from current condition

Moran Junction to East Entrance No change from current condition

Moran Junction to South Entrance No change from current condition

Teton Park Road No change from current condition

Moose-Wilson Road 10 0 0 0 0

Antelope Flats Snowmobile Route 0 0 0 25 0

Concession Services

Impacts on concessions would be the same as those described in alternative B, although

the late season plowing would make access from Mammoth to Madison, thence to West

Yellowstone and Old Faithful, easier for concessioners and more attractive to visitors.

Conclusion

This alternative would result in major adverse impacts by closing visitor access to about

74% of the average daily weekend visitors currently entering the park through the West

Entrance and West Yellowstone; a reduction from 840 daily weekend visitors currently to

220. Although plowed roads would allow for wheeled-vehicle access, the lack of

available parking at Old Faithful would result in an overall reduction in daily winter

visitor use. There would be minor to moderate beneficial impacts on snowmobile access

(depending upon actual use) from Jackson and Dubois to GTNP and the Parkway, and

north into YNP.

 

38 After February 29 snowcoach only from Norris to Canyon and Fishing Bridge; road plowed from

Mammoth to Madison Junction.
IMPACTS OF IMPLEMENTING ALTERNATIVE C

325

Effects on Visitor Experience — Yellowstone National Park

The amount and type of winter visitor opportunities offered in YNP under alternative C

are provided in Table 98.

Table 98. YNP Visitor opportunities available under alternative C.

Opportunities

Miles

or

Areas

Increase/

Decrease

Late

Season

Increase/

Decrease Length of Season

Groomed motorized

route

154 -30 111 -35.3 South Entrance MidDecember to April + 2 weeks

Groomed motorized

route snowcoach only

0 0 28.8 +28.8 Mid-December to Mid-March

Groomed motorized

trail

10 +10 10 +10 Mid-December to Mid-March

Plowed route 106 +30 65.3 +35.3 No fall closure + 6 weeks

Groomed nonmotorized 47 +10 55 +8 Mid-December to Mid-March

Warming huts 9 3 9 3 Mid-December to Mid-March

Backcountry 2.2

million

acres

0 2.2

million

acres

0 Contingent on snowfall in

northern portion of park

Visitor Satisfaction and Experience

Opportunities to view wildlife. The impacts associated with this topic would be the

same as alternative B, except that visitors traveling from West Yellowstone to Old

Faithful would have the ability to stop at their own discretion to view wildlife.

Opportunities to view scenery. From mid-February to mid-March snow would obstruct

some views along the road segments from to Mammoth to Norris, Norris to Madison, and

from Madison to Old Faithful. These impacts would occur primarily in areas where steep

up-slopes occur adjacent to roadways. This type of terrain occurs intermittently and

generally on one side of the road for about 5 miles along the road segment from

Mammoth to Norris Junction. It also occurs intermittently for about 4 miles along the

road segment from Norris Junction to Madison Junction. Snow berms in this type of

terrain could exceed 12 feet and would obstruct views. In areas where the terrain is open

and flat, snow berms generally would be less than 6 feet (assuming an accumulation of

95 inches). Snow blowing and removal could mitigate these impacts in some areas.

These impacts would vary with the time of year, the type of vehicle used and the amount

of snowfall received. The impacts to viewing opportunities on the road segments from

West Entrance to Madison and Madison to Old Faithful would be the same as alternative

B.

Safety (the safe behavior of others). Same as alternative B, except the use of private

vehicles on the roads from West Entrance to Old Faithful could increase safety problems

associated with winter driving.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

326

The late season snowcoach-only travel zone would lessen the chance for snowmobile and

skier conflict resulting in fewer motor vehicle accidents in that area.

The multiple transportation modes and seasons offered in this alternative make it very

complex. Visitors traveling in private cars could be unprepared to handle the harsh

winter environment. Drivers could be inexperienced in winter driving or automobiles not

equipped to handle winter driving conditions.

Quality of the groomed surface. Same as alternative B.

The availability of winter activities or experiences. This alternative would provide

wheeled-vehicle access from West Yellowstone to Old Faithful. Unlike the shuttle

system described in alternative B, this alternative allows access by private vehicle.

Because the parking at Old Faithful is very limited, the actions described under this

alternative would substantially limit the number of winter visitors to that area. This

alternative would afford a longer use season for travelers from the West Entrance to Old

Faithful by eliminating the current fall road closure.

Under this alternative, the road north of Colter Bay in GTNP would be not be plowed.

This would increase the one-way, oversnow distance to Old Faithful by 20 miles. This

action could make the trip to Old Faithful via the South Entrance more difficult for

oversnow vehicle travelers.

In mid- to late February, the road would be plowed from Mammoth to Norris Junction

and from Norris Junction to Madison Junction. Concurrent with the road plowing would

be a snowcoach-only travel zone from Norris Junction to Canyon and south to Fishing

Bridge. This option would provide skiers with additional winter recreation opportunities.

However, one month of snowmobiling opportunities would be lost to this user group.

Although this alternative affords new opportunities, logistically there would be negative

effect on the overall visitor experience. Because of the different modes of transportation

required, visitors, particularly from the North Entrance, would find trip planning and

implementation complex. Parking and staging area limitations at Madison and Norris

Junction could further limit visitor opportunities.

Additional winter experiences would be offered by increasing the number of groomed

motorized and nonmotorized trail opportunities, and by providing winter camping

opportunities at Old Faithful.
IMPACTS OF IMPLEMENTING ALTERNATIVE C

327

Availability of information. Same as in alternative B.

Quiet and Solitude. Opportunities for quiet and solitude would increase for skiers and

snowcoach riders during the late season on the road segments from Norris to Canyon and

south to Fishing Bridge. If snowmachine use of the West Entrance to Madison to Old

Faithful roads were to be displaced to the remainder of the park, opportunities for quiet

and solitude on the east side of YNP could decrease.

Clean air. Same as no action, except on plowed road sections. Visitors to these areas

would encounter improved air quality because of reduced traffic volumes and the

elimination of snowmobiles on these road segments.

Conclusion

The plowing of roads proposed under this alternative would eliminate or detract from

several characteristics of the winter experience for many snowmobile and snowcoach

riders (about 48% of all winter visitors in 1999-2000). This would result in major

adverse impacts on this user group. The creation of snow berms along plowed roadways

would cause moderate adverse impacts on scenery viewing opportunities along some

roadways.

The addition of motorized and nonmotorized trails would increase available winter

experiences for many visitors and result in direct moderate beneficial impacts. This

alternative would have moderate adverse effects on opportunities to experience solitude

and quiet (except during the late season) in most of the park areas. Because of the late

season and “clean and quiet” snowcoach only zone, visitors to the Canyon area would

experience moderate to major beneficial improvements in opportunities to experience

clean air and solitude. Opportunities to experience clean air would also improve on the

roads from West Entrance to Old Faithful.

Visitors who are unable, cannot afford, or do not wish to ride a snowmobile or

snowcoach would have access via private automobile to Old Faithful. Because this type

of winter experience at Old Faithful has not previously been available, alternative C

would result in an increase in winter opportunities for visitors in this user group (as

compared to alternative A). Moderate adverse impacts would occur due to the

complexity of the alternative actions and the limited parking available at Madison,

Norris, and Old Faithful. Overall, few improvements to visitor experience are expected

under this alternative.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

328

Effects on Visitor Experience — Grand Teton National Park and the

Parkway

The amount and type of winter visitor opportunities offered in GTNP under alternative C

are provided in Table 99.

Table 99. GTNP Visitor opportunities available under alternative C.

Opportunities

Miles

or

Areas

Increase/

Decrease Length of Season†

Groomed motorized route 2.1 0 December to April

Groomed motorized route, snowcoach 2.1 0 December to April

Groomed motorized trail 64.4 30.4 December to April

Plowed road 104 4 December to April

Ungroomed motorized trail or area 24 -11.6 December to April

Groomed nonmotorized 4 4 December to April

Ungroomed nonmotorized trail or area 28.4 2 December to April

Warming huts/interpretive centers 5 3 December to April

†Variable, dependent on snow conditions

Visitor Satisfaction and Experience

Opportunities to view wildlife and scenery. There would be increased opportunities to

view wildlife and scenery on routes other than plowed roads for both nonmotorized users

and oversnow vehicle users. Opportunities for views from plowed roads are the same as

alternative A.

Safety (the safe behavior of others). The placement of the CDST on a widened

highway shoulder would separate auto from snowmobile traffic and improve safety. The

co-location of motorized oversnow vehicles and nonmotorized users on the same

ungroomed trail corridor (Teton Park Road) would create additional problems, especially

with increased use.

Quality of the groomed surface. There would be an increased number of miles of

motorized groomed trails.

The availability of access to winter activities or experiences. There would be an

increased number of miles of motorized and nonmotorized groomed trails, as well as

additional support facilities. This would result in moderate to major beneficial

improvements for persons who wish to snowmobile and snowplane.

Availability of information. The availability of information would be improved by

adding new trails and warming hut facilities.

Quiet and Solitude. Opportunities for solitude and quiet forms of winter recreation

would be decreased. There would be a lack of separation between motorized and

nonmotorized trails throughout the park, which would affect skiers and snowshoers.
IMPACTS OF IMPLEMENTING ALTERNATIVE D

329

Clean air. This experiential value would be decreased from alternative A because of the

co-location of motorized and nonmotorized trails, and a lack of emphasis on “clean”

motorized technology. The availability of bio-based fuels and lubricants could mitigate

the impact.

Conclusion

There would be major beneficial changes for visitor experience for wildlife and scenery

viewing, assuming there would be no significant displacement of animals by humans.

There would be minor beneficial to minor adverse changes relating to safety due to

improvement of the CDST, while co-locating motorized and nonmotorized uses

elsewhere. The increased availability of information and trailside facilities would result

in moderate beneficial improvements to visitor experience. Opportunities to appreciate

clean air would be adversely affected. Increased visitor access and improved

developments under this alternative would result in a major adverse impact on

opportunities to experience quiet and solitude.

IMPACTS OF IMPLEMENTING ALTERNATIVE D

Effects on the Socioeconomic Environment

Alternative D contains several provisions for relatively minor changes in trail

management and grooming within YNP and GTNP. Most of these changes are unlikely

to significantly impact visitor decisions on whether to visit the parks for recreation. For

example, the impact on visitor expenditures from closing the Teton Park Road to

motorized use would be minor since other opportunities will be made available for

oversnow motorized travel. Two proposed management changes, however, have the

potential to significantly impact visitation levels to the GYA and, therefore, visitor

expenditures and the overall level of economic activity within the GYA. These are

proposals to close the road north of Colter Bay to wheeled-vehicles and open it to

snowmobiles, and to close the East Entrance access to YNP.

Regional Economy. The 1999 GYA winter visitor survey asked respondents how their

visitation would be affected if the road from Colter Bay to YNP’s South Entrance was

not plowed, and instead was open and groomed for snowmobiles and snowcoaches.

Based on analysis of the survey responses, GYA visitation by winter visitors who live

outside the five-county area would be reduced by 4.4% if the road from Colter Bay to

YNP’s South Entrance was not plowed, and instead was open and groomed for

snowmobiles and snowcoaches. Park visitors who reside outside of the five counties

made up 85.9% of total sampled visitors. This estimated reduction in visitation is a net

change that considers the responses of those current winter visitors who said they would

visit more often if the change occurred. Also considered in the calculation were those

respondents who said they would visit, but would shift their use to other areas of the

GYA (for example, from park lands to national forest lands).
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

330

In addition to anticipated winter visitation reductions resulting from the proposed

management change for the Colter to South Yellowstone road segment, it is assumed that

the visitors who currently use the East Entrance to YNP also would no longer do so. The

East Entrance to YNP is the least used winter entrance to the park. During the 1998-99

winter season, 2,955 visitors passed through the East Entrance. These visitors accounted

for about 2.5% of the total winter visitation to the park. While the 1999 GYA winter

visitor survey did not ask respondents how they would respond to such an East Entrance

closure, it can be assumed that a 2.5% reduction in park visitation would result. The

regional economic impacts of an East Entrance closure likely would be concentrated in

communities nearest the East Entrance to the park, primarily Cody, Wyoming.

Using the winter survey responses and the IMPLAN input/output model, it is estimated

that total economic output in the five-county area would be reduced by $1.3 million as a

result of the Colter to South Yellowstone road change, and winter closure of the East

Entrance to the park in alternative D. In addition it is estimated that 32 jobs within the

GYA would be lost due to reduced nonresident expenditures. This is a minor negative

impact in the context of the five-county economy.

Three-State Regional Economy. Overall, 65.5% of winter visitors in the GYA winter

visitor survey came from outside the three-state area of Montana, Idaho, and Wyoming.

Responses from this group of winter visitors indicate that there would likely be no

measurable change in winter trips to the region under the alternative D closure of the

Colter Bay to South Entrance road.

Minority and Low-Income Populations. It is not expected that the changes proposed

under alternative D would make the park more accessible to low-income visitors. The

closure of the road from Colter Bay to the South Entrance of YNP to wheeled-vehicles

has the potential to limit access by lower income groups. The impact is likely to be

negligible since the South Entrance itself is not a major destination.

Social Values. Most winter visitors support mechanized access to the parks. In the

context of overall park access, the changes proposed in alternative D are likely to result

in minor adverse impacts.

Nonmarket Values. Alternative D actions potentially would impact nonmarket values

of winter visitors by reducing the number of trips taken to the parks. The estimated

reduction in current winter user visitation resulting from the change in road management

from Colter Bay to YNP’s South Entrance and the closure of the East Entrance would

reduce total net economic value associated with visitor trips to the parks.

Based on the winter visitor survey, the nonmarket value of a trip to the parks of the GYA

is $91. It is estimated that park visitation would be reduced by 4.4% as a result of the

change in management of the road from Colter Bay to YNP’s South Entrance. Based on

current winter visitation levels, a 4.4% reduction in visitation would translate into a

$350,000 reduction in the aggregate nonmarket value of winter trips to the parks. In
IMPACTS OF IMPLEMENTING ALTERNATIVE D

331

addition a 2.5% reduction in winter trips associated with the closure of the East Entrance

to YNP would lead to a $200,000 reduction in the aggregate nonmarket value of winter

trips to the parks. The combined estimated loss in winter visitor net economic value is

$550,000. These are minor negative impacts in the context of overall trip benefits for

park visitors.

Conclusions

The alternative D management actions would have a negligible to minor impact on the

five-county and three-state economies through reduced visitation and nonresident visitor

expenditures. The alternative D actions would also have a minor negative impact on

current total trip nonmarket visitor benefits (through reduced visitation). The changes

proposed in alternative D are likely to result in minor adverse impacts on current visitors’

social values.

Effects on Air Quality and Public Health

In alternative D only 10% ethanol-blend fuels and bio-based lubricants would be sold in

the parks. By winter 2008-2009, only snowmachines that have been certified to meet

stricter emissions standards would be allowed in the parks. Oversnow vehicle emission

rates would be 40% of the baseline CO emission rate, 75% of the baseline PM10 rate, and

70% of the baseline hydrocarbon emission rate. Only bio-based lubricants and 10

percent ethanol fuel blends would be sold in the park.

Table 100, Table 101, and Table 102 summarize the results of CO modeling for six

locations in the three parks for alternative D. Table 100 and Table 101 show the

predicted maximum 1-hour average CO concentrations and the calculated maximum 8-

hour average CO concentrations, respectively. The percent contribution of each vehicle

type to the maximum CO concentrations also is provided in Table 102 for the six

locations. Table 103 and Table 104 provide corresponding model results for PM10 for the

same locations and conditions as CO.

Table 100. Maximum 1-hour average CO concentrations for alternative D.

Location

1-hr Maximum

Concentration (w/o

Background) (ppm)

1-hr Maximum

Concentration

(w/Background)

(ppm)

Change Relative to

Alternative A (w/o

Background) (%)

West Yellowstone Entrance 17.60 20.60 39.7

West Entrance to Madison Roadway 7.10 10.10 39.8

Old Faithful Staging Area 0.78 3.78 39.6

Flagg Ranch Staging Area 1.08 4.08 36.9

Flagg Ranch to Colter Bay Roadway 2.60 5.60 -136.4

Mammoth to NE Entrance Roadway 0.30 3.30 0

Table 101. Maximum 8-hour average CO concentrations for alternative D.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

332

Location

8-hr Maximum

Concentration (w/o

Background) (ppm)

8-hr Maximum

Concentration

(w/Background)

(ppm)

Change Relative to

Alternative A (w/o

Background) (%)

West Yellowstone Entrance 8.28†9.69†39.7

West Entrance to Madison Roadway 3.34†4.75†39.8

Old Faithful Staging Area 0.13 1.53 39.6

Flagg Ranch Staging Area 0.18 1.59 36.9

Flagg Ranch to Colter Bay Roadway 1.22†2.64†-136.4

Mammoth to NE Entrance Roadway 0.14†1.55†0

†Estimated from the modeled maximum 1-hour average concentration based on the persistence formula Ct2 = Ct1*(t1/t2)^0.365

(Cooper and Alley 1990).

Table 102. Vehicle contribution to CO concentrations for alternative D.

Contribution (%)

Location

SM SC AM LT HT TB SV

West Yellowstone Entrance 97.2 2.6 0 0 0.2 0 0

West Entrance to Madison Roadway 98.1 1.9 0 0 0.1 0 0

Old Faithful Staging Area 97.5 2.5 0 0 0.1 0 0

Flagg Ranch Staging Area 97.3 2.6 0 0 0.1 0 0

Flagg Ranch to Colter Bay Roadway 98.0 1.9 0 0 0.1 0 0

Mammoth to NE Entrance Roadway 0 0 26.5 66.9 0.5 0 6.1

SM=snowmobile, SC=snowcoach, AM=automobile, LT=light truck, HT=heavy truck, TB=tour bus, SV=shuttle van.

Table 103. Maximum 24-hour average PM10 concentrations for alternative D.

Location

24-hr Maximum

Concentration

(w/o Background)

(μg/m3)

24-hr Maximum

Concentration (w/

Background)

(μg/m3)

Change Relative

to Alternative A

(w/o Background)

(%)

West Yellowstone Entrance 11.69†34.69 74.1

West Entrance to Madison Roadway 2.84†25.84 73.5

Old Faithful Staging Area 0.16 5.16 75.1

Flagg Ranch Staging Area 0.22 5.22 64.6

Flagg Ranch to Colter Bay Roadway 0.95†5.95 0

Mammoth to NE Entrance Roadway 0.32†5.32 0

†

 Estimated from the modeled maximum 1-hour average concentration based on the persistence formula Ct2 = Ct1*(t1/t2)^0.365

(Cooper and Alley 1990).
IMPACTS OF IMPLEMENTING ALTERNATIVE D

333

Table 104. Vehicle contribution to PM10 concentrations for alternative D.

Contribution (%)

Location SM SC AM LT HT TB SV

West Yellowstone Entrance 97.3 0.8 0 0 1.8 0 0

West Entrance to Madison Roadway 91.1 4.1 0 0 4.7 0 0

Old Faithful Staging Area 99.3 0 0 0 0.7 0 0

Flagg Ranch Staging Area 98.9 0 0 0 1.1 0 0

Flagg Ranch to Colter Bay Roadway 90.7 4.3 0 0 5.0 0 0

Mammoth to NE Entrance Roadway 0 0 22.5 46.6 26.7 0 4.2

SM = snowmobile, SC = snowcoach, AM = automobile, LT = light truck, HT = heavy truck, TB = tour bus, SV = shuttle van.

Visibility

The visibility assessment indicates that under this alternative, vehicular emissions would

cause localized, perceptible, visibility impairment near the West Entrance and in the area

around Old Faithful and Flagg Ranch. The emissions along roadway segments would not

lead to perceptible visibility impairment.

Conclusion

As noted in Table 100, Table 101, and Table 103, the model predicts moderate and major

beneficial impacts on CO and PM10 levels, respectively, relative to alternative A at the

West Entrance, along the West Entrance to Madison roadway, and at the two staging

areas. However, these major and moderate beneficial impacts would not be realized until

winter 2008-2009 winter, except for minor benefits attributable to bio-based lubricants

and ethanol fuel blends. A major adverse impact on CO concentration is predicted along

the Flagg Ranch to Colter Bay roadway. This increase in CO concentration is

attributable to large assumed increases in snowmobiles using this roadway; for PM10, a

major beneficial impact would be realized.

Effects on Public Safety

Closing the YNP East Entrance would eliminate all risks associated with avalanches and

future avalanche control on Sylvan Pass to employees and the 3% of snowmachine riders

who use the East Entrance each winter. More frequent grooming of the route from West

Yellowstone to Old Faithful would reduce the potential for accidents that result from

poor road conditions. The geographic separation of uses by area under this alternative

would reduce user conflict along the roadways that provide access to different types of

activities.

In GTNP and the Parkway, the development of additional ski and snowshoe trails would

increase nonmotorized recreation opportunities and decrease the potential for conflicts

between different types of users. Closing the road between Colter Bay and Flagg Ranch

to wheeled-vehicles and allowing snowmobile use on this segment would eliminate the

potential for inter-modal conflict along this stretch of the CDST. It would eliminate a
CHAPTER IV

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major source of winter vehicle accidents, vehicle-wildlife accidents and unsafe vehicular

activity. Limiting oversnow vehicle use of Jackson Lake to snowplanes would similarly

eradicate the current low potential for inter-modal conflicts on the lake. Eliminating

snowmobile use of ungroomed trails would improve safety.

Conclusion

Implementation of this alternative would result in moderate beneficial short-term

improvements to public safety in the three park units due to the introduction of several

positive safety measures. This assumes that no additional safety risks are associated with

this alternative. Impacts would affect employees and visitors.

Effects on Geothermal Features

The effect of this alternative on YNP geothermal features would be the same as described

in alternative B, except for local impacts associated with Fountain Flats and Mammoth.

Grooming the Fountain Flats road for motorized use may increase the quantity of adverse

impacts on geothermal resources found along this road. There may be more off-road

snowmobiling in this area, which may lead to moderate long-term impacts on geothermal

features. Similar impacts may occur on this area as those described under the groomed

road segments of alternative A.

The effects of unrestricted backcountry use in the Mammoth area would have the same

effects as alternative A.

Conclusion

Overall, there would be more benefits under this alternative as compared to alternative A,

since there will be no new winter support facilities near geothermal areas. Minor adverse

impacts may continue on geothermal features located along groomed roads, with minor

effects on features along the Fountain Flats road and near Mammoth.

Effects on Water and Aquatic Resources

Potential pollution sources are the same as alternative A. The potential impacts along

“high” risk road segments are the same as alternative A. The exception is a decrease in

risk on the Canyon Village to Fishing Bridge “high” risk segment as the projected

number of snowmobiles on that segment decreases.

The elimination of all vehicles would decrease the risk of water pollution along the

“medium” risk Fishing Bridge to East Entrance road segment.

Increased snowmobile usage would increase the risk of water pollution along the “low”

risk Flagg Ranch to Colter Bay segment. On the Teton Park Road with the elimination of

all vehicles and on the Moose-Wilson Road with the prohibition of snowmobiles the risk

of water pollution would decrease.
IMPACTS OF IMPLEMENTING ALTERNATIVE D

335

Table 10539. Snowmachines and associated risk levels for alternative D.

Impact: Daily Vehicle

Miles Traveled Along

the Segment in Alt.

A*

Impact: Daily Vehicle

Miles Traveled Along

the Segment in Alt.

D*

Road Segment

Risk ±

Rating SM SC SM SC

Mammoth to Norris Medium 641 69 641 69

West Entrance to Madison Medium 7759 127 7759 127

Madison to Norris High 3458 73 3458 73

Norris to Canyon Village Low 2214 47 2214 47

Canyon Village to Fishing Bridge High 2370 50 148 3

Fishing Bridge to East Entrance Medium 983 0 0 0

Fishing Bridge to West Thumb Medium 2627 55 2627 55

Madison to Old Faithful High 7818 165 7840 160

Old Faithful to West Thumb Medium 3560 73 3560 73

West Thumb to Flagg Ranch Medium 4219 103 4219 103

Grassy Lake Road High 184 0 200 0

Flagg Ranch to Colter Bay Low 379 0 2816 64

Colter Bay to Moran Junction High 248 0 250 0

Moran Junction to East Entrance Medium 49 0 50 0

Teton Park Road Low 156 0 0 0

Moose-Wilson Road Low 6 0 0 0

Conclusion

Two stroke engines would continue to deposit pollutants into snowpack along groomed

park roads in YNP and GTNP. The effect of this deposition on water quality is

undetermined, but there is currently no evidence of measurable changes in water quality

or effects on aquatic resources. It is possible that accumulations of pollutants in aquatic

systems may have adverse impacts on wetlands and aquatic resources downstream from

high risk road segments. Oversnow vehicle use in this alternative would involve

localized high risk to surface water quality, but reduced oversnow vehicle-miles traveled

along high risk road segments in the three park units by about 14%. Discontinuing

snowmobile use on Jackson Lake would reduce pollution sources by half into Jackson

Lake. Minor to moderate long-term adverse impacts to water resources throughout

GTNP and the Parkway could occur related to the increased number of winter use

opportunities. Minor short-term water quality and wetland impacts could occur in

streams along the eastern side of US 89/287 as a result of CDST construction.

 

39 *SM = Snowmobile, SC = Snowcoach The source of pollutants is emissions from snowmobiles, which

produce (conservatively) 10 times as many emissions per mile as most wheeled vehicles. Single

snowcoaches produce fewer emissions then single snowmobiles.

±High = within 100 meters of aquatic system on 76% to 100% of the road segment; Medium = within 100

meters on 51% to 75% of the road segment; Low risk segments are within 100 meters of rivers less than 50%.
CHAPTER IV

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Mitigation

The portions of the CDST that would deviate from the road shoulder would be designed

and sited to minimize impacts on all park resources including wildlife, vegetation, and

wetlands. Focused water monitoring programs should be designed and implemented to

determine whether there are specific aquatic resource effects from winter recreational

use. The use of bio-based fuels by NPS and the availability of fuels in gateway

communities may result in a minor decrease in pollutant deposition into snow. Best

management practices would be used during the construction, reconstruction, or winter

plowing of trails and roads to prevent unnecessary vegetation removal, erosion, and

sedimentation. The release of snowpack contaminants into surface water could be

mitigated by disconnecting snowmelt drainages from trails used by snowmobiles. Any

new or reconstructed winter use sanitary facilities would be constructed in locations and

use advanced technologies to protect water resources. A focused program of monitoring

would reduce the uncertainty of impacts from oversnow vehicles, and if necessary,

indicate best management practices.

Effects on Wildlife

Ungulates

Effects of groomed roads and trails. Packed trails may influence wildlife movements

and distributions by facilitating travel into areas that would normally be inaccessible due

to deep snow. Under alternative D YNP would groom about 217 miles, about 4 miles

less than under current management. GTNP and the Parkway would groom about 36

miles, the same as current management.

In YNP closure of the East Entrance road may affect bison movements from the Pelican

Valley wintering area to the Mary Mountain wintering area, and movements outside the

park’s east boundary. The level of effect depends on winter snow conditions and how

bison maintain traditional travel routes without groomed road surfaces. In the parks as a

whole, the effects are the same as those under alternative A.

Effects of motorized oversnow use of groomed and ungroomed roads and trails. The

use of motorized oversnow vehicles can cause injury and death to wildlife, especially in

poor lighting conditions and during snowfall, and can cause displacement from preferred

habitats.

From 1989 to 1998 only one large mammal was killed by a snowmobile between Fishing

Bridge and the East Entrance (Gunther et al. 1998). Collisions would decrease under

alternative D because the East Entrance road in YNP would be closed, and snowmobiles

would be eliminated from the 21-mile segment of GTNP Teton Park Road and from 11

miles of the Antelope Flats area, and late night motorized travel would be prohibited.

Overall, displacement resulting from these actions would be slightly lower than in

alternative A for YNP and lower than in alternative B for GTNP.
IMPACTS OF IMPLEMENTING ALTERNATIVE D

337

Effects of plowed roads. Road plowing may cause habitat fragmentation by creating

structural barriers (i.e., snow berms) to ungulate movements (Aune 1981). In addition

plowed roads, like groomed roads, may also provide an energy efficient mechanism for

wildlife movements, including bison, elk, and moose. Under alternative D YNP would

plow 76 miles of road for wheeled-vehicle access in the winter, the same as now. GTNP

and the Parkway would plow 83 miles, a decrease of 17 miles from current management.

Effects of plowed roads would be essentially the same as alternative A for YNP, and

would decrease from alternative A in GTNP.

Effects of motorized use of plowed roads. The effects of plowed roads are similar to

those of groomed roads, except that the magnitude of the effect is usually greater. The

use of motorized vehicles on plowed roads can cause displacement from preferred

habitats and injury and death to wildlife, especially in poor lighting conditions, at dusk

and dawn, and during snowfall.

Effects of plowed roads would be essentially the same as alternative A for YNP, and

would decrease from alternative A in GTNP.

Effects of nonmotorized use of groomed and designated ungroomed routes. The

primary effects of nonmotorized use on ungulates are displacement from preferred

habitats, especially geothermal areas that are important for winter survival in YNP, and

increased energy expenditures, including physiological stress, which may reduce

individuals’ chances of survival. Under alternative D these opportunities increase in

YNP from 37 miles to 43 miles of groomed nonmotorized routes, and increase from 26

miles to 37 miles of ungroomed routes GTNP and the Parkway. Increasing these

opportunities increases the potential for adverse impacts associated with them. However,

the potential for impact is relatively low since most trails and routes are located in areas

not presently used or preferred by ungulates. The exception to this would be short trail

segments in YNP near and through geothermal areas, such as at Mammoth Hot Springs.

For all parks the level of impact is similar to alternative A.

Effects of unregulated backcountry nonmotorized use. Unregulated backcountry

nonmotorized use is more random and infrequent relative to nonmotorized use on

designated routes. Consequently, although encounters between backcountry users and

ungulates may only occur sporadically, they can be especially disturbing and lead to

additional energy expenditure and stress that reduces animals’ chances of survival and

reproduction. This alternative mitigates potential effects associated with these activities

in YNP by eliminating unregulated backcountry use in winter range. Use would be

limited to designated routes, and routes would only be designated in areas where ungulate

needs are not of concern.

Impacts from this use in GTNP likely would increase relative to alternative A. Increased

cross-country skiing and snowshoeing use would be anticipated along the Teton Park
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

338

Road, in backcountry areas west of the road, and throughout Antelope Flats because of

the elimination of snowmobiles. This increased use could adversely impact ungulates

and their movement, and may result in higher energy expenditures as they attempt to

move away or avoid such use. Moderate to major adverse impacts on bighorn sheep

would continue, as well as potential impacts on moose, elk, and bison on Blacktail Butte

and Wolff Ridge.

Effects of the presence and use of winter support facilities. Increases in human

activity associated with the presence of support facilities may displace species sensitive

to human disturbance. This alternative proposes to add warming hut facilities at Jenny

Lake.

Overall effects would be the same as alternative A because Jenny Lake is not considered

ungulate winter range.

Federally Protected Species

Effects of groomed roads and trails. Packed trails may influence wildlife movements

and distributions by facilitating travel into areas that would normally be inaccessible due

to deep snow. Under alternative D YNP would groom about 217 miles of road surface,

about 4 miles less than under current management. GTNP and the Parkway would

groom about 36 miles, the same as current management.

Impacts are generally as stated in alternative A. If federally protected species activity is

known to occur in an area, park managers can close the area to human activity to prevent

disturbance.

Effects of motorized use of groomed and ungroomed roads and trails. The use of

motorized oversnow vehicles can cause displacement from preferred habitats. No

collisions have occurred between oversnow motorized vehicles and federally protected

species in the parks.

Closure of the East Entrance road, and elimination of 25 miles of snowmobile route

would eliminate fragmentation over the entire eastern portion of YNP, allowing free

movement for species that are active in the winter. Bald eagle use along the north shore

of Yellowstone Lake would be undisturbed as well.

In GTNP the types of impacts for alternative D would be similar to alternatives A and B.

However, snowmobiling would be eliminated in all parts of the park except along the

CDST and on Grassy Lake Road west of Flagg Ranch. Any potential adverse effects

associated with motorized oversnow use would decrease because of decreased

opportunities. Where snowmobiling now occurs in the Antelope Flats area and along the

Moose-Wilson Road southwest of Moose Junction, cross-country skiing and

snowshoeing would occur. Snowmobiles would not be allowed on Jackson Lake.

Current snowmobile use is low because snowmobiles tend to bog down in the snow on

the lake; however, snowplanes are and would continue to be the predominant use.
IMPACTS OF IMPLEMENTING ALTERNATIVE D

339

Disturbance caused by snowplanes on the frozen surface of Jackson Lake would continue

to cause only negligible impacts on eagles because foraging and nesting activities would

be minimal before the breakup of the ice. In all park units, if monitoring indicates

disturbance to bald eagles, additional closures may be enacted. Effects on federally

protected species would remain at the level of negligible to minor.

Effects of plowed roads. Road plowing may cause habitat fragmentation by creating

structural barriers (i.e., snow berms) to wildlife movements (Aune 1981). In addition

similar to groomed roads, plowed roads may influence wildlife movements and

distributions by facilitating travel for wildlife into areas that would normally be

inaccessible due to deep snow. Under alternative D YNP would plow 76 miles of road

for wheeled-vehicle access in the winter. GTNP and the Parkway would plow 83 miles,

a decrease of 17 miles from current management.

Impacts are generally as stated in alternative A. If federally protected species activity is

known to occur in an area, park managers can close the area to human activity to prevent

disturbance.

Effects of motorized use of plowed roads. The effects of traffic on plowed roads are

similar to those of traffic on groomed roads, except that the magnitude of the effect is

usually greater. The use of motorized vehicles on plowed roads can cause displacement

from preferred habitats and injury and death to wildlife, especially in poor lighting

conditions, at dusk and dawn, and during snowfall.

Impacts are generally as stated in alternative A — none to minor. If federally protected

species activity is known to occur in an area, park managers can close the area to human

activity to prevent disturbance.

Effects of nonmotorized use on groomed and designated ungroomed routes. The

primary effects of nonmotorized use on wildlife are displacement from preferred habitats

and increased energy expenditures, including physiological stress, which may reduce

individuals’ chances of survival. Under alternative D these opportunities increase in

YNP from 37 miles to 43 miles of groomed nonmotorized routes, and increase from 26

miles to 37 miles of ungroomed routes in GTNP and the Parkway.

Potential impacts are generally as stated in alternative A — none to negligible. If

federally protected species activity is known to occur in an area, park managers can close

the area to human activity to prevent disturbance.

Effects of unregulated backcountry nonmotorized use. Unregulated backcountry

nonmotorized use is more random and infrequent relative to nonmotorized use on

designated routes. Consequently, although encounters between backcountry users and

federally protected wildlife species may only occur sporadically, they may cause

displacement and additional energy expenditure and stress that reduces animals’ chances

of survival and reproduction. This alternative mitigates potential effects associated with
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ENVIRONMENTAL CONSEQUENCES

340

these activities in YNP by eliminating unregulated backcountry use in winter range. Use

would be limited to designated routes.

Effects associated with backcountry use would decrease from alternative A in YNP and

in GTNP and the Parkway. Impacts are generally as stated in alternative A.

Presence and use of winter support facilities. Warming huts and campgrounds can

cause habituation in some wildlife species to the presence of human food and garbage,

and lead to human-wildlife conflicts. In addition increases in human activity associated

with the presence of support facilities may displace species sensitive to human

disturbance. This alternative proposes to add warming hut facilities at Jenny Lake.

Impacts are generally as stated in alternative A — negligible to minor. If federally

protected species activity is known to occur in an area, park managers can close the area

to human activity to prevent disturbance. Impacts to bears associated with habituation to

human developments and food are negligible. Under all alternatives winter wildlifeproof garbage facilities will be constructed.

Species of Special Concern

Effects of groomed roads and trails. Packed trails may influence wildlife movements

and distributions by facilitating travel into areas that would normally be inaccessible due

to deep snow, inhibiting foraging activities of carnivores that tunnel beneath the snow to

hunt subnivian prey, and reducing subnivian prey availability by increasing mortality of

these small mammals. Under alternative D YNP would groom about 217 miles of road

surface, about 4 miles less than under current management. GTNP and the Parkway

would groom about 36 miles, the same as current management.

Impacts are generally as stated in alternative A — none to minor.

Effects of motorized oversnow use of groomed and ungroomed roads and trails. The

most likely impacts to species of special concern are displacement from preferred

habitats, and degradation of the aquatic environment from pollutants in the snowpack.

Documented mortality caused by collisions with oversnow vehicles in the parks is rare.

In 10 years only one of these species (a marten) was reportedly killed by a snowmobile in

YNP (Gunther et al. 1998).

Impacts are generally as stated in alternative A — none to minor. If species activity is

known to occur in an area, park managers can close the area to human activity to prevent

disturbance. For YNP closure of the East Entrance road and elimination of 25 miles of

snowmobile route would eliminate fragmentation and displacement over the entire

eastern portion of YNP, allowing free movement for species that are active in the winter

such as wolverines and fishers. Closure of the road will also eliminate the need for

avalanche control, thus removing any potential adverse effects to wolverines. Trumpeter

swan use along the north shore of Yellowstone Lake would be undisturbed as well.
IMPACTS OF IMPLEMENTING ALTERNATIVE D

341

See Water and Aquatic Resources, Chapter IV for an assessment of the impacts of

exhaust on water quality in the parks.

Effects of plowed roads. Similar to groomed roads, plowed roads also provide an

energy efficient mechanism for wildlife movements. Under alternative D YNP would

plow 76 miles of road for wheeled-vehicle access in the winter, a decrease of 20 miles

over current management. GTNP and the Parkway would plow 83 miles, a decrease of

17 miles from current management.

Impacts are generally as stated in alternative A. If species activity is known to occur in

an area, park managers can close the area to human activity to prevent disturbance.

Effects of motorized use of plowed roads. The most likely impact to species of special

concern is displacement from preferred habitats and mortality caused by collisions with

wheeled-vehicles.

Impacts are generally as stated in alternative A — none to negligible. If species activity

is known to occur in an area, park managers can close the area to human activity to

prevent disturbance.

Effects of nonmotorized use on groomed and ungroomed designated routes. The

primary effects of nonmotorized use are displacement from preferred habitats, and

increased energy expenditures, including physiological stress, which may reduce

individuals’ chances of survival. Under alternative D, YNP increases these opportunities

from 37 miles to 43 miles of groomed nonmotorized routes, and GTNP and the Parkway

increase from 26 miles to 37 miles of ungroomed routes.

Impacts are as stated generally in alternative A — none to minor. Groomed trails are not

in known swan habitat; therefore, no effects on swans would occur.

Unregulated backcountry nonmotorized use. Unregulated backcountry nonmotorized

use is more random and infrequent relative to nonmotorized use on designated routes.

Although encounters between backcountry users and species of special management

concern may occur sporadically, they can be especially disturbing and lead to additional

energy expenditure and stress that reduces animals’ chances of survival and reproduction.

This alternative mitigates potential effects associated with these activities in YNP by

eliminating unregulated backcountry use in winter range. Use would be limited to

designated routes where wildlife concerns are minimal.

Effects associated with backcountry use would decrease from alternative A in YNP, and

in GTNP and the Parkway, impacts are generally as stated in alternative A.

Presence and use of winter support facilities. The primary effects of warming huts and

campgrounds on species of special concern are associated with increases in human

activity and the subsequent disturbance and displacement of species or their prey. This

alternative proposes to add warming hut facilities at Jenny Lake.
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ENVIRONMENTAL CONSEQUENCES

342

Specifically, huts located in thermally influenced ungulate winter range could displace

ungulates, and thus affect bison and elk carcass availability for wolverines, fishers, and

marten. Because the huts at Jenny Lake would not be located in ungulate winter range,

they would not affect the availability of carrion for these species. Therefore, impacts to

other species of special concern would be the same as those under alternative A.

Conclusion

Overall effects of this alternative are similar to alternative A. Reductions in oversnow

travel opportunities benefit ungulates by eliminating use on the east side of YNP, and

restricting oversnow travel in GTNP to groomed routes in the northern part of the park.

Elimination of access from the East Entrance to Fishing Bridge eliminates other effects

associated with groomed routes, including fragmentation, and displacement. Restricted

backcountry travel in YNP reduces effects associated with off-trail travel. Nonmotorized

opportunities would be increased and may affect ungulates in GTNP. Increased

interpretive opportunities and augmented enforcement capabilities would mitigate any

other impacts.

Although impacts to populations resulting from winter recreation are neither long term

nor significant, impacts to individual members of the population can be important,

leading to death either directly from collisions or continued harassment, or indirectly

through management actions taken as a response to habituation to human presence and

food. Although concerned about impacts to individuals, the NPS primarily provides for

the protection of native animal populations from management actions (with the exception

of federally protected species). For example, see Chapter II, NPS 77, Natural Resources

Management.

Ungulates

• Effects of groomed roads and trails on animal movements — unknown if and to what

extent beneficial effects outweigh negative effects. Any effects would decrease from

alternative A in YNP because the East Entrance road would be closed. Otherwise same as

alternative A.

• Effects of motorized oversnow use of groomed and ungroomed roads and trails on: 1)

mortality caused by collisions – adverse, negligible, and short term, and 2) displacement

from preferred habitats – adverse, minor to moderate, and short term. Impacts would

decrease over current management due to restrictions on late night travel, the closure of the

East Entrance road in YNP, and the elimination of some motorized oversnow routes in

GTNP.

• Effects of plowed roads on: 1) habitat fragmentation – adverse, minor, and short term; and

2) animal movements – unknown if and to what extent beneficial effects outweigh negative

effects. Effects would be the same as alternative A for YNP and less than alternative A for

GTNP.

• Effects of motorized use of plowed roads on: 1) mortality caused by collisions – adverse,

minor, and short term; and 2) displacement from preferred habitats – adverse, moderate,

and long term. Effects would be the same as alternative A for YNP and less than

alternative A for GTNP.

• Effects of nonmotorized use of groomed and designated ungroomed routes on displacement

from preferred habitats – adverse, minor, and short term. Same as alternative A for all

parks.
IMPACTS OF IMPLEMENTING ALTERNATIVE D

343

• Effects of unregulated backcountry nonmotorized use on displacement from preferred

habitats – adverse, negligible to minor, and short term in YNP (a decrease from alternative

A due to the elimination of unregulated backcountry use), and adverse, minor, and short

term in GTNP (an increase over alternative A). Impacts on bighorn sheep in GTNP would

remain moderate to major and long term if no mitigation is applied.

• Effects of the presence and use of winter support facilities on displacement – adverse,

minor, and short term. Same as alternative A.

Federally Protected Species

• Effects of groomed roads and trails on animal movements: 1) bald eagles, grizzly bears,

and wolves — no effect; and 2) lynx – adverse, negligible to major, and short term,

depending upon lynx distribution and abundance in the parks. Same as alternative A.

• Effects of motorized oversnow use of groomed and ungroomed roads and trails on

displacement from preferred habitats – adverse, negligible, and short term for all species

excluding the grizzly bear, which will not be active during the winter use season. Slight

decrease in impact over alternative A, especially for YNP.

• Effects of plowed roads on: 1) habitat fragmentation – no effect on any of the listed

species; and 2) animal movements – no known effect on any of the listed species. Same as

alternative A.

• Effects of motorized use of plowed roads on: 1) mortality caused by collisions – adverse,

negligible, and short term on bald eagles and grizzly bears; adverse, minor, and short term

on wolves; no known effect to date on lynx; and 2) displacement from preferred habitats –

adverse, negligible, and short term on bald eagles, no effect on grizzly bears; no known

effect to date on wolves and lynx. Same as alternative A.

• Effects of nonmotorized use of groomed and designated ungroomed routes on displacement

from preferred habitats – adverse, negligible, and short term on bald eagles; no effect on

grizzly bears; no known effect to date on wolves and lynx. Same as alternative A.

• Effects of unregulated backcountry nonmotorized use on displacement from preferred

habitats – adverse, minor, and short term on bald eagles; adverse, negligible, and short term

on grizzly bears; adverse, minor, and short term on wolves; no known effect to date on

lynx. In YNP effects would decrease over alternative A because of the elimination of

unregulated backcountry use; in GTNP impacts would remain the same as alternative A.

• Effects of the presence and use of winter support facilities on displacement – no affect on

bald eagles; adverse, negligible, and short term on grizzly bears, with mitigation; adverse,

minor, and short term on wolves; lynx – adverse, negligible to major, and short term, (huts

in the Jenny Lake area are in potential Canada lynx habitat). Other than lynx, effects are

generally the same as alternative A.

Species of Special Concern

• Effects of groomed roads and trails on: 1) animal movements – no known effect on

wolverines; adverse, negligible, and short term on fishers and martens; no effect on otters,

swans, reptiles, amphibians, and fish; 2) foraging activities – adverse, negligible, and short

term on marten; no effect on the other species; and 3) subnivian prey availability —

adverse, negligible, and short term on marten, no effect on the other species. Same as

alternative A.

• Effects of motorized oversnow use of groomed and ungroomed roads and trails on

displacement – no known effect on wolverine; adverse, negligible, and short term on

fishers and marten; no effect on otters, reptiles, amphibians, and fish; adverse, minor, and

short term on swans. Generally the same as alternative A. The closure of the East

Entrance road eliminates the need for avalanche control, which may benefit wolverines.

• Effects of plowed roads on animal movements – no known effect on wolverines, fishers,

and martens; no effect on otters, swans, reptiles, amphibians, and fish. Same as alternative

A.

• Effects of motorized use of plowed roads on displacement from preferred habitats – 1)

adverse, negligible, and short term on wolverines, fishers, and martens; no effect on otters,
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ENVIRONMENTAL CONSEQUENCES

344

swans, reptiles, amphibians, and fish; and 2) mortality from collisions — adverse,

negligible, short term on otters and martens; no effect to date on other species. Same as

alternative A.

• Effects of nonmotorized use of groomed and designated ungroomed routes on displacement

from preferred habitats – no effect (wolverines); no known effect (fishers, martens, and

otters); adverse, minor, and short term (swans); adverse, negligible, short term (sagebrush

lizard) no effect (rubber boa, amphibians, and fish). Same as alternative A.

• Effects of unregulated backcountry nonmotorized use on displacement from preferred

habitats – adverse, negligible, and short term on wolverines and sagebrush lizard; no

known effect on fishers, martens, and otters; adverse, minor, and short term on swans; no

effect on rubber boa, amphibians, and fish. Effects would decrease from alternative A in

YNP, and would remain the same in GTNP.

• Effects of the presence and use of winter support facilities on displacement of potential

prey (carcass) availability – adverse, minor, and short term on wolverines, fishers, and

martens; no effect on swans, rubber boa, amphibians, and fish; no known effect on otters;

adverse, minor, and short term on (sagebrush lizard). Same as alternative A.

Mitigation

• Backcountry monitoring and administration should be implemented in GTNP. Additional

area closures could be imposed if monitoring indicates such a closure is warranted for the

protection of wintering bighorn sheep and moose.

• Creating wildlife escape routes along winter roads may mitigate some of the impacts due to

groomed road surfaces.

• Use of groomed and plowed surfaces by bison and other ungulates would continue to be

monitored.

• Snow track surveys for carnivores, including lynx, on both groomed and ungroomed routes

would be conducted.

Effects on Natural Soundscape

Audibility analysis — combined effects of all wheeled and oversnow vehicles

Table 106 presents the acres of park land by road segment where any wheeled or

oversnow vehicle noise would be audible under the two background conditions,

“average” and “quiet,” as defined in the Assumptions and Methodologies section of this

chapter. For each background condition, acreage is presented for three categories of

audibility: 1) audible for any amount of time (labeled “audible at all”); 2) audible for

10% of the time or more; and 3) audible for 50% of the time or more. Appendix M

contains tables with distances to audibility for each segment for each alternative.

Alternative D features no oversnow vehicles on the road segment from Fishing Bridge to

the YNP East Entrance. It eliminates snowmobiles from Teton Park Road and Jackson

Lake, and eliminates wheeled-vehicles from Colter Bay to Flagg Ranch. It includes the

“clean and quiet” snowmobile and snowcoach requirements based on a 60 dBA noise

emission level at 50 feet (compared to 70 dBA for alternative B). It requires that all

snowplanes on Jackson Lake meet the current limit of 86 dBA at 50 feet.

The results for alternative D show that for the “average” background condition, wheeled

or oversnow vehicles would be audible to some degree for over 110,000 acres in the three

park units. For over 52,000 of those acres, wheeled or oversnow vehicles would be
IMPACTS OF IMPLEMENTING ALTERNATIVE D

345

audible for at least 10% the time during the day. For over 13,000 of those acres, they

would be audible for at least half of the time during the day. These acreage totals

increase by 8%, 19%, and 11% for the “quiet” background conditions for the three

audibility categories, respectively.

The 60-dB “clean and quiet” requirement results in major reductions in audibility acreage

over all segments that carry oversnow vehicles. These reductions are less evident when

looking at the totals because of large contribution from wheeled-vehicle use on the

segment from Moran Junction to the South Entrance of GTNP for all three audibility

categories. This contribution is almost constant for all of the alternatives. For example,

over 80% of the acreage for the “audible 50% or more” categories is along this segment.

The plowed road from Mammoth to the YNP Northeast Entrance is a major contributor

to the “audible at all” acreage (and to a lesser extent “audible 10% or more”), which

remains virtually unchanged across all alternatives.

The other key segments for the “audible 50% or more” categories are from the YNP

West Entrance to Madison; from Madison to Old Faithful; and from Moran Junction to

GTNP’s East Entrance. However, the acreage amounts are significantly lower than for

the no action alternative. The acreage along the segments from West Entrance to Old

Faithful is higher than for alternative B because of the use of wheeled-vehicles only for

alternative B.

Snowplanes on Jackson Lake are also major contributors to the “audible at all”

categories, although the acreage is greatly reduced over the no action alternative because

of the sound level restriction.

The audibility acreage is reduced to zero for Teton Park Road, but is only slightly

reduced along the Flagg Ranch-Colter Bay segment.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

346

Table 106. Acres of park land affected by vehicle audibility for alternative D.

With Average Background

Conditions

With Quiet Background

Conditions

Road Segment (Miles)

Audible

at All

Audible

10% of the

Time or

More

Audible

50% of the

Time or

More

Audible

at All

Audible

10% of

the Time

or More

Audible

50% of

the Time

or More

1. Mammoth to Northeast Entrance 47 16,126 5,445 0 16,822 6,342 0

2. Mammoth to Norris 21 6,302 0 0 6,733 0 0

3. West Entrance to Madison 14 4,598 3,290 1,493 5,040 3,811 2,006

4. Madison to Norris 14 4,103 2,647 0 4,447 3,128 0

5. Norris to Canyon Village 12 3,419 1,437 0 3,719 1,905 0

6. Canyon Village to Fishing Bridge 16 5,181 2,558 0 5,568 3,033 0

7. Fishing Bridge to East Entrance 27 No Veh. No Veh. No Veh. No Veh. No Veh. No Veh.

8. Fishing Bridge to West Thumb 21 7,454 4,186 0 7,931 4,731 0

9. Madison to Old Faithful 16 5,211 3,576 305 5,719 4,182 563

10. Old Faithful to West Thumb 17 4,844 2,796 0 5,268 3,322 0

11. West Thumb to Flagg Ranch 24 7,263 3,089 0 7,839 3,923 0

12. Grassy Lake Road 7.6 1,649 0 0 1,860 0 0

13. Flagg Ranch to Colter Bay 15.6 5,450 3,018 0 5,784 3,490 0

14. Colter Bay to Moran Junction 10.2 4,582 2,236 0 4,929 2,431 0

15. Moran Junction to East Entrance 2 1,193 707 474 1,294 774 517

16. Moran Junction to South Entrance 26 21,714 14,462 11,120 23,842 16,827 11,823

17. Teton Park Road 15 No Veh. No Veh. No Veh. No Veh. No Veh. No Veh.

18. Moose-Wilson Road 2.5 672 0 0 708 0 0

19. Antelope Flats Snowmobile Route -- No Veh. No Veh. No Veh. No Veh. No Veh. No Veh.

20. Jackson Lake 9.7 10,963 3,326 0 12,280 4,905 0

TOTAL 110,723 52,772 13,392 119,781 62,803 14,910

Average sound level analysis

To give a sense of the effect of the number of oversnow or wheeled-vehicles on a road

segment, and their speed and sound level, Table 107 shows the computed hourly

equivalent or “average” sound level (Leq) over the daytime period. Levels are shown for

each road segment at two distances, 100 feet and 4,000 feet, and for both open and

forested terrain. These hourly Leq values do not have the background sound level added

in to them. Also they cannot be compared against the background levels to assess

audibility, since Leq represents a long-term average of both quiet and loud moments.

The hourly Leq values at 100 feet are highest for Jackson Lake and from Moran Junction

to the South Entrance of GTNP. These segments also have the highest Leq at a distance

of 4,000 feet away. However, all segments with oversnow vehicles other than Jackson

Lake have a major 12 dB to 13 dB reduction in the hourly Leq compared to the no action
IMPACTS OF IMPLEMENTING ALTERNATIVE D

347

alternative. This is due to the 60 dBA limit on the snowmobile and snowcoach noise

emission levels.

Table 107. Average hourly Leq from wheeled and oversnow vehicle noise at two

distances to each road segment for alternative D.

Leq at Distance (dBA)

Open Terrain Forested Terrain

Road Segment 100 feet 4,000 feet 100 feet 4,000 feet

1. Mammoth to Northeast Entrance 35 2 33 0

2. Mammoth to Norris 31 0 29 0

3. West Entrance to Madison 43 9 42 1

4. Madison to Norris 39 6 38 0

5. Norris to Canyon Village 38 4 37 0

6. Canyon Village to Fishing Bridge 37 3 36 0

7. Fishing Bridge to East Entrance No Veh. No Veh. No Veh. No Veh.

8. Fishing Bridge to West Thumb 37 3 35 0

9. Madison to Old Faithful 42 9 41 1

10. Old Faithful to West Thumb 39 5 37 0

11. West Thumb to Flagg Ranch 38 4 37 0

12. Grassy Lake Road 29 0 28 0

13. Flagg Ranch to Colter Bay 38 4 37 0

14. Colter Bay to Moran Junction 40 8 39 0

15. Moran Junction to East Entrance 45 12 43 4

16. Moran Junction to South Entrance 46 14 44 6

17. Teton Park Road No Veh. No Veh. No Veh. No Veh.

18. Moose-Wilson Road 28 0 26 0

19. Antelope Flats Snowmobile Route No Veh. No Veh. No Veh. No Veh.

20. Jackson Lake 54 7 52 0

Conclusion

Alternative D impacts about 57% to 61% of the acreage impacted by the no action

alternative for the three audibility categories. These percentages are the smallest of all

alternatives for the “audible at all” and “audible 10% or more” categories. For the

“audible 50% or more” category, they are the second smallest, being just slightly greater

than alternative G.

These large reductions are due to the required use of “clean and quiet” snowmobiles and

snowcoaches on all oversnow routes, and also due to the closing of the Fishing Bridge to

East Entrance and Teton Park Road segments. The reductions occur despite very little

change for the main contributor to the total acreage – the through traffic on US 26 the

Moran Junction to GTNP South Entrance segment.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

348

The contribution to the Leq is also reduced significantly due to 60-dB “clean and quiet”

snowmobiles and snowcoaches. It is reduced to zero decibels for those road segments

where all vehicular travel would be eliminated.

Effects on Cultural Resources

The effects on cultural resources would be the same as described in alternative B.

Conclusion

None of the actions described would adversely impact cultural resources.

Effects on Visitor Access and Circulation

Yellowstone National Park. Visitor access to park resources would be changed by

closing roadway segment 8 between Fishing Bridge and the East Entrance. Average

winter season activity at the East Entrance is about 4,100 winter use visitors.

Snowmobile passengers account for 85% of this use while almost all the remaining

winter use visitors entering the park through the East Entrance enjoy cross-country

skiing. Of the winter season average park visitation, activity at the East Entrance Station

accounts for about 3%. It is likely that these 4,100 visitors would use other recreation

areas outside the park, and would not travel to other park entrances.

Grand Teton National Park and the Parkway. Under this alternative Highway 89/287,

which currently provides wheeled-vehicle access to Flagg Ranch from both the south and

east, would be closed to wheeled-vehicles north of Colter Bay Village. As a mitigating

action, staging facilities at Flagg Ranch would be shifted to Colter Bay, providing the

same services at the new location. Lodging facilities and recreation at the Flagg Ranch

area would be maintained. Parking availability at Colter Bay exceeds that at Flagg

Ranch, resulting in no restrictions on current activity levels or in access to park resources

in YNP or GTNP. However, additional oversnow travel time would be required from

Colter Bay to the South Entrance of YNP.

Oversnow motorized opportunities would be limited to the CDST, Grassy Lake Road,

and the frozen surface of Jackson Lake. Alternative oversnow motorized opportunities

would not be provided in other areas of the park. Wheeled-vehicles access would be

eliminated between Colter Bay and Flagg Ranch. Nonmotorized circulation would be

enhanced along Teton Park Road between Jenny Lake and Signal Mountain. Overall

access would not be restricted by this alternative, as all areas of the park would remain

accessible through alternative modes of transportation.

A reasonably foreseeable distribution of vehicle use under this alternative is depicted in

the following table. It shows an average loss of 36.4 snowmobile trips daily from

Fishing Bridge to the East Entrance. There would be a net decrease of 2% in

snowmobile vehicle-miles traveled in the three park units and a net decrease of 2%

wheeled-vehicle-miles traveled. Snowcoach miles traveled would increase by less than

2%.
IMPACTS OF IMPLEMENTING ALTERNATIVE D

349

Table 108. Alternative D motorized use.

Average Daily Vehicle Use January-February

Road Segment Autos Vans Snowcoaches Snowmobiles Buses

Mammoth to Northeast Entrance No change from current condition

Mammoth to Norris No change from current condition

West Entrance to Madison No change from current condition

Madison to Norris No change from current condition

Norris to Canyon Village No change from current condition

Canyon Village to Fishing Bridge No change from current condition

Fishing Bridge to East Entrance 0 0 0 0 0

Fishing Bridge to West Thumb No change from current condition

Madison to Old Faithful No change from current condition

Old Faithful to West Thumb No change from current condition

West Thumb to Flagg Ranch No change from current condition

Grassy Lake Road No change from current condition

Flagg Ranch to Colter Bay 0 0 4 176 1

Colter Bay to Moran Junction No change from current condition

Moran Junction to East Entrance No change from current condition

Moran Junction to South Entrance No change from current condition

Teton Park Road 0 0 0 0 0

Moose-Wilson Road 10 2 0 0 0

Antelope Flats Snowmobile Route No change from current condition

Concession Services

Impacts would be the same as those described in alternative A. However, Pahaska

Teepee, a concessioner permitted to provide guided tours into the park, would no longer

be able to offer this service.

Concessions and services offered at Flagg Ranch in the Parkway, would be affected by

not plowing the highway north of Colter Bay. The segment connecting Colter Bay and

Flagg Ranch would be accessible via oversnow means only. Instead of wheeled-vehicle

access, most employees and clients would need to travel to and from the ranch by

snowmobile or snowcoach. Flagg Ranch would be snowbound, offering a more

specialized experience – similar to Old Faithful. This change represents a positive effect

on visitor experience or opportunities for visitors, but it would entail operational changes

and higher expenses for the concession owner.

Jackson-based tour operators would need to change their operations to accommodate

staging at Colter Bay, and a lengthened trip to Old Faithful. The change shortens the van

trip from Jackson by 32 miles (round trip) and lengthens the snowmobile round trip by
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

350

the same distance. Some operators believe that this would make the snowmobile trip to

Old Faithful too long for some clients. However, the overall length of the trip from

Jackson does not change, so the van portion of the trip would be shorter and safer and the

snowmobile portion would begin earlier.

The implementation of any alternative that might make substantial changes affecting a

concessioner would require negotiation between the NPS and the concessioner or be

deferred until a new concessions contract is awarded.

Conclusion

Winter use visitors accessing the East Entrance of YNP would experience adverse

impacts with the closing of road segment 8 between the East Entrance and Fishing

Bridge. However, only minor adverse impacts would occur to overall park access

because the 4,100 winter visitors using the East Entrance represent only 3% of winter

visitation. Most winter visitors would continue to access YNP through the entrances they

currently use. Negligible adverse impacts on park access would be expected at GTNP

and the Parkway because access to park resources would remain open, although the mode

of transportation or time allotted for travel would change.

Effects on Visitor Experience — Yellowstone National Park

The amount and type of winter visitor opportunities offered in YNP under alternative D

are provided in Table 109.

Table 109. YNP Visitor opportunities available under alternative D.

Opportunities Miles or

Areas

Increase/

Decrease Length of Season Other

Groomed motorized route 158.6 -25.4 Mid-December to

Mid-March

Late night closure

11 P.M. to 5 A.M.

Groomed motorized route

snowcoach only

0 0 Mid-December to

Mid-March

Late night closure

11 P.M. to 5 A.M.

Groomed motorized trail 15 +15 Mid-December to

Mid-March

Late night closure

11 P.M. to 5 A.M.

Plowed route 76 0 Mid-December to

Mid-March

Late night closure

11 P.M. to 5 A.M.

Groomed nonmotorized 43 +6 Mid-December to

Mid-March

Late night closure

11 P.M. to 5 A.M.

Warming huts 6 0 Mid-December to

Mid-March

Late night closure

11 P.M. to 5 A.M.

Backcountry 2.2 mm

acres

Use

restricted in

700,000

acres

Travel restricted to

trails in important

wildlife winter

range

None
IMPACTS OF IMPLEMENTING ALTERNATIVE D

351

Visitor Satisfaction and Experience

Opportunities to view wildlife. The East Entrance road closure would eliminate

wildlife viewing along that road segment, affecting the opportunities of 3% of all users.

Opportunities to view scenery. Same as no action alternative except that the East

Entrance closure eliminates scenery viewing along that road segment.

Safety (the safe behavior of others). Separation of groomed ski and snowmobile trails

would improve safety by decreasing user conflicts. An aggressive enforcement and

information program would result in an improved understanding of appropriate winter

recreation etiquette and behavior.

Quality of the groomed surface. The groomed routes from West Entrance to Madison

Junction to Old Faithful would be groomed more frequently and to a higher standard

under this alternative. Nighttime closure would increase the quality of the groomed

surface throughout the park.

The availability of access to winter activities or experiences. This alternative provides

an increase in motorized and nonmotorized trail opportunities throughout the park.

Nonmotorized activities are emphasized in the north and northeast sections of the park,

and motorized activities are emphasized in the west and southwest portions of the park.

Separation of these uses will enhance the winter quality of the experience for both user

groups.

Under alternative D the East Entrance road would be closed. This would eliminate the

oversnow motorized experience for 3% of snowmobile riders who use this entrance to

access the park.

Backcountry users would be restricted to designated routes in important winter range.

This action would result in a higher rate of skier encounters in these areas, and limit the

range of opportunities currently available to skiers.

Availability of information. This alternative would increase the number of warming

huts and interpretive programs offered in the park. By providing more information about

the attributes of the park that visitors value most, the winter visitor experience will be

enhanced. Increased warming huts and interpretive programs would afford visitors better

access to this information.

Quiet and Solitude. Because use in important wildlife winter range is restricted to

designated trails, skiers may find fewer opportunities to experience solitude.

Under alternative D all oversnow vehicles would be required to meet strict sound

standards. These standards would be implemented at various levels over the next 10

years. While the short-term changes in visitor experience would be minor, the long-term
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

352

goal of reducing snowmobile sound emissions to 60 dbA would moderately improve

opportunities to experience quiet in YNP.

Clean air. Under alternative D all oversnow vehicles would be required to meet strict

emissions standards. These standards would be implemented at various levels over the

next nine years. While the short-term changes in visitor experience would be minor, the

long-term goal of reducing snowmobile emissions would moderately enhance the ability

to experience clean air in YNP and particularly at the West Entrance and Old Faithful.

Conclusion

Under alternative D the availability of information and safety programs would provide

moderate beneficial improvements to the visitor experience. The increase in trail

opportunities would provide moderate beneficial effects on all user groups.

The reduction of snowmobile emissions and sound levels would, over time, provide

moderate beneficial improvements in opportunities for solitude, clean air, and natural

quiet.

Effects on Visitor Experience — Grand Teton National Park and the

Parkway

The amount and type of winter visitor opportunities offered in GTNP under alternative D

are provided in Table 110.

Table 110. GTNP Visitor opportunities available under alternative D.

OpportunIties

Miles or

Areas

Increase/

Decrease Length of Season Other

Groomed motorized route 20.3 18.2 December to

April†

Late night closure

Groomed motorized route,

snowcoach

20.3 18.2 December to

April†

Late night closure

Groomed motorized trail 15.7 -21 December to

April†

Late night closure

Plowed road 83.4 -16.6 December to

April†

Late night closure

Ungroomed motorized

trail or area

0 -35.6 December to

April†

Late night closure

Groomed nonmotorized 0 0 December to

April†

Late night closure

Ungroomed nonmotorized

trail or area

37.1 10.7 December to

April†

Late night closure

Warming huts/interpretive

centers

5 3 December to

April†

Late night closure

†

 Variable, dependent on snow conditions
IMPACTS OF IMPLEMENTING ALTERNATIVE D

353

Visitor Satisfaction and Experience

Opportunities to view wildlife. Same as in alternative B.

Opportunities to view scenery. Fewer opportunities would be provided to view scenery

by auto since there would be no wheeled-vehicle access north of Colter Bay.

Safety (the safe behavior of others). Motorized and nonmotorized uses would be

almost entirely separated in this alternative. The separation of snowmobiles and autos on

the CDST and elimination of auto traffic north of Colter Bay on the CDST would greatly

decrease the risk of motor vehicle accidents.

Quality of the groomed surface. Grooming would be enhanced on the Grassy Lake

Trail. The CDST north of Colter Bay would become a highly groomed route.

The availability of access to winter activities or experiences. There would be a mixed

impact under this alternative. Opportunities for use of ungroomed motor trails and open

use by snowmobiles on Jackson Lake would decrease. Angling opportunities by

snowmobilers would be lost. Counter to this loss would be increased opportunities for

nonmotorized activities on ungroomed trails.

Availability of information. There would be increased and enhanced visitor programs,

facilities, and interpretive opportunities to better meet the expectation and need for

information.

Quiet and Solitude. Same as in alternative B; however, opportunities for solitude via

motor access would be decreased, and opportunities for solitude via nonmotorized access

would be increased.

Clean air. Same as in alternative B.

Conclusion

Alternative E would have minor to negligible adverse impacts on opportunities for visitor

experience relating to wildlife and scenery viewing. There would be major beneficial

changes relating to safety by separating user groups entirely within the park. Improving

groomed surfaces on the CDST and Grassy Lake Road would result in a moderate

beneficial effect. Under alternative D visitor access to motorized activities would

decrease in the park’s interior. This action would result in moderate adverse effects on

users from this group. There would be a moderate beneficial impact to visitor experience

due to greatly increased availability of information, interpretation, and winter programs.

There would be a moderate beneficial impact relative to opportunities for quiet and

solitude. Opportunities to appreciate clean air would be moderately improved. Where

oversnow motorized use occurs, quiet and clean air would be facilitated by improved

motorized technology.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

354

IMPACTS OF IMPLEMENTING ALTERNATIVE E

Effects on the Socioeconomic Environment

In general alternative E is an adaptive management plan that offers no concrete policy

change proposals at present. It defers any possible changes to a future time when

scientific data is available upon which to base policy decisions. However, alternative E

does call for the cessation of most snowmobile use in GTNP and the Parkway, except for

access from Flagg Ranch on the Grassy Lake Road and towards YNP’s South Entrance.

The effects of these changes on the visitor expenditures are not quantifiable. In recent

years about 3,600 snowmobiles used the CDST and Teton Park Road. They would be

displaced, and a moderate reduction in visitor expenditures would occur. Lacking any

other specific changes in park management, estimated socioeconomic impacts are the

same as in alternative A, the no action alternative.

Regional Economy. No estimated impacts until future, unspecified policy changes are

implemented.

Minority and Low-Income Populations. No estimated impacts until future, unspecified

policy changes are implemented.

Social Values. No estimated impacts until future, unspecified policy changes are

implemented.

Nonmarket Values. No estimated impacts until future, unspecified policy changes are

implemented.

Conclusion

Alternative E is an adaptive management option. As such, no specific management

actions are proposed at this time, and no impacts are estimated.

Air Quality and Public Health

This alternative emphasizes the protection of wildlife and other natural resources while

allowing park visitors continued access to a range of winter recreation experiences. The

alternative also would create an advisory committee of federal and state governmental

representatives, environmental groups, and snowmobile industry experts to recommend

emission and sound standards for snowmobiles and the implementation of those

standards. This alternative is essentially the same as alternative A with respect to vehicle

operating activities, except that snowmobiles would not operate on the Flagg Ranch to

Colter Bay roadway, and bio-based lubricants and ethanol blend fuels would be sold in

the park. Table 111, Table 112, and Table 113 summarize the results of CO modeling for

six locations in the three parks for alternative E. Table 111 and Table 112 show the

predicted maximum 1-hour average CO concentrations and the calculated maximum 8-

hour average CO concentrations. The percent contribution of each vehicle type to the

maximum CO concentrations also is provided in Table 113 for the six locations. Table
IMPACTS OF IMPLEMENTING ALTERNATIVE E

355

114 and Table 115 provide corresponding model results for PM10 for the same locations

and conditions as those for CO.

Table 111. Maximum 1-hour average CO concentrations for alternative E.

Location

1-hr Maximum

Concentration

(w/o Background)

(ppm)

1-hr Maximum

Concentration

(w/Background)

(ppm)

Change Relative

to Alternative A

(w/o Background)

(%)

West Yellowstone Entrance 29.20 32.20 0

West Entrance to Madison Roadway 11.80 14.80 0

Old Faithful Staging Area 1.29 4.29 0

Flagg Ranch Staging Area 1.71 4.71 0.4

Flagg Ranch to Colter Bay Roadway 0.60 3.60 45.5

Mammoth to NE Entrance Roadway 0.30 3.30 0

Table 112. Maximum 8-hour average CO concentrations for alternative E.

Location

8-hr Maximum

Concentration

(w/o Background)

(ppm)

8-hr Maximum

Concentration

(w/Background)

(ppm)

Change Relative

to Alternative A

(w/o Background)

(%)

West Yellowstone Entrance 13.74†

15.15†0

West Entrance to Madison Roadway 5.55†

6.96†0

Old Faithful Staging Area 0.21 1.62 0

Flagg Ranch Staging Area 0.29 1.69 0.4

Flagg Ranch to Colter Bay Roadway 0.28†

1.69†45.5

Mammoth to NE Entrance Roadway 0.14†

1.55†0

†

 Estimated from the modeled maximum 1-hour average concentration based on the persistence formula

Ct2 = Ct1*(t1/t2)^0.365 (Cooper and Alley 1990).

Table 113. Vehicle contribution to CO concentrations for alternative E.

Contribution (%)

Location SM SC AM LT HT TB SV

West Yellowstone Entrance 97.9 2.0 0 0 0.1 0 0

West Entrance to Madison Roadway 98.6 1.4 0 0 0 0 0

Old Faithful Staging Area 98.1 1.9 0 0 0 0.1 0

Flagg Ranch Staging Area 68.6 1.3 8.3 16.8 0.1 0.1 4.8

Flagg Ranch to Colter Bay Roadway 0 0 23.6 58.8 0.4 0.3 17.1

Mammoth to NE Entrance Roadway 0 0 26.5 66.9 0.6 0 6.1

SM = snowmobile, SC = snowcoach, AM = automobile, LT = light truck, HT = heavy truck, TB = tour bus, SV = shuttle

van

Table 114. Maximum 24-hour average PM10 concentrations for alternative E.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

356

Location

24-hr Maximum

Concentration

(w/o Background)

(μg/m3)

24-hr Maximum

Concentration

(w/Background)

(μg/m3)

Change Relative to

Alternative A (w/o

Background) (%)

West Yellowstone Entrance 45.19† 68.19 0

West Entrance to Madison Roadway 10.74† 33.74 0

Old Faithful Staging Area 0.64 5.64 0

Flagg Ranch Staging Area 0.60 5.60 5.1

Flagg Ranch to Colter Bay Roadway 0.32† 5.32 66.7

Mammoth to NE Entrance Roadway 0.32† 5.32 0

†Estimated from the modeled maximum 1-hour average concentration based on the persistence formula

Ct2 = Ct1*(t1/t2)^0.365 (Cooper and Alley 1990).

Table 115. Vehicle contribution to PM10 concentrations for alternative E.

Contribution (%)

Location SM SC AM LT HT TB SV

West Yellowstone Entrance 99.3 0.2 0 0 0.5 0 0

West Entrance to Madison Roadway 97.6 1.1 0 0 1.3 0 0

Old Faithful Staging Area 99.8 0 0 0 0.2 0 0

Flagg Ranch Staging Area 99.2 0 0 0 0.5 0.3 0

Flagg Ranch to Colter Bay Roadway 0 0 19.3 39.6 16.1 13.4 11.5

Mammoth to NE Entrance Roadway 0 0 22.5 46.6 26.7 0 4.2

SM = snowmobile, SC = snowcoach, AM = automobile, LT = light truck, HT = heavy truck, TB = tour bus, SV = shuttle

van.

Visibility

The visibility assessment indicates that under this alternative, vehicular emissions would

cause localized, perceptible, visibility impairment near in the vicinity of the West

Entrance and in the area around Old Faithful and Flagg Ranch. The emissions along

heavily used roadway segments may also lead to localized, perceptible, visibility

impairment under certain viewing conditions.

Conclusion

As noted in Table 112, Table 113, and Table 114 the model predicts negligible, minor,

and moderate beneficial impacts on CO and PM10 levels relative to alternative A at the

West Entrance, along the West Entrance to Madison roadway, and at the two staging

areas, respectively. Along the Flagg Ranch to Colter Bay roadway, moderate, and major

beneficial impacts on CO and PM10 concentrations are predicted. These decreased

concentrations are attributable to the prohibition of snowmobiles on this roadway.

Effects on Public Safety

Reducing the nighttime speed limit for oversnow travel in both parks between sunset and

sunrise from 45 mph to 35 mph would reduce the potential for oversnow accidents. In

the last three years in YNP, about 11% of the oversnow accidents occurred at night; 40%

of these accidents involved wildlife-vehicle collisions.
IMPACTS OF IMPLEMENTING ALTERNATIVE E

357

This alternative allows for the closure of certain road segments if scientific study

indicates that human presence or activities have detrimental effects on wildlife that

cannot otherwise be mitigated. Should such closures be implemented, the potential for

safety conflicts in these areas would be eliminated.

Within GTNP and the Parkway, oversnow motorized travel would be restricted to Grassy

Lake Road and north of Flagg Ranch to the southern boundary of YNP. This would

result in a substantial reduction of the present inter-modal accident potential within the

park. Elimination of both snowmobiles and snowplanes from the surface of Jackson

Lake would also eliminate the potential for inter-modal conflicts and accidents involving

the failure of ice.

Conclusion

The effects of reducing oversnow nighttime speed limits would be negligible to minor in

all three park units. Should roads be closed to oversnow travel because of demonstrated

wildlife disturbance, the result also would be a major beneficial improvement to public

safety in those areas. An overall decrease in oversnow motorized travel would result in

moderate beneficial improvements in public safety in GTNP. These impacts would

affect employees and visitors.

Effects on Geothermal Features

Under alternative E park roads and nonmotorized trails at Mammoth Terraces and the

Lone Star Geyser Basin would be groomed. The effects of these actions on the

geothermal features associated with roads and trails near destination areas would have the

same impacts as those described in alternative A.

The beneficial impacts (relative to alternative A) on geothermal features from restricted

backcountry use and the adaptive management provisions would be the same as those

described in alternative B.

Conclusion

Under this alternative there would be major benefits to the geothermal resources in YNP

as compared to no action alternative. Increased benefits would result from restricted

backcountry use, scientific studies and monitoring leading to mitigation or possible

closures where adverse impacts occur, and no new developments. Overall, this

alternative would have a major beneficial effect on the protection of geothermal features.

Effects on Water and Aquatic Resources

Potential pollution sources are the same as described in alternative A. The potential

impacts along “high” risk road segments are the same as described in alternative A, with

the following exceptions. Risks of water pollution along the Canyon Village to Fishing

Bridge and Colter Bay to Moran Junction “high-risk” road segments would decrease as

snowmobiles decrease or are prohibited. Risk of water pollution along the “low-risk”
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

358

road segments would be decreased with the prohibition of snowmobiles (Flagg Ranch to

Colter Bay Road) or elimination of all vehicles (Teton Park Road and Moose-Wilson

Road).

Table 11640. Snowmachines and associated risk levels for alternative E.

Impact: Daily Vehicle

Miles Traveled Along

the Segment in Alt.

A*

Impact: Daily Vehicle

Miles Traveled Along

the Segment in Alt.

E*

Road Segment

Risk ±

Rating SM SC SM SC

Mammoth to Norris Medium 641 69 641 69

West Entrance to Madison Medium 7,759 127 7,759 127

Madison to Norris High 3,458 73 3,458 73

Norris to Canyon Village Low 2,214 47 2,214 47

Canyon Village to Fishing Bridge High 2,370 50 2,370 50

Fishing Bridge to East Entrance Medium 983 0 983 0

Fishing Bridge to West Thumb Medium 2,627 55 2,627 55

Madison to Old Faithful High 7,818 165 7,818 165

Old Faithful to West Thumb Medium 3,560 73 3,560 73

West Thumb to Flagg Ranch Medium 4,219 103 4,219 103

Grassy Lake Road High 184 0 200 0

Flagg Ranch to Colter Bay Low 379 0 400 0

Colter Bay to Moran Junction High 248 0 0 0

Moran Junction to East Entrance Medium 49 0 0 0

Teton Park Road Low 156 0 0 0

Moose-Wilson Road Low 6 0 0 0

Conclusion

Two-stroke engine emissions would continue to deposit pollution into snowpack along

groomed park roads in YNP and GTNP. The effect of this deposition on water quality is

undetermined, but there is currently no evidence of measurable changes in water quality

or effects on aquatic resources. It is possible that accumulations of pollutants in aquatic

systems may have adverse impacts on wetlands and aquatic resources downstream from

high risk road segments. Continued oversnow vehicle use at current levels in YNP

involves localized high risk to surface water quality along 22% of the road segments in

the three park units, with the exception of the Colter Bay to Flagg Ranch segment. The

risk of moderate to major adverse impacts on water quality in Jackson Lake would be

eliminated. The continued use of bio-based fuels by the NPS and the availability of fuels

in gateway communities may result in a minor decrease in pollutant deposition into snow.

 

40 *SM = Snowmobile, SC = Snowcoach. The source of pollutants is emissions from snowmobiles, which

produce (conservatively) ten times as many emissions per mile as most wheeled vehicles. Single

snowcoaches produce fewer emissions then single snowmobiles.

±High = within 100 meters of aquatic system on 76% to 100% of the road segment; Medium = within 100

meters on 51% to 75% of the road segment; Low risk segments are within 100 meters of rivers less than 50%.
IMPACTS OF IMPLEMENTING ALTERNATIVE E

359

Mitigation

Best management practices would be used during the construction, reconstruction, or

winter plowing of trails and roads to prevent unnecessary vegetation removal, erosion,

and sedimentation. The release of snowpack contaminants into surface water could be

mitigated by disconnecting snowmelt drainages from trails used by oversnow vehicles.

Any new or reconstructed winter use sanitary facilities would be constructed in locations

and using advanced technologies that would protect water resources. A focused program

of monitoring would reduce the uncertainty of impacts from oversnow vehicles, and if

necessary, indicate best management practices.

Effects on Wildlife

Ungulates

Effects of groomed roads and trails. Packed trails may influence wildlife movements

and distributions by facilitating travel into areas that would normally be inaccessible due

to deep snow. Under alternative E in GTNP, the only oversnow motorized use would

occur on 8 miles of the Grassy Lake Road and 2 miles of the groomed route north of

Flagg Ranch (a decrease of 26 miles). YNP would groom 221 miles, the same as under

current management.

Relative to alternative A, the effects associated with packed routes would be nearly

eliminated in GTNP. Effects in YNP would be the same as alternative A.

Effects of motorized oversnow use of groomed and ungroomed roads and trails. The

use of motorized oversnow vehicles can cause displacement from preferred habitats and

injury and death to wildlife, especially in poor lighting conditions and during snowfall.

Relative to alternative A, the effects associated with oversnow motorized use would be

nearly eliminated in GTNP. Effects in YNP would be the same as alternative A.

Effects of plowed roads. Road plowing may cause habitat fragmentation by creating

structural barriers (i.e., snow berms) to ungulate movements (Aune 1981). In addition

plowed roads, like groomed roads, may also provide an energy efficient mechanism for

wildlife movements, including bison, elk, and moose. Under alternative E GTNP would

plow 94 miles (6 less than currently) and YNP would plow 76 (the same as now).

Effects associated with plowed roads would be the same as in alternative A. In GTNP,

highway 89/287 would continue to intersect and parallel riparian habitat between the

Buffalo Fork, Snake River, and Willow Flats, although the CDST would no longer exist

through the park. Moose-vehicle collisions would continue to occur each year, but would

represent a negligible impact as compared to the total population in GTNP.

Effects of motorized use of plowed roads. The effects of plowed roads are similar to

those of groomed roads, except that the magnitude of the effect is usually greater. The

use of motorized vehicles on plowed roads can cause displacement from preferred
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

360

habitats and injury and death to wildlife, especially in poor lighting conditions, at dusk

and dawn, and during snowfall.

Effects of plowed roads would be essentially the same as alternative A.

Effects of nonmotorized use of groomed and designated ungroomed routes. The

primary effects of nonmotorized use on ungulates are displacement from preferred

habitats, especially geothermal areas that are important for winter survival in YNP, and

increased energy expenditures, including physiological stress, which may reduce

individuals’ chances of survival. Under alternative E GTNP would establish 8 new miles

of new nonmotorized routes, and YNP would offer 37 miles, the same as now.

In GTNP the types of impact in this alternative are similar to those described in

alternative B, but at a lower magnitude. The elimination of nonmotorized routes in the

Antelope Flats area would eliminate impacts on wintering elk, moose, and deer around

Blacktail Butte.

Effects of unregulated backcountry nonmotorized use. Unregulated backcountry,

nonmotorized use is more random and infrequent compared to nonmotorized use on

designated routes. Consequently, although encounters between backcountry users and

ungulates may only occur sporadically, they can be especially disturbing and lead to

additional energy expenditure and stress that reduces animals’ chances of survival and

reproduction. Alternative E minimizes the potential for these effects in YNP by

eliminating or restricting backcountry use in important winter habitats (e.g., thermally

influenced areas). Use, where permitted, would be limited to designated routes. Because

winter habitats in GTNP are already closed to public access in several areas, no new

restrictions on use in this park are proposed under alternative E.

Impacts related to backcountry use in alternative E would be reduced compared to

current management in YNP. In GTNP moderate to major adverse impacts on bighorn

sheep would continue, as well as potential impacts to moose, elk, and bison on Blacktail

Butte and Wolff Ridge.

Effects of the presence and use of winter support facilities. Increases in human

activity associated with the presence of support facilities may displace species sensitive

to human disturbance. There are no new warming facilities proposed in this alternative.

Potential impacts are generally as stated in alternative A — minor.

Federally Protected Species

Effects of groomed roads and trails. Packed trails may influence wildlife movements

and distributions by facilitating travel into areas that would normally be inaccessible due

to deep snow. Under alternative E in GTNP, the only oversnow motorized use would

occur on 8 miles of the Grassy Lake Road and on 2 miles of the groomed route north of
IMPACTS OF IMPLEMENTING ALTERNATIVE E

361

Flagg Ranch (a decrease of 26 miles). YNP would groom 221 miles, the same as under

current management.

Relative to alternative A, the effects associated with packed routes would be nearly

eliminated in GTNP. Effects in YNP would be the same as alternative A.

Effects of motorized use of groomed and ungroomed roads and trails. The use of

motorized oversnow vehicles can cause displacement from preferred habitats. No

collisions have occurred between oversnow motorized vehicles and federally protected

species in the parks.

Relative to alternative A, the effects associated with motorized use would be nearly

eliminated in GTNP. Effects in YNP would be the same as alternative A.

Effects of plowed roads. Road plowing may cause habitat fragmentation by creating

structural barriers (i.e., snow berms) to wildlife movements (Aune 1981). In addition

like groomed roads, plowed roads may influence wildlife movements and distributions by

facilitating travel for wildlife into areas that would normally be inaccessible due to deep

snow. Under alternative E, GTNP would plow 94 miles (6 less than currently) and YNP

would plow 76 (the same as currently).

Impacts are generally as stated in alternative A.

Effects of motorized use of plowed roads. The effects of traffic on plowed roads are

similar to those on groomed roads, except that the magnitude of the effect is usually

greater. The use of motorized vehicles on plowed roads can cause displacement from

preferred habitats and injury and death to wildlife, especially in poor lighting conditions,

at dusk and dawn, and during snowfall.

Impacts are generally as stated in alternative A — none to minor. If federally protected

species activity is known to occur in an area, park managers can close the area to human

activity to prevent disturbance.

Effects of nonmotorized use on groomed and designated ungroomed routes. The

primary effects of nonmotorized use on wildlife are displacement from preferred habitats

and increased energy expenditures, including physiological stress, which may reduce

individuals’ chances of survival. Under alternative E, GTNP would establish 8 miles of

new nonmotorized routes, and YNP would offer 37 miles, the same as currently.

Potential impacts are generally as stated in alternative A — none to negligible. If

federally protected species activity is known to occur in an area, park managers can close

the area to human activity to mitigate disturbance.

Effects of unregulated backcountry nonmotorized use. Unregulated backcountry

nonmotorized use is more random and infrequent relative to nonmotorized use on

designated routes. Consequently, although encounters between backcountry users and
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ENVIRONMENTAL CONSEQUENCES

362

federally protected wildlife species may only occur sporadically, they may cause

displacement and additional energy expenditure and stress that reduces animals’ chances

of survival and reproduction. Alternative E minimizes the potential for these effects in

YNP by eliminating or restricting backcountry use in important winter habitats (e.g.,

thermally influenced areas). Use, where permitted, would be limited to designated

routes. Because winter habitats in GTNP are already closed to public access in several

areas, no new restrictions on use in this park are proposed under this alternative.

Impacts related to backcountry use in alternative E would be reduced compared to

current management in YNP. Impacts in GTNP would remain the same — negligible to

minor.

Presence and use of winter support facilities. Warming huts and campgrounds can

cause habituation in some wildlife species by the presence of human food and garbage,

and can lead to human-wildlife conflicts. In addition increases in human activity

associated with the presence of support facilities may displace species sensitive to human

disturbance. There are no new warming facilities proposed in this alternative.

Potential impacts are generally as stated in alternative A — negligible to minor. If

protected species activity is detected, park managers can close the area to human activity

to mitigate disturbance.

Species of Special Concern

Effects of groomed roads and trails. Packed trails may influence wildlife movements

and distributions by facilitating travel into areas that would normally be inaccessible due

to deep snow; inhibit foraging activities of carnivores that tunnel beneath the snow to

hunt subnivian prey; and reduce subnivian prey availability by increasing mortality of

these small mammals. Under alternative E in GTNP, the only oversnow motorized use

would occur on 8 miles of the Grassy Lake Road and on 2 miles of the groomed route

north of Flagg Ranch, and YNP would groom the same amount as currently (221 miles).

For YNP effects are generally as stated in alternative A — none to negligible. In GTNP

effects associated with groomed routes would be nearly eliminated due to the closure of

most packed surfaces in GTNP.

Effects of motorized oversnow use of groomed and ungroomed roads and trails. The

most likely impacts to species of special concern are displacement from preferred

habitats, and degradation of the aquatic environment from pollutants in the snowpack.

Documented mortality caused by collisions with oversnow vehicles in the parks is rare.

In 10 years only one of these species (a marten) was reportedly killed by a snowmobile in

YNP (Gunther et al. 1998).

For YNP effects are generally as stated in alternative A — none to minor. In GTNP

effects associated with groomed routes would be nearly eliminated due to the closure of
IMPACTS OF IMPLEMENTING ALTERNATIVE E

363

most of motorized trails in GTNP. If species activity is detected, park managers can

close the area to human activity to prevent disturbance.

See Water and Aquatic Resources, Chapter IV for an assessment of the impacts of

exhaust on water quality in the parks.

Effects of plowed roads. Similar to groomed roads, plowed roads also provide an

energy efficient mechanism for wildlife movements. Under alternative E, GTNP would

plow 94 miles (6 less than alternative A) and YNP would plow 76 (the same as

alternative A).

Impacts are generally as stated in alternative A. If species activity is known to occur in

an area, park managers can close the area to human activity to prevent disturbance.

Effects of motorized use of plowed roads. The most likely impact to park species of

special concern is displacement from preferred habitats and mortality caused by

collisions with wheeled-vehicles.

Impacts are generally as stated in alternative A. If species activity is known to occur in

an area, park managers can close the area to human activity to prevent disturbance.

Effects of nonmotorized use on groomed and ungroomed designated routes. The

primary effects of nonmotorized use are displacement from preferred habitats, and

increased energy expenditures, including physiological stress, which may reduce

individuals’ chances of survival. Under alternative E, GTNP would establish 8 new

miles of new nonmotorized routes, and YNP would offer 37 miles, the same as now.

Impacts are as stated generally in alternative A — none to minor.

Unregulated backcountry nonmotorized use. Unregulated backcountry nonmotorized

use is more random and infrequent than nonmotorized use on designated routes.

Consequently, although encounters between backcountry users and species of special

management concern may only occur sporadically, they can be especially disturbing and

lead to additional energy expenditure and stress that reduces animals’ chances of survival

and reproduction. This alternative mitigates potential effects associated with these

activities in YNP by eliminating unregulated backcountry use in winter range. Use

would be limited to designated routes, and routes would only be designated in areas

where species’ needs are not of concern.

Effects associated with backcountry use would decrease from alternative A in YNP and

in GTNP and the Parkway. Impacts are generally as stated in alternative A.

Presence and use of winter support facilities. The primary effects of warming huts and

campgrounds on park species of special concern are associated with increases in human

activity, and the subsequent disturbance and displacement of species or their prey. There

are no new warming facilities proposed in this alternative. Potential impacts are
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ENVIRONMENTAL CONSEQUENCES

364

generally as stated in alternative A — none to minor. If species activity is detected, park

managers can close the area to human activity to mitigate disturbance.

Conclusion

This alternative emphasizes the protection of wildlife while allowing park visitors access

to a range of winter recreation opportunities. For YNP with the exception of regulated

backcountry use, the effects of this alternative are generally the same as for alternative A.

In GTNP all impacts associated with oversnow motorized use greatly decrease. Adaptive

management requires a proactive approach to monitoring impacts on wildlife. Should it

be determined that impacts are occurring contrary to regulations or management

objectives, use would be restricted or eliminated. Implementation of this feature would

distinguish this alternative from alternative A for YNP, by eliminating long-term effects.

Impacts to populations resulting from winter recreation are neither long-term nor

significant. However, impacts to individual members of the population can lead to death,

either directly from collisions or continued harassment, or indirectly through

management actions taken as a response to habituation to human presence and food.

Although concerned about impacts on individuals, the NPS primarily provides for the

protection of native animals populations from management actions (with the exception of

federally protected species). For example, see Chapter II, NPS 77, Natural Resources

Management.

Ungulates

• Effects of groomed roads and trails on animal movements — unknown if and to what

extent beneficial effects outweigh negative effects. Any effects associated with groomed

trails would be greatly decreased in GTNP as compared to alternative A; effects in YNP

would remain the same as alternative A.

• Effects of motorized oversnow use of groomed and ungroomed roads and trails on: 1)

mortality caused by collisions – adverse, negligible, and short term and 2) displacement

from preferred habitats – adverse, moderate, and short term. Described effects apply to

YNP and are the same as alternative A; in GTNP effects would be greatly reduced as

compared to alternative A.

• Effects of plowed roads on: 1) habitat fragmentation – adverse, minor, and short term; and

2) animal movements – unknown if and to what extent beneficial effects outweigh negative

effects. Same as alternative A.

• Effects of motorized use of plowed roads on: 1) mortality caused by collisions – adverse,

minor, and short term; and 2) displacement from preferred habitats – adverse, moderate,

and long-term. Same as alternative A.

• Effects of nonmotorized use of groomed and designated ungroomed routes on displacement

from preferred habitats – adverse, minor, and short term. In GTNP effects would be

slightly greater than alternative A, although the elimination of nonmotorized use in the

Antelope Flats area would reduce disturbance to wintering ungulates. Effects in YNP

would be the same as alternative A.

• Effects of unregulated backcountry nonmotorized use on displacement from preferred

habitats – adverse, negligible to minor, and short term in YNP (a decrease from alternative

A due to the elimination of unregulated backcountry use); and adverse, moderate, and short

term in GTNP (the same as alternative A). Impacts to bighorn sheep in GTNP would

remain moderate to major and long-term if no mitigation is applied.

• Effects of the presence and use of winter support facilities on displacement – adverse,

minor, and short term. Same as alternative A.
IMPACTS OF IMPLEMENTING ALTERNATIVE E

365

Federally Protected Species

• Effects of groomed roads and trails on animal movements: 1) bald eagles, grizzly bears,

and wolves — no effect; and 2) lynx – adverse, negligible to major, and short term,

depending upon lynx distribution and abundance in the parks. Described effects apply to

YNP, and effects would be greatly decreased in GTNP as compared to alternative A.

• Effects of motorized oversnow use of groomed and ungroomed roads and trails on

displacement from preferred habitats – adverse, negligible, and short term for all species

excluding the grizzly bear, which, for the most part, will not be active during the winter use

season. Described effects apply to YNP; effects would be greatly decreased in GTNP as

compared to alternative A.

• Effects of plowed roads on: 1) habitat fragmentation – no effect on any of the listed

species; and 2) animal movements – no known effect on any of the listed species. Same as

alternative A.

• Effects of motorized use of plowed roads on: 1) mortality caused by collisions – adverse,

negligible, and short term on bald eagles and grizzly bears; adverse, minor, and short term

on wolves; no known effect to date on lynx; and 2) displacement from preferred habitats –

adverse, negligible, and short term on bald eagles, no effect on grizzly bears; no known

effect to date on wolves and lynx. Same as alternative A.

• Effects of nonmotorized use of groomed and designated ungroomed routes on displacement

from preferred habitats – adverse, negligible, and short term on bald eagles; no effect on

grizzly bears; and no known effect to date on wolves and lynx. Same as alternative A.

• Effects of unregulated backcountry nonmotorized use on displacement from preferred

habitats – adverse, minor, and short term on bald eagles; adverse, negligible, and short term

on grizzly bears; adverse, minor, and short term on wolves; and no known effect to date on

lynx. Described effects apply to GTNP and are the same as alternative A; effects would

decrease in YNP because of the elimination of unregulated backcountry use.

• Effects of the presence and use of winter support facilities on displacement – no affect on

bald eagles; adverse, negligible, and short term on grizzly bears, with mitigation; adverse,

minor, and short term on wolves; and no effect on lynx. Same as alternative A.

Species of Special Concern

• Effects of groomed roads and trails on 1) animal movements – no known effect on

wolverines; adverse, negligible, and short term on fishers and martens; no effect on otters,

swans, reptiles, amphibians, and fish; 2) foraging activities – adverse, negligible, and short

term on marten; no effect on the other species; and 3) subnivian prey availability —

adverse, negligible, and short term on marten; and no effect on the other species.

Described effects apply to YNP; effects may greatly decrease relative to alternative A in

GTNP.

• Effects of motorized oversnow use of groomed and ungroomed roads and trails on

displacement – no known effect on wolverine; adverse, negligible, and short term on

fishers, marten; no effect on otters, reptiles, amphibians, and fish; and adverse, minor, and

short term on swans. Described effects apply to YNP; effects may greatly decrease relative

to alternative A in GTNP.

• Effects of plowed roads on animal movements – no known effect on wolverines, fishers,

and martens; and no effect on otters, swans, reptiles, amphibians, and fish. Same as

alternative A.

• Effects of motorized use of plowed roads on displacement from preferred habitats: 1)

adverse, negligible, and short term on wolverines, fishers, and martens; no effect on otters,

swans, reptiles, amphibians, and fish; and 2) mortality from collisions — adverse,

negligible, and short term on otters, martens; and no effect to date on other species. Same

as alternative A.

• Effects of nonmotorized use of groomed and designated ungroomed routes on displacement

from preferred habitats – no effect on wolverines; no known effect on fishers, martens, and
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ENVIRONMENTAL CONSEQUENCES

366

otters; adverse, minor, and short term on swans; adverse, negligible, and short term on

sagebrush lizard; and no effect on rubber boa, amphibians, and fish. Same as alternative A.

• Effects of unregulated backcountry nonmotorized use on displacement from preferred

habitats – adverse, negligible, and short term on wolverines and sagebrush lizard; no

known effect on fishers, martens, and otters; adverse, minor, and short term on swans; and

no effect on rubber boa, amphibians, and fish. Described effects apply to GTNP and are

the same as alternative A; effects would decrease in YNP because of the elimination of

unregulated backcountry use.

• Effects of the presence and use of winter support facilities on displacement of potential

prey (carcass) availability – adverse, minor, and short term on wolverines, fishers, and

martens; no effect on swans, rubber boa, amphibians, and fish; no known effect on otters;

and adverse, minor, and short term on sagebrush lizard. Same as alternative A.

Mitigation

• Backcountry monitoring and administration should be implemented in GTNP. Additional

area closures could be imposed if monitoring indicates such a closure is warranted for the

protection of wintering ungulates.

• Use of groomed and plowed surfaces by bison and other ungulates would continue to be

monitored.

• Snow track surveys for carnivores, including lynx, on both groomed and ungroomed routes

would be conducted.

Effects on Natural Soundscape

Audibility analysis — combined effects of all wheeled and oversnow vehicles

Table 117 presents the acres of park land by road segment where any wheeled or

oversnow vehicle noise would be audible under the two background conditions,

“average” and “quiet,” as defined in the Assumptions and Methodologies section of this

chapter. For each background condition, acreage is presented for three categories of

audibility: 1) audible for any amount of time (labeled “audible at all”); 2) audible for

10% of the time or more; and 3) audible for 50% of the time or more. Appendix M

contains tables with distances to audibility for each segment for each alternative.

Alternative E features no snowplanes or snowmobiles on Jackson Lake, and no oversnow

vehicles elsewhere in GTNP except from Flagg Ranch to YNP and on Grassy Lake Road.

The results for alternative E show that for the “average” background conditions, wheeled

or oversnow vehicles would be audible to some degree for over 152,000 acres in the three

park units. For nearly 82,000 of those acres, wheeled or oversnow vehicles would be

audible for at least 10% of the time during the day. For over 23,000 of those acres, they

would be audible for at least half of the time during the day. These acreages increase by

10% to 13% for the “quiet” background conditions for the three audibility categories.

Table 117. Acres of park land affected by vehicle audibility for alternative E.

With Average Background

Conditions

With Quiet Background

Conditions

Road Segment Miles

Audible

at All

Audible 10%

of the Time

or More

Audible 50%

of the Time

or More

Audible

at All

Audible

10% of

the Time

or More

Audible

50% of

the Time

or More
IMPACTS OF IMPLEMENTING ALTERNATIVE E

367

1. Mammoth to Northeast Entrance 47 16,126 5,445 0 16,822 6,342 0

2. Mammoth to Norris 21 11,400 761 0 12,372 1,043 0

 3. West Entrance to Madison 14 8,032 6,482 5,282 10,090 7,060 6,032

4. Madison to Norris 14 6,853 5,505 347 7,249 6,029 419

5. Norris to Canyon Village 12 5,443 3,955 0 5,683 4,420 0

6. Canyon Village to Fishing Bridge 16 9,999 6,559 0 11,173 7,426 166

7. Fishing Bridge to East Entrance 27 10,760 1,381 0 11,762 1,582 0

8. Fishing Bridge to West Thumb 21 15,645 9,490 0 17,785 10,884 0

9. Madison to Old Faithful 16 8,781 7,583 5,546 11,064 8,324 6,604

10. Old Faithful to West Thumb 17 7,713 6,057 0 8,053 6,647 0

11. West Thumb to Flagg Ranch 24 12,716 8,780 664 13,577 9,884 933

12. Grassy Lake Road 7.6 3,033 0 0 3,303 0 0

13. Flagg Ranch to Colter Bay 15.6 7,532 2,761 0 8,183 3,037 0

14. Colter Bay to Moran Junction 10.2 4,605 1,884 0 4,953 2,098 0

15. Moran Junction to East Entrance 2 1,193 709 476 1,294 781 519

16. Moran Junction to South Entrance 26 21,714 14,462 11,120 23,842 16,827 11,823

17. Teton Park Road 15 No Veh. No Veh. No Veh. No Veh. No Veh.No Veh.

18. Moose-Wilson Road 2.5 659 0 0 695 0 0

19. Antelope Flats Snowmobile Route -- No Veh. No Veh. No Veh. No Veh. No Veh.No Veh.

20. Jackson Lake 9.7 No Veh. No Veh. No Veh. No Veh. No Veh.No Veh.

TOTAL 152,203 81,815 23,436 167,899 92,382 26,497

The segment from Moran Junction to the South Entrance of GTNP, which carries a great

deal of wheeled-vehicle traffic unrelated to the alternatives, contributes the greatest to the

total acreage values for all three audibility categories. These amounts remain almost

constant for all the alternatives.

The plowed road from Mammoth to the YNP Northeast Entrance is a major contributor

to the “audible at all” acreage (and, to a lesser extent, “audible 10% or more”), which

remains virtually unchanged across all the alternatives.

The other major road segments for the “audible 50% or more” categories are from the

West Entrance of YNP to Madison and from Madison to Old Faithful.

The audibility acreage is reduced to zero for Jackson Lake and Teton Park Road. There

are only slight reductions for the Colter Bay to Moran Junction and Flagg Ranch to

Colter Bay segments compared to the no action alternative.

Average Sound Level Analysis

To give a sense of the effect of the number of oversnow or wheeled-vehicles on a road

segment, and their speed and sound level, Table 118 shows the computed hourly

equivalent or “average” sound level (Leq) over the daytime period. Levels are shown for

each road segment at two distances, 100 feet and 4,000 feet, and for both open and
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ENVIRONMENTAL CONSEQUENCES

368

forested terrain. These hourly Leq values do not have the background sound level added

in to them. Also they cannot be compared against the background levels to assess

audibility, since Leq represents a long-term average of both quiet and loud moments.

The hourly Leq values at 100 feet are highest for West Entrance to Madison, and Madison

to Old Faithful segments mentioned above. At 4,000 feet away, the Leq are highest for

these two segments, followed by all the YNP inner loop segments, and the segments from

Moran Junction to both the East Entrance and the South Entrance of GTNP. The

oversnow vehicle contributions to the Leq are reduced to zero for Jackson Lake, Teton

Park Road, and Antelope Flats, and there is a 7 dB reduction along the Flagg Ranch to

Colter Bay segment.

Conclusion

Alternative E impacts about 84% to 86% of the acreage impacted by the no action

alternative for the “audible at all” and “audible 10% of the time or more” categories. It

impacts the same total acreage as the no action alternative for the “audible 50% or more”

categories. The reason for the decreases in the first two categories is the elimination of

oversnow vehicles on Jackson Lake and Teton Park Road in GTNP.

The contribution to the Leq is reduced to zero for those road segments where vehicular

travel of all types is eliminated, as well as Jackson Lake.
IMPACTS OF IMPLEMENTING ALTERNATIVE E

369

Table 118. Average hourly Leq from wheeled and oversnow vehicle noise at two

distances to each road segment for alternative E.

Leq at Distance (dBA)

Open Terrain Forested Terrain

Road Segment 100 feet 4,000 feet 100 feet 4,000 feet

1. Mammoth to Northeast Entrance 35 2 33 0

2. Mammoth to Norris 44 4 42 0

3. West Entrance to Madison 56 16 54 8

4. Madison to Norris 53 13 51 5

5. Norris to Canyon Village 51 12 50 4

6. Canyon Village to Fishing Bridge 50 10 49 2

7. Fishing Bridge to East Entrance 44 4 43 0

8. Fishing Bridge to West Thumb 50 10 48 2

9. Madison to Old Faithful 56 16 54 8

10. Old Faithful to West Thumb 52 12 50 4

11. West Thumb to Flagg Ranch 51 11 50 3

12. Grassy Lake Road 42 2 41 0

13. Flagg Ranch to Colter Bay 37 5 36 0

14. Colter Bay to Moran Junction 40 8 38 0

15. Moran Junction to East Entrance 45 12 43 4

16. Moran Junction to South Entrance 46 14 44 6

17. Teton Park Road No Veh. No Veh. No Veh. No Veh.

18. Moose-Wilson Road 34 0 32 0

19. Antelope Flats Snowmobile Route No. Veh No. Veh No. Veh No Veh.

20. Jackson Lake No. Veh No. Veh No. Veh No Veh.

Effects on Cultural Resources

The effects on cultural resources would be the same as described in alternative B.

Conclusion

None of the actions described would adversely impact cultural resources.

Effects on Visitor Access and Circulation

Yellowstone National Park. Under alternative E access to park resources would not

change unless area closures occur within the park to protect resources such as water

quality, air quality, or wildlife. The effects of area closures on access would have to be

evaluated in future environmental compliance documents as the closures were proposed.

Grand Teton National Park and the Parkway. The only measurable or perceptible

change to access would be the elimination of the CDST along Highway 89/287 between

the east park boundary and Flagg Ranch. CDST users would be shuttled from the end of
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

370

the trail to Flagg Ranch. A relatively small number of winter use visitors who use the

CDST would be affected. Access to Flagg Ranch would continue. However, other

modes of travel (such as wheeled-vehicles) would be used, in addition to continued

oversnow access via the Grassy Lake Trail. Under alternative E, overall visitor access to

park resources would not be expected to change.

Table 119 depicts reasonably foreseeable distribution of vehicle use as a consequence of

this alternative. It shows a loss of 87 snowmobile trips daily from the Teton Park Road

and the CDST from GTNP’s East Entrance to Flagg Ranch. There would be a decrease

of 2% in snowmobile vehicle-miles traveled in the three park units and a net increase of

4% wheeled-vehicle-miles traveled. Snowcoach travel would remain the same as in

alternative A.

Table 119. Alternative E motorized use.

Average Daily Vehicle Use January-February

Road Segment Autos Vans Snowcoaches Snowmobiles Buses

Mammoth to Northeast Entrance No change from current condition

Mammoth to Norris No change from current condition

West Entrance to Madison No change from current condition

Madison to Norris No change from current condition

Norris to Canyon Village No change from current condition

Canyon Village to Fishing Bridge No change from current condition

Fishing Bridge to East Entrance No change from current condition

Fishing Bridge to West Thumb No change from current condition

Madison to Old Faithful No change from current condition

Old Faithful to West Thumb No change from current condition

West Thumb to Flagg Ranch No change from current condition

Grassy Lake Road No change from current condition

Flagg Ranch to Colter Bay 86 15 0 0 1

Colter Bay to Moran Junction 192 15 0 0 1

Moran Junction to East Entrance 560 35 0 0 2

Moran Junction to South Entrance No change from current condition

Teton Park Road 0 0 0 0 0

Moose-Wilson Road 5 0 0 0 0

Antelope Flats Snowmobile Route No change from current condition

Concession Services

Impacts would essentially be the same as those described in alternative A for all three

park units.

The CDST would be discontinued at the east boundary of GTNP, so snowmobilers would

no longer be able to come into Flagg Ranch over the snow and from the east. The
IMPACTS OF IMPLEMENTING ALTERNATIVE E

371

amount of business actually provided by Flagg Ranch to such users (fuel, lodging, and

groceries) is unknown, but those users are relatively few. Those snowmobilers who

presently engage in this activity would have a shuttle system available to them in this

alternative for transport from the east boundary to Flagg Ranch. A concession provided

shuttle service may create jobs and generate some income for existing or new

concessioners.

Conclusion

The short-term impact to access is negligible in YNP. However, impacts are unknown

and would depend on future management decisions related to area closures. Access to

resources in GTNP and the Parkway would not be expected to change, although modes of

travel to those resources would change.

Effects on Visitor Experience — Yellowstone National Park

The amount and type of winter visitor opportunities offered in the YNP under alternative

E are provided in Table 120.

Table 120. YNP Visitor opportunities available under alternative E.

Opportunities

Miles or

Areas

Increase/

Decrease† Length of Season Other

 Groomed motorized route 184 0 Mid-December

to Mid-March

Groomed motorized route,

snowcoach only

0 0 Mid-December

to Mid-March

Groomed motorized trail 0 0 Mid-December

to Mid-March

Plowed route 76 0 Mid-December

to Mid-March

Groomed nonmotorized 37 0 Mid-December

to Mid-March

Warming huts 6 0 Mid-December

to Mid-March

Backcountry 2.2

million

acres

Restricted

access in

~700,000

acres

Travel restricted

to trails in

important

wildlife winter

range

If scientific

studies and

monitoring of

winter visitor use

and wildlife

indicate that

human use or

activities have a

detrimental effect

on wildlife that

cannot be

mitigated, sections

of road and/or

trails could be

closed.

†

If scientific studies and monitoring of winter visitor use and wildlife indicate that human use or activities have a

detrimental effect on wildlife that cannot be mitigated, sections of road and/or trails could be closed.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

372

Visitor Satisfaction and Experience

Opportunities to view wildlife. Same as alternative D, except if scientific studies and

monitoring related to winter wildlife and winter visitor use indicate that human presence

or activities have a detrimental effect on wildlife or other park values that could not

otherwise be mitigated, certain sections of roads or trails would be closed. The

opportunity to view wildlife would be eliminated in areas recommended for closure.

Opportunities to view scenery. Same as alternative D, except if scientific studies and

monitoring related to winter wildlife or other park values indicate that human presence or

activities have a detrimental effect on wildlife that could not otherwise be mitigated,

certain sections of roads or trails would be closed. The opportunity to view scenery

would be eliminated in areas recommended for closure.

Safety (the safe behavior of others). Same as alternative A.

Quality of the groomed surface. Same as alternative A

The availability of access to winter activities or experiences. Backcountry users are

restricted to designated routes in important winter range. This action would limit the

range of opportunities currently available to skiers.

If scientific studies and monitoring related to winter wildlife and other park values

indicate that human presence or activities have a detrimental effect on wildlife that could

not otherwise be mitigated, certain sections of roads or trails would be closed.

Recommended closures would, in the short term, eliminate access to the winter

experience in those areas.

Availability of information. Same as alternative A.

Quiet and Solitude. Because use in important wildlife winter range is restricted to

designated trails, skiers may find fewer opportunities to experience solitude.

Under alternative E oversnow vehicle sound standards would be established by an

advisory committee. These standards would be implemented at various levels over the

next 10 years. While the short-term beneficial changes in visitor experience would be

minor, the long-term goal of reducing snowmobile emissions would enhance the ability

to experience quiet in YNP.

Clean air. Under alternative E oversnow vehicle emission standards would be

established by an advisory committee. These standards would be implemented at various

levels over the next 10 years. While the short-term beneficial changes in visitor

experience would be minor, the long-term goal of reducing snowmobile sound emissions

would moderately enhance the ability to experience clean air in YNP.
IMPACTS OF IMPLEMENTING ALTERNATIVE E

373

Conclusion

The adaptive management provisions of this alternative require that if scientific studies

on winter visitor use, natural resources, and other park values indicate that sections of the

park must be closed to protect those values. All visitor experiences currently afforded in

the closure area would be eliminated. These closure areas would result in direct major

adverse impacts on desired winter visitor experience. However, long-term resource

protection would provide major benefits to the protection of these experiences park-wide.

Negligible to moderate beneficial short-term improvements in opportunities to appreciate

clean air, quiet, and solitude are expected from the implementation of the standards set by

the advisory committee.

Effects on Visitor Experience — Grand Teton National Park and the

Parkway

The amount and type of winter visitor opportunities offered in GTNP under alternative E

are provided in Table 121.

Table 121. GTNP Visitor opportunities available under alternative E.

Opportunities

Miles

or

Areas

Increase/

Decrease Length of Season Other

Groomed motorized route 2.1 0 December to April† Nighttime speed limit

35 mph

Groomed motorized route,

snowcoach

2.1 0 December to April† Nighttime speed limit

35 mph

Groomed motorized trail 8 -26 December to April† Nighttime speed limit

35 mph

Plowed road 94.4 -5.6 December to April† Nighttime speed limit

35 mph

Ungroomed motorized

trail or area

0 -35.6 December to April† Nighttime speed limit

35 mph

Groomed nonmotorized 0 0 December to April† Nighttime speed limit

35 mph

Ungroomed nonmotorized

trail or area

35 8.6 December to April† Nighttime speed limit

35 mph

Warming huts/interpretive

centers

2 0 December to April†

† Variable, dependent on snow conditions.

Visitor Satisfaction and Experience

Opportunities to view wildlife and scenery. There would be decreased opportunities to

view wildlife and scenery via snowmobile. Opportunities would be available in the same

areas by auto.

Safety (the safe behavior of others). Since the CDST would be eliminated through

GTNP, any potential for motor vehicle accidents involving oversnow use of this route
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

374

also would be eliminated. The nighttime speed limit would improve safety where

motorized oversnow use occurs.

Quality of the groomed surface. Grassy Lake Trail would be groomed at its present

level. There would be no nonmotorized trail grooming.

The availability of access to winter activities or experiences. There would be

decreased oversnow motorized access, and no oversnow linkage via CDST between trail

systems to the east and YNP. Elimination of motorized use on the frozen surface of

Jackson Lake would decrease the range of experiences available. A secondary impact

would be loss of motorized access onto Jackson Lake for ice fishing. This opportunity

would remain available for those who would use the lake surface via nonmotorized

means. The loss of motorized experience on the lake would be countered by a gain in

nonmotorized opportunities free of any use conflict that might ordinarily occur.

Availability of information. Same as in alternative A.

Quiet and Solitude. With the elimination of motorized use, except for Grassy Lake

Trail and access north from Flagg Ranch, opportunities for quiet and solitude would be

moderately enhanced for nonmotorized uses.

Clean air. With the decrease in motorized use, except for Grassy Lake Road, the major

source of pollution would be eliminated.

Conclusion

Minor adverse impacts to visitor experience would occur due to fewer opportunities to

view wildlife and scenery by snowmobile. The same opportunity remains for

nonmotorized users and automobile occupants. There would be major beneficial changes

relating to safety by eliminating snowmachines as a source of motor vehicle accidents,

except on Grassy Lake Road. There would be a major adverse impact on the availability

of groomed surfaces for snow-related recreation, and consequently a major adverse

impact on access for a range of winter use experiences. The level and availability of

winter information would not be improved from the existing condition. There would be a

moderate beneficial impact relative to opportunities for quiet and solitude, other than for

those who use motorized means. Opportunities to appreciate clean air would be

moderately improved due to the elimination of the major source of pollution. Where

oversnow motorized use remains, opportunities to experience quiet and clean air would

be afforded by use of improved motorized technology.

IMPACTS OF IMPLEMENTING ALTERNATIVE F

Unless otherwise indicated, the effects of this alternative for GTNP and the Parkway are

the same as indicated in alternative E. The actions proposed for GTNP and the Parkway

are the same in alternatives E and F. Because YNP actions differ between these

alternatives, some effects on GTNP may be different as noted in the following analysis.
IMPACTS OF IMPLEMENTING ALTERNATIVE F

375

Effects on the Socioeconomic Environment

GYA Regional Economy. Alternative F contains several provisions for relatively minor

changes in trails management within YNP. Most of these changes are unlikely to

significantly impact visitor decisions on whether to visit the parks for recreation. One

proposed management change, however, has the potential to significantly impact

visitation levels to the GYA and consequently, visitor expenditures and the overall level

of economic activity within the GYA. Alternative F contains a proposal to close the

western side of YNP to all winter travel.

The 1999 GYA winter visitor survey asked respondents how their visitation would be

affected if the roads from Mammoth to Madison, West Yellowstone to Madison, and

Madison to Old Faithful were closed to all vehicular travel from November 1 to April 30,

and other roads were groomed for snowmobiles as they are now. Based on the responses

to this survey question, visitation to the GYA by winter visitors who live outside the five

counties would be reduced by 24.6% if the roads from Mammoth to West Yellowstone

and to Old Faithful were closed for winter travel. It is likely that this estimate of use

reduction is conservative since the question in the winter survey specified a road closure

for vehicles only. To the extent that skiers and snowshoe visitors would also reduce their

park visitation under this alternative, these estimates of impacts are conservative. This

estimated reduction in visitation is a net change that considers the responses of those

current winter visitors who said they would visit more often if the change occurred. Also

considered in the calculation were those respondents who said they would visit the same,

but would shift their use to other areas of the GYA (for example, from park lands to

national forest lands).

Park visitors who reside outside the five counties made up 85.9% of total sampled

visitors. If 24.6% of these visitors decided not to recreate within the GYA because of the

west side road closure within the park, the local GYA economy would lose these

potential visitors’ local-area expenditures.

Based on the winter survey responses and the IMPLAN input/output model, these travel

restrictions would reduce the total economic output in the five-county GYA area by an

estimated $14.4 million. In addition it is estimated that 340 jobs within the five-county

area would be lost due to reduced nonresident expenditures in the area.

A $14.4 million loss in output is a minor impact on the overall $5.7 billion economic

output of the GYA. This impact, however, likely will be concentrated in small

communities such as West Yellowstone and Gardiner, Montana. Because of the small

size their economies, and proximity to the affected road segments, it can be assumed that

these towns will bear a disproportionately large share of the nonresident expenditure

reductions. This could have a moderate to major negative impact on the West

Yellowstone and Gardiner winter economies.

The socioeconomic effects of alternative F for GTNP and the Parkway generally would

be the same as alternative E. With the closure of the west side roads in YNP, some use
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

376

could shift to the Flagg Ranch area. The amount of such a shift is not quantifiable;

however, visitor expenditures also would shift with use. Use levels would be limited at

both these locations because of the amount of parking that is available. A moderate

increase in visitor expenditures in the Jackson area may result from this shift. At other

entrances, such as East and Mammoth in YNP, minor increases in use also may occur,

bringing commensurate increases in visitor expenditures to communities such as Cody,

Wyoming and Gardiner and Cooke City, Montana.

Three-State Regional Economy. Overall, 65.5% of winter visitors in the GYA winter

visitor survey came from outside the three-state area. Responses from nonresidents

indicate that there would be a 20.2% drop of nonresident winter trips to the GYA under

alternative F.

A loss of the regional expenditures by these nonresidents would lead to an overall

reduction of $13.7 million in total economic output and 334 jobs in the three-state area.

This is a negligible to minor negative impact in the context of the regional three-state

economy. This estimated reduction would be lessened if nonresidents chose to recreate

at other locations within the three-state region instead of in the GYA. The extent of any

such substitution behavior is unknown.

Minority and Low-Income Populations. To the extent that convenient, low-cost access

is reduced by the closure of west side roads within YNP, populations living near West or

East Entrances to YNP would be adversely impacted. The degree of this impact, if any,

is not known at this time.

Social Values. Most current winter visitors surveyed support mechanized access to the

parks. In the context of overall park access, the changes proposed in alternative F are

likely to result in major adverse impacts by eliminating some of the most heavily used

winter motorized routes within the parks. Conversely, a substantial portion of winter

park users favor reductions in motorized use within the park. For this group the

alternative F travel restrictions would have a positive impact.

Nonmarket Values. The proposed alternative F actions potentially would impact winter

visitors’ nonmarket values through a reduction in current winter user visitation, resulting

from the closure of the west side roads.

The nonmarket value of a trip to the parks, based on the winter visitor survey is $91. It is

estimated that park visitation would drop by 24.6% resulting from the park closure.

Based on current winter visitation levels, a 24.6% reduction in visitation would translate

into a $2 million reduction the aggregate nonmarket value of winter trips to the parks.

This is a moderate negative impact.

Conclusion

Alternative F management actions would have a negligible to minor impact on the fivecounty and three-state economies through reduced visitation and nonresident visitor
IMPACTS OF IMPLEMENTING ALTERNATIVE F

377

expenditures. The reduced visitor expenditures under this alternative could have a larger,

moderate to major adverse impact on the economies of small communities within the

GYA such as West Yellowstone or Gardiner, Montana. The alternative F actions would

also have a moderate negative impact on total current trip nonmarket visitor benefits

(through reduced visitation).

Effects on Air Quality and Public Health

In alternative F the roads from the West Entrance to Madison to Old Faithful would be

closed to emphasize the protection of wildlife. Winter recreation activities would focus

on scenic areas in the eastern and southern portions of YNP.

Table 122, Table 123, and Table 124 summarize the results of CO modeling for six

locations in the three parks for alternative F. Table 122 and Table 123 show the

predicted maximum 1-hour average CO concentrations and the calculated maximum 8-

hour average CO concentrations, respectively. The percent contribution of each vehicle

type to the maximum CO concentrations also is provided in Table 124 for the six

locations. Table 125 and Table 126 provide corresponding model results for PM10 for the

same locations and conditions as those for CO.

Table 122. Maximum 1-hour average CO concentrations for alternative F.

Location

1-hr Maximum

Concentration

(w/o Background)

(ppm)

1-hr Maximum

Concentration

(w/Background)

(ppm)

Change Relative

to Alternative A

(w/o Background)

(%)

West Yellowstone Entrance No Vehicular Traffic

West Entrance to Madison Roadway

Old Faithful Staging Area 1.28 4.28 0.2

Flagg Ranch Staging Area 1.74 4.74 -1.4

Flagg Ranch to Colter Bay Roadway 0.60 3.60 45.5

Mammoth to NE Entrance Roadway 0.30 3.30 0
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

378

Table 123. Maximum 8-hour average CO concentrations for alternative F.

Location

8-hr Maximum

Concentration (w/o

Background)

(ppm)

8-hr Maximum

Concentration

(w/Background)

(ppm)

Change Relative to

Alternative A (w/o

Background) (%)

West Yellowstone Entrance No Vehicular Traffic

West Entrance to Madison Roadway

Old Faithful Staging Area 0.21 1.62 0.2

Flagg Ranch Staging Area 0.29 1.69 -1.4

Flagg Ranch to Colter Bay Roadway 0.28†1.69†45.5

Mammoth to NE Entrance Roadway 0.14†1.55†0

†

 Estimated from the modeled maximum 1-hour average concentration based on the persistence formula

 Ct2 = Ct1*(t1/t2)^0.365 (Cooper and Alley 1990).

Table 124. Vehicle contribution to CO concentrations for alternative F.

Contribution (%)

Location SM SC AM LT HT TB SV

West Yellowstone Entrance

West Entrance to Madison Roadway

No Vehicular Traffic

Old Faithful Staging Area 98.8 1.1 0 0 0.1 0 0

Flagg Ranch Staging Area 79.4 0.8 5.7 11.3 0.1 0 2.8

Flagg Ranch to Colter Bay Roadway 0 0 25.2 59.1 0.3 0.3 15.2

Mammoth to NE Entrance Roadway 0 0 26.5 66.9 0.5 0 6.1

SM = snowmobile, SC = snowcoach, AM = automobile, LT = light truck, HT = heavy truck, TB = tour bus, SV = shuttle

van.

Table 125. Maximum 24-hour average PM10 concentrations for alternative F.

Location

24-hr Maximum

Concentration

(w/o Background)

(μg/m3)

24-hr Maximum

Concentration

(w/Background)

(μg/m3)

Change Relative

to Alternative A

(w/o Background)

(%)

West Yellowstone Entrance No Vehicular Traffic

West Entrance to Madison Roadway

Old Faithful Staging Area 0.64 5.64 0

Flagg Ranch Staging Area 0.71 5.71 -11.6

Flagg Ranch to Colter Bay Roadway 0.32†5.32 66.7

Mammoth to NE Entrance Roadway 0.32†5.32 0

†

 Estimated from the modeled maximum 1-hour average concentration based on the persistence formula

 Ct2 = Ct1*(t1/t2)^0.365 (Cooper and Alley 1990).
IMPACTS OF IMPLEMENTING ALTERNATIVE F

379

Table 126. Vehicle contribution to PM10 concentrations for alternative F.

Contribution (%)

Location SM SC AM LT HT TB SV

West Yellowstone Entrance

West Entrance to Madison Roadway

No Vehicular Traffic

Old Faithful Staging Area 99.6 0 0 0 0.4 0 0

Flagg Ranch Staging Area 99.6 0 0 0 0.3 0.2 0

Flagg Ranch to Colter Bay Roadway 0 0 21.3 41.0 14.8 12.3 10.6

Mammoth to NE Entrance Roadway 0 0 22.5 46.6 26.7 0 4.2

SM = snowmobile, SC = snowcoach, AM = automobile, LT = light truck, HT = heavy truck, TB = tour bus, SV = shuttle

van.

Visibility

The visibility assessment indicates that under this alternative, vehicular emissions would

not cause any perceptible visibility impairment near the West Entrance or along the

roadways. Perceptible visibility degradation could occur near Old Faithful and Flagg

Ranch when vehicles idle for extended periods.

Conclusion

As noted in Table 122, Table 123, and Table 125, the model predicts negligible

beneficial and adverse impacts on CO and PM10levels relative to alternative A at the Old

Faithful staging area and the Flagg Ranch staging area, respectively. No results were

generated for the West Entrance and along the West Entrance to Madison roadway since

there would be no vehicular traffic at these locations. Relative to alternative A, this

represents a major beneficial impact on CO and PM10 concentrations. Moderate and

major beneficial impacts on CO and PM10 concentrations are predicted along the Flagg

Ranch to Colter Bay roadway. These decreased concentrations are attributable to the

prohibition of snowmobiles on this roadway.

Effects on Public Safety

Eliminating oversnow travel from sunset to sunrise would eliminate vehicular incidents

during these times. Within YNP, roadway segments between West Yellowstone and

Madison, Madison and Old Faithful, Madison and Norris, and Norris and Mammoth

would be closed to all vehicle travel from November 1 to April 30. Closing these heavily

used road segments would eliminate the potential for visitor conflicts in these areas. In

the winters of 1995-1999, 71% of all reported snowmobile accidents occurred on these

road segments.

Current road conditions are cited as a contributing factor in about 16% of all reported

snowmobile accidents in YNP. Improved road conditions would thus be expected to

decrease accident rates. Eliminating travel on a freshly groomed route allows the surface

to harden and so improve its quality. Since most road grooming in YNP is performed in
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

380

the early evening, the sunset to sunrise closure would provide moderate improvements to

the groomed surface quality.

Restricting all skiing activities to groomed front country trails would eliminate the risk of

visitor injury or death from avalanche or exposure in backcountry areas in YNP.

Conclusion

Oversnow travel closures at night and on the most congested road segments would result

in major beneficial improvements to public safety in YNP. If these closures should

increase visitation to other areas of the parks, such as the Flagg Ranch to South Entrance

segment (where most snowmobile accidents occur in the parkway at present), then a

corresponding adverse effect on public safety would occur.

In GTNP all alternative F actions are the same as alternative E, with a negligible increase

in beneficial impact due to the overall elimination of nighttime travel.

Effects on Geothermal Features

Under this alternative roads on the east side would be groomed near the following

geothermal areas: West Thumb Geyser Basin, Mud Volcano, and Norris Geyser Basin.

The impacts on these areas from groomed roads would be the same as described in

alternative A.

Constructing a warming hut at Norris Geyser Basin would have similar impacts on this

geothermal area as discussed under alternatives A and B.

There would be minor beneficial impacts on the geothermal resources with a shorter

winter season (mid-December to early March) and a later spring opening in late April,

since there would be less time for visitors to access geothermal features.

Visitors would not be able to access many geothermal areas due to the closures of west

side park roads and the backcountry. These closures would cause major beneficial

improvements to the protection of geothermal features by eliminating human access.

Conclusion

Overall human access would decrease in geothermal areas parkwide due to closures and

shortened winter and spring seasons. This decrease would have major benefits to the

protection of geothermal features in areas where use is eliminated, and minor benefits in

areas with continued use. There may be a minor increase of visitor use to the Norris

Geyser Basin because of a new warming hut. This would cause minor adverse impacts

on the geothermal basin.

Effects on Water and Aquatic Resources

Potential pollution sources are the same as described in alternative A. The potential

impacts along three “high” risk road segments would decrease with the elimination of all
IMPACTS OF IMPLEMENTING ALTERNATIVE F

381

vehicles: Madison to Norris, Madison to Old Faithful, and Colter Bay to Moran Junction

road segments.

Potential impacts along the Canyon Village to Fishing Bridge “high” risk segment are

expected to increase with the projected increase in snowmobile traffic.

Risks along three “medium” risk segments, Mammoth to Norris, West Entrance to

Madison, and Moran Junction to East Entrance, would decrease with the prohibition of

snowmobiles or all vehicles. Risks would increase along four “medium” risk segments:

Fishing Bridge to East Entrance, Fishing Bridge to West Thumb, Old Faithful to West

Thumb, and West Thumb to Flagg Ranch.

Risk to the “low” risk segment Norris to Canyon and Flagg Ranch would be decreased

with the prohibition of snowmobiles. Risk to the “low” risk segment Flagg Ranch to

Colter Bay, Teton Park Road, and Moose-Wilson Road, would be decreased with the

elimination of all vehicles.

There would be no change along all other road segments.

Conclusion

Two-stroke engine emissions would continue to deposit pollution into snowpack along

groomed park roads in YNP and GTNP. The effect of this deposition on water quality is

undetermined, but there is currently no evidence of measurable changes in water quality

or effects on aquatic resources. It is possible that accumulations of pollutants in aquatic

systems may have adverse impacts on wetlands and aquatic resources downstream from

high risk road segments. Oversnow vehicle use in this alternative involves localized high

risk to surface water quality. However, it reduces oversnow vehicle-miles traveled along

high risk road segments in the three park units by about 74%. The risk of moderate to

major adverse impacts on water quality in Jackson Lake would be eliminated.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

382

Table 12741. Snowmachines and associated risk levels for alternative F.

Impact: Daily Vehicle

Miles Traveled Along

the Segment in Alt. A †

Impact: Daily Vehicle

Miles Traveled Along

the Segment in Alt. F †

Road Segment

Risk ±

Rating SM SC SM SC

Mammoth to Norris Medium 641 69 0 0

West Entrance to Madison Medium 7759 127 0 0

Madison to Norris High 3458 73 0 0

Norris to Canyon Village Low 2214 47 1200 36

Canyon Village to Fishing Bridge High 2370 50 3472 48

Fishing Bridge to East Entrance Medium 983 0 2079 0

Fishing Bridge to West Thumb Medium 2627 55 5019 63

Madison to Old Faithful High 7818 165 0 0

Old Faithful to West Thumb Medium 3560 73 5831 68

West Thumb to Flagg Ranch Medium 4219 103 8976 96

Grassy Lake Road High 184 0 200 0

Flagg Ranch to Colter Bay Low 379 0 0 0

Colter Bay to Moran Junction High 248 0 0 0

Moran Junction to East Entrance Medium 49 0 0 0

Teton Park Road Low 156 0 0 0

Moose-Wilson Road Low 6 0 6 0

Mitigation

Best management practices would be used during the construction, reconstruction, or

winter plowing of trails and roads to prevent unnecessary vegetation removal, erosion,

and sedimentation. The release of snowpack contaminants into surface water could be

mitigated by disconnecting snowmelt drainages from trails used by oversnow vehicles.

Any new or reconstructed winter use sanitary facilities would be constructed in locations

and use advanced technologies that would protect water resources. A focused program of

monitoring would reduce the uncertainty of impacts from oversnow vehicles, and if

necessary, indicate best management practices that might be implemented.

Effects on Wildlife

The impacts disclosed below apply to YNP. For GTNP and the Parkway, all actions and

impacts associated with this alternative are the same as in alternative E, with the

exception of recommended mitigation that closes Blacktail Butte and Wolff Ridge to

protect moose, bison, and elk in important winter range in the park.

 

41 *SM = Snowmobile, SC = Snowcoach; The source of pollutants is emissions from snowmobiles, which

produce (conservatively) 10 times as many emissions per mile as most wheeled vehicles. Single

snowcoaches produce fewer emissions than single snowmobiles.

±High = within 100 meters of aquatic system on 76-100% of the road segment; Medium = within 100 on 51-

75% of the road segment; Low risk segments are within 100 meters of rivers less than 50%.
IMPACTS OF IMPLEMENTING ALTERNATIVE F

383

Ungulates

Effects of groomed roads and trails. Packed trails may influence wildlife movements

and distributions by facilitating travel into areas that would normally be inaccessible due

to deep snow. Under this alternative YNP would maintain 119 miles of groomed

oversnow motorized routes (a decrease of 65 miles over alternative A), and 27 miles of

groomed nonmotorized routes (a decrease of 10 miles over alternative A). In addition

use of the remaining available surfaces would be discontinued two weeks earlier than

under current management, and oversnow travel would be prohibited from sunset to

sunrise. GTNP would groom 10 miles of oversnow motorized routes (a decrease of 26

miles from alternative A).

In YNP road closure from West Entrance to Old Faithful and Mammoth to Madison

Junction would eliminate all motorized use along those segments and all impacts

associated with those uses. An energy efficient means for bison to move within their

primary habitat and to other locations in and out of the park would be eliminated.

Resulting distribution would depend on snow conditions and how bison naturally

maintain traditional travel routes. Motorized use and its impacts would be eliminated in

the most important ungulate habitats within YNP. The impact reduction would be

proportionately greater than the reduction in miles. Consequently, the potential effects

associated with this use, compared to those in alternative A, would decrease greatly.

Effects of motorized oversnow use of groomed and ungroomed roads and trails. The

use of motorized oversnow vehicles can cause displacement from preferred habitats and

injury and death for wildlife, especially in poor lighting conditions and during snowfall.

Fewer wildlife-snowmobile collisions would occur because there would be 65 fewer

miles of travel surface in YNP and 62 fewer in GTNP. Closures would occur where most

collisions presently occur (Gunther et al. 1998), and there would be a prohibition on

travel during times when most collisions occur (dusk to dawn). The potential for impacts

on ungulates would be eliminated throughout the entire western portion of the park,

including the elimination of barriers to movement (fragmentation) and displacement

effects. If significant numbers of snowmobiles were displaced to the east side of YNP,

there could potentially be more of an impact to bison that are wintering there.

With the closures in important habitat, shortening of the winter use season, and

prohibition of oversnow travel from dusk to dawn, the overall effect in YNP would be

reduced to negligible and short term in this alternative.

Effects of plowed roads. Road plowing may cause habitat fragmentation by creating

structural barriers (i.e., snow berms) to ungulate movements (Aune 1981). In addition

plowed roads, like groomed roads, may also provide an energy efficient mechanism for

wildlife movements, including bison, elk, and moose. Under alternative F YNP would

plow 76 miles of road for wheeled-vehicle access in the winter, the same as under current

management. GTNP would plow 94 miles, 6 miles less than now.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

384

For both parks, the effects associated with plowed roads would be the same as alternative

A.

Effects of motorized use of plowed roads. The effects of plowed roads are similar to

those of groomed roads, except that the magnitude of the effect is usually greater. The

use of motorized vehicles on plowed roads can cause displacement from preferred

habitats and injury and death to wildlife, especially in poor lighting conditions, at dusk

and dawn, and during snowfall.

Effects of plowed roads would be essentially the same as alternative A.

Effects of nonmotorized use of groomed and designated ungroomed routes. The

primary effects of nonmotorized use on ungulates are displacement from preferred

habitats, especially geothermal areas that are important for winter survival in YNP, and

increased energy expenditures, including physiological stress, which may reduce

individuals’ chances of survival. In this alternative YNP decreases these opportunities

from 37 miles to 27 miles of groomed nonmotorized routes. GTNP adds 8 miles of

nonmotorized route.

Overall, any adverse effect of this use is negligible. Minor site-specific impacts are

possible where trails occur in or near thermal areas. Decreasing these opportunities

decreases the potential for adverse impacts associated with them. However, the potential

for impact is relatively low because most trails and routes are located in areas not

presently used or preferred by ungulates.

Effects of unregulated backcountry nonmotorized use. Unregulated backcountry

nonmotorized use is more random and infrequent than nonmotorized use on designated

routes. Although encounters between backcountry users and ungulates may only occur

sporadically, they can be especially disturbing and lead to additional energy expenditure

and stress that reduces animals’ chances of survival and reproduction.

For YNP this alternative restricts nonmotorized use to front country trails. All

backcountry use is prohibited, thereby eliminating any potential effects associated with

this activity and greatly decreasing effects relative to alternative A. In GTNP mitigation

is recommended to prohibit public access to Blacktail Butte, Wolff Ridge, and bighorn

sheep winter ranges.

Effects of the presence and use of winter support facilities. Increases in human

activity associated with the presence of support facilities may displace species sensitive

to human disturbance. Alternative F proposes to increase the number and size of

warming huts. Warming huts and restrooms would be located at popular ski trailheads,

motorized staging areas, and areas where existing facility size is currently inadequate or

nonexistent (e.g., Tower, Norris, and Canyon). Warming huts near ungulate winter range

important to elk, deer, and bison would potentially increase human use and consequently

reduce habitat effectiveness. However over time, the predictable nature of the recreation
IMPACTS OF IMPLEMENTING ALTERNATIVE F

385

expected to occur in the area may allow species to habituate to increased human activity.

The effects of these huts on ungulates would be the same for all alternatives.

Federally Protected Species

Effects of groomed roads and trails. Packed trails may influence wildlife movements

and distributions by facilitating travel into areas that would normally be inaccessible due

to deep snow. Under this alternative YNP would maintain 119 miles of groomed

oversnow motorized routes (a decrease of 65 miles over alternative A), and 27 miles of

groomed nonmotorized routes (a decrease of 10 miles over alternative A). In addition

use of the remaining available surfaces would be discontinued two weeks earlier than

under current management, and oversnow travel would be prohibited from sunset to

sunrise. GTNP would groom 10 miles of oversnow motorized routes (a decrease of 26

miles from alternative A).

Impacts are generally as stated in alternative A — none to negligible, but may be slightly

reduced. If federally protected species activity is known to occur in an area, park

managers can close the area to human activity to mitigate disturbance.

Effects of motorized use of groomed and ungroomed roads and trails. The use of

motorized oversnow vehicles can cause displacement from preferred habitats. Collision

impacts from snowmobiles and snowcoaches have not been documented for any of the

federally protected species in the parks. Collisions would be even less likely under this

alternative because there would be 65 fewer miles of travel surface in YNP and 62 fewer

in GTNP. Also there would be a prohibition on travel during the times when animals are

most active.

Road closure from the West Entrance to Old Faithful and Mammoth to Madison Junction

would eliminate all motorized use along those segments and all impacts associated with

them. The potential for impacts on federally protected species would be eliminated on

the closed sections, including the elimination of barriers to movement (fragmentation)

and displacement effects. Suitable habitat throughout the entire western portion of the

park would be available for free movement of species active in the winter. The

termination of the winter season after March 1 would minimize the potential for bearhuman confrontations, and conflicts that could occur after grizzly bear emergence during

spring.

Impacts are generally as stated in alternative A — none to negligible, but may be slightly

reduced. If federally protected species activity is known to occur in an area, park

managers can close the area to human activity to mitigate disturbance.

Effects of plowed roads. Road plowing may cause habitat fragmentation by creating

structural barriers (i.e., snow berms) to wildlife movements (Aune 1981). In addition

similar to groomed roads, plowed roads may influence wildlife movements and

distributions by facilitating travel into areas that would normally be inaccessible due to
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

386

deep snow. Under alternative F YNP would plow 76 miles of road for wheeled-vehicle

access in the winter, the same as under current management. GTNP would plow 94

miles, 6 less than currently.

For YNP the effects associated with plowed roads would be the same as alternative A. If

federally protected species activity is known to occur in an area, park managers can close

the area to human activity to mitigate disturbance.

Effects of motorized use of plowed roads. The effects of traffic on plowed roads are

similar to those of traffic on groomed roads, except that the magnitude of the effect is

usually greater. The use of motorized vehicles on plowed roads could cause

displacement from preferred habitats and injury and death to wildlife, especially in poor

lighting conditions, at dusk and dawn, and during snowfall.

Impacts are generally as stated in alternative A – none to minor. If threatened and

endangered species activity is known to occur in an area, park managers can close the

area to human activity to prevent disturbance.

Effects of nonmotorized use on groomed and designated ungroomed routes. The

primary effects of nonmotorized use on wildlife are displacement from preferred habitats

and increased energy expenditures, including physiological stress, which may reduce

individuals’ chances of survival. In this alternative YNP decreases these opportunities

from 37 miles to 27 miles of groomed nonmotorized routes. GTNP adds 8 miles over

current management. Potential impacts are generally as stated in alternative A — none to

negligible. If protected species activity is detected, park managers could close the area to

human activity to mitigate disturbance.

Effects of unregulated backcountry nonmotorized use. Unregulated backcountry

nonmotorized use is more random and infrequent relative to nonmotorized use on

designated routes. Although encounters between backcountry users and federally

protected wildlife species may occur sporadically, they may cause displacement and

additional energy expenditure and stress that reduces animals’ chances of survival and

reproduction. For YNP this alternative restricts nonmotorized use to front country trails

thereby eliminating any potential effects associated with this activity.

Presence and use of winter support facilities. Warming huts and campgrounds can

cause habituation in some wildlife species by the presence of human food and garbage,

and can lead to human-wildlife conflicts. In addition increases in human activity

associated with the presence of support facilities may displace species sensitive to human

disturbance. Alternative F proposes to increase the number and size of warming huts in

YNP. Warming huts and restrooms would be located at popular ski trailheads, motorized

staging areas, and areas where existing facility size is currently inadequate or nonexistent

(e.g., Tower, Norris, and Canyon).
IMPACTS OF IMPLEMENTING ALTERNATIVE F

387

Potential impacts are generally as stated in alternative A — none to minor. If federally

protected species activity is known to occur in an area, park managers can close the area

to human activity to mitigate disturbance. Construction of winter wildlife-proof garbage

facilities at all major winter destination areas (a feature of all alternatives) would mitigate

problems associated with habituated wildlife, including grizzly bears.

Species of Special Concern

Effects of groomed roads and trails. Packed trails may influence wildlife movements

and distributions by facilitating travel into areas that would normally be inaccessible due

to deep snow, inhibiting foraging activities of carnivores that tunnel beneath the snow to

hunt subnivian prey, and reducing subnivian prey availability by increasing mortality of

these small mammals. Under this alternative YNP would maintain 119 miles of groomed

oversnow motorized routes (a decrease of 65 miles over alternative A) and 27 miles of

groomed nonmotorized routes (a decrease of 10 miles over alternative A). In addition

use of the remaining available surfaces would be discontinued two weeks earlier than

under current management, and oversnow travel would be prohibited from sunset to

sunrise. GTNP would groom 10 miles of oversnow motorized routes (a decrease of 26

miles from alternative A).

Impacts are generally as stated in alternative A — none to negligible, but may decrease

slightly.

Effects of motorized oversnow use of groomed and ungroomed roads and trails. The

most likely impacts to park species of special concern are displacement from preferred

habitats, and degradation of the aquatic environment from pollutants in the snowpack.

Documented mortality caused by collisions with oversnow vehicles in the parks is rare.

In 10 years only one of these species (a marten) was reportedly killed by a snowmobile in

YNP (Gunther et al. 1998). Collision impacts would be even less likely under this

alternative because there would be 65 fewer miles of travel surface in YNP and 62 fewer

in GTNP. Closures would occur where most of the collisions presently occur, and there

would be a prohibition on travel during times that most collisions occur.

Impacts are generally as stated in alternative A — none to minor.

If species activity is known to occur in an area, park managers can close the area to

human activity to mitigate disturbance. In YNP prohibition of travel from sunset to

sunrise would mitigate the possible impact of vehicle collisions during times when they

are more likely to occur. Road closure from West Entrance to Old Faithful and

Mammoth to Madison Junction would eliminate all motorized use along those segments

and all impacts associated with those uses. The potential for impacts on species of

special concern would be eliminated on the closed sections, including the elimination of

barriers to movement (fragmentation) and displacement effects. Suitable and effective

habitat throughout the entire western portion of the park would be available for species
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

388

active in the winter. Known habitat for trumpeter swans along the Madison River would

not be subject to impacts of use along the corridor.

See Water and Aquatic Resources, Chapter IV for an assessment of the impacts of

exhaust on aquatic resources in the parks.

Effects of plowed roads. Similar to groomed roads, plowed roads also provide an

energy efficient mechanism for wildlife movements. Under alternative F, YNP would

plow 76 miles of road for wheeled-vehicle access in the winter, the same as under current

management. GTNP would plow 94 miles, 6 less than currently.

Impacts are generally as stated in alternative A.

Effects of motorized use of plowed roads. The most likely impact to species of special

concern would be displacement from preferred habitats and mortality caused by

collisions with wheeled-vehicles.

Impacts are generally as stated in alternative A — none to negligible. If species activity

is known to occur in an area, park managers can close the area to human activity to

mitigate disturbance.

Effects of nonmotorized use on groomed and ungroomed designated routes. The

primary effects of nonmotorized use are displacement from preferred habitats, and

increased energy expenditures, including physiological stress, which may reduce

individuals’ chances of survival. In this alternative YNP decreases these opportunities

from 37 miles to 27 miles of groomed nonmotorized routes. GTNP would add 8 miles

over current management.

Potential impacts are generally as stated in alternative A — none to minor. If protected

species activity is known to occur in an area, park managers can close the area to human

activity to mitigate disturbance. Groomed trails are not located swan habitat; therefore,

no effects on swans would occur.

Unregulated backcountry nonmotorized use. Unregulated backcountry nonmotorized

use is more random and infrequent than nonmotorized use on designated routes.

Although encounters between backcountry users and species of special management

concern may only occur sporadically, they can be especially disturbing and lead to

additional energy expenditure and stress that reduces animals’ chances of survival and

reproduction. For YNP this alternative restricts nonmotorized use to front country trails

thereby eliminating any potential effects associated with this activity.

Presence and use of winter support facilities. The primary effects of warming huts and

campgrounds on park species of special concern are associated with increases in human

activity and the subsequent disturbance and displacement of species or their prey.

Alternative F proposes to increase the number and size of warming huts. Warming huts

and restrooms would be located at popular ski trailheads, motorized staging areas, and
IMPACTS OF IMPLEMENTING ALTERNATIVE F

389

areas where existing facility size is currently inadequate or nonexistent (e.g., Tower,

Norris, and Canyon).

Compared to current management, impacts related to displacement would be greater due

to the increase in number of facilities. Specifically, huts located in thermally influenced

ungulate winter range could displace ungulates, and thus affect bison and elk carcass

availability for wolverines, fishers, and marten. Because ungulates have been known to

habituate to predictable human activities, any displacement most likely would be shortterm. There would be no support facilities in or near swan habitat.

Conclusion

Alternative F emphasizes wildlife protection. Consequently, many of the potential

impacts to wildlife under this alternative are lower in magnitude than alternative A. Most

important winter habitats are outside human-use areas, the winter use season is closed

two weeks earlier than currently, and oversnow motorized travel is restricted from sunset

to sunrise. Roads on the west side of YNP would not be groomed and would be closed to

oversnow motorized use. Consequently, park managers could study how animals use

these routes in the absence of human activity and intervention.

Impacts to populations resulting from winter recreation are neither long-term nor

significant. However, impacts to individual members of the population can be important,

leading to death either directly from collisions or continued harassment, or indirectly

through management actions taken as a response to habituation to human presence and

food. Although concerned about impacts on individuals, the NPS primarily provides for

the protection of native animal populations from management actions (with the exception

of federally protected species). For example, see Chapter II, NPS 77, Natural Resources

Management.

Ungulates

• Effects of groomed roads and trails on animal movements — unknown if and to what

extent beneficial effects outweigh negative effects. Any effects would be greatly decreased

over alternative A due to the elimination of 65 miles of groomed roads in YNP and 26

miles in GTNP.

• Effects of motorized oversnow use of groomed and ungroomed roads and trails on: 1)

mortality caused by collisions – adverse, negligible, and short term (collision impacts are

less for snowmobiles as compared to wheeled-vehicles by a factor of 10, and snowcoach

collisions are rare); and 2) displacement from preferred habitats – adverse, negligible, and

short term. Effects would be greatly decreased over alternative A due to the elimination of

65 miles of groomed roads in YNP and 26 miles in GTNP and the prohibition on nighttime travel.

• Effects of plowed roads on: 1) habitat fragmentation – adverse, minor, and short term; and

2) animal movements – unknown if and to what extent beneficial effects outweigh negative

effects. Effects are generally the same as alternative A.

• Effects of motorized use of plowed roads on: 1) mortality caused by collisions – adverse,

minor, and short term; and 2) displacement from preferred habitats – adverse, moderate,

and long term. Effects are generally the same as alternative A.

• Effects of nonmotorized use of groomed and designated ungroomed routes on displacement

from preferred habitats – adverse, negligible, and short term. Described effect applies to
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

390

YNP, and is decreased relative to alternative A; effects in GTNP would be the same as

alternative E.

• Effects of unregulated backcountry nonmotorized use on displacement from preferred

habitats – no effect in YNP due to the elimination of backcountry use; in GTNP, effects

would be adverse, moderate, and short term (the same as alternative A).

• Effects of the presence and use of winter support facilities on displacement – adverse,

minor, and short term. Effects may be slightly increased over alternative A because there

are more huts proposed.

Federally Protected Species

• Effects of groomed roads and trails on animal movements: 1) bald eagles, grizzly bears,

and wolves — no effect; and 2) lynx – adverse, negligible to major, and short term,

depending upon lynx distribution and abundance in the parks. Effect may decrease as

compared to alternative A because the amount of groomed surface is reduced substantially.

• Effects of motorized oversnow use of groomed and ungroomed roads and trails on

displacement from preferred habitats – adverse, negligible, and short term for all species

excluding the grizzly bear, which will not be active during the winter use season. Effects

may decrease compared to alternative A because the amount of groomed surface use is

substantially reduced, and the closure of the winter season on March 1 would help

minimize potential conflicts with emerged grizzly bears.

• Effects of plowed roads on: 1) habitat fragmentation – no effect on any of the listed

species; and 2) animal movements – no known effect on any of the listed species. Same as

alternative A.

• Effects of motorized use of plowed roads on: 1) mortality caused by collisions – adverse,

negligible, and short term on bald eagles and grizzly bears; adverse, minor, and short term

on wolves; no known effect to date on lynx; and 2) displacement from preferred habitats –

adverse, negligible, and short term on bald eagles, no effect on grizzly bears; no known

effect to date on wolves and lynx. Same as alternative A. The closure of the winter season

on March 1 would help to minimize potential conflicts with emerged grizzly bears.

• Effects of nonmotorized use of groomed and designated ungroomed routes on displacement

from preferred habitats – adverse, negligible, and short term on bald eagles; no effect on

grizzly bears; no known effect to date on wolves and lynx. Generally the same as

alternative A.

• Effects of unregulated backcountry nonmotorized use on displacement from preferred

habitats – no effect in YNP due to the elimination of backcountry use; in GTNP, effects

would generally the same as alternative A — adverse, minor, and short term on bald

eagles; adverse, negligible, and short term on grizzly bears; adverse, minor, and short term

on wolves; no known effect to date on lynx.

• Effects of the presence and use of winter support facilities on displacement – no affect on

bald eagles; adverse, negligible, and short term on grizzly bears, with mitigation; adverse,

minor, and short term on wolves ); effects on lynx would depend on whether or not huts are

located in lynx habitat. Effects may be slightly increased over alternative A because there

are more huts proposed.

Species of Special Concern

• Effects of groomed roads and trails on 1) animal movements – no known effect on

wolverines; adverse, negligible, and short term on fishers and martens; no effect on otters,

swans, reptiles, amphibians, and fish; 2) foraging activities – adverse, negligible, and short

term on marten; no effect on the other species; and 3) subnivian prey availability —

adverse, negligible, and short term on marten; no effect on the other species. Effects may

decrease as compared to alternative A because the amount of groomed surface is

substantially reduced.

• Effects of motorized oversnow use of groomed and ungroomed roads and trails on

displacement – no known effect on wolverine; adverse, negligible, and short term on

fishers and marten; no effect on otters, reptiles, amphibians, and fish; adverse, minor, and
IMPACTS OF IMPLEMENTING ALTERNATIVE F

391

short term on swans. Effect may decrease as compared to alternative A because the

amount of groomed surface use is substantially reduced.

• Effects of plowed roads on animal movements – no known effect on wolverines, fishers,

and martens; no effect on otters, swans, reptiles, amphibians, and fish. Same as alternative

A.

• Effects of motorized use of plowed roads on displacement from preferred habitats: 1)

adverse, negligible, and short term on wolverines, fishers, and martens; no effect on otters,

swans, reptiles, amphibians, and fish; and 2) mortality from collisions — adverse,

negligible, and short term on otters and martens; no effect to date on other species. Same

as alternative A.

• Effects of nonmotorized use of groomed and designated ungroomed routes on displacement

from preferred habitats – no effect on wolverines; no known effect on fishers, martens, and

otters; adverse, minor, and short term on swans; adverse, negligible, and short term on

sagebrush lizard no effect on rubber boa, amphibians, and fish. Generally the same as

alternative A.

• Effects of unregulated backcountry nonmotorized use on displacement from preferred

habitats – no effect in YNP due to the elimination of backcountry use; in GTNP, effects

would generally the same as alternative A – adverse, negligible, short term on wolverines,

sagebrush lizard; no known effect on fishers, martens, otters; adverse, minor, short term on

swans; no effect on rubber boa, amphibians, fish.

• Effects of the presence and use of winter support facilities on displacement of potential

prey (carcass) availability – adverse, minor, and short term on wolverines, fishers, and

martens; no effect on swans, rubber boa, amphibians, and fish; no known effect on otters;

adverse, minor, and short term on sagebrush lizard. Effects may be slightly increased over

alternative A because there are more huts proposed.

Mitigation

• Backcountry monitoring and administration should be implemented in GTNP.

• Close the south and west-facing slopes of Blacktail Butte, from the valley floor to the

summit, and close all aspects of Wolff Ridge. Additional closures could be imposed if

monitoring indicates such a closure is warranted to protect wintering species.

• The monitoring and evaluation of backcountry nonmotorized use in GTNP should be

enhanced and closures to use should be implemented as warranted.

• Ramps or pullouts where moose could exit plowed roads to reduce collisions between

snowmobiles and moose along the CDST would be provided.

• Use of groomed and plowed surfaces by bison and other ungulates would continue to be

monitored.

• Snow track surveys for carnivores (including lynx) on both groomed and ungroomed routes

would be conducted.

• Close important bighorn winter range in the north and south Teton Range.42

 

42 Southern Tetons: (1) in the Prospectors Mt. and Mt. Hunt areas (including peak 10988), all areas

above 3000m (9,900 ft.), and south-facing slopes on Mt. Hunt above 2600m (8,580 ft.); (2) the

slopes of Static Peak above 3300m (10,890 ft.) (does not affect Albright Peak); and (3) the southfacing slopes above 3000m (9900 ft.) along the north side of Avalanche Canyon and the north fork

of Avalanche Canyon.

Northern Tetons: 1) in the Ranger-Doane-Eagles Rest area (including peaks 10,298; 10,881;

10,023; 10,686), all areas above 3,000 m (9,900 ft.), and south-facing slopes of Eagles Rest above

2,600m (8,580 ft.); 2) in the Elk Mt.-Owl Peak area, all areas above 3,000 m (9,900 ft.), and southfacing slopes above 2,600m (8,580 ft.); 3) on Forellen Peak, all areas above 2,800 m (9,240 ft.)

and south-facing slopes above 2,500 m (8,250 ft.); and 4) the ridgecrest and south-facing slopes of

the cliffs at the mouth of Moose Creek (also known as the “Lower Berry Cliffs”) above 2,300 m

(7,590 ft.).
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

392

Effects on Natural Soundscape

Audibility analysis — combined effects of all wheeled and oversnow vehicles

Table 128 presents the acres of park land by road segment where any wheeled or

oversnow vehicle noise would be audible under the two background conditions,

“average” and “quiet,” as defined in the Assumptions and Methodologies section of this

chapter. For each background condition, acreage is presented for three categories of

audibility: 1) audible for any amount of time (labeled “audible at all”); 2) audible for

10% of the time or more; and 3) audible for 50% of the time or more. Appendix M

contains tables with distances to audibility for each segment for each alternative.

Alternative F features no snowplanes or snowmobiles on Jackson Lake, and no oversnow

vehicles elsewhere in GTNP except from Flagg Ranch to YNP and on Grassy Lake Road.

It also features no vehicles of any type on the West Entrance to Madison, Madison to

Norris, Mammoth to Norris, and Madison to Old Faithful segments in YNP.

The results for alternative F show that for the “average” background conditions, wheeled

or oversnow vehicles would be audible to some degree for over 122,000 acres in the three

park units. For over 73,000 of those acres, wheeled or oversnow vehicles would be

audible for at least 10% of the time during the day. For over 27,000 of those acres, they

would be audible for at least half of the time during the day. These acreage totals

increase by 10%, 13%, and 18% for the “quiet” background conditions for the three

audibility categories, respectively.

The segment from Moran Junction to the South Entrance of GTNP, which carries a great

deal of wheeled-vehicle traffic unrelated to the alternatives, contributes the greatest to the

total acreage values for all three audibility categories. These amounts remain almost

constant for all of the alternatives.

The plowed road from Mammoth to the YNP Northeast Entrance is a major contributor

to the “audible at all” acreage (and, to a lesser extent, “audible 10% or more”), which

remains virtually unchanged across all of the alternatives.

The YNP segments from West Thumb to Flagg Ranch, Fishing Bridge to West Thumb,

Old Faithful to West Thumb, and Canyon Village to Fishing Bridge are also major

contributors to the total acreage for all three audibility categories. The audibility acreage

is reduced to zero for the West Entrance to Madison, Madison to Norris, Mammoth to

Norris, and Madison to Old Faithful segments in YNP. For YNP as a whole, the 50%

time audible acreage increases by 35% over the no action alternative for average

background conditions, due to increased snowmobile volumes on the segments where

they are permitted.

The audibility acreage is reduced to zero for Jackson Lake and Teton Park Road in

GTNP. There are only slight reductions for the Moran Junction to Colter Bay and Flagg

Ranch to Colter Bay segments compared to the no action alternative.
IMPACTS OF IMPLEMENTING ALTERNATIVE F

393

Table 128. Acres of park land affected by vehicle audibility for alternative F.

With Average Background

Conditions

With Quiet Background

Conditions

Road Segment Miles

Audible

at All

Audible

10% of the

Time or

More

Audible

50% of the

Time or

More

Audible

at All

Audible

10% of the

Time or

More

Audible

50% of the

Time or

More

1. Mammoth to Northeast Entrance 47 16,126 5,445 0 16,822 6,342 0

2. Mammoth to Norris 21 No Veh. No Veh. No Veh. No Veh. No Veh. No Veh.

3. West Entrance to Madison 14 No Veh. No Veh. No Veh. No Veh. No Veh. No Veh.

4. Madison to Norris 14 No Veh. No Veh. No Veh. No Veh. No Veh. No Veh.

5. Norris to Canyon Village 12 5,425 3,410 0 5,662 3,828 0

6. Canyon Village to Fishing Bridge 16 10,462 7,726 1,983 11,377 8,525 2,301

7. Fishing Bridge to East Entrance 27 12,743 5,855 0 13,800 7,092 0

8. Fishing Bridge to West Thumb 21 16,888 12,666 4,944 18,687 13,960 5,908

9. Madison to Old Faithful 16 No Veh. No Veh. No Veh. No Veh. No Veh. No Veh.

10. Old Faithful to West Thumb 17 8,012 6,616 2,856 9,513 7,252 4,083

11. West Thumb to Flagg Ranch 24 13,839 11,334 6,165 16,104 12,574 7,985

12. Grassy Lake Road 7.6 3,033 0 0 3,303 0 0

13. Flagg Ranch to Colter Bay 15.6 7,659 2,822 0 8,315 3,103 0

14. Colter Bay to Moran Junction 10.2 4,607 2,239 0 4,956 2,431 0

15. Moran Junction to East Entrance 2 1,199 714 481 1,300 795 525

16. Moran Junction to South Entrance 26 21,714 14,812 11,293 23,842 17,207 11,996

17. Teton Park Road 15 No Veh. No Veh. No Veh. No Veh. No Veh. No Veh.

18. Moose-Wilson Road 2.5 659 0 0 695 0 0

19. Antelope Flats Snowmobile Route 30 No Veh. No Veh. No Veh. No Veh. No Veh. No Veh.

20. Jackson Lake 9.7 No Veh. No Veh. No Veh. No Veh. No Veh. No Veh.

TOTAL 122,364 73,636 27,722 134,377 83,110 32,799

Average sound level analysis

To give a sense of the effect of the number of oversnow or wheeled-vehicles on a road

segment, and their speed and sound level, Table 129 shows the computed hourly

equivalent or “average” sound level (Leq) over the daytime period. Levels are shown for

each road segment at two distances, 100 feet and 4,000 feet, and for both open and

forested terrain. These hourly Leq values do not have the background sound level added

in to them. Also they cannot be compared against the background levels to assess

audibility, since Leq represents a long-term average of both quiet and loud moments.

The hourly Leq at 100 feet are highest for the four above-mentioned YNP road segments.

At 4,000 feet away, the Leq are highest for these four segments, as well as the segments

from Moran Junction to both the East Entrance and the South Entrance of GTNP. The

contribution to the Leq is reduced to zero for the West Entrance to Madison, Madison to

Norris, Mammoth to Norris, and Madison to Old Faithful segments in YNP, and Jackson
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

394

Lake and Teton Park Road in GTNP. There is also a 6 dB reduction along the Flagg

Ranch to Colter Bay segment.

Table 129. Average hourly Leq from wheeled and oversnow vehicle noise at two distances

to each road segment for alternative F.

Leq at distance (dBA)

Open Terrain Forested Terrain

Road Segment 100 feet 4,000 feet 100 feet 4,000 feet

1. Mammoth to Northeast Entrance 35 2 33 0

2. Mammoth to Norris No Veh. No Veh. No Veh. No Veh.

3. West Entrance to Madison No Veh. No Veh. No Veh. No Veh.

4. Madison to Norris No Veh. No Veh. No Veh. No Veh.

5. Norris to Canyon Village 49 9 47 1

6. Canyon Village to Fishing Bridge 52 12 50 4

7. Fishing Bridge to East Entrance 48 7 46 0

8. Fishing Bridge to West Thumb 53 12 51 4

9. Madison to Old Faithful No Veh. No Veh. No Veh. No Veh.

10. Old Faithful to West Thumb 54 14 52 6

11. West Thumb to Flagg Ranch 54 14 53 6

12. Grassy Lake Road 42 2 41 0

13. Flagg Ranch to Colter Bay 38 5 36 0

14. Colter Bay to Moran Junction 40 8 39 0

15. Moran Junction to East Entrance 45 12 43 4

16. Moran Junction to South Entrance 46 14 44 6

17. Teton Park Road No Veh. No Veh. No Veh. No Veh.

18. Moose-Wilson Road 24 0 22 0

19. Antelope Flats Snowmobile Route No Veh. No Veh. No Veh. No Veh.

20. Jackson Lake No Veh. No Veh. No Veh. No Veh.

Conclusion

Alternative F impacts only about 68% of the acreage impacted by the no action

alternative for the “audible at all” categories, nearly as low as alternative D. Alternative

F impacts about 78% of the no action acreage for the “audible 10% of the time or more”

categories, which is the third lowest amount among the alternatives. The reason for the

decreases for these two sets of categories is the elimination of oversnow vehicles on six

road segments in YNP and GTNP, plus Jackson Lake.

However, for the “audible 50% or more” categories, alternative F impacts 118% and

124% of the acreage for the no action alternative for “average” and “quiet” backgrounds,

respectively. These increases are the highest of any of the alternatives. They are due to

large amounts of acreage being added for the West Thumb to Flagg Ranch, Fishing

Bridge to West Thumb, Old Faithful to West Thumb, and Canyon Village to Fishing
IMPACTS OF IMPLEMENTING ALTERNATIVE F

395

Bridge segments, which more than compensate for the eliminated acreage for the

segments on which vehicles would be banned.

The contribution to the Leq is reduced to zero for those road segments where vehicular

travel of all types is eliminated, as well as Jackson Lake.

Effects on Cultural Resources

The effects on cultural resources would be the same as described in alternative B.

Conclusion

None of the actions described would adversely impact cultural resources.

Effects on Visitor Access and Circulation

Access

Yellowstone National Park. Under this alternative roadway segments between

Mammoth and Madison and West Entrance to Old Faithful would be closed. An average

of about 105,500 annual winter use visitors would have to choose whether to use other

entrances or recreate on adjacent federal lands. Current park circulation patterns and

local area access are altered by this alternative. A small number of visitors would no

longer be able to complete the Grand Loop. Snowcoach tours from Mammoth and West

Yellowstone would be eliminated.

Grand Teton National Park and the Parkway. Access and circulation patterns under

alternatives E and F are identical within GTNP and the Parkway. However, as discussed

in alternatives B and C, the closure of YNP’s North and West Entrances in alternative F

may affect GTNP and the Parkway. Access for all types of winter users could shift from

the north and west to the south. Access for the numbers of visitors currently using the

West and North Entrances could greatly increase visitation from the Jackson and Dubois

portals. The staging for oversnow opportunities from these routes would increase the use

of Flagg Ranch or the demand for staging there.

Table 130 depicts a reasonably foreseeable distribution of vehicle use as a consequence

of this alternative. It shows a loss of 87 snowmobile trips daily from the Teton Park

Road and the CDST from GTNP’s East Entrance to Flagg Ranch. There would be a net

change of -35% in snowmobile vehicle-miles traveled in the three park units and a net

increase of 7.6% wheeled-vehicle-miles traveled. Snowcoach miles traveled would

decrease by about 60%.

Table 130. Alternative F motorized use.

Average Daily Vehicle Use January-February

Road Segment Autos Vans Snowcoaches Snowmobiles Buses

Mammoth to Northeast Entrance No change from current condition

Mammoth to Norris 0 0 0 0 0

West Entrance to Madison 0 0 0 0 0

Madison to Norris 0 0 0 0 0
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

396

Norris to Canyon Village 0 0 3 100 0

Canyon Village to Fishing Bridge 0 0 3 217 0

Fishing Bridge to East Entrance 0 0 0 77 0

Fishing Bridge to West Thumb 0 0 3 239 0

Madison to Old Faithful 0 0 0 0 0

Old Faithful to West Thumb 0 0 4 343 0

West Thumb to Flagg Ranch 0 0 4 374 0

Grassy Lake Road No change from current condition

Flagg Ranch to Colter Bay 100 15 0 0 1

 Colter Bay to Moran Junction 200 15 0 0 1

 Moran Junction to East Entrance 580 30 0 0 2

 Moran Junction to South Entrance No change from current condition

 Teton Park Road 0 0 0 0 0

 Moose-Wilson Road 5 0 0 0 0

 Antelope Flats Snowmobile Route No change from current condition

Concession Services

Present concessions affected in this alternative would be those permitted to run oversnow

guided services from West Yellowstone into the park, from Mammoth and Gardiner into

the park, and at Old Faithful. Oversnow guided tours to Old Faithful from both West

Yellowstone and Mammoth/Gardiner would no longer be able to operate because those

entrances to the park interior would be closed. No winter use would be allowed. This

represents the greatest adverse impact on concessions relative to lost business and the

need to completely change the nature of the business or the area in which it operates.

From the perspective of the operation at Old Faithful, the logistics of moving people,

fuel, supplies, or garbage would remain dependent on oversnow transport. Storage of

material in the park’s interior would be the same as now. The difference would be the

need to focus transportation needs of clientele, employees, equipment and supplies

during the winter primarily from the south. This could represent a greater expense for the

concession owner (a service trip from Old Faithful to Jackson would be 93 miles,

oversnow and on the highway, versus 30 oversnow miles to West Yellowstone). The

NPS believes that the Old Faithful experience would be even more attractive under these

circumstances, and that demand for overnight stays would not decline. The time

available under this alternative for business adaptation is two years, when road grooming

would be terminated (winter of 2002-2003).

The implementation of any alternative that might make substantial changes affecting a

concessioner would require negotiation between the NPS and the concessioner or be

deferred until a new concessions contract is pending.
IMPACTS OF IMPLEMENTING ALTERNATIVE F

397

Concessions or services operating at other locations in the parks or from other gateways

would not be affected to any great degree. Current circumstances attractive to

snowmobilers entering the East Entrance to Yellowstone would change in this

alternative. Snowmobilers who enjoy traveling from West Yellowstone to Pahaska

Teepee (or the reverse) to stay overnight would no longer be able to. Instead they would

be able to travel to Old Faithful or Flagg Ranch. This affects a small percentage of use in

the parks, most often on holiday weekends. Pahaska Teepee, permitted as a snowmobile

rental provider, would only marginally be affected because the opportunity to access the

park from this facility remains.

The CDST would be discontinued at the east boundary of GTNP, so snowmobilers

coming into Flagg Ranch over the snow and from the east would no longer be able to do

so. The amount of business actually provided by Flagg Ranch to such users (fuel,

lodging, and groceries) is unknown, but those users are relatively few. Those who

presently engage in this opportunity would have a shuttle system (which could be

concession provided) available to them in this alternative for transport from the east

boundary to Flagg Ranch.

Conclusion

Because two winter entrances into YNP would be eliminated, a substantial number of

winter use visitors would no longer be able to access park resources unless they chose to

travel to other park entrances. Such a decision would result in a major adverse impact to

current visitor access patterns at YNP. As in alternative E, access to resources in GTNP

and the Parkway would not be expected to change, although modes of travel and amounts

of visitation to those resources could change.

Effects on Visitor Experience — Yellowstone National Park

The amount and type of winter visitor opportunities offered in YNP under alternative F

are provided in Table 131.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

398

Table 131. YNP Visitor opportunities available under alternative F.

Opportunities Miles or

Areas

Increase/

Decrease Length of Season Other

Groomed motorized route 119 -65 Mid-December to

Early March - 2

weeks

Night closure

sunrise to sunset

Groomed motorized route,

snowcoach only

0 0 Mid-December to

Early March - 2

weeks

Night closure

sunrise to sunset

Groomed motorized trail 0 0 Mid-December to

Early March - 2

weeks

Night closure

sunrise to sunset

Plowed route 76 0 Mid-December to

Early March - 2

weeks

Night closure

sunrise to sunset

Groomed nonmotorized 27 -10 Mid-December to

Early March - 2

weeks

Night closure

sunrise to sunset

Warming huts +7 +1 Mid-December to

Early March - 2

weeks

Night closure

sunrise to sunset

Backcountry 2.2

million

acres

-2 million

acres of

accessible

area

Backcountry closed

to visitation

Visitor Satisfaction and Experience

Opportunities to view wildlife. Under alternative F opportunities to view wildlife

would be eliminated from the following road sections: Mammoth to Norris Junction,

Norris Junction to Madison Junction, Madison Junction to Old Faithful, and Madison

Junction to West Entrance. Currently 105,500 winter visitors use these entrances

annually.

Opportunities to view wildlife from the backcountry of YNP would be eliminated under

this alternative because all nonmotorized activities would be limited to front country

groomed routes. See Access to winter activities below.

All other wildlife viewing opportunities would be the same as in alternative A.

Opportunities to view scenery. Under alternative F opportunities to view wildlife

would be eliminated from the following road sections: Mammoth to Norris Junction,

Norris Junction to Madison Junction, Madison Junction to Old Faithful, and Madison

Junction to West Entrance.

Opportunities to view scenery from the YNP backcountry would be eliminated under this

alternative. See The availability of access to winter activities or experiences below.
IMPACTS OF IMPLEMENTING ALTERNATIVE F

399

All other scenery viewing opportunities would be the same as in alternative A.

Safety (the safe behavior of others). Same as alternative A for all open road segments.

Quality of the groomed surface. If winter use increases substantially in other areas of

the park, the quality of the groomed surfaces there could decrease substantially. If

grooming operations begin immediately after park closure, roads would have time to

refreeze resulting in an improved visitor experience.

The availability of access to winter activities or experiences. Current winter visitors

entering from the West and North Entrances account for about 73% of all winter visitors.

Recent survey respondents indicated that about 25% would not visit the parks if the West

and North Entrances were closed. Opportunities for these visitors would either be

eliminated or available at another park entrance. The Grand Loop experience for

oversnow transportation would be eliminated (affecting about 10% of current day users).

Visitors wishing to access Old Faithful would be required to travel additional distances

(an additional 15 miles from the South Entrance). Closure of YNP from sunset to sunrise

would result in additional inconvenience to paid visitors and employees. Nighttime

closures would also eliminate the opportunity to dine at the Snowlodge in the evening

and then access lodging outside the park.

The elimination of backcountry skiing would result in major adverse impacts on the

experience of viewing wildlife and scenery for visitors in this user group (About 10% of

all winter visitors to YNP (Littlejohn 1996).)

 Availability of information. Same as alternative A.

Quiet and Solitude. Some improvements in snowmobile sound emissions technologies

are expected. For all open areas of the park, opportunities for quiet and solitude would

be the same as described in alternative A.

Clean air. Some improvements in snowmobile emissions technologies are expected.

For all open areas of the park, opportunities for clean air would be the same as described

in alternative A.

Conclusion

The elimination of winter opportunities on the road segments connecting the West and

North Entrances with Old Faithful would result in major adverse impacts on the desired

experience for current winter visitors. Other areas of the park could receive an increase

in use if mitigation strategies were not implemented. If winter use increases in other

areas of the parks, the result would be an increase in snowmachine emissions and a

periodic loss of a clean air environment. Moderate adverse impacts would be expected

on visitor experiences in those areas.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

400

The elimination of backcountry skiing in YNP would result in major adverse impacts on

the experience of viewing wildlife and scenery for these users.

Effects on Visitor Experience — Grand Teton National Park and the

Parkway

The amount and type of winter visitor opportunities offered in GTNP under alternative F

are provided in Table 132.

Table 132. GTNP Visitor opportunities available under alternative F.

Opportunities

Miles or

Areas

Increase/

Decrease Length of Season Other

Groomed motorized route 2.1 0 December to

April†

Nighttime closure –

sunset to sunrise

Groomed motorized route,

snowcoach

2.1 0 December to

April†

Nighttime closure –

sunset to sunrise

Groomed motorized trail 8 -26 December to

April†

Nighttime closure –

sunset to sunrise

Plowed road 94.4 -5.6 December to

April†

Nighttime closure –

sunset to sunrise

Ungroomed motorized trail

or area

0 -35.6 December to

April†

Nighttime closure –

sunset to sunrise

Groomed nonmotorized 0 0 December to

April†

Nighttime closure –

sunset to sunrise

Ungroomed nonmotorized

trail or area

35 8.6 December to

April†

Nighttime closure –

sunset to sunrise

Warming huts/interpretive

centers

2 0 December to

April†

Nighttime closure –

sunset to sunrise

†

 Variable, dependent on snow conditions

Visitor Satisfaction and Experience

For all the factors that are important to the experience and satisfaction of the visitor,

alternative F is very nearly the same as alternative E. The exception to this is the

possible redistribution of oversnow motorized use from YNP’s West and North

Entrances to the South and East Entrances, as described in the Access and Circulation

section. For most of the park this is of no consequence. For the north end of the park,

where snowmobile access remains along the Grassy Lake Road to Flagg Ranch, use

could greatly increase. If significant numbers of people wish to experience YNP using

the South Entrance there could be a net increase in use or demand at Flagg Ranch where

staging would occur. The result could be an increase in snowmachine emissions and

periodic losses of a clean air environment.
IMPACTS OF IMPLEMENTING ALTERNATIVE G — THE PREFERRED ALTERNATIVE

401

IMPACTS OF IMPLEMENTING ALTERNATIVE G — THE PREFERRED

ALTERNATIVE

Effects on the Socioeconomic Environment

GYA Regional Economy. As with several other alternatives, alternative G contains

several provisions for relatively minor changes in trail management within YNP and

GTNP. Most of these changes are unlikely to substantially impact visitor decisions on

whether or not to visit the parks for recreation. One proposed management change,

however, has the potential to substantially impact visitation levels to the GYA and,

therefore, visitor expenditures and the overall level of economic activity within the GYA.

Alternative G contains a proposal to allow only oversnow mass transit vehicles

(snowcoaches) that can meet strict emissions and sound requirements.

The 1999 GYA winter visitor survey asked respondents how their visitation would be

affected if both YNP and GTNP were open only to snowcoach, skiing, and snowshoeing.

Based on the responses to this survey question, visitation to the GYA by winter visitors

who live outside the five-county area would be reduced by 33.4% if winter travel were

restricted to either snowcoach or nonmotorized travel. This estimated reduction in

visitation is a net change that considers the responses of those current winter visitors who

said they would visit more often if the change occurred. Also considered in the

calculation were those respondents who said they would visit the same, but shift their use

to other areas of the GYA (for example, from park lands to national forest lands). Table

133 shows that for the largest classes of winter user groups (snowmobilers, skiers, and

snowcoach riders), anticipated changes in visitation under alternative G vary

dramatically. While 59.6% of those who snowmobiled on their trip said that they would

visit less frequently under the alternative G changes, only 12% of skiers and 14.1% of

snowcoach riders said they would visit less frequently. Conversely, while only 5.6% of

snowmobilers said they would visit more frequently under this alternative, 33.7% of

skiers and 22.8% of snowcoach riders said they would increase their visitation. The

estimate of a 33.4% decrease in visitation to the five-county area considers the

anticipated changes in visitation by these diverse groups of winter park users.

Table 133. Visitation response to alternative G changes in winter park access: by

visitor category.

If YNP were open only to snowcoach, skiing, and snowshoeing.

Response Snowmobile Cross-Country Skiers Snowcoach

No change 17.8% 37.2% 42.5%

Would visit less frequently 59.6% 12.0% 14.1%

Would visit more frequently 5.6% 33.7% 22.8%

Would visit the same amount 4.2% 6.5% 7.8%

Not Sure 12.8% 10.7% 12.8%

Sample Size 792 247 106

In the winter visitor survey, park visitors who live outside the five-county area made up

85.9% of total sampled. If 33.4% of these visitors decided not to recreate in the GYA
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

402

because of restrictions of mechanized travel, the local economy would lose these visitors’

local-area expenditures.

Based on the winter survey responses and the IMPLAN input/output model, it is

estimated that these travel restrictions under alternative G would reduce the total

economic output in the five-county GYA area by $19.2 million. In addition it is

estimated that 454 jobs within the GYA would be lost due to reduced nonresident

expenditures in the area.

While a $19.2 million loss in output is a minor impact on the $5.7 billion economic

output of the GYA, this impact likely would be concentrated in small communities near

the three parks. The impacts of travel restrictions under alternative G on small local

economies such as West Yellowstone could be more significant. However, the

correlation between West Entrance visits and the West Yellowstone economy is not as

close as expected (Chapter III). Thus it is difficult to predict the actual effect of a change

in park visitation on the West Yellowstone economy.

The town of West Yellowstone levies a local option tax targeted at tourist spending. Tax

records show that from 1989-1999, tourist expenditures have grown at a rate of 10%

annually. Tourist spending in winter accounts for about 25% of year-round tourist

spending in West Yellowstone. Given the relative size of the West Yellowstone winter

economy to year-round totals and the recent growth trends for tourist spending, the

estimated visitation reductions associated with alternative G likely would have a

moderate to major short-term negative impact on the town’s winter economy, but a minor

impact on the year-round economy of the town. Assuming that West Yellowstone’s

economy and winter park visitation are closely related, West Yellowstone’s winter

economy would decline about 33%, while the year-round economy would decline 8%.

This decline is less than the average one-year growth rate, so even under this assumption

the impact is likely to be short term. These estimates likely overstate the impacts on

West Yellowstone. The impact projections assume that the change in the West

Yellowstone winter economy is proportional to change in park visitation. There is

considerable evidence that historical declines in winter park visitation through the West

Entrance have not resulted in proportional declines in the local economy. For example,

in winter 1995-96, West Entrance visitation decreased by 13.4% over the previous year,

but resort tax collection increased by 9.6%. This non-proportional relationship between

park visitation and the local economy is probably due to extensive winter recreational

opportunities near West Yellowstone, including 400 miles of snowmobile trails outside

YNP. The average visitor to West Yellowstone spends only one day of a multi-day trip

snowmobiling in the park. Other factors that might impact visitation levels include snow

depth, pricing policies, and advertising efforts.

The estimates of reductions in GYA visitation and nonresident expenditures are based on

survey responses of current winter visitors. The 1999 YNP summer visitor survey asked

respondents who had not previously visited the park in the winter whether they would
IMPACTS OF IMPLEMENTING ALTERNATIVE G — THE PREFERRED ALTERNATIVE

403

visit the park next winter if a snowcoach, ski, and snowshoe only policy were adopted.

Responses from this group indicate that new winter users could be attracted to YNP as a

result of the alternative. Increased visitation could serve to offset a portion of estimated

visitation losses. Rather than a 33% reduction in visitation, the reduction could be

around 25%. As noted by some local businesses in DEIS comments, a policy change

may lead to economic diversification. Firms that lost business when snowmobiles

became the dominant use may benefit from a variety of users.

Three-State Regional Economy. Overall, 65.5% of winter visitors in the GYA winter

visitor survey came from outside the three-state area of Montana, Idaho, and Wyoming.

Responses from these visitors indicate that nonresident winter trips to the GYA would

drop by 27.8% under alternative G.

A loss of regional expenditures by these nonresidents would lead to an overall reduction

of $17.7 million in total economic output and 430 jobs in the three-state area. This is a

negligible, negative impact in the context of the regional three-state economy. This

estimated loss would be reduced if nonresidents choose to recreate at other locations

within the three-state region instead of the GYA. The extent of this estimated loss,

however, is unknown.

Responses from the summer YNP visitor population survey indicate that increased

interest in visiting the park in the winter months under the alternative G management

policies may lead to an approximate 11% increase in winter visitation. An active public

education and awareness campaign, directed at the summer visitor population, which

focuses on the parks’ new winter use opportunities, may partially offset the expected loss

of non-resident winter users. This education and awareness campaign can operate in

partnership with the parks’ gateway communities, state agency cooperators, and private

businesses.

Minority and Low-Income Populations. Alternative G would eliminate the primary

mode of current winter access to the parks — snowmobiling. To the extent that current

snowmobile visitors to the park would now use snowcoach access under alternative G,

the price of snowcoach access to the park could rise, impacting low-income winter visitor

access to the park.

A portion of currently operated snowcoaches would not meet the emission and sound

requirements of alternative G. These older snowcoaches would either need to be

replaced or eliminated ,which likely would place further upward pressure on the price of

snowcoach access to the park, and would negatively impact low-income visitors to the

park.

Social Values. Most winter visitors surveyed support mechanized access to the parks. In

the context of overall access to the park, the changes proposed in alternative G are likely

to result in major adverse impacts by eliminating some of the most heavily used winter

motorized routes within the parks. Conversely, a portion of winter users favor reductions
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

404

in motorized use within the park. For this group, the alternative G travel restrictions

would have a positive impact.

Current winter visitors to YNP are attracted by the current set of recreation opportunities,

which include snowmobiling. These visitors support current management. Among

summer visitors (as detailed in Chapter III), there is less support for current management.

Among the general public, local residents are evenly divided between support for current

management versus alternative G. However, this probably varies by county. For

example, the Teton County, Wyoming survey (discussed in Chapter III) found a much

higher overall local participation in cross-country skiing (mostly in GTNP) than

snowmobiling. A majority of local residents feel that snowmobiles negatively impact

Yellowstone in the winter and that snowmobiles should be limited in YNP in winter.

Among the regional and national populations, many respondents favor the snowcoach

option over the existing policy. For this group, alternative G would have a positive

impact.

The potential for a successful shift in the type of winter recreation activity in this

alternative indicated by participation rates. For example, nationally, regionally, and

locally, cross-country skiing is just as, or slightly more, popular than snowmobiling. A

decrease in opportunities for snowmobiles in YNP may shift participation rates to other

winter activities such as cross-country skiing. A shift would be assisted by increased

awareness and education programs alerting a national population about changing

opportunities (via state tourism programs, business marketing, and NPS visitor

information services).

Nonmarket Values. Alternative G potentially would impact nonmarket values of winter

visitors through a reduction in current winter user visitation resulting from the restriction

of mechanized travel to clean, quiet snowcoaches.

Based on the winter visitor survey, the nonmarket value of a trip to GYA parks is $91. It

is estimated that park visitation would be reduced by 33.4% resulting from the

management change. Based on current winter visitation levels, a 33.4% reduction in

visitation would translate into a $2.7 million reduction in the aggregate nonmarket value

of winter trips to the parks. This is a moderate negative impact. These estimates are

based on reduced use by current visitors.

Conclusion

Alternative G management actions would have a negligible to minor negative impact on

the five-county economy and a negligible negative to positive effect on the three-state

economy through changes in visitation and nonresident visitor expenditures. Given the

historical lack of correlation between year-to-year changes in winter visitation to YNP

and the West Yellowstone economy, the reduced visitor expenditures under this

alternative could have a moderate to negligible short-term adverse impact on the winter

economy of West Yellowstone, Montana. The impact on the year-round West
IMPACTS OF IMPLEMENTING ALTERNATIVE G — THE PREFERRED ALTERNATIVE

405

Yellowstone economy is, at worst, a moderate short-term negative impact. Alternative G

also would have a minor negative impact on total current trip nonmarket visitor benefits

(through reduced visitation). The changes proposed in alternative G are likely to result in

moderate adverse impacts to some visitors’ social values and a moderate positive impact

on other users’ social values. This alternative could have an unspecified adverse impact

on low-income visitor access to the park.

Summary of Estimated Visitation Changes from Alternative Winter Management

Options. Eight specific impact estimates were calculated for the Final Environmental

Impact Statement (FEIS) corresponding to estimates for two analysis areas for each of

four alternative management options. Table 134 details the changes in total economic

output and employment associated with each of the estimates. In all four winter

management options, the estimated output and employment impact for the two analysis

areas are less than 0.5% baseline levels.

Table 134. Estimated economic output and employment impacts of alternative

winter management options.

Management Change

Analysis

Area

Change in

Output (Million

1997 Dollars)

% Change

in Output

Change in

Employment

% Change in

Employment

Alternative B — 5-county -13.2 -0.23% -312 -0.32%

Plow road from West

Yellowstone To Old

Faithful 3-state -14.4 -0.01% -351 -0.02%

Alternative G — 5-county -14.4 to –19.2 -0.34% -340 to –454 -0.47%

Snowcoach, skiing,

snowshoe access

only† 3-state -17.7 to +7.0 -0.02% -430 to +170 -0.03%

Alternative F — 5-county -14.4 -0.25% -340 -0.35%

Westside closure to

all vehicles in winter 3-state -13.7 -0.01% -334 -0.02%

Alternative D — Stop 5-county -1.3 -0.02% -32 -0.03%

plowing from Colter

to South Entrance 3-state +0.2 0% +4 0%

†

 Increased winter visitation from current summer visitors to the park under this management option could substantially

offset the estimated output and employment reductions from current winter visitors. This would depend in part on

marketing and education programs implemented through the Winter Use Plan in cooperation with states and gateway

communities.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

406

An analysis of the regional economic and nonmarket impacts of alternative G, prepared

by the State of Wyoming, is as follows:

“The Draft Winter Use Plan/Environmental Impact Statement for the Yellowstone and Grand

Teton National Parks and John D. Rockefeller, Jr. Memorial Parkway states that:

‘The direct, indirect and induced expenditures generated in the GYA by nonresidents visiting

the parks in the winter months are estimated to be about $63 million.’

Table 19 of the DEIS indicates that 61% of the winter visitors to YNP snowmobile. Table 28

indicates that 97% of the winter visitors to GTNP snowmobile. A weighted average of winter

visitors to the two parks indicates that 67% of the combined YNP and GTNP winter visitors

snowmobile. Based on the methodology in the Draft EIS it might be assumed that 67% of the

$63 million of economic impact from winter visitors in the parks is associated with

snowmobiling.

However, previous research in YNP indicates that snowmobilers tend to spend more than

other winter visitors. For example, Littlejohn (1996) indicates that snowmobilers in YNP

spend almost twice as much as cross-country skiers ($224 vs. $116). If this pattern holds for

other winter visitors it would mean that while snowmobilers represent 67% of winter visitors,

they represent 80% of the total economic impact of winter visitors in the GYA or $48 million

($60 million x 0.80). This could be the potential loss to the GYA under alternative G from

banning snowmobiles.

Based on information for alternative G of the Draft EIS, it is estimated that the total

nonmarket value of winter trips to the GYA parks was about $29 million. Again based on the

methodology used in the Draft EIS, it might be assumed that 67% of the $29 million in

nonmarket value of winter trips to GYA parks is associated with snowmobiling. However,

previous research indicates that snowmobilers value their trips more than other winter visitors.

For example, the value of snowmobiling of participants was 2.8 times that for cross-country

skiing, sightseeing, or general recreation. If this pattern holds for winter visitors to GYA

parks it would mean that while snowmobilers represent 67% of the winter visitors represent

85% of nonmarket value of winter trips to GYA parks or $24.65 million ($29 million x 0.85).

This could be the potential loss to the GYA under alternative G from banning snowmobiles.”

This analysis by the State of Wyoming is based on several assumptions about

snowmobiler behavior that are not supported by the results of the 1999 GYA winter

visitor study. Specifically it assumes that (1) all snowmobile use in the parks will be lost

to the GYA; (2) that other types of users (snowcoach, skiers) will not increase use; and

(3) that all park day entries actually count as multi-day trips (equivalent to assuming zero

re-entry). Other things being equal, these assumptions may lead to overstating impacts

by a factor of three to four.

Effects on Air Quality and Public Health

Alternative G emphasizes clean, quiet oversnow access to the parks by restricting travel

only to oversnow mass transit vehicles that can meet strict emissions and sound

requirements. For example, an estimated 80 to 90 snowcoaches per day would operate

on the West Entrance to Old Faithful Road, replacing the current January-February

average of 550 snowmobiles per day. Table 135, Table 136, and Table 137 summarize

the results of CO modeling for six locations in the three parks for alternative G. Table

135 and
IMPACTS OF IMPLEMENTING ALTERNATIVE G — THE PREFERRED ALTERNATIVE

407

Table 136 show the predicted maximum 1-hour average CO concentrations and the

calculated maximum 8-hour average CO concentrations, respectively. The percent

contribution of each vehicle type to the maximum CO concentrations also is provided in

Table 137 for the six locations. Table 138 and Table 139 provide corresponding model

results for PM10 for the same locations and conditions as those for CO.

Table 135. Maximum 1-hour average CO concentrations for alternative G.

Location

1-hr Maximum

Concentration

(w/o Background)

(ppm)

1-hr Maximum

Concentration

(w/Background)

(ppm)

Change Relative

to Alternative A

(w/o Background)

(%)

West Yellowstone Entrance 1.50 4.50 94.9

West Entrance to Madison Roadway 0.50 3.50 95.8

Old Faithful Staging Area 1.20 4.20 7.1

Flagg Ranch Staging Area 1.63 4.63 5.3

Flagg Ranch to Colter Bay Roadway 0.20 3.20 81.8

Mammoth to NE Entrance Roadway 0.30 3.30 0
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408

Table 136. Maximum 8-hour average CO concentrations for alternative G.

Location

8-hr Maximum

Concentration

(w/o Background)

(ppm)

8-hr Maximum

Concentration (w/

Background)

(ppm)

Change Relative

to Alternative A

(w/o Background)

(%)

West Yellowstone Entrance 0.71†

2.12†94.9

West Entrance to Madison Roadway 0.24†

1.65†95.8

Old Faithful Staging Area 0.20 1.60 7.1

Flagg Ranch Staging Area 0.27 1.68 5.3

Flagg Ranch to Colter Bay Roadway 0.09†

1.51†81.8

Mammoth to NE Entrance Roadway 0.14†

1.55†0

†Estimated from the modeled maximum 1-hour average concentration based on the persistence formula

Ct2 = Ct1*(t1/t2)^0.365 (Cooper and Alley 1990).

Table 137. Vehicle contribution to CO concentrations for alternative G.

Contribution (%)

Location SM SC AM LT HT TB SV

West Yellowstone Entrance 0 98.6 0 0 1.4 0 0

West Entrance to Madison Roadway 0 99.1 0 0 0.9 0 0

Old Faithful Staging Area 0 99.5 0 0 0.5 0 0

Flagg Ranch Staging Area 0 98.9 0 0 1.1 0 0

Flagg Ranch to Colter Bay Roadway 0 99.1 0 0 0.9 0 0

Mammoth to NE Entrance Roadway 0 0 26.5 66.9 0.5 0 6.1

SM = snowmobile, SC = snowcoach, AM = automobile, LT = light truck, HT = heavy truck, TB = tour bus, SV = shuttle van.
IMPACTS OF IMPLEMENTING ALTERNATIVE G — THE PREFERRED ALTERNATIVE

409

Table 138. Maximum 24-hour average PM10 concentrations for alternative G.

Location

24-hr Maximum

Concentration

(w/o Background)

(ppm)

24-hr Maximum

Concentration

(w/Background)

(ppm)

Change Relative to

Alternative A (w/o

Background)

(%)

West Yellowstone Entrance 0.32†23.32 99.3

West Entrance to Madison Roadway 0.32†23.32 97.1

Old Faithful Staging Area 0.01 5.01 98.3

Flagg Ranch Staging Area 0.03 5.03 94.9

Flagg Ranch to Colter Bay Roadway 0

†

5.00 100.0

Mammoth to NE Entrance Roadway 0.32†5.32 0

†Estimated from the modeled maximum 1-hour average concentration based on the persistence formula

 Ct2 = Ct1*(t1/t2)^0.365 (Cooper and Alley 1990).

Table 139. Vehicle contribution to PM10 concentrations for alternative G.

Contribution (%)

Location SM SC AM LT HT TB SV

West Yellowstone Entrance 0 28.9 0 0 71.1 0 0

West Entrance to Madison Roadway 0 50.1 0 0 49.9 0 0

Old Faithful Staging Area 0 1.6 0 0 98.4 0 0

Flagg Ranch Staging Area 0 0.7 0 0 99.3 0 0

Flagg Ranch to Colter Bay Roadway 0 50.1 0 0 49.9 0 0

Mammoth to NE Entrance Roadway 0 0 22.5 46.6 26.7 0 4.2

SM = snowmobile, SC = snowcoach, AM = automobile, LT = light truck, HT = heavy truck, TB = tour bus, SV = shuttle van.

Visibility

The visibility assessment indicates that under alternative G, vehicle emissions would not

cause any perceptible visibility impairment in the vicinity of the West Entrance, along the

roadways, or in the vicinity of Old Faithful and Flagg Ranch.

Conclusion

As noted in Table 135, Table 136, and Table 138, the model predicts major beneficial

impacts on CO and PM10 levels, relative to alternative A at the West Entrance and along

the West Entrance to Madison road. The Old Faithful and Flagg Ranch staging areas

would see a minor beneficial impact on CO levels and a major beneficial impact on PM10

levels. Major beneficial impacts from reduced CO and PM10 concentrations are predicted

along the Flagg Ranch to Colter Bay roadway. These decreased concentrations would

result from elimination of snowmobiles.

Effects on Public Safety

Late night oversnow travel would be prohibited from 11:00 P.M. to 5:00 A.M. in all three

parks. This action would eliminate any potential for nighttime collisions between
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ENVIRONMENTAL CONSEQUENCES

410

snowmachines and wildlife. The effect of this action would be negligible since less than

1% of recorded accidents during the last three years have occurred in this time period.

The primary benefit to public safety would be that all potential for snowmobile accidents,

as well as snowmobile snowcoach conflicts, would be removed. Also, because

snowcoach drivers generally have more familiarity with the road and its wildlife patterns

than the casual visitor, the elimination of private vehicles on this road would reduce the

overall potential for motor vehicle accidents (snowcoaches are involved in less than 3%

of accidents). In addition this alternative eliminates the potential for inter-modal

conflicts between different types of snowmachines and facilitates nightly grooming,

which is also a benefit to safety.

In GTNP closing the road between Colter Bay and Flagg Ranch to wheeled-vehicles

would eliminate the potential for inter-modal conflict along this stretch of the CDST. It

would eliminate a major source of winter vehicle accidents, vehicle-wildlife accidents

and unsafe vehicular activity. Elimination of both snowmobiles and snowplanes from the

surface of Jackson Lake would also eliminate the potential for user conflicts and

accidents involving poor ice on the lake’s frozen surface.

Conclusion

The benefits of implementing this alternative would be long term, major and beneficial

due to the elimination of all potential snowmobile accidents in the three parks. These

impacts would affect employees and visitors.

Effects on Geothermal Features

Under this alternative, roads would be groomed and access would be allowed only with

mass transit vehicles. Using mass transit would allow park management some control

over what stops along the roadway, thus increasing protection for geothermal features in

areas where there are adverse levels of impact. The increase in opportunities to inform

visitors of adverse impacts on geothermal resources would provide minor beneficial

improvements to the protection of geothermal features.

The impacts of unrestricted backcountry use and the grooming of nonmotorized trails in

Mammoth Terraces, Lone Star Geyser Basin, and Fountain Flats would be the same as

those described under alternatives A and C.

Conclusion

Under this alternative the protection of geothermal features would be improved, although

minor adverse impacts may occur to Fountain Flats and backcountry geothermal features.

Effects on Water and Aquatic Resources

Potential pollution sources are the same as described in alternative A. The potential

impacts along all road segments would decrease with the prohibition of snowmobiles.

Table 140. Snowmachines and associated risk levels for alternative G.
IMPACTS OF IMPLEMENTING ALTERNATIVE G — THE PREFERRED ALTERNATIVE

411

Impact: Daily Vehicle

Miles Traveled Along

the Segment in Alt. A†

Impact: Daily Vehicle

Miles Traveled Along

the Segment in Alt. G†

Road Segment

Risk ±

Rating‡ SM‡ SC SM SC

Mammoth to Norris Medium 641 69 0 168

West Entrance to Madison Medium 7759 127 0 1232

Madison to Norris High 3458 73 0 560

Norris to Canyon Village Low 2214 47 0 360

Canyon Village to Fishing Bridge High 2370 50 0 384

Fishing Bridge to East Entrance Medium 983 0 0 135

Fishing Bridge to West Thumb Medium 2627 55 0 420

Madison to Old Faithful High 7818 165 0 1280

Old Faithful to West Thumb Medium 3560 73 0 578

West Thumb to Flagg Ranch Medium 4219 103 0 696

Grassy Lake Road High 184 0 0 32

Flagg Ranch to Colter Bay Low 379 0 0 464

Colter Bay to Moran Junction High 248 0 0 0

Moran Junction to East Entrance Medium 49 0 0 0

Teton Park Road Low 156 0 0 0

Moose-Wilson Road Low 6 0 0 0

†SM = Snowmobile, SC = Snowcoach; The source of pollutants is emissions from snowmobiles, which produce

(conservatively) 10 times as many emissions per mile as most wheeled vehicles. Single snowcoaches produce fewer

emissions than single snowmobiles.

‡±High = within 100 meters of aquatic system on 76% to 100% of the road segment; Medium = within 100 meters on 51%

to 75% of the road segment; Low risk segments are within 100 meters of rivers less than 50%.

Conclusion

Deposition into snowpack from 2-stroke engine emissions along groomed park roads in

YNP and GTNP would be eliminated. Emissions from snowcoaches, with improvements

phased in, would continue to be deposited in snowpacks, at lower volumes over time.

The effect of this deposition on water quality is undetermined but there is currently no

evidence of measurable changes in water quality or effects on aquatic resources. It is

possible that accumulations of pollutants in aquatic systems may have adverse impacts on

wetlands and aquatic resources downstream from high risk road segments. Oversnow

vehicle use in this alternative involves localized high risk to surface water quality, but

reduces oversnow vehicle-miles traveled along high risk road segments in the three park

units by about 84%. It would reduce oversnow vehicle-miles traveled along medium risk

road segments by about 84%. The risk of moderate to major adverse impacts on water

quality in Jackson Lake would be eliminated.

Mitigation

Best management practices would be utilized during the construction, reconstruction, or

winter plowing of trails and roads to prevent unnecessary vegetation removal, erosion,

and sedimentation. The release of snowpack contaminants into surface water could be
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ENVIRONMENTAL CONSEQUENCES

412

mitigated by disconnecting snowmelt drainages from trails by oversnow vehicles. Any

new or reconstructed winter use sanitary facilities would be constructed in locations and

use advanced technologies that would protect water resources. A focused program of

monitoring would reduce the uncertainty of impacts from oversnow vehicles and, if

necessary, indicate best management practices that might be implemented.

Effects on Wildlife

Ungulates

Effects of groomed roads and trails. Packed trails may influence wildlife movements

and distributions by facilitating travel into areas that would normally be inaccessible due

to deep snow. Under alternative G, YNP would groom an additional 4 miles (of

previously designated route) over alternative A for a total of 225 miles, and GTNP and

the parkway would groom about 24 miles (12 miles less than alternative A due to the

elimination of the CDST).

The impacts associated with groomed surfaces would decrease relative to alternative A

for GTNP, and remain the same for YNP. Under this alternative, adaptive management

could be employed to revise management of groomed roads should monitoring and

research clearly indicate adverse effects to bison and other ungulates.

Effects of motorized oversnow use of groomed and ungroomed roads and trails. The

use of motorized oversnow vehicles can cause injury and death for wildlife, especially in

poor lighting conditions and during snowfall, and can cause displacement from preferred

habitats.

This alternative reduces the potential effects on ungulates by eliminating snowmobile

use. A minor risk of collision and short-term stress-induced movement would continue

with the use of snowcoaches. However, compared to current levels of snowmobile use,

traffic levels would be reduced by a factor of eight, and no ungulates have been struck by

snowcoaches (Gunther et al. 1998). Furthermore, NPS policy would require that

snowcoach drivers be trained and that stops be made only in areas where wildlife would

be unaffected. The elimination of the CDST would benefit moose because this route

intersects moose winter range in the northern part of GTNP. In all parks, collisions

would be mitigated by the prohibition on oversnow motorized use from 11 P.M. to 5 A.M.

Effects of plowed roads. Road plowing may cause habitat fragmentation by creating

structural barriers (i.e., snow berms) to ungulate movements (Aune 1981). In addition

plowed roads, like groomed roads, also may provide an energy efficient mechanism for

wildlife movements, including bison, elk, and moose. Under alternative G, YNP would

plow 76 miles of road for wheeled-vehicle access in the winter, the same as under current

management. GTNP would plow 82 miles, a reduction of 17 miles as a result of

replacing wheeled-vehicles with snowcoaches from Colter Bay north to Flagg Ranch.
IMPACTS OF IMPLEMENTING ALTERNATIVE G — THE PREFERRED ALTERNATIVE

413

For YNP, the effects associated with plowed roads would be the same as alternative A.

Effects associated with plowed roads in GTNP would be the same as those described in

alternative D. Relative to current management, impacts would be reduced and negligible,

especially for moose north of Colter Bay in GTNP.

Effects of motorized use of plowed roads. The effects of plowed roads are similar to

those of groomed roads, except that the magnitude of the effect is usually greater. The

use of motorized vehicles on plowed roads can cause injury and death for wildlife,

especially in poor lighting conditions, at dusk and dawn, and during snowfall, and can

cause displacement from preferred habitats.

For YNP, the effects associated with plowed roads would be the same as alternative A.

Effects associated with plowed roads in GTNP would be the same as those described in

alternative D. Relative to current management, impacts would be reduced and negligible,

especially for moose north of Colter Bay in GTNP.

Effects of nonmotorized use of groomed and designated ungroomed routes. The

primary effects of nonmotorized use on ungulates are displacement from preferred

habitats, especially geothermal areas that are important for winter survival in YNP, and

increased energy expenditures, including physiological stress, which may reduce

individuals’ chances of survival. In alternative G, YNP offers 37 miles of groomed

nonmotorized routes, the same as alternative A, and GTNP and the Parkway remain the

same at 26 miles.

The level of impact in the parks would be the same as alternative A — minor.

Effects of unregulated backcountry nonmotorized use. Unregulated backcountry

nonmotorized use is more random and infrequent relative to nonmotorized use on

designated routes. Consequently, although encounters between backcountry users and

ungulates may only occur sporadically, they can be especially disturbing and lead to

additional energy expenditure and stress that reduces animals’ chances of survival and

reproduction. Under alternative G, nonmotorized uses in certain wildlife winter ranges

and thermal areas would be restricted to travel on designated routes only.

Effects decrease relative to alternative A. In GTNP winter use in important bighorn

sheep winter ranges would be restricted or prohibited, including areas in the north and

south Teton Range.43

 

43 Southern Tetons: (1) in the Prospectors Mt. and Mt. Hunt areas (including peak 10988), all areas

above 3000m (9,900 ft.), and south-facing slopes on Mt. Hunt above 2600m (8,580 ft.); (2) the

slopes of Static Peak above 3300m (10,890 ft.) (does not affect Albright Peak); and (3) the southfacing slopes above 3000m (9900 ft.) along the north side of Avalanche Canyon and the north fork

of Avalanche Canyon.

Northern Tetons: 1) in the Ranger-Doane-Eagles Rest area (including peaks 10,298; 10,881;

10,023; 10,686), all areas above 3,000 m (9,900 ft.), and south-facing slopes of Eagles Rest above

2,600m (8,580 ft.); 2) in the Elk Mt.-Owl Peak area, all areas above 3,000 m (9,900 ft.), and southfacing slopes above 2,600m (8,580 ft.); 3) on Forellen Peak, all areas above 2,800 m (9,240 ft.)
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

414

Effects of the presence and use of winter support facilities. Increases in human

activity associated with the presence of support facilities may displace species sensitive

to human disturbance. Under this alternative, a warming hut would be constructed at

Norris in the vicinity of ungulate winter range important to elk, deer, and bison.

Introducing winter human use into this area would reduce its habitat effectiveness by

potentially causing these species to be displaced to lower quality habitats. However, over

time, the predictable nature of the recreation expected to occur in the area may allow

these species to habituate to the increase in human activity. Effects could be the same as

in alternative A, minor and short term.

Federally Protected Species

Effects of groomed roads and trails. Packed trails may influence wildlife movements

and distributions by facilitating travel into areas that would normally be inaccessible due

to deep snow. Under alternative G, YNP would groom an additional 4 miles (of

previously designated route) over alternative A for a total of 225 miles, and GTNP and

the Parkway would groom about 24 miles (12 miles less than alternative A due to the

elimination of the CDST).

Impacts related to packed trails would be less relative to alternative A in GTNP and

remain the same in YNP. The extent to which packed surfaces influence lynx in the

parks are largely unknown but would be investigated (see mitigation).

Effects of motorized use of groomed and ungroomed roads and trails. The use of

motorized oversnow vehicles can cause displacement from preferred habitats. Collision

impacts from oversnow motorized vehicles have not been documented for any of the

federally protected species in the parks.

Impacts are generally decreased relative to alternative A. The elimination of

snowmobiles from the three parks would decrease impacts related to noise and

displacement. Use of snowcoaches would continue to potentially displace lynx because

these routes pass through areas of lynx habitat, but the effects of snowcoaches would be

less than those associated with snowmobiles because snowmobiles would be fewer in

number and slower. Because the majority of visitors would be traveling on NPSmanaged snowcoaches, the ability to control where and when stops are made would

benefit all species. If federally protected species activity is detected, park managers can

close the area to human activity to mitigate disturbance.

Effects of plowed roads. Road plowing may cause habitat fragmentation by creating

structural barriers (i.e., snow berms) to wildlife movements (Aune 1981). In addition

similar to groomed roads, plowed roads may influence wildlife movements and

distributions by facilitating travel into areas that would normally be inaccessible due to

 

and south-facing slopes above 2,500 m (8,250 ft.); and 4) the ridgecrest and south-facing slopes of

the cliffs at the mouth of Moose Creek (also known as the “Lower Berry Cliffs”) above 2,300 m

(7,590 ft.).
IMPACTS OF IMPLEMENTING ALTERNATIVE G — THE PREFERRED ALTERNATIVE

415

deep snow. Under alternative G, YNP would plow 76 miles of road for wheeled-vehicle

access in the winter, the same as under current management. GTNP would plow 83

miles, a reduction of 17 miles as a result of replacing wheeled vehicles with snowcoaches

from Colter Bay north to Flagg Ranch.

Impacts are generally as stated in alternative A for YNP and would decrease in GTNP. If

protected species are detected in an area, park managers can close the area to human

activity to mitigate disturbance.

Effects of motorized use of plowed roads. The effects of traffic on plowed roads are

similar to those of traffic on groomed roads, except that the magnitude of the effect is

usually greater. The use of motorized vehicles on plowed roads can cause injury and

death to wildlife, especially in poor lighting conditions, at dusk and dawn, and during

snowfall, and can cause displacement from preferred habitats.

Impacts are generally as stated in alternative A — none to minor. Collision impacts to

wolves and lynx may be reduced by the elimination of wheeled vehicles on the road from

Colter Bay to Flagg Ranch.

Effects of nonmotorized use on groomed and designated ungroomed routes. The

primary effects of nonmotorized use on wildlife are displacement from preferred habitats

and increased energy expenditures, including physiological stress, which may reduce

individuals’ chances of survival. In alternative G, YNP offers 37 miles of groomed

nonmotorized routes, the same as alternative A, and GTNP and the Parkway would

remain the same at 26 miles.

Impacts are generally as stated in alternative A — none to negligible.

Effects of unregulated backcountry nonmotorized use. Unregulated backcountry

nonmotorized use is more random and infrequent relative to nonmotorized use on

designated routes. Consequently, although encounters between backcountry users and

federally protected wildlife species may only occur sporadically, they may cause

displacement and additional energy expenditure and stress that reduces animals’ chances

of survival and reproduction. Under alternative G, nonmotorized uses in certain wildlife

winter ranges and thermal areas are restricted to travel on designated routes only, or

closed to use entirely.

The potential for bear-human confrontation or conflicts due to the earlier opening of the

winter use season (Thanksgiving weekend) would be limited to nonmotorized users who

leave the road corridor and travel into high-elevation areas frequented by bears prior to

denning. The likelihood of visitors coming into contact with grizzly bears during this

time would be small. Although some bears (about 10%) may still be active in late

November, park visitation at this time is expected to be low due to generally poor snow

conditions, thus the earlier opening date would not be expected to result in a substantial

increase in early winter visitation. Furthermore, based on visitation records for the past
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ENVIRONMENTAL CONSEQUENCES

416

seven years, an average of 12,485 people visited the parks in December to participate in

oversnow-related activities. Calculated on a per day basis for the period of time from

November 27 to December 15 (the initiation of the winter use season that coincides with

the time when some bears may still be active), about 8,442 visitors. Skiers comprise

about 20% of this figure (1,688). Of this 20%, half (844) indicated that they ski for less

than four hours (Littlejohn 1996). Thus, it can be inferred that these skiers were not

backcountry users, but remained on the groomed roads or trails in the front country,

consequently, the odds of their encountering grizzly bears are small. Other surveys

estimated the percentage of visitors who come to the park to ski as 10% (Borrie et al.

1999) and 24% (Duffield and Neher 1999). To minimize potential conflicts between

visitors and bears during the pre-denning period, visitors in certain wildlife winter ranges

would be restricted to designated trails, and according to park policy, other areas where

pre-denning activity is high may close at the discretion of park managers.

Restrictions on use would reduce the level of effect relative to alternative A. Closures

and restrictions may help to mitigate any increased potential for human-bear conflicts due

to the earlier opening date of the winter use season (Thanksgiving weekend).

Presence and use of winter support facilities. Warming huts and campgrounds can

cause habituation in some wildlife species by the presence of human food and garbage,

and can lead to human-wildlife conflicts. In addition increased human activity associated

with the presence of support facilities may displace species sensitive to human

disturbance. A warming hut at Norris is the only new facility proposed under alternative

G.

Potential impacts are generally as stated in alternative A — none to minor. All

alternatives call for the construction of wildlife-proof garbage facilities to mitigate the

potential effect of habituating animals, particularly bears.

Species of Special Concern

Effects of groomed roads and trails. Packed trails may influence wildlife movements

and distributions by facilitating travel into areas that would normally be inaccessible due

to deep snow; inhibit foraging activities of carnivores that tunnel beneath the snow to

hunt subnivian prey; and reduce subnivian prey availability by increasing mortality of

these small mammals. Under alternative G, YNP would groom an additional 4 miles

over alternative A (of previously designated route) for a total of 225 miles, and GTNP

and the Parkway would groom 24 miles (12 miles less than alternative A due to the

elimination of the CDST).

For all species, known impacts related to packed trails are generally as stated in

alternative A — none to negligible. In GTNP the reduction in packed surface area

relative to alternative A would potentially benefit the ability of martens to tunnel and

forage under the snow.
IMPACTS OF IMPLEMENTING ALTERNATIVE G — THE PREFERRED ALTERNATIVE

417

Effects of motorized oversnow use of groomed and ungroomed roads and trails. The

most likely impacts to park sensitive species are displacement from preferred habitats,

and degradation of the aquatic environment from pollutants in the snowpack.

Documented mortality caused by collisions with oversnow vehicles in the parks is rare —

in 10 years only one of these species (a marten) was reportedly killed by a snowmobile in

YNP (Gunther et al. 1998).

Impacts are generally as stated in alternative A — none to minor. The elimination of

snowmobiles from the parks would decrease impacts related to noise and displacement.

Use of motorized oversnow vehicles would continue to potentially displace fishers,

martens, and, in YNP, swans. Because the majority of visitors would be traveling in

snowcoaches, the ability to control where and when stops are made would potentially

benefit all species. In addition effects associated with motorized use would decrease

because snowcoaches would be fewer in number, slower, and quieter.

See Water and Aquatic Resources for an assessment of the impacts of exhaust on water

quality in the parks.

Effects of plowed roads. Similar to groomed roads, plowed roads also provide an

energy efficient mechanism for wildlife movements. Under alternative G, YNP would

plow 76 miles of road for wheeled-vehicle access in the winter, the same as under current

management. GTNP would plow 82 miles, a reduction of 17 miles as a result of

replacing wheeled vehicles with snowcoaches from Colter Bay north to Flagg Ranch.

Impacts are generally as stated in alternative A for YNP and less for GTNP. If protected

species are detected in an area, park managers can close the area to human activity to

mitigate disturbance.

Effects of motorized use of plowed roads. The most likely impact to park species of

special concern is displacement from preferred habitats and mortality caused by

collisions with wheeled-vehicles.

Impacts are generally as stated in alternative A — none to negligible. The elimination of

16 miles of plowed road from Colter Bay to Flagg Ranch would potentially decrease

effects related to displacement.

Effects of nonmotorized use on groomed and ungroomed designated routes. The

primary effects of nonmotorized use are displacement from preferred habitats, and

increased energy expenditures, including physiological stress, which may reduce

individuals’ chances of survival. In alternative G, YNP offers 37 miles of groomed

nonmotorized routes, the same as alternative A, and GTNP and the Parkway remain the

same at 26 miles.

Impacts are generally as stated in alternative A — none to minor.
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ENVIRONMENTAL CONSEQUENCES

418

Unregulated backcountry nonmotorized use. Unregulated backcountry nonmotorized

use is more random and infrequent relative to nonmotorized use on designated routes.

Consequently, although encounters between backcountry users and species of special

management concern may only occur sporadically, they can be especially disturbing and

lead to additional energy expenditure and stress that reduces animals’ chances of survival

and reproduction. Under alternative G, nonmotorized uses in certain wildlife winter

ranges and thermal areas are restricted to travel on designated routes only, or closed

entirely.

Effects associated with backcountry use would be reduced relative to alternative A.

Impacts, if they did occur, would be negligible to minor. Wolverines and other species

that consume carrion may benefit by restrictions and closures in wildlife winter ranges,

and there may be a decrease in disturbance to sagebrush lizard habitats.

Presence and use of winter support facilities. The primary effects of warming huts and

campgrounds on park species of special concern are associated with increases in human

activity and the subsequent disturbance and displacement of species or their prey. A

warming hut at Norris is the only new facility proposed under alternative G.

Potential impacts are generally as stated in alternative A — none to minor.

Conclusion

The potential levels of impacts associated with alternative G are similar to those under

alternative A – none to minor, adverse, and short term. There would be an expected

reduction or elimination of road-killed large mammals due to the elimination of

snowmobiles in all parks and the reduction in wheeled-vehicle traffic in GTNP. In

addition the replacement of individual snowmobiles with mass transit snowcoaches will

serve to decrease effects associated with displacement, including the sound, speed, and

volume of traffic. Closures or restrictions in backcountry areas also significantly

differentiate this alternative from current management, and may benefit winter-stressed

ungulates and other wildlife. Adaptive management may be employed to make

adjustments in management if and when impacts to wildlife are determined.

Although impacts to populations resulting from winter recreation are neither long-term

nor very significant, impacts to individual members of the population can be important,

leading to death either directly from collisions or continued harassment, or indirectly

through management actions taken as a response to habituation to human presence and

food. The NPS is concerned about impacts to individual animals; however, except for

federally protected species, which are protected, the NPS provides for the protection of

populations of native animals. See, for example, Chapter II, NPS 77, Natural Resources

Management.
IMPACTS OF IMPLEMENTING ALTERNATIVE G — THE PREFERRED ALTERNATIVE

419

Ungulates

• Effects of groomed roads and trails on animal movements – unknown if and to what extent

beneficial effects outweigh negative effects. Effect is reduced relative to alternative A in

GTNP.

• Effects of motorized oversnow use of groomed and ungroomed roads and trails on: 1)

mortality caused by collisions – adverse, none to negligible, and short term; and 2)

displacement from preferred habitats – adverse, negligible to minor, and short term.

Greatly reduces collision impacts over alternative A due to the elimination of snowmobiles.

• Effects of plowed roads on: 1) habitat fragmentation – adverse, minor, and short term; and

2) animal movements – unknown if and to what extent beneficial effects outweigh negative

effects (same as alternative A for YNP). In GTNP effects would decrease as compared to

alternative A.

• Effects of motorized use of plowed roads on: 1) mortality caused by collisions – adverse,

minor, and short term; and 2) displacement from preferred habitats – adverse, moderate,

and long term (same as alternative A for YNP). In GTNP effects would decrease as

compared to alternative A.

• Effects of nonmotorized use of groomed and designated ungroomed routes on displacement

from preferred habitats – adverse, minor, and short term. Same as alternative A.

• Effects of unregulated backcountry nonmotorized use on displacement from preferred

habitats – adverse, negligible to minor, and short term. Effects decrease relative to

alternative A due to restrictions on backcountry travel. Impacts to bighorn sheep in GTNP

would significantly decrease.

• Effects of the presence and use of winter support facilities on displacement – adverse,

minor, and short term. Same as alternative A.

Federally Protected Species

• Effects of groomed roads and trails on animal movements: 1) bald eagles, grizzly bears,

and wolves — no effect; and 2) lynx – adverse, negligible to major, and short term,

depending upon lynx distribution and abundance in the parks. Effect is decreased relative

to alternative A in GTNP.

• Effects of motorized oversnow use of groomed and ungroomed roads and trails on

displacement from preferred habitats – adverse, negligible, and short term for all species

excluding the grizzly bear, which typically is not active during the winter use season.

Effect is decreased relative to alternative A due to the elimination of snowmobiles.

• Effects of plowed roads on: 1) habitat fragmentation – no effect on any of the listed

species; and 2) animal movements – no known effect on any of the listed species. Same as

alternative A for YNP and less than alternative A for GTNP.

• Effects of motorized use of plowed roads on: 1) mortality caused by collisions – adverse,

negligible, and short term on bald eagles and grizzly bears; adverse, minor, and short term

on wolves; no known effect to date on lynx; and 2) displacement from preferred habitats –

adverse, negligible, and short term on bald eagles, no effect on grizzly bears; no known

effect to date on wolves and lynx. May decrease impacts to wolves and lynx relative to

alternative A due to the elimination of wheeled vehicles from Colter Bay to Flagg Ranch.

Otherwise, effects are generally the same as alternative A.

• Effects of nonmotorized use of groomed and designated ungroomed routes on displacement

from preferred habitats – adverse, negligible, and short term on bald eagles; no effect on

grizzly bears; no known effect to date on wolves and lynx. Same as alternative A.

• Effects of unregulated backcountry nonmotorized use on displacement from preferred

habitats – adverse, minor, and short term on bald eagles; adverse, negligible, and short term

on grizzly bears; adverse, minor, and short term on wolves; no known effect to date on

lynx. Effects decrease relative to alternative A due to restrictions on backcountry travel in

both parks. Restrictions may also mitigate any potential grizzly bear-human conflicts

associated with the early opening date of the parks.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

420

• Effects of the presence and use of winter support facilities on displacement – no affect on

bald eagles; adverse, negligible, and short term on grizzly bears, with mitigation; adverse,

minor, and short term on wolves; no effects on lynx. Effects are the same as alternative A.

Species of Special Concern

• Effects of groomed roads and trails on 1) animal movements – no known effect on

wolverines; adverse, negligible, and short term on fishers and martens; no effect on otters,

swans, reptiles, amphibians, and fish; 2) foraging activities – adverse, negligible, and short

term on marten; no effect on the other species; and 3) subnivian prey availability —

adverse, negligible, and short term on marten; no effect on the other species. Effects are

reduced relative to alternative A in GTNP.

• Effects of motorized oversnow use of groomed and ungroomed roads and trails on

displacement – no known effect on wolverine; adverse, negligible, and short term on

fishers and marten; no effect on otters, reptiles, amphibians, and fish; adverse, minor, and

short term on swans. Effect is decreased relative to alternative A due to the elimination of

snowmobiles.

• Effects of plowed roads on animal movements – no known effect on wolverines, fishers,

martens; no effect on otters, swans, reptiles, amphibians, fish. Same as alternative A.

• Effects of motorized use of plowed roads on displacement from preferred habitats: 1)

adverse, negligible, and short term on wolverines, fishers, and martens; no effect on otters,

swans, reptiles, amphibians, and fish; and 2) mortality from collisions — adverse,

negligible, and short term on otters and martens; no effect to date on other species. Same

as alternative A. Impacts may be decreased relative to alternative A due to the elimination

of wheeled—vehicles from Colter Bay to Flagg Ranch.

• Effects of nonmotorized use of groomed and designated ungroomed routes on displacement

from preferred habitats – no effect on wolverines; no known effect on fishers, martens, and

otters; adverse, minor, and short term on swans; adverse, negligible, and short term on

sagebrush lizard no effect on rubber boa, amphibians, and fish. Same as alternative A.

• Effects of unregulated backcountry nonmotorized use on displacement from preferred

habitats – adverse, negligible, short term on wolverines and sagebrush lizard; no known

effect on fishers, martens, and otters; adverse, minor, and short term on swans; no effect on

rubber boa, amphibians, and fish. Effects decrease relative to alternative A due to

restrictions on backcountry travel in all parks. Wolverines may benefit from bighorn sheep

closures in GTNP.

• Effects of the presence and use of winter support facilities on displacement of potential

prey (carcass) availability – adverse, minor, short term on wolverines, fishers, and martens;

no effect on swans, rubber boa, amphibians, and fish; no known effect on otters; adverse,

minor, and short term on sagebrush lizard. Same as alternative A.

Mitigation

• Grizzly bear abundance, distribution and habitat selection, including the location of dens

would continue to be assessed. The information obtained will assist park managers in

protecting important habitats and planning recreational activities that minimize disturbance

to bears.

• Snow track surveys for carnivores, including lynx, on both groomed and ungroomed routes

would be conducted.

• Use of groomed, ungroomed, and plowed surfaces by bison and other ungulates would

continue to be monitored.
IMPACTS OF IMPLEMENTING ALTERNATIVE G — THE PREFERRED ALTERNATIVE

421

Effects on Natural Soundscape

Audibility analysis — combined effects of all wheeled and oversnow vehicles

Table 141 presents the acres of park land by road segment where any wheeled or

oversnow vehicle noise would be audible under the two background conditions,

“average” and “quiet,” as defined in the Assumptions and Methodologies section of this

chapter. For each background condition, acreage is presented for three categories of

audibility: (1) audible for any amount of time (labeled “audible at all”); (2) audible for

10% of the time or more; and (3) audible for 50% of the time or more. Appendix M

contains tables with distances to audibility for each segment for each alternative.

Alternative G features no motorized vehicles of any type on Jackson Lake and Teton

Park Road in GTNP. It also replaces snowmobiles with snowcoaches in YNP, and

replaces snowmobiles and wheeled vehicles with snowcoaches from Colter Bay to Flagg

Ranch and on the Grassy Lake Road.

The results for alternative G show that for the “average” background sound level

condition, wheeled or oversnow vehicles would be audible to some degree on more than

178,000 acres in the three park units. On more than 74,000 of those acres, wheeled or

oversnow vehicles would be audible for at least 10% of the time during the day. For

nearly 13,000 of those acres, they would be audible for at least half of the time during the

day. These acreage totals increase by 12% for the “audible at all” category, 27% for the

“audible 10% or more” category, and 9% for the “audible for 50% of the time or more”

category for the “quiet” background conditions.

The segment from Moran Junction to the South Entrance of GTNP, which carries a great

deal of wheeled-vehicle traffic unrelated to the alternatives, contributes the greatest to the

total acreage values for all three audibility categories. These amounts remain almost

constant for all of the alternatives.

The plowed road from Mammoth to the YNP Northeast Entrance is a major contributor

to the “audible at all” acreage (and, to a lesser extent, “audible 10% or more”), which

remains virtually unchanged across all of the alternatives.

Compared to the no action alternative, there are increases in acreage for the “audible at

all” categories for all of the YNP road segments using snowcoaches only due to the long

distances to audibility for the Bombardier Snowcoaches as discussed under the Effects

Common to All Alternatives section of this chapter. Likewise, there is nearly a doubling

in acreage for the Flagg Ranch-Colter Bay segment. However, these increases are more

than compensated for by the elimination of oversnow vehicles on Jackson Lake and

Teton Park Road, leading to the overall reduction in acreage.

For the “audible for 10% of the time or more” categories, the acreage compared to the no

action alternative increases for some YNP segments and decreases for others.
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ENVIRONMENTAL CONSEQUENCES

422

For the “audible for 50% of the time or more” categories, there are major reductions in

acreage for the YNP West Entrance to Madison, Madison to Old Faithful, and West

Thumb to Flagg Ranch segments, due to the reduction in total vehicular traffic, in

addition to those segments where oversnow vehicles would be eliminated.

Table 141. Acres of park land affected by vehicle audibility for alternative G.

With Average Background

Conditions

With Quiet Background

Conditions

Road Segment Miles

Audible

at all

Audible

10% of the

time or

more

Audible

50% of the

time or

more

Audible

at all

Audible

10% of

the time

or more

Audible

50% of

the time

or more

1. Mammoth to Northeast Entrance 47 16,126 5,445 0 16,822 6,342 0

2. Mammoth to Norris 21 11,671 649 0 12,734 1,225 0

3. West Entrance to Madison 14 11,129 7,049 433 12,487 8,128 556

4. Madison to Norris 14 9,075 4,913 0 10,275 6,002 0

5. Norris to Canyon Village 12 5,740 1,031 0 6,637 2,518 0

6. Canyon Village to Fishing Bridge 16 10,883 4,433 0 12,233 5,521 0

7. Fishing Bridge to East Entrance 27 14,805 0 0 16,100 0 0

8. Fishing Bridge to West Thumb 21 17,671 10,032 0 20,423 12,495 0

9. Madison to Old Faithful 16 13,393 8,573 870 15,098 9,746 1,170

10. Old Faithful to West Thumb 17 10,207 4,822 0 11,549 5,918 0

11. West Thumb to Flagg Ranch 24 14,008 3,926 0 16,141 7,618 0

12. Grassy Lake Road 7.6 2,122 0 0 2,376 0 0

13. Flagg Ranch to Colter Bay 15.6 13,437 6,808 0 15,405 9,723 0

14. Colter Bay to Moran Junction 10.2 4,579 1,825 0 4,926 2,040 0

15. Moran Junction to East Entrance 2 1,225 753 490 1,319 863 535

16. Moran Junction to South Entrance 26 21,714 14,536 11,123 23,842 16,922 11,825

17. Teton Park Road 15 No Veh. No Veh. No Veh. No Veh. No Veh. No Veh.

18. Moose-Wilson Road 2.5 659 0 0 695 0 0

19. Antelope Flats Snowmobile Route -- No Veh. No Veh. No Veh. No Veh. No Veh. No Veh.

20. Jackson Lake 9.7 No Veh. No Veh. No Veh. No Veh. No Veh. No Veh.

TOTAL 178,445 74,795 12,916 199,063 95,060 14,087

Average sound level analysis

To give a sense of the effect of the number of oversnow or wheeled vehicles on a road

segment, and their speed and sound level, Table 142 shows the computed hourly

equivalent or “average” sound level (Leq) over the daytime period. Levels are shown for

each road segment at two distances, 100 feet and 4,000 feet, and for both open and

forested terrain. These hourly Leq values do not have the background sound level added

in to them. Also, they cannot be compared against the background levels to assess

audibility, because Leq represents a long-term average of both quiet and loud moments.
IMPACTS OF IMPLEMENTING ALTERNATIVE G — THE PREFERRED ALTERNATIVE

423

The hourly Leq at 100 feet are highest for the West Entrance to Madison and Madison to

Old Faithful segments. The Leq are reduced substantially (7 dB to 8 dB) compared to

alternative A for the YNP road segments where the snowmobiles would be replaced with

snowcoaches. At 4,000 feet away, the Leq are also highest for the West Entrance to

Madison and Madison to Old Faithful segments, as well as the segments from Moran

Junction to both the East Entrance and the South Entrance of GTNP.

Table 142. Average hourly Leq from wheeled and oversnow vehicle noise at two distances

to each road segment for alternative G.

Leq at distance (dBA)

Open Terrain Forested Terrain

Road Segment 100 feet 4,000 feet 100 feet 4,000 feet

1. Mammoth to Northeast Entrance 35 2 33 0

2. Mammoth to Norris 42 6 40 0

3. West Entrance to Madison 49 15 47 7

4. Madison to Norris 46 12 44 4

5. Norris to Canyon Village 44 10 43 2

6. Canyon Village to Fishing Bridge 43 9 42 1

7. Fishing Bridge to East Entrance 36 2 35 0

8. Fishing Bridge to West Thumb 43 9 41 1

9. Madison to Old Faithful 49 15 47 7

10. Old Faithful to West Thumb 45 11 43 3

11. West Thumb to Flagg Ranch 44 10 42 2

12. Grassy Lake Road 42 2 41 0

13. Flagg Ranch to Colter Bay 44 10 42 2

14. Colter Bay to Moran Junction 40 7 38 0

15. Moran Junction to East Entrance 47 13 45 5

16. Moran Junction to South Entrance 46 14 44 6

17. Teton Park Road No Veh. No Veh. No Veh. No Veh.

18. Moose-Wilson Road 24 0 22 0

19. Antelope Flats Snowmobile Route No Veh No Veh No Veh No Veh.

20. Jackson Lake No Veh No Veh No Veh No Veh.

Conclusion

Alternative G impacts 97% to 98% of the acreage impacted by the no action alternative

for the “audible at all” categories, the second highest after alternative C. Increases in

acreage for the YNP and GTNP road segments using only snowcoaches are more than

compensated for by the elimination of oversnow vehicles in all of GTNP except the

Flagg Ranch to Colter Bay and Grassy Lake Road segments.

Alternative G impacts 79% and 89% of the no action acreage for the “audible 10% of the

time or more” categories for the “average” and “quiet” background conditions,
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

424

respectively. These percentages are the third highest among the alternatives for the

“average” background and highest for the “quiet” background.

For the “audible 50% or more” categories, alternative G impacts only 53% to 55% of the

acreage for the no action alternative. These reductions are the greatest among the

alternatives, and are due to the exclusive use of snowcoaches in YNP.

The contributions to the Leq are reduced to zero for those road segments where vehicular

travel of all types is eliminated, and are substantially reduced for those segments where

snowcoaches replace snowmobiles.

Effects on Cultural Resources

The effects on cultural resources would be the same as described in alternative B.

Conclusion

None of the actions described would adversely impact cultural resources.

Effects on Visitor Access and Circulation

Access

Yellowstone National Park. Overall, access to park resources would not be affected by

this alternative, although visitors would be required to change their mode of motorized

travel to these resources from snowmobile to snowcoach.

Grand Teton National Park and the Parkway. Under this alternative, access to Flagg

Ranch would be closed to wheeled vehicles and snowmobiles in the winter use season.

Access to Flagg Ranch would be limited to snowcoach. Access to other areas of the park

would remain, although some limited changes in mode of travel would occur.

A reasonably foreseeable distribution of vehicle use as a consequence of this alternative

is depicted in the following table. Since the parks would be closed to snowmobiles there

would be a 100% decrease in snowmobile vehicle-miles traveled in the three park units.

Because snowcoaches would provide motorized access at current visitation levels to

YNP’s interior, from Colter Bay to Flagg Ranch and Flagg Ranch to the west boundary

of the Parkway, there would be an increase of 723% in snowcoach-miles traveled. Daily

wheeled-vehicle-miles traveled in this scenario would decrease by about 3%.
IMPACTS OF IMPLEMENTING ALTERNATIVE G — THE PREFERRED ALTERNATIVE

425

Table 143. Alternative G motorized use.

Average Daily Vehicle Use January-February

Road Segment Autos Vans Snowcoaches Snowmobiles Buses

Mammoth to Northeast Entrance No change from current condition

Mammoth to Norris 0 0 8 0 0

West Entrance to Madison 0 0 88 0 0

Madison to Norris 0 0 40 0 0

Norris to Canyon Village 0 0 30 0 0

Canyon Village to Fishing Bridge 0 0 24 0 0

Fishing Bridge to East Entrance 0 0 5 0 0

Fishing Bridge to West Thumb 0 0 20 0 0

Madison to Old Faithful 0 0 80 0 0

Old Faithful to West Thumb 0 0 34 0 0

West Thumb to Flagg Ranch 0 0 29 0 0

Grassy Lake Road 0 0 4 0 0

Flagg Ranch to Colter Bay 0 0 29 0 0

Colter Bay to Moran Junction 190 10 0 0 1

Moran Junction to East Entrance 560 28 0 0 2

Moran Junction to South Entrance No change from current condition

Teton Park Road 0 0 0 0 0

Moose-Wilson Road 5 0 0 0 0

Antelope Flats Snowmobile Route No change from current condition

Concession Services

Present concessions affected in this alternative would be all those permitted to run

snowmobile guided tours or provide snowmobile rentals (under concession contracts) for

use in the parks. This would adversely affect permittees or concessioners and their

employees at all gateways and destinations in the parks by removing the source of winter

income associated with this activity.

Oversnow tour and transportation services from all affected locations would need to be

developed or enhanced in order to meet visitor needs in this alternative. Approximately

180-200 snowcoaches would be necessary to accommodate today’s use levels. This

includes snowcoach access to and from the East Entrance of YNP once safer and more

feasible coaches are available. Since the availability of access does not change, only the

mode, concession operations would have the opportunity to adapt to the change while

still providing visitor services to and in the parks.

At Old Faithful, the logistics of moving people, fuel, supplies, or garbage would remain

dependent on oversnow transport. Storage of material in the park’s interior would be the

same as at present.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

426

Concessions and services offered at Flagg Ranch in the Parkway, would be affected by

not plowing the highway north of Colter Bay, and by eliminating snowmobile access

from Idaho via the Grassy Lake Road. NPS-managed snowcoach access from Idaho

would be allowed. The segment connecting Colter Bay and Flagg Ranch would be

accessible via NPS managed (concession) snowcoach only. Instead of wheeled-vehicle

access, most employees and clients would travel to and from the ranch by snowcoach.

Flagg Ranch would be snowbound, offering a more specialized experience than at

present – similar to Old Faithful. Its business focus would need to support and capitalize

on nonmotorized winter recreation, as would Old Faithful. This change would entail

operational changes and higher expenses for the concessioner in terms of moving

supplies and employees, and providing winter storage space.

The time available under this alternative for business adaptation is three years, when all

snowmobile access would be terminated in the winter 2003-2004.

The implementation of any alternative that might make substantial changes affecting a

concessioner would require negotiation between the NPS and the concessioner or be

deferred until a new concessions contract is awarded.

Conclusion

Negligible impacts to park access in all three parks would occur because access is not

altered, only the mode of travel is changed. Minor adverse impacts would occur in

GTNP because all motorized use on Jackson Lake is eliminated.

Effects on Visitor Experience — Yellowstone National Park

The amount and type of visitor opportunities offered in YNP under alternative G are

provided in Table 144.

Table 144. YNP Visitor opportunities available under alternative G.

Opportunities

Miles

or

Areas

Increase/

Decrease Length of Season Other

Groomed motorized route 0 -184 Mid-December to Mid-March Late night closure

Groomed motorized route,

snowcoach only

184 0 Mid-December to Mid-March Late night closure

Groomed motorized trail 0 0 Mid-December to Mid-March Late night closure

Plowed route 76 0 Mid-December to Mid-March Late night closure

Groomed nonmotorized 37 0 Mid-December to Mid-March Late night closure

Warming huts 7 +1 Mid-December to Mid-March Late night closure

Backcountry 2.2

million

acres

0 Cont inge nt on snowf a lli n

nor t he r n por ti on of pa r k

 None
IMPACTS OF IMPLEMENTING ALTERNATIVE G — THE PREFERRED ALTERNATIVE

427

Visitor Satisfaction and Experience

Opportunities to view wildlife. Opportunities to view wildlife would not decrease

under this alternative because the same level of oversnow visitor access would be

provided. However, because visitors riding on snowcoaches would be traveling in

groups, wildlife viewing would rarely be a solitary or an individualized experience. If

wildlife habituates to the new travel patterns of the snowcoach, wildlife viewing could be

improved. Because of the required use of mass transportation visitors would not

experience the personal freedom to stop and view wildlife at will.44

Opportunities to view scenery. Opportunities to view scenery would not decrease

under this alternative because the same level of oversnow visitor access would be

provided. However, the nature of the viewing experience for motorized access would

change substantially. Visitors who find the personal freedom to stop and view scenery, at

will, essential to their park experience would be adversely affected by this alternative.44

(see discussion under access to winter experiences below).

Safety (the safe behavior of others). Snowcoach-only travel would eliminate the risk of

snowmobile accidents and snowmobile/skier conflicts. The general decrease in vehicle

miles traveled would necessarily reduce the likelihood of motorized vehicle accidents. In

addition there were no large mammals hit or killed by busses or snowcoaches in YNP

from 1989 to 1998 (Gunther et al. 1998). Wildlife and snowmobile collisions often result

in human injury. Alternative G would result in moderate to major beneficial

improvements to visitor safety.

Safety concerns regarding avalanches for both motorized and nonmotorized users would

remain the same as alternative A.

Quality of the groomed surface. Both positive and negative effects to the groomed

surface would occur under this alternative. The larger tracks of snowcoaches would

reduce the overall quality of the groomed surface. However, because the total number of

vehicles would be reduced, an improvement in groomed surface quality would be

expected.

The availability of access to winter activities or experiences. Oversnow mechanized

access would be maintained on all existing groomed routes. Snowcoaches generally

travel at lower speeds (about 30 mph to 35 mph) than snowmobiles (40 mph to 45 mph).

For visitors who travel from the South Entrance to Old Faithful the slower snowcoach

travel time combined with the additional oversnow mileage from Colter Bay would

require an additional one hour of travel time each way.

 

44 It is important to note that impromptu stops by snowcoaches to view scenery and wildlife are frequent

occurrences under current operations and there is no reason to assume that this situation would change.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

428

The removal of snowmobile access into the park would eliminate the current most

popular form of winter experience (more than 60% of users) resulting in major adverse

effects on snowmobile users.45

The late night closure from 11 P.M. to 6 A.M. would result in negligible adverse effects

due primarily to visitor inconvenience.

Availability of information. Same as alternative C.

Quiet and solitude. Under alternative G only snowcoaches that can meet strict sound

standards would be allowed in the parks. Initially reduction in sound emissions would be

moderate; however, as the bombardier snowcoaches, which produce higher sound levels,

are retrofitted or phased out, the opportunities to experience quiet will be greatly

improved. This alternative would result in major beneficial effects overtime, particularly

for nonmotorized users of the parks. Because of the mass transit requirement, options for

solitude would be limited for visitors who cannot physically ski or hike.

Backcountry users would be restricted to designated routes in important winter range.

This action would result in a higher rate of skier encounters in these areas and limit the

range of opportunities currently available to skiers, about 20% of all winter visitors

(Littlejohn 1996).

Clean air. Through the permitting process the NPS would require that all snowcoaches

meet the highest environmental standards possible for commercially produced mass

transit oversnow vehicles. Currently this vehicle is the mat track conversion van. The

reductions in vehicle emissions would provide major beneficial improvements in

opportunities to experience clean air in YNP.

Conclusion

The reduction in emissions and sound under this alternative would result in direct major

beneficial improvements to the experiences of park visitors. There would be a minor to

moderate beneficial impact on visitor experience due to increased availability of

information, interpretation, and winter programs. There would be no change relative to

alternative A in opportunities to view wildlife and scenery, except for backcountry skiers

who would experience a minor to moderate decrease in these opportunities in some areas.

There would be major beneficial changes relating to safety by eliminating the possibility

of snowmobile related motor vehicle accidents.

Under specific circumstances, the adaptive management provisions of this alternative

may result in area closures. If monitoring or scientific studies regarding winter visitor

 

45 Recent survey data collected by Duffield et al. (2000a) indicates that about 33.4% of non-resident winter

visitors would not return to YNP under snowcoach-only management. However, national and regional

survey respondents indicated that they favored snowcoach-only access (Duffield et al. 2000c). Similarly, a

review of public comment on the DEIS indicates an even split between those who favored snowmobile access

and those who favored snowcoach only access. For park visitors who favored snowcoach-only access

alternative G would have a positive effect.
IMPACTS OF IMPLEMENTING ALTERNATIVE G — THE PREFERRED ALTERNATIVE

429

use, natural resources, and other park values indicate that sections of the park must be

closed or certain uses restricted to protect park values (for example, snowmobiling or

backcountry skiing), some or all visitor experiences in the closure area would be

eliminated. These areas of closure would result in localized direct adverse impacts to

desired winter visitor experience. However, the long-term protection of these resources

would provide major benefits to the protection of desired visitor experiences park-wide.

The overall effect of this alternative on the winter visitor experience would be moderate

to major and beneficial. However, the elimination of snowmobiles would result in major

adverse impacts to the experiences of visitors in this user group. Currently this

represents 60% of all winter visitors to the park.

Effects on Visitor Experience — Grand Teton and the Parkway

The amount and type of visitor opportunities offered in GTNP under alternative G are

provided in Table 145.

Table 145. Visitor opportunities available under alternative G.

Opportunities

Miles

or

Areas

Increase/

Decrease Length of Season Other

Groomed motorized route 0 -18.2 December to April† Late night closure

Groomed motorized route,

snowcoach

29 25.8 December to April† Late night closure

Groomed motorized trail 0 -33.9 December to April† Late night closure

Plowed road 83.4 -16.6 December to April† Late night closure

Ungroomed motorized

trail or area

0 -35.6 December to April† Late night closure

Groomed nonmotorized 0 0 December to April† Late night closure

Ungroomed nonmotorized

trail or area

27.4 1.0 December to April† Late night closure

Warming huts/interpretive

centers

5 3 December to April† Late night closure

†Variable, dependent on snow conditions

Visitor Satisfaction and Experience

Opportunities to view wildlife. Same as in alternative B.

Opportunities to view scenery. With the elimination of snowmobile access, and no

wheeled-vehicle access north of Colter Bay, there would be fewer opportunities to view

scenery by auto and snowmobile. Scenery would be viewed in this area from a

snowcoach operating from Colter Bay north to YNP and Flagg Ranch west to Idaho.

Safety (the safe behavior of others). The CDST would be eliminated through GTNP

and the Parkway, except for mass transit from Colter Bay to YNP and the west Parkway

boundary. This would enhance safety for other nonmotorized uses.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

430

Quality of the groomed surface. Oversnow motorized uses would be eliminated except

for snowcoaches. Snowcoaches would operate on a groomed route from Colter Bay into

YNP and to the west Parkway boundary.

The availability of access to winter activities or experiences. Access to motorized

winter experiences would be decreased except for snowcoaches operating from Colter

Bay into YNP and to the west Parkway boundary. There would be a loss of ice fishing

opportunities via snowmachine on Jackson Lake. The exclusion of motorized travel from

the Lake would also result in limited access to Webb Canyon and other backcountry

areas. However nonmotorized use on the Lake would be enhanced. Under this

alternative skiing on the groomed surface of the roadway north of Moran Junction would

also be available. These actions would particularly benefit local residents who indicated

that skiing in the park was their favorite activity (Teton County 1998). However,

because of the elimination of wheeled access to Flagg Ranch, park visitors who wish to

ski in areas between Moran Junction and Flagg Ranch may (depending on distance)

require a snowcoach shuttle for transport.

Availability of information. Same as in alternative D.

Quiet and solitude. With elimination of snowmobile and snowplane use, opportunities

for quiet and solitude would be enhanced. The major benefit of this would accrue to

nonmotorized uses. There would be a lost opportunity for snowmobilers who are seeking

this experience.

Clean air. With elimination of snowmobile use, a major source of pollution would be

eliminated. The opportunity to experience clean air would be greatly enhanced under this

alternative.

Conclusion

Minor adverse to negligible impacts on visitor experience relating to wildlife and scenery

viewing would occur because of the elimination of motorized travel on the frozen surface

of Jackson Lake. Opportunities to view wildlife would be improved for nonmotorized

users of these areas. There would be major beneficial changes relating to safety by

eliminating the possibility of snowmobile-related motor vehicle accidents, and wheeledvehicle accidents on the road segment from Colter Bay to Flagg Ranch. Improving

groomed surfaces would be moderately beneficial for snowcoach use and occupant

safety. Overall, there would be a major adverse impact on the availability of access for

those who wish to ride snowmobiles or snowplanes. There would be a minor to moderate

beneficial impact to visitor experience due to increased availability of information,

interpretation, and winter programs. There would be a major beneficial impact relative to

opportunities for quiet and solitude. Opportunities to appreciate clean air would be

greatly improved. Where oversnow motorized use occurs, via snowcoach, quiet and

clean air would be facilitated by improved motorized technology.
DIRECT, INDIRECT, AND CUMULATIVE EFFECTS ON ADJACENT LANDS

431

The adaptive management provisions of this alternative require that if monitoring or

scientific studies regarding winter visitor use, natural resources and other park values

indicate that sections of the park must be closed or certain uses (for example,

snowmobiling or backcountry skiing) restricted to protect these values, some or all visitor

experiences currently afforded in the area of closure would be eliminated (see Appendix

L, Adaptive Management). These areas of closure would result in direct and localized

adverse impacts to desired winter visitor experience. However, the long-term protection

of these resources would provide major benefits to the protection of desired visitor

experiences park-wide.

DIRECT, INDIRECT, AND CUMULATIVE EFFECTS ON ADJACENT

LANDS

Potential effects on lands within the GYA other than the three national park units is

discussed in this section. The US Forest Service (USFS); the States of Wyoming,

Montana, and Idaho; and five counties surrounding the park units (all cooperating

agencies in this EIS, see Chapter I and Appendix A) provided information for effects

analysis in this section. Since the potential for impacts on adjacent lands (apart from

economic impacts) is primarily due to possible displacement of winter recreation use

from the parks, an analysis of displacement introduces the disclosure of possible impacts.

Possible Conflicts with other Land Use Plans, Policies or Controls

CEQ Regulations (40 CFR 1502.16(c)) require discussion of possible conflicts between

the proposed action and objectives of land use plans, policies, or controls for the area

concerned. The cooperating agencies represent the jurisdictions in which such conflicts

might occur.

The chief concerns expressed by counties, as reflected in their areas of special expertise,

have to do with economic impacts of changes in park management (i.e., changes in

access or mode of access, and recreational opportunities available from each gateway).

Possible effects relating to loss of jobs or income in adjacent communities are disclosed

in the Socioeconomics section, Chapter IV. Such impacts would not affect local

government land use plans, other policies, or controls. This is largely because the

essential objectives of park management have not changed, but the means by which they

are to be attained could be altered. Teton County, Wyoming, expressed the desire that

GTNP would be consistent with the county’s new transportation plan. There is nothing

in any winter use plan alternative that changes the transportation interface with the

county. The park has initiated a separate study effort to review year-round transportation

needs in the park related to the county plan.

The States’ special expertise extended to resource analyses and recreation. They did not

indicate specific conflicts with any plan objectives. However, it can be assumed from

their comments that existing snowmobile use does not violate any state or federal

standards for air or water quality in or outside the parks. The State of Montana expressed

concerns about displaced recreational use and its potential impacts in the areas of safety
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

432

and wildlife management. These concerns are discussed in the Montana section below.

It can be inferred that if significant use is displaced to state jurisdictional lands, some

state objectives might not be met without further management. Wyoming’s chief

concerns had to do with possible declines in snowmobile tourism to the state through loss

of recreational opportunities, and related economic effects. It can be inferred that this

would conflict with state level tourism and recreation plan objectives. Similarly, Idaho

was concerned about impacts of possible displacement on recreational experience,

groomed trail quality, and grooming expense – possibly conflicting with local plans and

controls. The NPS has determined that there is no indication of any possible conflict

with county land use plans for any alternative because land allocations and basic

objectives in the parks would not change significantly.

All adjoining national forests have forest plans in effect, albeit in various stages of

revision. In The Winter Visitor Use Management Assessment (GYCC 1999), identifies

conflicts relating to winter use. Most conflicts include motorized use and related

infrastructure needs, wildlife impacts, and displacement of nonmotorized uses. The

assessment indicates that most such conflicts can be handled within the framework of

current forest plans, and the rest by forests during upcoming plan revisions. Considering

possible displacement of snowmobile use from the parks, the Bridger-Teton National

Forest indicates that increased use would destabilize a local balance between

nonmotorized and motorized use, and not meet plan objectives. Similarly, the CaribouTarghee National Forest states that increased use could exceed existing infrastructure and

result in the need to amend its new plan. The NPS interprets this conflict as follows for

all the forests involved. The forests have standards and guidelines that relate to quality

experiences within the spectrum of recreational opportunities. Some forests do not have

direction specific to winter use and recreation experience objectives. However, increased

use could cause facility capacities to be exceeded. It could also cause heavy trail use that

would not meet implied standards for quality use in a given management area. This

impact indicates the need for management action to bring use into conformance with the

plan – per the analysis in the Winter Visitor Use Management Assessment. The issue is

nearly moot since the National Forests indicate they are already at a threshold without

any park management changes.

Displacement of Snowmobile Recreation Use to Adjacent Lands

To perform additional effects analysis on forest lands, the USFS requested the NPS to

provide information on how use would change in the GYA as a result of each winter use

alternative for the parks. The NPS believes that such information is speculative. Many

different scenarios can be constructed for the same basic situation, for example, plowing

the road from West Yellowstone to Old Faithful. Additional permutations are added

when multiple alternatives must be dealt with, and even more when dealing with four

major gateways and several other access routes. A partial list of possible considerations

follows.
DIRECT, INDIRECT, AND CUMULATIVE EFFECTS ON ADJACENT LANDS

433

Many nonresident visitors that presently snowmobile in the parks also snowmobile on the

adjacent national forests during the same trip. If they cannot snowmobile in the park

from the gateway of their choice, they could:

• Continue to visit in future years but spend their time exclusively on national forest lands.

The net increase would be the one or two days per trip previously spent in the parks.

• Continue to visit in future years but spend their time on national forest lands as before, and

shorten their trip.

• Decline to come to the GYA and forego both national forest and park experiences.

• Continue to visit the GYA, spend as many days on the national forests as they do now and

visit the parks using another gateway or a different mode of transport.

Other considerations include the possibility of attracting new visitors with new

preferences, and different local users. Some people that have not come to the parks in the

past might choose to do so because of available mass transit opportunities, either on

plowed roads or groomed, oversnow routes. Such visitors could split their trips to spend

a day snowmobiling on the adjacent national forests.

Local snowmobilers would likely continue to use national forest lands as they have in the

past. If they can no longer use the parks as they have traditionally done from their local

community, they could:

• Enter the parks from another available gateway.

• Leave the region and go elsewhere for one to several trips over the season.

• Curtail their activity overall.

• Spend more time on local national forest lands.

• Visit national forest lands near of other gateways.

The development of a quantified scenario for future recreation use by alternative

is speculative. The NPS is in the position of providing a scenario of recreation

displacement. The scenario provided represents the most reasonable outcome based on

known preferences of current visitors through visitor surveys and current use at each park

gateway.46 Appendix J provides supporting computations for this displacement analysis,

including assumptions and methods. Conclusions are presented below.47

Alternative A

 It is assumed that the existing winter visitor use trends for a given area would continue.

 

46 CEQ Regulations at 40 CFR § 1502.22(b) address incomplete or unavailable information. Definitive

information about what people would do under a variety of scenarios cannot be obtained. The best available

data is from visitor surveys (Duffield, 2000) designed to ask pertinent questions of current winter visitors in

the parks. The results indicate what people may do under circumstances posed by key features of EIS

alternatives. These surveys are also the basis for impacts described in the socio-economic section and are

fully cited therein. Also see Appendix J.

47 As a cooperating agency, the USFS advocates the use of a worst-case scenario for displacement that might

occur in each alternative. The worst-case might be represented by the total amount of park visitation by

gateway or otherwise that would no longer be able to use that entrance. What those displaced visitors might

do is highly speculative.
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ENVIRONMENTAL CONSEQUENCES

434

Alternative B

• Based on survey responses of current winter visitors about what the visitor would do if the

road from West Yellowstone to Old Faithful was available for wheeled-vehicle mass transit

only, total visitation to the GYA by nonresidents (snowmobilers, snowcoach riders, and

skiers-snowshoers) would be reduced by 18.4%. Nonresidents account for nearly 80% of

total visitation in the parks. This reduction is a net change. It takes into account visitors

who said they would visit more often in this circumstance, and those who said they would

visit the same but shift their use to other areas of the GYA (e.g., from the parks to the

national forests). Total visitation to GYA national parks and adjacent national forests by

nonresidents could decrease by that amount. Visitation numbers are unavailable for

national forests. However, an wholesale decrease of nonresident visitors by 18.4% could

offset or exceed displacement of park use as estimated below (Ref. Economic impacts for

alternative B).48

• Considering a net decrease in the use of GYA national parks and adjacent national forest

lands in this alternative, about 6,700 trips (into the parks annually) are associated with

visitors who indicate they would visit the GYA at the same level, but would go to other

destinations. Based on the assumption that all the trips involve snowmobiling, a total of

about 75 snowmobile trips daily could be displaced to other available lands outside the

park near West Yellowstone, to other available areas in the parks, or to other adjacent

lands. This would be in addition to resident visitors (accounting for about 20% of park

visitation) who currently recreate on adjacent lands much of the time.

• In this alternative, interior roads of GTNP would be closed. Current use consists mostly of

local visitors, who could be displaced to the CDST into the Parkway and YNP, or to lands

on the Bridger Teton National Forest. About 3,600 snowmobile visits or 45 daily visits

could be displaced in this fashion.

Alternative C

• Similar to alternative B, this alternative would also result in a net 18.4% decrease in GYA

visitation by nonresidents. In addition early season plowing from the North Entrance could

displace about 1,600 visitors during February and 98 during March.

• For GTNP, plowing of the Moose-Wilson Road and Antelope Flats Roads would appear to

displace existing negligible use to within the park only. It would be shifted to the proposed

east side snowmobile trail.

Alternative D

• The winter use survey asked a question about what the visitor would do if the YNP’s East

Entrance were closed to snowmobiling, and the road from Colter Bay to Flagg Ranch was

not plowed. Based on the response, total visitation by winter visitors living outside the

five-county area to the GYA would be reduced by 4.4%. This reduction is a net change. It

takes into account visitors who said they would visit more often in this circumstance, and

those who said they would visit the same, but shift their use to other areas of the GYA

(e.g., from the parks to the national forests). Total visitation to GYA national parks and

adjacent national forests by nonresidents could decrease by that amount. Visitation

numbers are unavailable for national forests, but an across the board decrease of 4.4%

could offset displacement of park use as estimated below (Ref. Economic impacts for

alternative D). Overall, visitation in this alternative would be nearly the same as in

alternative A, and very little displacement would occur.

• Considering a net decrease in use in GYA national parks and on adjacent national forest

lands in this alternative, about 3,340 snowmobile visits are associated with visitors who

enter the park from YNP’s East Entrance. A total of about 40 snowmobile trips daily could

 

48 The worst-case scenario indicated by the USFS is that the total snowmobile visitation at the West Entrance

would be displaced to adjacent lands primarily in the Gallatin, Targhee or Beaverhead-Deerlodge National

Forests west of YNP. The average annual visitation is about 56,000 snowmobile passengers through the

West Entrance. This equates to an average daily number of snowmobile passengers over the season of about

620 distributed among the three forests.
DIRECT, INDIRECT, AND CUMULATIVE EFFECTS ON ADJACENT LANDS

435

be displaced to other available lands outside the park near Cody, Wyoming, such as the

Beartooth Plateau, or to other available park gateways.49

• In this alternative, interior roads of GTNP would be closed. Current use consists mostly of

local visitors who could be displaced to the CDST into the Parkway and YNP or to lands

on the Bridger Teton National Forest. About 3,600 snowmobile visits or 45 daily visits

could be displaced in this fashion.

Alternative E

• Foreseeable use distribution for YNP would be the same as in alternative A, with no net

change in visitation to the GYA and no displacement to national forests (Ref. Economic

impacts for alternative E).

• In this alternative, interior roads of GTNP would be closed. Current use consists mostly of

local visitors, who could be displaced to the Parkway north of Flagg Ranch and YNP, or to

lands on the Bridger Teton National Forest. About 3,600 snowmobile visits or 45 daily

visits could be displaced in this fashion.50

• The CDST trail would be closed through the park. A CDST shuttle service would be

provided. Snowmobiling would be allowed only on the Grassy Lake road and north of

Flagg Ranch. Most of the use that currently exists on this segment is in transit to Flagg

Ranch and YNP’s South Entrance. Since this opportunity would remain via shuttle or

personal vehicle, none of this use is expected to be displaced to adjacent lands.

Alternative F

• Based on survey responses of current winter visitors about what the visitor would do if the

roads from the West and North Entrances to Madison and Old Faithful were closed during

the winter, total visitation to the GYA by those who live outside the five-county area would

be reduced by 24.6%. Nonresident visitors account for about 80% of park visitation. This

reduction is a net change. It takes into account visitors who said they would visit more

often in this circumstance, and those who said they would visit the same, but shift their use

to other areas of the GYA (e.g., from the parks to the national forests). This means that

total visitation to GYA national parks and to adjacent national forests by nonresidents

could decrease by that amount. Visitation numbers are unavailable for national forests, but

an across the board decrease of 24.6% could offset or exceed displacement of park use as

estimated below (Ref. Economic impacts for alternative F).

• Considering a net decrease in use in GYA national parks and on adjacent national forest

lands in this alternative, about 4,000 snowmobile trips into the parks annually are

associated with visitors who indicate they would visit in the GYA the same amount, but

would go to other destinations. A total of about 50 snowmobile trips daily could be

displaced to other available lands outside the park near West Yellowstone, near Gardiner,

other available areas in the parks, or other adjacent lands. This would be in addition to

resident visitors (accounting for about 20% of park visitation) who currently recreate on

adjacent lands.51

• In this alternative, interior roads of GTNP would be closed. Current use consists mostly of

local visitors, who could be displaced to the Parkway north of Flagg Ranch and YNP, or to

lands on the Bridger Teton National Forest. About 3,600 snowmobile visits or 45 daily

visits could be displaced in this fashion.

• The CDST trail would be closed through the park. A CDST shuttle service would be

provided. Snowmobiling would be allowed only on the Grassy Lake road and north of

Flagg Ranch. Most of the use that currently exists on this segment is in transit to Flagg

Ranch and YNP’s South Entrance. Since this opportunity would remain via shuttle or

personal vehicle, none of this use is expected to be displaced to adjacent lands.

 

49 This would correspond with the Forest Service worst-case scenario.

50 This would correspond with the Forest Service worst-case scenario.

51 According to the USFS, the worst-case scenario is that the total snowmobile visitation at the West and

North Entrances would be displaced to adjacent lands in all the GYA National Forests. The average annual

visitation is about 57,500 snowmobile passengers through the West Entrance. This equates to an average of

about 675 snowmobile passengers a day to be distributed among the forests throughout the season.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

436

Alternative G

• Based on survey responses of current winter visitors about what the visitor would do if the

parks open for snowcoach access only, total visitation to the GYA by those who live

outside the five-county area would be reduced by 33.4%. Nonresident visitors account for

about 80% of park visitation. Nearly 60% of the visitors who snowmobiled on their trip

said they would visit the GYA less frequently. The 33.4% reduction is a net change. It

takes into account visitors who said they would visit more often in this circumstance, and

those who said they would visit the same, but shift their use to other areas of the GYA

(e.g., from the parks to the national forests). This means that total visitation to GYA

national parks and adjacent national forests by nonresidents could decrease by that amount.

Visitation numbers are unavailable for national forests, but an across the board decrease of

33.4% could offset or exceed displacement of park use as estimated below (Ref. Economic

impacts for alternative G).

• Considering a net decrease in use in GYA national parks and on adjacent national forest

lands in this alternative, about 5,230 snowmobile trips (into the parks annually) are

associated with visitors who indicate they would visit in the GYA the same amount, but

would go to other destinations. A total of about 65 snowmobile trips daily could be

displaced to other available lands outside the parks near all gateways. This would be in

addition to resident visitors (accounting for about 20% of park visitation) who currently

recreate on adjacent lands.52

Direct and Indirect Impacts on National Forest Lands

As described in the Chapter III, 51% of the GYA is in the national forest system. About

95% of the perimeter of the three parks abuts national forest lands. A high percentage of

the national forest system along this common boundary is in congressionally designated

wilderness, and inventoried or other roadless areas. There may be potential impacts to

wilderness and inventoried or other roadless areas from programmatic changes in

national park management that displaces oversnow motorized use.

Changes in management of the three parks that affect access by personal snowmobile

could result in changes in use on adjacent public lands, particularly national forest lands.

These lands are already heavily used by snowmobilers, and a number of existing and

potential conflicts relating to this use have been identified (GYCC 1999). The USFS

indicates that use is generally increasing on forest lands. From the standpoint of the three

parks, changes in recreation use on national forests would be an indirect effect of various

alternatives for park management.53 Impacts on national forest lands, wildlife, air, water,

or other resources from displaced recreation use are further removed from the source of

change. The difficulty in addressing these indirect and tertiary effects is that the impacts

associated with possible management changes in the parks are indistinguishable from the

impacts of currently increasing use on national forest lands. The most reasonable

approach is to consider increased use in the context of cumulative impacts because the

magnitude and type of impact from increased use is additive to the amount and type of

 

52 According to the USFS, the worst-case scenario is that the total snowmobile visitation in the three park

units would be displaced to adjacent lands on all GYA national forests. The average annual visitation is

about 84,000 snowmobile passengers through all Yellowstone entrances and within Grand Teton. This

equates to an average of about 1,000 snowmobile passengers distributed among the forests throughout the

season.

53 Indirect effect is defined as an effect removed in time or space from the activity that causes the impact.
DIRECT, INDIRECT, AND CUMULATIVE EFFECTS ON ADJACENT LANDS

437

impact from current snowmobile use. The USFS has not identified any other impact

sources, other than displaced winter visitors (snowmobiling and skiing), that would add

cumulatively to impacts on USFS lands adjacent to the parks.

Effects Common to all Alternatives

Impacts on the national forests likely would be initiated by a change in the pattern,

distribution, or amount of winter recreational use within the parks. The primary indirect

effect on the national forest would be a redistribution of the type, amount, and location of

use on adjacent forest lands. Other indirect effects may occur on wildlife, recreation

special use permittees, recreation quality, facility use, or program administration.

If “clean and quiet” motorized technology were required for parks, decreased sound or

emissions could occur on national forests as well. All alternatives except A and C

provide for some improvement in technology. The effects of new emission and noise

standards for oversnow vehicles could result in cleaner and quieter snowmachines on

nearby national forest lands. However, machines that do not meet the new emission and

noise standards are likely to continue operating on adjacent national forests, especially on

lands more distant from national park entrances, such as those near Lander, Dubois, or

Pinedale, Wyoming. Limiting backcountry use in the parks may increase this type of

winter use on national forests.

Potential Effects of Recreation Use Displacement on National Forest Lands

Alternative A

The best information source about existing use on National Forests is the 1999 Multiagency Assessment of Winter Visitor Use. The following descriptions for each GYA

forest are based on that assessment.54

Beaverhead-Deerlodge National Forest. The Beaverhead Deerlodge NF identified nine

areas of conflict involving winter use activities.55 The major issues relate to heavy use by

snowmobiles resulting in crowding (conflicts between snowmobilers), and in

displacement of skiers following conflict between those two user groups. Other issues

include use of elk winter range, nesting eagles, grizzly bears, wolverines, and motorized

trespass. The areas of conflict are shown on a map in the Winter Visitor Use Assessment

(GYCC 1999). The forest also notes that there are extensive areas offering backcountry

snowmobiling at very low to moderate use levels. Increasing motorized use levels have

displaced or are displacing nonmotorized users from the area. This is particularly evident

in more easily accessed day-use areas by people engaged in nonmotorized recreation

activities.56 An estimate of total snowmobile use on the forest is unavailable at this time.

 

54 A current analysis of existing conditions or impacts from winter use on national forest system lands,

including use statistics, is not available. Such information would be important in gauging the impact

associated with potential changes in recreation use resulting from the alternatives, using alternative A as the

baseline condition.

55 Greater Yellowstone Coordinating Committee (GYCC), Winter Visitor Use Management: A Multi-agency

Assessment. 1999. Pages 33-34.

56 Ibid. Appendix E.
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

438

Bridger-Teton National Forest. The Bridge-Teton NF identified 24 areas of conflict

involving winter use activities.57 The major issues relate to heavy use by snowmobiles

and cross-country skiers competing for trailhead space and suitable experiences,

especially in front country areas. The Shadow Mountain area balances motorized and

nonmotorized use precariously, such that any change on the east side of GTNP would

disrupt management. This is characterized as conflicts between users (crowding), as well

as between user groups. In the latter instance, displacement of skiers follows conflict

between motorized and nonmotorized users. In many of the identified issue areas,

conflicts are also identified with wintering ungulates, primarily elk and moose. The areas

of conflict are detailed and shown on a map in the Winter Visitor Use Assessment. The

forest also notes that extensive backcountry areas offer powder, uncrowded play areas,

and excellent opportunities for expert snowmobilers and skiers. On many routes,

motorized and nonmotorized uses coexist without problems, but concerns exist with

routes as crowding increases. The forest notes that there are places where additional

parking could be provided to access available terrain and disperse existing use. Use

trends indicate that winter recreation is on the increase everywhere on the forest.58 An

estimate of total snowmobile use on the forest is unavailable at this time.

Caribou-Targhee National Forests. Because activity in the sport is increasing,

motorized winter use is expected to increase. The annual change is expected to be a 4%

to 6% increase based on industry growth rates. There are potential effects on grizzly

bears and lynx from increased use. This may require future analysis and consultation by

the Targhee NF on specific use areas. In the 1999 assessment the Targhee NF identified

16 areas of conflict involving winter use activities.59 The major issues relate to heavy use

by snowmobiles, resulting in crowding, accidents, impacts on wildlife, and associated

with trespass into wilderness or wildlife closures. The areas of conflict are shown on a

map in the Winter Visitor Use Assessment (GYCC 1999). The forest also notes that, in

the past, the unequal distribution of uses has led to some displacement of nonmotorized

users by motorized users. Increased use in all areas has led to conflicts between users.

Those wishing a less crowded setting have been pushed further from trailheads and other

facilities to find the experiences they are seeking.60 The Targhee NF estimates current

snowmobile use, in concert with Fremont County, Idaho, to be about 300,000

snowmobiler days each year.

Custer National Forest. The Custer NF identified one area of conflict involving winter

use activities.61 This issue concerns wilderness trespass by snowmobiles, and is shown

on a map in the Winter Visitor Use Assessment (GYCC 1999). The forest also notes that

there are limited opportunities for oversnow motorized use due to difficult access, and

low or unreliable snow conditions in most years.62 It could be assumed that there are

 

57 Ibid. Appendix E.

58 Ibid. Pages 34-35.

59 Ibid. Appendix E.

60 Ibid. Pages 41-42.

61 Ibid. Appendix E.

62 Ibid. Page 37.
DIRECT, INDIRECT, AND CUMULATIVE EFFECTS ON ADJACENT LANDS

439

insufficient opportunities on the Custer NF to provide an attraction for displaced use. An

estimate of total snowmobile use on the forest is unavailable at this time. However, the

forest indicates that snowmobile use in the Cooke City area, the open basin near Crown

Butte, is less than 30,000 annually.

Gallatin National Forest. The Gallatin NF identified 24 areas of conflict involving

winter use activities.63 Similar to the Bridger-Teton NF, the major issues relate to heavy

use by snowmobiles and nonmotorized uses competing for trailhead space and suitable

experiences along trails and routes, and in open areas. This is characterized as conflicts

between users (crowding) as well as between user groups. Displacement of skiers often

follows conflict between motorized and nonmotorized users. In many of the identified

issue areas, conflicts are also identified with wintering ungulates, primarily elk. Several

areas are noted for potential conflicts with grizzly bears and eagles. Some areas are

characterized by wilderness trespass or entering wildlife closures by motorized vehicles.

The areas of conflict are shown on a map in the Winter Visitor Use Assessment (GYCC

1999). The forest also notes the need for change to provide a fairer mix of nonmotorized

uses where that category is in short supply or difficult for the public to access. The

needed management strategy is to maintain the quality of motorized opportunities while

protecting neighboring nonmotorized areas, wintering wildlife, and wilderness as use

continues to grow.64 The Gallatin NF provides estimates of snowmobile use on the

Hebgen Lake District and out of Cooke City at an average of 154,840 visitor days from

1995 to 1998.

Shoshone National Forest. The Shoshone NF notes that there is continued growth in

motorized winter use on the forest. Continued use conflicts related to snowmobiles are

as described in the Winter Visitor Use Assessment, accompanied by a continued need to

deal with conflicts using a variety of methods described therein. In the assessment the

forest identified 24 areas of conflict involving winter use activities.65 A variety of types

of conflicts are presented, most of which are described as of low to moderate intensity.

High levels of conflict are identified for Togwotee Pass and Brooks Lake involving

skiers and snowmobilers, crowding, safety, and wildlife impacts. The areas of conflict

are shown on a map in the Winter Visitor Use Assessment (GYCC 1999). The forest

also notes the need to manage growth in winter motorized use, and the demand for new

groomed or upgraded motorized trails (wider groomed surfaces). The forest states that it

could accommodate this need by grooming presently marked, ungroomed routes, or by

creating new routes in areas presently available for backcountry motorized experiences.66

An estimate of total snowmobile use on the forest is unavailable at this time.

 

63 Ibid. Appendix E.

64 Ibid. Pages 37-38.

65 Ibid. Appendix E.

66 Ibid. Page 40.
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ENVIRONMENTAL CONSEQUENCES

440

Alternative B

Impacts of this Alternative Noted as Common to all GYA National Forests. More

stringent standards for snowmobile emissions and noise in the parks would displace noncomplying snowmobiles to adjacent national forests in the short term. Long-term effects

of more stringent standards might result in development of quieter, cleaner snowmobiles

that would also be used on national forests.

Beaverhead-Deerlodge National Forest. The USFS indicates that increased use on the

forest might have the following effects. The quality of the snowmobiling experience

would be reduced for existing users who prefer a less-crowded experience. There could

be an increased impact to trails with resulting reduction in quality of experience or the

increased need for trail grooming. Increased pioneering into little used backcountry areas

could have corresponding increased impacts on wildlife such as lynx, wolverines, and

bald eagles. Increased impacts on wildlife might lead to restrictions on areas and seasons

of winter recreation use. Increased conflict between and within recreation user groups

could also occur.

However, nonresident visitor trips to the GYA are expected to decrease by 18.4% in this

alternative, so the impacts of increased use would likely not be realized from any change

in park management. The impacts of current local visitor use would be undiminished, or

it may increase to the extent local visitors no longer access the park by snowmobile. The

number of nonresidents who would no longer visit the area could more than offset the

increase in use by residents for a net decrease in use. The ratio of resident to nonresident

use currently experienced on the forest is not known. If nonresident use is a small

percentage of total use, then very little change could be expected in comparison to the

current condition.

Bridger-Teton National Forest. The USFS states that impacts would be the same as in

alternative A. Given the scenario based on the winter use survey, nonresident visitation

to the GYA could decrease by 18.4%. There is no definitive information about the ratio

of nonresident snowmobilers to resident snowmobilers, but it is likely that a high

percentage of use on the Bridger-Teton is from nonresidents. Therefore, in this

alternative, use on the forest could decline with overall visitation.

Caribou-Targhee National Forests. The USFS states that the Targhee NF would

experience more requests for outfitter and guide activities from operators in the West

Yellowstone and Jackson, Wyoming areas in this alternative. USFS states that there

would be an expected increase in use on some trails that are not presently heavily used;

this could force crowding on all trails in Fremont County, Idaho. Increasing use would

force a forest plan amendment to discuss additional use on lynx habitat. The forest

would expect an increase in the amount of traffic, currently traveling from Utah to

experience the park, to remain in the Island Park area. This would create a safety hazard

due to narrow winding trails found on the forest. Increased use may also lead to requests
DIRECT, INDIRECT, AND CUMULATIVE EFFECTS ON ADJACENT LANDS

441

to modify trails as an accommodation. Some destination users for the park could visit

Old Faithful and still snowmobile in the national forest as part of the overall experience.67

However, nonresident visitor trips to the GYA are expected to decrease by 18.4% in this

alternative, so the impacts of increased use would likely not be realized from any change

in park management. The impacts of current local visitor use would be undiminished, or

it may increase to the extent local visitors no longer access the park by snowmobile. The

number of nonresidents who would no longer visit the area could more than offset the

increase in use by residents for a net decrease in use. The ratio of resident to nonresident

use currently experienced on the forest is not known.

Custer National Forest. This alternative would minimally affect the Custer NF. While

plowing the West Entrance access could cause a shift in nonresident usage, the Beartooth

area or other parts of the Custer would be minimally affected. Since much of the current

use is from the resident population, use would not be expected to increase or decrease

significantly.

Gallatin National Forest. The Gallatin NF states that effects could be substantial,

creating potential impacts to wintering big game, threatened and endangered species, and

exacerbating already growing recreation health and safety issues, trespass into closed

areas, taxing existing infrastructure and heightening recreation user conflicts. However,

nonresident visitor trips to the GYA are expected to decrease by 18.4% in this alternative,

so the impacts of increased use would likely not be realized from any change in park

management. The impacts of current local visitor use would be undiminished, or it may

increase to the extent local visitors no longer access the park by snowmobile. The

number of nonresidents who would no longer visit the area could more than offset the

increase in use by residents for a net decrease in use. The ratio of resident to nonresident

use currently experienced on the forest is not known.68

Shoshone National Forest. Nonresident visitor trips to the GYA are expected to

decrease by 18.4% in this alternative, so the impacts of increased use would likely not be

realized from any change in park management. The impacts of current local visitor use

would be unchanged because access to the parks from the Shoshone NF would not

change. That is, access would remain through YNP’s East Entrance, the CDST and

YNP’s South Entrance. The number of nonresidents who would no longer visit the area

could more than offset the local redistribution of use by residents for an overall net

decrease in use. There is a potential for users who could not use the West Entrance to

come to the East Entrance instead. This redistribution would not affect forest lands. The

potential for redistribution of nonresident use to the southern portion of the Shoshone NF,

 

67 General public use of the plowed road by personal vehicle would not be available as part of this alternative.

68 The worst-case scenario would be that in which all West Entrance snowmobile users would continue to

come to the GYA but not enter the parks at any other gateway and use only adjacent lands. The average

annual access by snowmobiles through the West Entrance is about 56,000 snowmobile passengers. Over a

season, this equates to about 620 snowmobile passengers per day distributed possibly among the Gallatin,

Targhee and Beaverhead-Deerlodge forests on the west side of Yellowstone.
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thus increasing use on Togwotee Pass, is possible but not likely because of the overall

decrease in use by nonresidents.69 Should there be a local redistribution of this type, the

effect would be to exacerbate the existing motorized use conflicts in that area which

relate primarily to snowmobile crowding and displacement of nonmotorized users as

shown in alternative A.

Alternative C

Impacts of this Alternative noted as common to all GYA Forests. Potential

displacement of recreation use from the parks is very much the same as in alternative B.

That is, an overall reduction of nonresident visitor use to the GYA of 18.4% is expected

based on the survey of current winter visitors. The USFS states that in this alternative,

the elimination of the loop route in YNP in mid-February (from an early season plowing)

could inordinately affect the forests by displacing motorized use to them during times

that are critical for wildlife (spring bear emergence, lynx, wolverines, nesting bald eagles,

and moose winter range).70 Any displaced use that causes local increases near denning

habitat for bears may be of concern during both the winter and the spring use period.

Beaverhead-Deerlodge National Forest. Effects of increased use on the forest could be

similar to those outlined for alternative B above.

Bridger-Teton National Forest. With respect to access into YNP and GTNP, this

alternative is not materially different from alternative B the impacts as noted in that

alternative would apply here as well. The USFS states that impacts would be the same as

in alternative A. Considering the scenario based on the winter use survey, nonresident

visitation to the GYA could decrease by 18.4%. There is no definitive information about

the ratio of nonresident snowmobilers to resident snowmobilers, but it is likely that a

high percentage of use on the Bridger-Teton NF is from nonresidents. Therefore, in this

alternative, use on the forest could decline with overall visitation.

The major difference in this alternative from current management in GTNP is the

proposed east side snowmobile trail between GTNP's south boundary and Moran. Use of

this trail could affect existing nonmotorized uses on the national forest east of the park.

However, existing access by passenger car to the Shadow Mountain trailhead would

remain the same as at present to facilitate multiple use access to national forests from the

park. Any significant use of the new snowmobile trail could displace cross-country

skiers from the Shadow Mountain area, one of the most popular ski trails in Jackson

Hole. The USFS states that this would not be compatible with forest objectives; the

 

69 There is no quantified estimate of total use on Togwotee Pass. The worst-case scenario is that a portion of

the 56000 annual snowmobile passengers no longer using the West Entrance would come to the Shoshone as

well as the other west GYA forests, and not reenter the parks.

70 NPS notes that there is no supporting information associated with this statement, and that it is a statement

contributed generically by most of the GYA forests. Considering that there is no recent forest data regarding

the current condition that would indicate any concern about present use on the forests regarding wolverines,

eagles or lynx, there appears to be a suggestion that only use displaced from the parks is of concern. It

should be noted that all forests also indicate that use is increasing on NF lands, such that without any changes

in park management there would still be a concern about such impacts.
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Bridger-Teton NF offers little opportunity for family skiing and easy terrain. Offered

areas (Cache Creek, Shadow Mountain, a few other places) are also used increasingly by

snowmobiles.

Caribou-Targhee National Forests. The Caribou-Targhee NF states that an increase in

the amount of traffic that currently travels from Utah to experience the park would in this

alternative (as in alternative B) remain in the Island Park area to continue the sport of

snowmobiling. Should this happen, it would create a safety hazard due to narrow

winding trails found on the forest. Increased use may also lead to requests to modify

trails to accommodate increased use. Due to the plowing of the roads in the park from

the north in the late season, an increase in the number of users from the eastern states

would be expected. Access to the West Yellowstone and Island Park area becomes easier

during the prime part of the season. With any local increase in use, the Ashton area of

the Targhee NF could expect more snowmobile traffic over the Ashton Flagg Ranch

road, past Mesa Falls to Island Park, as this would become the major access snowmobile

route coming from the east and terminating in West Yellowstone. Increased use over the

Flagg Ranch Road and expected late season snowmobile traffic coming through the park

from the eastern states may have effects on lynx habitat. With increases in local use, the

Targhee NF states that it could experience more requests for outfitter and guide activities

from operators in the West Yellowstone and the Jackson Hole areas. Use would be

expected to increase on some trails not presently heavily used. This could force all trails

to be crowded in Fremont County, Idaho. Increasing use would force a forest plan

amendment to discuss additional use on lynx and habitat.

Considering the scenario based on the winter use survey, nonresident visitation to the

GYA could decrease by 18.4% and the potential impacts described above would not

materialize since most are related to visitation from outside the GYA.

Custer National Forest. Impacts on the Custer NF would be the same as in alternative

B, in which there is a negligible change from the current management situation.

Gallatin National Forest. The impacts of alternative C would be the same as those

described in alternative B, with one exception. The USFS states that the late season

plowing from Mammoth to Madison could locally displace use to the Cooke City

vicinity. Given the scenario from the winter use survey responses, any such

displacement would primarily affect resident snowmobilers. The overall reduction of

nonresident visitors by 18.4% could offset any local redistribution of use.

Shoshone National Forest. Impacts on the Shoshone NF would be the same as in

alternative B, in which there is a negligible change from the current management

situation.

Alternative D

Beaverhead-Deerlodge National Forest. Since access to YNP from the north, west,

and south do not change from current management in this alternative, there would be no
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concerns about effects of increased use on the forest. The minimal amount of local

redistribution of use from the closed East Entrance is not likely to be displaced to the

Beaverhead-Deerlodge NF. The USFS states that prohibition of night use in the parks in

this alternative could increase night use on the Beaverhead-Deerlodge NF. Night use in

backcountry of the national forest would have a greater safety risk than night use on the

well-groomed and marked trails of the parks.71

Bridger-Teton National Forest. Since access to YNP from the north, west, and south

do not change from current management in this alternative, there would be no concerns

about effects of increased use on the forest. The minimal amount of local redistribution

of use from the closed East Entrance is not likely to be displaced to the Jackson,

Wyoming area except for the small portion of it that relates to nonresident visitors. The

USFS states a concern about redistribution of local skiing use by people who engage in

that activity by wheeled-vehicle access along the Colter Bay to Flagg Ranch road

segment. In this alternative, GTNP does not plow the road from Colter Bay to Flagg

Ranch. However, most of GTNP would be available for nonmotorized use without

motorized conflicts, and there are possibilities for facilitating nonmotorized use between

Colter Bay and Flagg Ranch using snowmobile or snowcoach shuttle access. There is no

expectation that any nonmotorized use would be displaced, or that it would be displaced

to adjacent lands.72

Access via motorized means to private inholdings and adjacent private and public lands

would be maintained along the eastern boundary of GTNP. For adjacent public lands,

this applies primarily to those on the east side of the park including access to Shadow

Mountain and access near the Triangle X Ranch. Maintenance of this access would not

affect the balance of motorized and nonmotorized use in the Shadow Mountain area. See

Actions and Assumptions Common to All Alternatives in this EIS.73

Caribou-Targhee National Forests. The USFS expects effects similar to the no action

alternative covering numbers of users. Prohibition of night use in the parks could

increase night use on the Island Park district, exacerbating existing problems.74

Custer National Forest. Closing the East Entrance could increase snowmobile use in

the Beartooth and Cooke City areas. Topographic features and wind blown areas in the

Beartooth Mountains on the Beartooth Ranger District currently limit the potential for

 

71 If night use presently occurs, and is a safety hazard, it is not reasonable to attribute this impact solely to

possible changes in park management.

72 The Forest Service states that most of the skiers in this area are coming from Jackson and their primary

destinations in the Colter-Flagg area are Colter Bay/Hermitage Point, Flagg Canyon, Huckleberry and

Polecat Hot Springs, and Huckleberry Mountain. Because the lookout and hot springs are primary

destinations, these skiers don’t have an alternative that would meet the same desires, so it’s hard to say where

they would be displaced to. If snowcoach transport were available and affordable, it would be possible to

reach trailheads in the Flagg Ranch area for skiing, and a few people who own snowmobiles would still be

able to access these areas.

73 It was not made clear in the DEIS that such access would be maintained.

74 If night use presently occurs, and is a safety hazard, it is not reasonable to attribute this impact solely to

possible changes in park management.
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445

even moderate increases in new snowmobile play use areas, however, use could increase

along existing trails. To the extent that the East Entrance use comes from nonresident

visitors, total visitation on the east side of YNP is most likely to decrease. This amount

is some percentage of the average annual 3,340 snowmobile trips, or 40 daily trips. To

the extent that this use is attributed to resident visitors, again something less than 40 daily

trips, this amount could be displaced to the Beartooth area.

Increased use of something less than 40 snowmobile visits per day along existing trails in

the Red Lodge and lower Stillwater River area, and especially in areas of the Custer NF

adjacent to Cooke City would be expected. The headwaters of the Stillwater River on the

Custer NF, near Cooke City would likely receive increased use, particularly the play area

associated with the open grassland basin near Crown Butte. Should all use from the East

Entrance be displaced to the Crown Butte area, with an estimated existing snowmobile

use of 30,000 (or less) round trips per year in the basin, this would be an increase of just

over 1%. This increase would be an upper bound on the estimate for reasons discussed

above. Snowmobile use is restricted to non-wilderness areas. Wilderness trespass by

snowmobile users is currently a problem that could increase with additional use in the

area.

Gallatin National Forest. Since access to YNP from the north, west, and south do not

change from current management in this alternative, there would be little concern about

effects of increased use on the forest. The minimal amount of local redistribution of use

from the closed East Entrance (less than 40 snowmobile trips per day on the average)

could be displaced to the Cooke City area, where parking and grooming infrastructure is

currently taxed. Additional use pressure at Cooke City could also exacerbate wilderness

trespass issues that have grown substantially in recent years. Prohibition of night use in

the parks could increase night use on Hebgen Lake district, exacerbating existing

problems.

Shoshone National Forest. The USFS is concerned that this alternative could close

Pahaska Lodge (located outside YNP’s East Entrance) during the winters. Pahaska

Lodge now has a considerable number of year-round employees, which allows it to

maintain a stable and conscientious work force. Forcing this operation to a summer-only

operation would cause considerable disruption for the owners and employees. The

Pahaska-East Entrance is also the location of the majority of Park County’s nordic skiing

trail system. Pahaska gets the majority of its overnight use from snowmobilers, those

starting at the East Entrance or those coming from the West Entrance to stay overnight

and returning. Without snowmobiler overnight lodging or rentals, there is a high

likelihood that the nordic opportunities in the Pahaska area would also close.

Lack of access through the East Entrance would likely displace a minimal amount (less

than 40 snowmobile trips per day) of motorized use to Cooke City, Sunlight Basin, and

the Beartooth Plateau, where conflicts presently exist or resource concerns have been

identified. Some use could also be displaced to the Bighorn NF where motorized
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recreation use has been increasing. It could also significantly affect the operation at

Pahaska Tepee Lodge (snowmobile rentals and winter stays), and other North Fork

lodges that have been gearing toward winter motorized use in recent years. East

Entrance motorized use cannot be relocated to the national forest in areas presently

accessible via these same lodge facilities due to the near presence of wilderness and the

lack of suitable snow and terrain.

Alternative E

Impacts of this Alternative noted as common to all GYA Forests. The USFS states

that there is a range of possible effects and outcomes associated with the adaptive

management alternative, and that this presents a challenge for determining the possible

effects on national forests.75 Given there is a potential for management changes in this

alternative due to adaptive management, the foreseeable impacts in alternative E would

be the same as in alternative A for YNP. Management changes in GTNP are evident in

the alternative description apart from possible future changes due to adaptive

management.

Beaverhead-Deerlodge National Forest. The impacts would be the same as in

alternative A. The effect of eliminating the CDST from GTNP’s East Entrance to Flagg

Ranch would not result in use redistribution that could affect the Beaverhead-Deerlodge

NF.

Bridger-Teton National Forest. Foreseeable use distribution for YNP would be the

same as in alternative A, with no net change in visitation to the GYA and no

displacement to national forests (Ref. Economic impacts for alternative E).

The USFS expresses concerns about local displacement of recreation use from changes in

motorized use opportunities within GTNP. In this alternative, interior roads of GTNP are

closed. Current use consists mostly of local visitors, who could be displaced to the

Parkway north of Flagg Ranch and Yellowstone, or to lands on the Bridger Teton NF.

About 3,600 snowmobile visits or 45 daily visits could be displaced in this fashion.76

The CDST trail is closed through the park except for provided shuttle service;

snowmobiling is allowed only on the Grassy Lake road and north of Flagg Ranch. Most

of the use that currently exists on this segment is in transit to Flagg Ranch and YNP’s

South Entrance. Since this opportunity remains via shuttle or personal vehicle, none of

this use is expected to be displaced to or remain on the Bridger-Teton NF. Average daily

use on the CDST coming from GTNP’s East Entrance is 24 snowmobiles (including

round trip use). Peak day use is 43 machines. There is no available estimate of total or

 

75 Some effects of this alternative would be disclosed by looking at effects in pieces of other alternatives.

However, there may be other sensitive areas that could now be identified, or would arise through future

monitoring where closures or other restrictions have not been anticipated. A worst-case assessment, shifting

significant amounts of use to national forests, raises secondary issues such as ungulate habitat or T&E

species, and burgeoning recreational user conflicts. The FS states that it is not sure what the consequences of

this would be.

76 This would correspond with the Forest Service worst-case scenario.
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447

daily use on Togwotee Pass, but it is reasonable to assume that 24 snowmobile trips per

day, should it remain on Togwotee, is not a significant percentage of daily use in that

area.77

Caribou-Targhee National Forests. Conditions would be the same as in alternative A.

Management in YNP is unchanged in the foreseeable future, and access through GTNP

and into Flagg Ranch from the west would not change. Changes in visitation, up or

down, are not anticipated, therefore, there would be no displacement effect to consider.

Custer National Forest. Conditions would be the same as in alternative A.

Management in YNP is unchanged in the foreseeable future, and access through GTNP

and into Flagg Ranch from the west would not affect the Custer NF. Changes in

visitation, up or down, are not anticipated, therefore, there would be no displacement

effect to consider.

Gallatin National Forest. Conditions would be the same as in alternative A.

Management in YNP is unchanged in the foreseeable future, and access through GTNP

and into Flagg Ranch from the west would not affect the Gallatin NF. Changes in

visitation, up or down, are not anticipated, therefore, there would be no displacement

effect to consider.

Shoshone National Forest. The forest notes no additional or specific impacts. See

effects for the Bridger-Teton NF, in which the forest is concerned about possible

increases in use on Togwotee Pass due to the closure of the CDST through GTNP.

Alternative F

Impacts of this Alternative noted as common to all GYA Forests. The USFS is

concerned that if the parks close to dispersed backcountry use (except on designated

routes) an inordinate effect on adjacent national forest wildlife habitat from displaced use

could occur. They state that with presently limited access for that type of use on forests,

except to areas that are generally closed for wildlife purposes, increased human-crucial

winter range habitat conflicts and increased conflicts between user groups would be

anticipated. Backcountry closures in alternative F for YNP could displace this type of

use. NPS estimates displacement of backcountry nonmotorized use to be about 840

visitors per year. Based on the winter use survey results, about 5% of these users would

or may continue to visit the GYA to engage in this use. In this alternative, using the

survey assumptions, an estimated 42 skiers annually would be displaced to surrounding

 

77 The FS is concerned about infrastructure (trailhead parking, restrooms, trail capacities) limitations on the

Bridger Teton and Shoshone over Togwotee pass and in other locations. Trailheads are already full and

people are parking on the highway margins. The FS is pursuing what opportunities exist to enlarge a few of

the parking areas, but this won’t meet the need if significant average amounts of use are displaced from the

park to adjacent lands. FS believes that this alternative would force many Togwotee Pass users to stay on the

forest rather than use a shuttle system to Flagg Ranch. FS states that users with their own machines or rentals

would be more likely to use the forest in the Togwotee area, or drive to Flagg and start their park trip there.

Because snow and trail conditions on the CDST in the park (especially around Moran) aren’t very good, FS

believes most users already use the forest because of better snow and more trails.
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national forests or to GTNP, since backcountry use would not be restricted there in this

alternative.

The USFS is concerned that if bison exit the park because of availability of groomed

routes, and if those routes are no longer available to the west and north where much of

the movement presently occurs, then there could be a significant movement of bison

along south and east routes onto national forests. With reference to the analysis of

alternative F on bison, most of the bison migration from YNP on the north and west does

not occur on groomed routes. Therefore, eliminating groomed routes would have little if

any impact on migration patterns.

Beaverhead-Deerlodge National Forest. The impacts of this alternative would not be

greatly different from those shown in alternatives B and C, except that nonresident visitor

trips to the GYA are expected to decrease by 24.6 % instead of 18.4% in this alternative.

Given this assumption, the impacts of increased use would be even less likely from any

change in park management.

Bridger-Teton National Forest. Nonresident visitor trips to the GYA are expected to

decrease by a net 24.6% in this alternative, accounting for visitors who said they would

shift their use to other areas in the GYA or would visit more. The impacts of current

resident visitor use on the forest would be undiminished. The local redistribution of use

by some nonresident snowmobilers who would continue to visit the GYA could continue

to access the parks via the South or East Entrances. This could be offset by an overall

decrease in nonresident visitor use to the area.78 Local redistribution, using the winter

survey results, show 50 snowmobile trips daily could remain in the West Yellowstone

and Gardiner areas, or access the parks through the South and East Entrances.

Considering total existing use in all areas, this would not be a significant displacement

impact in the Jackson area or on the Bridger-Teton NF.

Caribou-Targhee National Forests. Snowmobile use on the national forest would be

similar to alternatives B and C with implementation of this alternative. Nonresident

visitor trips to the GYA are expected to decrease by a net 24.6% in this alternative,

accounting for visitors who said they would shift their use to other areas in the GYA or

would visit more. The impacts of current resident visitor use on the forest would be

undiminished. Since much of visitation on this forest comes from nonresidents, it could

be expected that the decrease in GYA nonresident visitation would be absorbed largely

on the Targhee NF. Local redistribution, using the winter survey results, show 50

snowmobile trips daily could remain in the West Yellowstone and Gardiner areas, or

access the parks through the South and East Entrances (via Flagg Ranch and Afton).

 

78 FS is concerned that a great deal of additional use at South Entrance would engender additional

use in the Moran-Togwotee area. The worst-case scenario involves about 675 daily snowmobile

trips distributed to forest lands on the Gallatin, Targhee, Beaverhead-Deerlodge, or to the South

and East Entrances of Yellowstone with ancillary use occurring on the Custer, Shoshone and

Bridger-Teton.
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449

Considering total existing use in all areas, this would not be a significant displacement of

use to the Targhee NF, within the context of an overall decrease in nonresident use.

Custer National Forest. Snowmobile use on the national forest would be similar to

alternatives B and C with implementation of this alternative. Nonresident visitor trips to

the GYA are expected to decrease by a net 24.6% in this alternative, accounting for

visitors who said they would shift their use to other areas in the GYA or would visit

more. The impacts of current resident visitor use on the forest would be undiminished.

Local redistribution, using the winter survey results, show 50 snowmobile trips daily

could remain in the West Yellowstone and Gardiner areas, or access the parks through

the South and East Entrances. Considering total existing use in all areas, this would not

be a significant displacement of use to the Custer in the Beartooth and Cooke City areas.

Increased use of something less than 50 snowmobile visits per day in areas of the Custer

NF adjacent to Cooke City would be expected. The headwaters of the Stillwater River on

the Custer NF, near Cooke City would likely receive increased use, particularly the play

area associated with the open grassland basin near Crown Butte. Should all use from the

North and West Entrances be displaced to the Crown Butte area, with an estimated

existing snowmobile use of 30,000 (or less) round trips per year in the basin, this would

be an increase of between 1% and 2%. This increase would be an upper bound on the

estimate since nonresident use is more likely to decrease or go elsewhere in the GYA.

Snowmobile use is restricted to non-wilderness areas. Wilderness trespass by

snowmobile users is currently a problem that could increase with additional use in the

area.

Gallatin National Forest. Snowmobile use on the national forest would be similar to

alternatives B and C, except that nonresident visitor trips to the GYA would be expected

to decrease by a net 24.6% in this alternative instead of 18.4%. This would be a net

reduction, accounting for visitors who said they would shift their use to other areas in the

GYA or would visit more. The impacts of current resident visitor use on the forest would

be undiminished. Local redistribution, using the winter survey results, show 50

snowmobile trips daily could remain in the West Yellowstone and Gardiner areas, or

access the parks through the South and East Entrances. Considering total existing use in

all areas, and the overall decrease in nonresident visits to the GYA, this would not result

in a significant displacement of use to the Gallatin NF. If the displaced use were to come

to the Cooke City area of the Gallatin, it would represent less than 1% of the estimated

45,000 to 60,000 snowmobiles that annually use the area.79

 

79 Source: Ron Gardner, and Kimberly Schlenker, Gallatin N. F., April 6, 2000. FS is concerned that a great

deal of additional use would be displaced to the Gallatin. The worst-case scenario involves about 675 daily

snowmobile trips distributed to forest lands on the Gallatin, Targhee, Beaverhead-Deerlodge, or to the South

and East Entrances of Yellowstone. FS states that on the Gallatin, human-crucial winter range habitat

conflicts could be anticipated, with potential impacts to wintering big game, T&E species, and exacerbating

already growing recreation health and safety issues, trespass into closed areas, taxing existing infrastructure

and increasing recreation user conflicts.
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Shoshone National Forest. Nonresident visitor trips to the GYA are expected to

decrease by 24.6% in this alternative, so the impacts of increased use would likely not be

realized from any change in park management. The impacts of current local visitor use

would be unchanged because access to the parks from the Shoshone NF would not

change. Access would remain through YNP’s South and East Entrances. The number of

nonresidents who would no longer visit the area could more than offset the local

redistribution of use by residents for an overall net decrease in use. There is a potential

for users who could not use the West and North Entrances to come to the East Entrance

instead. This redistribution would not be expected to affect forest lands due to the lack of

available snowmobiling adjacent to it. The potential for redistribution of nonresident use

to the southern area of the Shoshone NF, increasing use on Togwotee Pass, is possible

but not likely because of the overall decrease in use by nonresidents.80 Should there be a

local redistribution of this type, the effect would be to exacerbate the existing motorized

use conflicts in that area which relate primarily to snowmobile crowding and

displacement of nonmotorized users as shown in alternative A.

Alternative G

Impacts of this Alternative noted as common to all GYA National Forests. An

overall reduction of nonresident visitor use to the GYA of 33.4% is expected based on

the survey of current winter visitors. This percent reduction is a net change. It takes into

account visitors who said they would visit more often in this circumstance, and those

who said they would visit the same, but shift their use to other areas of the GYA (e.g.,

from the parks to the national forests). This means that total visitation to GYA national

parks and to adjacent national forests by nonresidents could decrease by that amount.

Visitation numbers are unavailable for national forests, but an across the board decrease

of 33.4% could offset or exceed local displacement of park use. Within the context of an

overall decrease in nonresident use, there could be a redistribution of those nonresident

visitors who continue to come to the GYA. Based on survey results, this amounts to

about 65 snowmobile trips daily distributed among all the GYA forests. Considering

total existing use on GYA forests, this amount would appear to be insignificant.

The USFS is concerned that increased use on forests as a result of displaced park use

could inordinately affect the forests in areas and during times that are critical for wildlife

(spring bear emergence, lynx, wolverines, nesting bald eagles, moose winter range).81

 

80 There is no quantified estimate of total use on Togwotee Pass. The worst-case scenario is that a portion of

the 56,000 annual snowmobile passengers no longer using the West Entrance would come to the Shoshone as

well as the other west GYA forests, and not reenter the parks.

81 Considering that there is no recent forest data regarding the current condition that would indicate any

concern about present use on the forests regarding wolverines, eagles or lynx, there appears to be a

suggestion that only use displaced from the parks is of concern. It should be noted that all forests also

indicate that use is increasing on NF lands, such that without any changes in park management there would

still be a concern about such impacts.
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Any displaced use that causes local increases near denning habitat for bears may be of

concern during both the season and the spring use period.82

Beaverhead-Deerlodge National Forest. An overall decrease of 33.4% in nonresident

use of both park and forest lands in the GYA is expected based on the survey of current

winter visitors. In this event, there would be no net increase in use of the forest, and

quite possibly a decrease. The amount of use associated with local residents would

remain, or increase to the extent it no longer occurs in the parks.

Bridger-Teton National Forest. The USFS states that permittees on the Bridger-Teton

NF with snowmobile use have already asked about additional use days for the CDST and

other trails near Togwotee (where use is at capacity now). Requests have been received

from outfitters who currently don’t use that area but are looking for someplace to take

clients if their use in YNP is curtailed. The forest is apparently over capacity in winter

sports now in the Togwotee area, the Gros Ventre, and upper Green River. Places used

less frequently a few years ago, such as Horse Creek in the Wyoming Range and the

Greys River, are under increasing demand. Even without any management changes in

the parks, use levels that are compatible with the desired experience and setting are being

surpassed.

An overall decrease of 33.4% in nonresident use of both park and forest lands in the

GYA is expected, based on the survey of current winter visitors. In this event, there

would be no net increase in use of the forest, and quite possibly a decrease thus relieving

the current impacts stated by the USFS. The amount of use associated with local

residents would remain, or increase to the extent it no longer would occur in the parks.

Caribou-Targhee National Forests. The Targhee NF states concerns about an increase

in users and their expectation for groomed trail riding experiences. There are concerns

about possible increased demand for outfitted rides and about an increase in the

displacement of off trail users that currently access the area from the south and east. The

USFS states that users would stop in the Ashton-Island Park area to access the

backcountry rather than travel to West Yellowstone. Other increases in use could result

from people coming to the area for experiences similar to those currently available in the

park.

An overall decrease of 33.4% in nonresident use of both park and forest lands in the

GYA is expected, based on the survey of current winter visitors. In this event, there

would be no net increase in use of the forest, and quite possibly a decrease thus relieving

the current impacts stated by the USFS. The amount of use associated with local

residents would remain, or increase to the extent it no longer would occur in the parks.

 

82 The worst-case scenario indicated by the Forest Service is that the total snowmobile visitation in the three

park units would be displaced to adjacent lands on all GYA national forests. The average annual visitation is

about 84,000 snowmobile passengers through the all Yellowstone entrances and within Grand Teton. This

equates to an average daily number of snowmobile passengers over the season of about 1000 to be distributed

among the forests. Visitation data for all the forests is unavailable for comparison purposes.
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Custer National Forest. The USFS states that additional vehicles associated with

snowmobile users would likely be parked at trailhead locations and create increased

demands for parking facilities. Some additional car and truck traffic would occur along

plowed roads to trail heads. Many of these trails traverse big game winter range and

some additional vehicle-large animal collisions could occur. The period of snowmelt is

expected to increase by an additional 10 to 14 days on roads on which the snow is

compacted by snowmobiles versus areas where no snow compaction occurs. Also, the

forest is concerned that the Pryor Mountains could receive some additional use by

snowmobiles. Most use would be expected to follow existing trails or occur in existing

play areas. Displaced snowmobile activity would not be expected to go to the Ashland or

Sioux Ranger Districts.

An overall decrease of 33.4% in nonresident use of both park and forest lands in the

GYA is expected, based on the survey of current winter visitors. In this event, there

would be no net increase in use of the forest, and quite possibly a decrease thus relieving

or offsetting impacts of concern to the USFS noted above. The amount of use associated

with local residents would remain, or increase to the extent it no longer would occur in

the parks.

Gallatin National Forest. Effects of large amounts of use displaced to the forest could

be substantial: creating potential impacts to wintering big game and threatened and

endangered species; exacerbating already growing recreation health and safety issues and

trespass into closed areas; taxing existing infrastructure; and heightening recreation user

conflicts.

An overall decrease of 33.4% in nonresident use of both park and forest lands in the

GYA is expected, based on the survey of current winter visitors. In this event, there

would be no net increase in use of the forest, and quite possibly a decrease thus relieving

or offsetting impacts of concern to the USFS noted above. The amount of use associated

with local residents would remain, or increase to the extent it no longer would occur in

the parks.
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453

Shoshone National Forest. The USFS is concerned that this alternative could close

Pahaska Lodge (located outside YNP’s East Entrance) during the winters. Pahaska

Lodge now has a considerable number of year-around employees, which allows it to

maintain a stable and conscientious work force. Forcing this operation to a summer-only

operation would cause considerable disruption for the owners and employees. The

Pahaska/East Entrance is also the location of the majority of Park County’s nordic skiing

trail system. Pahaska gets the majority of its overnight use from snowmobilers, those

starting at the East Entrance or those coming from the West Entrance to stay overnight

and returning. Without snowmobiler overnight lodging or rentals, there is a high

likelihood that the Nordic opportunities in the Pahaska area would also close.

The Shoshone NF is also concerned that use on Togwotee Pass and the CDST area would

greatly increase. Increased use would exceed current infrastructure capacity (see

Bridger-Teton NF alternative G discussion) and exacerbate current identified conditions

of crowding and nonmotorized use displacement. Reconstructing or creating additional

facility capacity would be an extreme and unfinanced burden for the USFS.

A decrease of 33.4% in nonresident use of both park and forest lands in the GYA is

expected, based on the survey of current winter visitors. In this event there would be no

net increase in the use of the forest, and possibly a decrease thus relieving or offsetting

impacts of concern to the USFS. The amount of use associated with local residents

would remain, or increase to the extent that it no longer would occur in the parks. The

USFS indicates there would be a strong potential for increased snowmobile use on the

Bighorn NF.

Effects on Other Federal Lands

As described in the Chapter III, 5% of the GYA within other federal agency jurisdictions

(BLM, USFWS, and Bureau of Reclamation(BOR)). Lands under these jurisdictions

typically are not adjacent to the national parks. The potential impacts of programmatic

changes in national park management are low. Jurisdictional BOR lands associated with

Jackson Lake and Jackson Lake Dam would not be affected in any alternative more than

now. Alternatives that reduce or eliminate motorized use on Jackson Lake would be

beneficial from the standpoint of reducing any present impacts on BOR lands. The

National Elk Refuge abuts GTNP along its southeastern boundary. Because of the timing

of elk migration in the winter use season, none of the alternatives would have an adverse

impact greater than that which presently may exist. Current snowmobile use in the GYA

occurs on some BLM lands, for example, in places along the CDST. Most BLM lands lie

outside the areas that are capable of annually supporting snowmobile use because of

unsuitable snow. Changes in management represented by the range of alternatives in this

EIS would not affect marginally available snowmobiling on BLM lands. Generally, any

impacts on the national forests (should they occur) would buffer effects on other federal

lands, which do not have the capability to support great amounts of winter recreation on

snow.
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Effects on Tribal Lands and Governments

As described in the Chapter III, 4% of the GYA is within the jurisdiction of tribal or

American Indian governments. These lands are not immediately adjacent to the national

parks, and they are not legally accessible to the general public. The potential for physical

impacts on changes in national park management are low. These lands would not be

subject to any redistribution of use, nor would they appear to be indirectly affected by

possible impacts on national forests. Generally, impacts on the forests would buffer

effects, if any, on tribal lands or governments.

Direct and Indirect Effects on States and Counties

As described in the Chapter III, 3% of the GYA is state-owned lands. Some Montana

state land sections are intermingled with Gallatin NF lands north of YNP. See Effects on

the State of Montana below. Five counties are affected through gateway communities for

the three park units. In the area described as the GYA, 24% is in private ownership.

However, very little of that private land directly abuts YNP, GTNP, or the Parkway.

Private inholdings constitute less than 1% of the GTNP land base. Most of the private

lands lie within the exterior boundaries of adjacent national forests in areas that are

marginally suited for oversnow motorized use. As such, they would not directly or

indirectly be affected by any of the alternatives being considered. Through the scoping

period, and in the large volume of comments on the DEIS, no concerns or issues were

raised about possible impacts on private lands.

Effects on the State of Wyoming

There would be no impacts on state lands or private lands in Wyoming adjacent to the

parks. The NPS determined that there would be no impacts on these lands based on the

best available information about how overall use from nonresident visitors to the GYA

would either remain the same or decline through the range of alternatives. Any state or

private land near winter uses would have similar or less pressure. No such effects were

identified by the State of Wyoming.

Alternative A

The State of Wyoming identified no impacts associated with alternative A. The NPS

notes that a number of statements made regarding air, water, and wildlife apply to the

existing condition, not to what may happen as a result of other alternatives.

Alternative B

Water Quality. The State notes that any alternative involving an increase in road use

and maintenance in the parks could affect surface waters during spring runoff. The State

further notes that the parks should consider impacts to surface waters due to plowing,

sanding, or improper snow removal, and that snow storage sites should be carefully sited

so that seepage and runoff do not go directly into surface or ground water. Storage areas

should be engineered to capture pollutants in melt water. These observations apply

basically to water quality within the parks, which is evaluated in the water quality section

for each alternative. The State does not express concern about impacts on waters of the
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455

State outside the parks. Given the State’s concern regarding the content of plowed,

stored snow, and its potential to affect runoff, there is equal concern regarding pollutants

from oversnow vehicles in the stored, compacted snow on groomed surfaces. Miles of

groomed surfaces are immediately adjacent to surface waters, as reflected in the risk

analysis for each alternative under water resources.

Air Quality. The State notes that the proposed snowmobile emission threshold may not

be achievable. If it is not, the State also says, the result could be the total elimination of

snowmobiles from the parks, as we know them today by 2008-2009. The NPS asserts

that this is not a statement of effects on air quality, but rather on the willingness of

industry and State to acknowledge there is a problem. The State expresses no concern

about air quality impacts in the park because there are no documented violations of State

pollution standards. The Park Service’s assessment is that the intent of this alternative to

improve air quality in the parks would improve air quality in the State.

Wildlife. The State does not expect a “significant” effect on wildlife management east of

YNP since population sizes of bison and elk within the park are more of a factor than is

accounted for by winter use planning. Both motorized and nonmotorized winter

recreation are of concern in the Jackson area. Impacts within GTNP are discussed in the

wildlife section for each alternative. The State suggests additional closures be applied.

The State also notes that elimination of snowmobiles on Jackson Lake would unjustly

limit recreational fishing on the lake. The NPS notes that this action would also

eliminate a source of pollution that would go directly into surface water, and that access

for fishermen would still be allowed by other means.

Recreation. In its written comments, the State of Wyoming provided an assessment of

impacts on snowmobile recreation in the park. The NPS, as the manager for this use in

national parks, has performed this assessment and disclosed the consequences under

Visitor Access and Experience for alternative B, in Chapter IV. No impacts have been

identified for State lands in Wyoming, or private lands in Wyoming adjacent to the parks.

Economics. Economic impacts on the State of Wyoming are considered and disclosed in

Economic Effects, Chapter IV.

Alternative C

Water Quality. Potential impacts expressed by the State are the same as in alternative

B.

Air Quality. No impacts were identified by the State, other than a positive effect with

the proposed reduction in snowmobile emissions. The NPS assumes that this statement is

based on the requirement for the use of bio-based fuels. However, in many respects,

alternative C is similar to alternative B, so impacts noted for that alternative by the State

also apply to this alternative.
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456

Wildlife. The State does not expect a “significant” effect on wildlife management to the

east of YNP since population sizes of bison and elk within the park are more of a factor

than is accounted for by winter use planning. The State notes that both motorized and

nonmotorized winter recreation are of concern in the Jackson area. Impacts within

GTNP are discussed in the Wildlife section for each alternative. The State suggests

additional closures be applied to areas where nonmotorized activities occur.

Recreation. The State notes that plowing the road from West Yellowstone to Old

Faithful will cause a loss of opportunity for overnight stays in West Yellowstone by

individual and commercial users from the South, North, and East Entrances. A number

of other impacts within the park are disclosed in the Visitor Access and Experience

section for alternative C. No impacts have been identified for State lands in Wyoming,

or private lands in Wyoming adjacent to the parks.

Economics. Economic impacts on the State of Wyoming are considered and disclosed in

the Economic Effects section of the EIS.

Alternative D

Water Quality. Potential impacts expressed by the State are the same as in alternative

B.

Air Quality. Potential impacts expressed by the State are the same as in alternative B.

Wildlife. Potential impacts expressed by the State are the same as in alternative B.

Recreation. The State notes that closure of the East Entrance of YNP would adversely

affect motorized recreation opportunities in northwest Wyoming as most of other lands

within the snowbelt are designated wilderness and therefore off-limits. NPS use figures

indicate that this would affect an average of 36 snowmobiler days, and peak day usage of

64. Not only are many areas unavailable on the Shoshone NF because they are in

wilderness, they are also unavailable due to lack of reliable snow and prohibitive terrain.

The Custer NF to the north is largely unused by snowmobiles for the same reasons.

Other impacts noted by the State are disclosed in Visitor Access and Experience sections

for alternative D, Chapter IV.

Economics. The State notes that Flagg Ranch would experience a significant negative

impact. It also notes that the impact could be minimized or eliminated if the parks and

the ranch could work together to convert Flagg Ranch to a destination site. With the

Grassy Lake route, this could provide an improved interior experience for snowmobile

users and facilitate a potential net gain in revenues. This is the expressed rationale of

NPS in proposing such an alternative feature, along with other positive aspects. The NPS

agrees that, like the current experience offered at Old Faithful, there is a special

experience involved in access to destinations via oversnow means. Other economic

impacts on the State of Wyoming are considered and disclosed in Economic Effects,

Chapter IV.
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457

Alternative E

Water Quality. Potential impacts expressed by the State are the same as in alternative

B.

Air Quality. The State notes the likelihood of positive effects on air quality issues

through establishment of an advisory committee. The NPS notes that this is a tacit

agreement that air quality issues exist, but that they would not be addressed directly. The

establishment of such a committee would not directly improve air quality.

Wildlife. Potential impacts expressed by the State are the same as in alternative B.

Recreation. The State notes that closure of the CDST would adversely affect motorized

recreation opportunities in the western United States as the vast majority of other lands

within the snowbelt is designated as wilderness and therefore off limits. The NPS

disagrees with this assessment, as shown elsewhere in this document. The CDST in

GTNP is used only marginally, and that is primarily for access into YNP. This

opportunity remains, and a shuttle service would be provided to transport CDST users

from the GTNP’s east boundary to Flagg Ranch. The NPS agrees that the experience

would be changed, but the opportunity remains. Other impacts noted by the State are

disclosed in Visitor Access and Experience for alternative D, Chapter IV.

Economics. Economic impacts on the State of Wyoming are considered and disclosed in

Economic Effects, Chapter IV.

Alternative F

Water Quality. Potential impacts expressed by the State are the same as in alternative

B.

Air Quality. The State notes that there would be a positive effect on air quality by

adopting new technology as it becomes available.

Wildlife. Potential impacts expressed by the State are the same as in alternative B.

Recreation. Many of the State’s observations about recreation impacts are disclosed in

Visitor Access and Experience for alternative F, Chapter IV. Other comments by the

State follow. Closing the road from West Yellowstone to Old Faithful, Norris to

Mammoth, and from Madison to Norris would cause a loss of capacity for overnight

stays in West Yellowstone and at Mammoth by individual and commercial users from the

South and East Entrances. Eliminating the CDST and Grassy Lake Road would

adversely affect motorized recreation opportunity in Wyoming and GTNP, as well as in

the western United States. These trails help link independent trail systems to create a

unique snowmobile recreation opportunity unequaled west of the Mississippi River. This

closure would destroy the connecting link to snowmobile trail systems in the states of

Idaho and Montana. See previous alternative: alternatives E and F are the same for

GTNP.
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Economics. Economic impacts on the State of Wyoming are considered and disclosed in

the Economic Effects section of the EIS.

Alternative G

Water Quality. Potential impacts expressed by the State are the same as in alternative

B. The Park Service’s assessment is that the risk of impacts to water quality would be

decreased by eliminating a major source of pollution in the parks’ snowpacks. See

impacts in the Water Resources section for this alternative, Chapter IV.

Air Quality. The State notes that there would be a positive effect on air quality by

allowing mass transit oversnow vehicles only.

Wildlife. Potential impacts expressed by the State are the same as in alternative B.

Because of concerns expressed by the State, as discussed in Chapter III, recommended

mitigation has been added into alternative F.

Recreation. The State notes that eliminating the snowmobile experience in the parks

will greatly reduce recreation visitation. Also that eliminating the CDST would

adversely affect motorized recreation opportunity in Wyoming and GTNP, as well as in

the western United States. The results of the winter use survey indicate that nonresident

winter visitation to the GYA would decrease by 33.4% in this alternative. Much of this

visitation loss would be attributed to snowmobilers who would go elsewhere. The Park

Service’s assessment is that there would most likely be replacement visitation from a

national market of people who would come to the GYA and recreate, partly owing to the

new opportunities and experiences offered in the parks in this alternative.

Economics. Economic impacts on the State of Wyoming are considered and disclosed in

Economic Effects, Chapter IV.

Effects on the State Of Montana

Alternative A

The State of Montana identified no impacts associated with alternative A. However, the

State expresses concerns about effects for all alternatives as follows: “Montana

Department of Fish, Wildlife and Parks owns important wildlife habitat in the heart of the

Gallatin Canyon. These lands lie in a checkerboard arrangement with the Gallatin

National Forest. Any of the alternatives that propose closing access to the park from

West Yellowstone could lead to impacts on important and sensitive wildlife winter

ranges in the Gallatin Canyon. These lands provide important winter habitat for elk,

moose, and bison. These lands are primarily situated from the Gallatin Canyon park

entrance north to the Porcupine drainage and also includes land in the Taylor Fork.

Montana Department of Fish, Wildlife and Park’s effectiveness in managing winter

recreation is directly influenced by Gallatin National Forest management due to the

checkerboard pattern.” The NPS assumes that the State means closing access to

snowmobiles, because access is provided from West Yellowstone in all alternatives but
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459

alternative F. No impacts have been identified specifically for State lands or private

lands in Idaho adjacent to the parks.

The NPS determines that there would be no significant impacts on other State or private

lands. This is based on the best available information from the winter use survey about

how overall use from nonresident visitors to the GYA would either remain the same or

would decline through the range of alternatives. Any State or private land near winter

uses would have the same or less pressure.

Alternative B

The State notes that under alternative B plowing the road from West Yellowstone to Old

Faithful would be disruptive to West Yellowstone's local economy and established visitor

service system. Based on field experience and trails program administration, the State

foresees a scenario where the level of visitation in the West Yellowstone area by the

snowmobiling public will remain level or increase regardless of whether alternative B is

implemented. According to the State, several areas exist in which significant negative

impacts are expected to occur outside the park as a result of implementing alternative B.83

Wildlife. The State notes that snowmobilers would likely be diverted to national forest

lands surrounding the YNP and West Yellowstone. The State is concerned that elk

winter range in the Hebgen and Taylor Fork areas, which have seen little or no use,

would be significantly impacted if large numbers of snowmobilers were diverted away

from the park and onto the adjacent national forest lands. These winter ranges are

important to maintaining Montana's elk populations, and are more sensitive compared to

the groomed road from West Yellowstone to Old Faithful. The Park Service’s estimate

of displaced use is given at the beginning of this section.

In this context the best information available indicates that use in the GYA would decline

by 18.4% thus relieving pressures on adjacent lands. If this scenario occurs, there could

be an economic impact as the State suggests (assuming no replacement visitation).

However, if snowmobilers stay in West Yellowstone and use adjacent lands creating an

inordinate impact on wildlife, then there would be no economic effect. The two

hypotheses are not consistent.

The State indicates that the area north of Hebgen Lake, known as the "Hebgen Face" near

Kirkwood and Red Canyon, is designated winter range and has a resident elk population

through the winter. In the past this area has experienced little conflict between wildlife

and snowmobilers. The concerns expressed above may exacerbate impacts to elk on this

winter range. Also the State feels that a potential result would be a flood of snowmobile

travel north through Cabin Creek to Carrot Basin and into the Taylor Fork drainage.

Several outfitted and private snowmobile groups may try to travel through the Taylor

Fork winter range to connect with the Buck Ridge area and then on into Big Sky. Last,

 

83 All the following listed impacts are expressed by the State of Montana using an assumption of total

displaced use from the parks to adjacent lands. See the use displacement scenarios at the beginning of this

section.
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according to the State, any substantial increases in the number of snowmobilers trying to

reach Big Sky from Wapiti Y, (Taylor Fork drainage) by any number of routes, may

significantly impact bear denning sites. Cache Creek, Beaver Creek, and the Yellow

Mules have known grizzly bear denning sites.

The State notes that during this period, use of the roads by bison increases, and bison

more readily move longer distances and could exit the park more easily than on groomed

snowmobile trails. They believe there would be a tunnel effect created by winter

plowing, encouraging bison movement out of the park and complicating bison

management in West Yellowstone and Horse Butte. The State recommends including

mitigation provisions for the plowing option, such as clearing exit lanes at key trail break

off points for bison and elk, or modifying snow removal methods to eliminate an

accumulation of snow along side the road system. The Park Service’s analysis (See the

analysis of impacts on bison and ungulates for alternative B) indicates that bison make

little use of groomed surfaces by bison to exit the park, and such mitigation is already

included.

The State is concerned about the potential for any substantial and unexpected increase in

snowmobile use north of the park boundary. Travel management concerns in the Gallatin

Canyon would become a major focus for the State and the Gallatin NF. The State says

that riding from West Yellowstone to the Taylor Fork drainage, many snowmobilers

want to continue their travel onto Big Sky. Also snowmobilers choose to travel out of

the Taylor Fork drainage using the plowed access road to Highway 191. The use of the

maintained road is illegal under Montana statute. Using the barrow pit along Highway

191, snowmobilers travel north, and at times travel on the pavement of the highway, to

Buck Ridge trailhead. From this point they can easily access the Big Sky area for

services such as gas, food, and lodging. Snowmobiles also travel the return route,

resulting in several recent near-miss accidents. As regrettable as these circumstances are,

they appear to be outside the jurisdiction of the park, and would continue apart from any

future management change (alternative) that the park may implement.

Alternative C

The State offers the same comments as in B regarding the plowed section of road.

Alternatives D and E

The State offers no impact analysis for these two alternatives.

Alternative F

The State reiterates comments from alternative B regarding their suggestions to mitigate

air quality impacts at the West Entrance. See also the discussion under alternative A.

Alternative G

The State notes that this alternative would place additional stress on “some of the most

sensitive natural resource areas north of the park,” which currently receive high and

increasing amounts winter snowmobile recreation activities. The NPS notes that there
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461

are no specific statements of impact supporting this conclusion. Assuming the State is

referring to lands on the Gallatin NF, the reader is referred to the earlier section regarding

impacts on national forest lands. Regarding State lands, refer back to Effects on the State

of Montana in this section.

Effects on the State of Idaho

No impacts have been identified specifically for State lands or private lands in Idaho

adjacent to the parks. The NPS determines that there would be no significant impacts on

these lands, based on the best available information about how overall use from

nonresident visitors to the GYA would either remain the same or decline through the

range of alternatives. Any State or private land that lie in close proximity of winter uses

would similarly have the same or less pressure.

Alternative A

The State presents no impacts associated with current management.

Alternatives B through G

The State notes it is likely that a plowed road in alternatives B and C from West

Yellowstone to Old Faithful will result in additional pressure on snowmobile trail

opportunities in Idaho. Presently the Fremont County snowmobile trail system only has

three snowmobile trail groomers to maintain 400 miles of trail. An additional influx of

snowmobiles from West Yellowstone would place more wear on existing Fremont

County snowmobile trails. The State says that some of these trails are already at their

maximum level of use, and are groomed once weekly.

The State indicates that alternative G would displace 100% of the snowmobile visitors to

the parks who would either recreate on adjacent lands or not come to the GYA. The

State says that eliminating access to Flagg Ranch would disconnect visitors from the

CDST in Wyoming and 20 miles of trail that represent a unique experience. Also they

indicate that this lack of access eliminates groomed snowmobile access to Cave Falls,

and that snowmobilers would still use this route, which is within two miles of the park

boundary. The State’s opinion is that alternative G has irreversible and irretrievable

consequences, including loss of personal freedom for winter visitors, loss of opportunity

for visitors who cannot ski or snowshoe, loss of opportunity to view YNP by

snowmobile, and loss of Idaho’s version of the Grand Loop experience. In addition the

State feels that the elimination of snowmobiling would cause increased safety problems

outside the parks from congestion and trail deterioration.

In this context the best information available indicates that use in the GYA would decline

by 18.4% in alternative B and 33.4% in alternative G, thus relieving pressures on

adjacent lands. If either scenario occurs, there could be an economic impact as the State

suggests (assuming no replacement visitation). However, if snowmobilers stay in West

Yellowstone or in Idaho and use adjacent lands, creating additional safety problems as

stated, then there would be no economic effect. The two hypotheses are not consistent.
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Effects on Teton County, Wyoming

The NPS determined that there would be no significant impacts on lands within the

jurisdiction of Teton County. This is based on the best available information from the

winter use survey about how overall use from nonresident visitors to the GYA would

either remain the same or would decline through the range of alternatives. Any state or

private land near winter uses would have the same or less pressure.

Alternative A

According to the County, there would be no significant recreation or economic impacts.

Alternative B

The County states that there is the potential for a significant increase in visitation to YNP

through the South Entrance as a result of eliminating oversnow access from West

Yellowstone. Their opinion is that this could result in an increase of rental sleds both in

Jackson as well as at Flagg Ranch. The County also thinks it likely that the amount of

commercial guiding originating in Teton County would increase. The County did not

estimate the dollar amount of impact, not knowing potential visitation numbers,

infrastructure constraints, or commercial permit restrictions.

The County’s opinion is that eliminating snowmachines on the Teton Park inside road

should not have a significant economic impact to Teton County because the area is

mostly used locally, and states it could have an economic benefit to Teton County by

drawing more skiers to the area.

Teton County believes that relocating the CDST to a year-round pathway should provide

economic benefits to Teton County by drawing more users to the area. In addition it

recommends opening the trail to commercial use to provide additional economic benefit

to the county.

Alternative C

The County states that relocating the CDST to a utility corridor from Moran to Flagg

should greatly improve both the safety of the trail as well as recreational experience for

snowmobilers in GTNP. Further, if the trail were open to commercial users it could draw

significantly more users and benefit the county economically.

The County indicates the potential for a significant increase in visitation to YNP through

the South Entrance as a result of eliminating oversnow access from West Yellowstone.

The County states that this would result in an increase of rental sleds both in Jackson as

well as at Flagg Ranch, and an increase in the amount of commercial guiding originating

in Teton County.

Alternative D

The county states that relocating the CDST to the utility corridor from Moran to Flagg

would greatly improve trail safety and recreational experience for snowmobilers in

GTNP. It recommends opening the trail to commercial use to provide additional

economic benefit to Teton County.
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The County believes that closing the road north of Colter Bay to wheeled-vehicles and

opening it to snowmobiles could have adverse and beneficial impacts. By eliminating the

ability to stage commercial and individual snowmobile trips from Flagg Ranch, the trip to

Old Faithful may be too long for most users for a day trip. This could significantly

reduce both the number and ability of visitors from Teton County to experience YNP via

snowmobile in one day. Conversely, according to the County, closing this section of

road would provide an improved snowmobile experience in GTNP. They state that if

commercial guides were permitted to stage trips out of Colter Bay, use within GTNP

could rise dramatically.

The county’s opinion is that eliminating snowmobiles on the Teton Park Road should not

have a significant economic impact to Teton County because the area is mostly used

locally. The County states it could have an economic benefit to Teton County by

drawing more skiers to the area.

Teton County states that relocating the CDST to a utility corridor would provide

economic benefits to Teton County by drawing more users to the area, and that opening

the trail to commercial use would provide additional economic benefit to the county.

The County states that closing the road north of Colter Bay to motor vehicles could have

significant negative economic impacts to Teton County. It indicates that Flagg Ranch

currently rents over 5,000 snowmobiles per year to visitors who enter YNP. If the road

were closed, visitors would either need to rent their sleds at Colter Bay or be shuttled to

Flagg Ranch via snowcoach. In addition 12 concessioners offer guided snowmobile

tours into YNP via the South Entrance. According to the county, the trip to Old Faithful

may be too long to stage from Colter Bay and could result in a loss of about $671,000.

The county suggests that if the concessioners were allowed to stage out of Colter Bay,

visitors could experience GTNP and perhaps YNP, and concessioners would recoup most

of those costs.

Alternative E

The County’s opinion is that eliminating snowmachines on the Teton Park inside road

would not have a significant economic impact to Teton County because the area is mostly

used locally. The County states it could have an economic benefit to Teton County by

drawing more skiers to the area.

The County’s opinion is that eliminating all motorized vehicles on Jackson Lake and

closing the CDST could cause impacts to Teton County. They State that without the

trail, the only local opportunity to snowmobile in a national park would be a trip into

YNP.
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Alternative F

The County’s observations on recreation impacts are the same as in alternative C.

The County states that eliminating access from West Yellowstone and Mammoth could

results in a significant increase in visitation to YNP through the South Entrance. Further,

it believes this could result in an increase of rental sleds both in Jackson as well as at

Flagg Ranch, and that commercial guiding originating in Teton County likely would

increase.

Alternative G

The County’s opinion is that eliminating snowmachines on the Teton Park inside road

would not have a significant economic impact to Teton County because the area is mostly

used locally. The County states it could have an economic benefit to Teton County by

drawing more skiers to the area.

The County’s opinion is that eliminating all motorized vehicles on Jackson Lake and

closing the CDST could cause impacts to Teton County. They State that without the

trail, the only local opportunity to snowmobile in a National Park would be a trip into

YNP.

The County suggests that this alternative lacks opportunities for groomed trail nordic

skiing. The County states that there is a lack of public recreation opportunities and that

the NPS is ignoring this need.

Closing the road north of Colter Bay to wheeled-vehicles and opening it to mass transit

oversnow vehicles could have both significant adverse as well as beneficial impacts,

according to the county. It states that by eliminating the ability to stage commercial and

individual snowmachine trips from Flagg Ranch, this would eliminate the ability of

visitors from Teton County to experience YNP via snowmobile. Current commercial

outfitters as well as Flagg Ranch would be impacted significantly. The county also

believes that, conversely, providing oversnow mass transit may draw new visitors to

Teton County that prefer this type of recreation and atmosphere and create economic

benefit.

Effects on Gallatin County, Montana

Gallatin County indicated that its survey of businesses in the County would be used to

determine overall economic impacts. The County offers no specific assessments of

impacts for each alternative. Economic impacts on the County are considered and

addressed in the socioeconomic effects section of this document. The NPS determines

that there would be no significant impacts on lands within county jurisdiction, based on

the best available information about how overall use from nonresident visitors to the

GYA would either remain the same or decline through the range of alternatives. Any

State or private land near winter uses would have the same or less pressure.
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465

Effects on Park County, Montana

Input from this cooperating agency does not provide an assessment, by alternative, of

socioeconomic impacts. It notes that alternative B would have a devastating effect on the

economy of West Yellowstone, which is not located in Park County. Park County

indicates that it does not have a booming economy and that wages and employment have

declined. The results of a survey conducted with businesses in Park County have been

reviewed. Related economic impacts are considered and addressed in the socioeconomic

effects section of this document. From the results supplied with Park County’s

comments on the DEIS, it would appear that important conclusions are difficult to

ascertain. The survey is predicated on either the closure of the park (which is not an

alternative) or closure to snowmobiles (alternative G). The listing of results does not

allow determination of whether the winter visitors in question are snowmobilers or

people who ski or travel by snowcoach. For example, the results list lost sales if YNP

“winter visitors” were prohibited – this presumes closure of the park. Also it is difficult

to determine, from the questions asked about winter business closures, which of the

businesses would close during the winter whether or not park management could change.

The NPS determined that there would be no significant impacts on lands within county

jurisdiction, based on the best available information about how overall use from

nonresident visitors to the GYA would either remain the same or decline through the

range of alternatives. Any state or private land near winter uses would have the same or

less pressure.

Effects on Fremont County, Idaho

Information provided by this cooperating agency includes a report on the economic

importance of the winter season to the County. It states that the county provides a variety

of winter recreation opportunities, and that it provides a connector for important winter

destination areas including the parks, West Yellowstone, and Flagg Ranch. The

County’s winter population increases due to annual snowmobiler days of 300,000, and

40,000 days attributed to other recreation users. As background, the county notes that

pressure on the local trail system (400 miles of groomed trail) and related facilities

increases when YNP closes for the season. It experiences 1,200 more snowmobilers per

weekend following the closure. Specific to alternative G, which closes the Grassy Lake

Road to snowmobile use, the county believes that without groomer access to fuel at Flagg

Ranch, it would be unable to groom two high-use trails of about 67 miles. Similarly,

snowmobiles would not have access to fuel in trail experiences. The County also states

that some opportunities near, or perhaps on, the park from the Idaho side would continue

to be used by snowmobilers, and this would necessitate additional enforcement effort by

the NPS.

Leaving the Grassy Lake Road open for snowcoach use mitigates the county’s concerns

to some degree. The need for grooming the road surface remains. This would facilitate

the grooming of trails on adjacent lands.
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The NPS determined that there would be no significant impacts on lands within county

jurisdiction, based on the best available information about how overall use from

nonresident visitors to the GYA would either remain the same or would decline through

the range of alternatives. Any state or private land near winter uses would have the same

or less pressure.

Effects on Park County, Wyoming

This cooperating agency did not identify specific impacts, by alternative, on the County

or private lands within it. The NPS determined that there would be no significant

impacts on lands within the County jurisdiction, based on the best available information

about how overall use from nonresident visitors to the GYA would either remain the

same or decline through the range of alternatives. Any state or private land near winter

uses would have the same or less pressure.

Cumulative Effects on Adjacent Lands

Effects analysis on adjacent lands, as constituted in this EIS, is inherently a cumulative

impacts analysis. Cumulative impacts are defined as the effects of the proposed action,

added to the past, present, and reasonably foreseeable impacts in the area of concern.

The determination of cumulative impacts is required in an EIS, but the potential for

cumulative impacts is not a CEQ regulated constraint on the eventual decision. In other

words, impacts may be incurred by virtue of a decision as long as they are not in

violation of a law, and if they are disclosed properly, considered, and mitigated (if

possible).

Framework for Analysis

This analysis is conducted by identifying the area of concern for a resource, determining

all impact sources on the resource within the area, and then assessing the additive impact

of the proposed action on that resource and the total cumulative impact. The frame of

reference for this analysis is as follows:

1. Since the major source of impact would be potential displacement of snowmobile use from

national parks to national forests in the GYA, the context for the issue is how use might

change in the GYA. The primary change would be in relation to numbers of visitors from

outside the GYA, and how they would react to alternatives that affect snowmobile access

to the parks. Use and access by residents could be locally redistributed; as it may affect

total use in the GYA, it could only decrease as a result of the alternative changes. The NPS

assumes it would remain within the GYA; that is, local users would continue to use the

GYA as at present. They could go to other GYA areas, described as “local redistribution”

in this analysis.

2. Existing forms of recreation access and opportunity in the parks could directly affect

alternatives and alternative features.

3. Some of the people who may be affected by alternatives or alternative features might be

displaced to adjacent lands. These are indirect or secondary effects, which are removed in

time or space from the source of impact.

4. Some of the use that is displaced to adjacent lands could cause further impacts on those

lands or their resources. These are secondary or tertiary effects, which are removed in time

or space.
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467

5. The additional use on adjacent lands is added to the existing use on those lands, concurrent

with increasing use from other sources. This is the total cumulative impact.

Areas and Resources of Concern

In this analysis the State of Montana and the national forests have expressed concerns

about potential impacts of various alternatives on resources in those jurisdictions.

Wyoming and Idaho have not directly expressed such concerns, although both allude to

changes in recreation within those states. The resources of concern include recreational

opportunity and experience (including associated facilities: trails and trailheads); and

wildlife (including threatened and endangered species). The area of concern is that

which is subject to potential displaced snowmobile use; this is the entire GYA area

outside the parks that is capable, suitable, and available each year to support seasonal

snowmobile use. This area is defined and mapped in the GYCC Multi-Agency Winter

Visitor Use Assessment (1999).

Source of Impact from the Proposed Action

The source of impact for all concerns expressed by cooperating agencies is the

displacement of winter recreation use, primarily snowmobiles, associated with

identifiable features in the range of alternatives. These are: plowing the road from West

Yellowstone to Old Faithful (alternatives B and C); closing the North and West

Entrances (alternative F); closing the East Entrance (alternative D); removing the CDST

(alternatives E and F); and closing all park units to snowmobiles (alternative G). The

USFS expressed concern about backcountry closures in YNP in alternative F, and

removing skiing opportunities from Colter Bay to Flagg Ranch (alternatives D and G).

Alternative-specific scenarios of displacement were developed and supplied to the USFS

at its request. The NPS used information available in the DEIS and the winter visitor

survey to assess generally how many people (in different user groups) would continue to

visit the GYA relative to various park management changes.

The scenarios used by NPS are displayed at the beginning of the section entitled Direct,

Indirect, and Cumulative Effects on Adjacent Lands and in Appendix G. They are

dependent on the winter visitor survey results developed by Duffield and Neher (2000a)

for this EIS. In short, use of the best available information about what current winter

visitors would do shows that overall visitation in the GYA by nonresidents (80% of the

visitation) could decrease substantially in alternatives B, C, F, and G. Visitation would

remain the same in A and E, but decline slightly in D. Visitation to the GYA affects both

national parks and national forests.

Past, Present, and Reasonably Foreseeable Impact Sources in the Areas of

Concern

Montana, Idaho (Fremont County), and the USFS all were concerned about use

(primarily snowmobiles) being displaced from the park units and added to the use that
CHAPTER IV

ENVIRONMENTAL CONSEQUENCES

468

already exists in their jurisdictions.84 General statements are provided by those

cooperating agencies about current use at a threshold, crowding and demand on facilities

and popular areas, safety, displacement of nonmotorized users, and important winter

habitat for a variety of ungulate species. Other issues relating to the indirect, secondary,

and tertiary effects of use displaced from the parks includes denning grizzly bears, spring

bear emergence, nesting bald eagles, and lynx habitat.

All such concerns for national forests were expressed as conflicts and mapped in the

multi-agency assessment for winter visitor use in the GYA. A summary of these

concerns is found under alternative A in the section entitled Direct, Indirect, and

Cumulative Effects on Adjacant Lands and in Appendix G. A statement of concern from

Montana may be found under alternative A in the section on Montana. Effects on

Fremont County, Idaho, above, speak to current pressures on its trail system. For

cumulative effects analysis, regarding these adjacent lands, it appears that either the

current level of impact is high or concern exists about greater use in areas of currently

low density use. All these entities also state that the foreseeable impacts due to winter

use on their lands will increase, because of the present rate of growth in the sport. The

Targhee NF notes an annual 4% to 5% increase. Therefore, the environmental baseline

for assessing cumulative impacts on adjacent lands must account for: current high level

of impacts and conflicts in some areas, with increasing trends in use.

Total Cumulative Impact

Management changes in the three park units could result in local redistribution of use

which, added to current use and demand, could cumulatively impact resources or values

on adjacent lands (given the characterizations of current condition by the USFS,

Montana, and Fremont County, Idaho). These impacts might include: further stress on

facilities and infrastructure, habitats, and deteriorating recreation experiences and

opportunities in some areas outside the parks.

• For the USFS, identified areas of high use conflict85 would presumably increase in

magnitude, extent, and duration (Island Park, Gallatin Canyon, Togwotee Pass, Beartooth

Plateau, Cooke City, et al.). Conflict areas identified as being low or moderate in intensity

could become worse. Additional areas not previously identified as being of concern could

arise.

• For Montana, winter ungulate habitat in Gallatin Canyon could be further impacted, with

resultant stress on individual animals and overall negative impacts on populations.

• For Idaho, the Fremont County trail system would experience further demand and

crowding resulting in a decline in visitor experience and increased grooming expense.

• In all areas motorized use would tend to affect desired experiences of nonmotorized users

and displace that use from ever-decreasing areas of opportunity.

 

84 In contrast, the State of Wyoming expressed no such concerns. Its overriding assumption in all economic

and recreation analyses is that the snowmobiles will no longer come to the GYA in most management change

scenarios.

85 See assessment of alternative A for Effects on National Forest Lands, and the Winter Visitor Use

Management Assessment as cited therein.
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469

The NPS assessment of total cumulative impact on adjacent lands in the GYA includes

the following considerations.

• The major source of impact is potential displacement of snowmobile use from national

parks to national forests in the GYA. The context for this issue is how use might change

overall in the GYA. The primary change would be in relation to visitors from outside the

GYA and how they would react to alternatives that affect snowmobile access to the parks.

As documented throughout this section. This visitation would be expected to decline

substantially in alternatives B, C, F, and G. It would remain the same or decline slightly in

A, D, and E.

• Use and access by residents could be locally redistributed, but it is generally accounted for

within the current condition. The NPS assumes it would remain within the GYA; that is,

local users would continue to use the GYA in the same amount as at present but they could

go to other areas (described as “local redistribution” in this analysis). Local redistribution

scenarios are hypothesized at the beginning of the Direct, Indirect, and Cumulative Effects

on Adjacent Lands section.86 In alternatives B, C, F, and G, the total decline in visitation to

the GYA would more than offset any local redistribution increases – unless resident use

comprises most of the current total use.

• The USFS in its assessment of winter use identified management actions that could be

taken to relieve conflict areas on national forest lands. Some forests identified unused or

minimally used lands, which could be made more accessible by developing parking or

trailhead facilities. There may be unused capacity on forests to absorb local redistribution.

• In the context of cumulative effects, the proposed action may not be, and arguably should

not be, the only focus of mitigation or change in management. National forests are

governed by forest plans and other constraining rules, regulations and agreements that

prescribe or specify management actions in relation to resource conditions or, for example,

habitat needs. The USFS indicates that not all plans directly or consistently address species

requirements or changed conditions (winter use, newly listed species). However, plans,

strategies, and guidelines must be followed for lynx, bears, wolves, eagles, or other

currently listed species for each forest.

• NEPA (CEQ Regulations) does not require that an EIS discuss remote and conjectural

consequences, and that decisions need not be made on the basis of possible, but

speculative, effects.87

• An EIS is adequate if it provides discussion of direct and secondary impacts and conflicting

scientific judgments regarding cumulative effects.88

Alternative A

Cumulative impacts have been ascertained, considering existing and reasonably

foreseeable direct and indirect effects on adjacent lands to the degree necessary.

Environmental effects that are easily identified are disclosed in detail, and effects that

cannot readily be ascertained are nonetheless discussed sufficiently.89 This alternative

would not displace additional use from the parks to adjacent lands, while impacts of

current use would continue on adjacent lands at the present level.

 

86 Forest Service views a worst-case scenario to be appropriate, where worst-case represents displacement of

all current users in the parks to adjacent lands. For reasons presented at the beginning of the adjacent lands

section, NPS believes the best available information is presented through the survey of current visitors and

that a worst-case scenario remains subject to too many assumptions. FS’ worst-case is refuted by the visitor

survey.

87 Sierra Club v. Hodel, 544 F.2d 1036, 1039 (9th Cir. 1976), et al.

88 Environmental Defense Fund, Inc. v. Hoffman, 566 F.2d 1060 (8th Cir. 1977), et al.

89 Citizens for Environmental Quality v. U.S., 731 F.Supp. 970, 995 (D. Colo 1989) held that for effects not

readily ascertained, detailed discussion is not contemplated under NEPA.
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Alternative B

By virtue of the closure of YNP’s West Entrance to snowmobiles, local use could be

redistributed to adjacent lands, along with a percentage of nonresident visitors who state

they would return to the GYA in the circumstances posed by alternative B. The NPS

estimates this amount to be about 6,700 snowmobiler trips over the season, or 75

snowmobile trips daily. The overall cumulative impact would be a decrease in use on

adjacent lands because of an 18.4% reduction in nonresident visitation to the GYA. The

75 trip redistribution per day, divided between adjacent lands on the west side of YNP

(where 300,000 snowmobiler days are currently experienced) would be negligible. Users

displaced from the Teton Park Road and the surface of Jackson Lake average 45 to 50

snowmobiler trips per day, who would either enter YNP or go elsewhere on the Targhee,

Shoshone, or Bridger-Teton National Forests. Some displaced users would enter the

parks at other gateways and not impact adjacent lands. The level of congestion and

conflicts currently identified on the west side of YNP could improve due to lower use by

nonresident snowmobilers.

Alternative C

Total cumulative impact would be the same as that described in alternative B. The late

season plowing of the Mammoth to Madison road segment could further displace local

use by 1,700 visitor trips during February and March to adjacent lands near Gardiner and

Cooke City. Again, this could be offset by a total nonresident reduction in use in the

GYA of 18.4% in terms of total cumulative impact.

Alternative D

By virtue of closing YNP’s East Entrance to snowmobiles, use that could be displaced to

elsewhere in the GYA amounts to about 3,300 snowmobiler visits over the season, or an

average of 40 snowmobiler trips per day that could go to other gateways or to national

forest lands. Users displaced from the Teton Park Road and the surface of Jackson Lake,

which amounts to an average of 45 to 50 snowmobile trips per day combined, would

either enter YNP or go elsewhere on the Targhee, southern Shoshone, or Bridger Teton

National Forests. By virtue of a 4.4% reduction in total visitation by non-GYA residents,

the total cumulative impact on adjacent lands would decline slightly. Due to local

redistribution and uncertainty in use numbers, the overall cumulative impact in the GYA

would be indistinguishable from the current condition.

Alternative E

This alternative would not reduce visitation by nonresidents. Local use in GTNP would

be displaced by the closure of the Teton Park Road and the CDST segment within the

park. Use on the CDST is almost exclusively destined for YNP, most of it being staged

from Flagg Ranch. In alternative E, this opportunity remains available, so this amount of

use would likely not be displaced to adjacent lands. Users displaced from the Teton Park

Road and the surface of Jackson Lake, which amounts to an average of 45 to 50

snowmobile trips per day combined, would either enter YNP or go elsewhere on the

Targhee, southern Shoshone or Bridger-Teton National Forests. As a percent of use on
DIRECT, INDIRECT, AND CUMULATIVE EFFECTS ON ADJACENT LANDS

471

the latter two forests, this would not appear to be significant. The overall cumulative

impact in the GYA would be indistinguishable from the current condition.

Alternative F

By virtue of closing YNP’s West and North Entrances, local use could be redistributed to

adjacent lands, along with a percentage of nonresident visitors who state they would

return to the GYA in this use scenario. The NPS estimates this amount to be about 4,000

snowmobiler trips over the season; or 50 snowmobile trips daily. The overall cumulative

impact would be a decrease in use on adjacent lands because of a 24.6% reduction in

nonresident visitation to the GYA. The 50 trip redistribution per day, divided between

adjacent lands on the west and north sides of YNP would be negligible. Users displaced

from the Teton Park Road and the surface of Jackson Lake would amount to an average

of 45 to 50 snowmobile trips per day, either entering YNP or going elsewhere on the

Targhee, Shoshone, or Bridger Teton National Forests. Some local displaced use would

enter the parks at other gateways and not impact adjacent lands. The level of congestion

and conflicts currently identified on all adjacent lands could improve due to lower use by

nonresident snowmobilers.

The NPS has estimated that the closure of YNP to backcountry nonmotorized use could

displace 844 skiers per year. Based on the winter use survey results, about 5% of these

users would or may continue to visit the GYA to engage in this use. In this alternative

using the survey assumptions, an estimated 42 skiers annually would be displaced to

surrounding national forests or to GTNP. This would not appear to represent a

significant impact on adjacent national forests.

Alternative G

By virtue of closing the three park units to snowmobiles, total visitation to the GYA by

those who live outside the five-county area would be reduced by 33.4%. Local use could

be redistributed to adjacent lands, along with a percentage of nonresident visitors who

state they would return to the GYA in this use scenario. The NPS estimates this amount

to be about 5,230 snowmobile trips over the season, 65 snowmobile trips daily. This

level of redistribution would appear to be easily absorbed in the total use for all national

forests in the GYA. The overall cumulative impact would be a decrease in use on

adjacent lands because of a 33.4% reduction in nonresident visitation to the GYA (which

is 80% of the current winter visitation). This reduction is a net change. It takes into

account visitors who said they would visit more often in this circumstance, and those

who said they would visit the same, but shift their use to other areas of the GYA (e.g.,

from the parks to the national forests).
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RELATIONSHIP BETWEEN LOCAL SHORT-TERM USES AND LONGTERM PRODUCTIVITY

In the context of the proposed action, short-term local uses would be those actions that

could be implemented under the alternatives for programmatic park plans. The EIS

planning effort addresses and discloses effects of alternative strategies for long-term

management. The plan to be arrived at in the Record of Decision will set goals and

objectives for management based on the alternatives evaluated in the EIS. Technically,

no site-specific activities are approved through this process (Decision to be Made) and

other discussions of programmatic planning in Chapter I). They would require additional

environmental analysis before implementation.

All the activities implied in the EIS alternatives could be considered local and short term,

in that they are specific to the three park units and are reversible actions. Long-term

productivity is construed as the continued existence of the natural resources of the parks,

at a sustainable and high level of quality, so that they can retain their inherent value and

be enjoyed by the public. Depending on the magnitude, extent, and duration of impacts

caused by short-term uses, long-term productivity could be affected.

The analysis in this DEIS has shown few impacts from possible short-term uses that

would affect long-term productivity as defined. It is the function of monitoring and

mitigation, incorporated into park management, to ensure no such impacts result from

implementation. Adaptive management is a dominant theme in two alternatives

(alternatives B and E). Adaptive management addressed this relationship (monitoring

and management) directly and programmatically. Otherwise every alternative would

induce short-term effects on a variety of experiential values or resources that would

persist for as long as the impacting activity is undertaken. Programmatic changes in

opportunities affecting visitor experience and use (the “enjoyment” part of the mission)

would continue for the duration of plan implementation.

Four areas of potential long-term impacts are identified in the analysis.

• Continued management with unregulated backcountry use in GTNP could, without

mitigation, further the decline of the bighorn sheep population in the park in conjunction

with other impacts.

• The cumulative effect of all park recreational uses on geothermal features could, without

mitigation, cause a long-term decline in this resource.

• The cumulative effect of all park recreational use could, without mitigation, affect listed

threatened and endangered species or species of special concern.

• The cumulative effect of air pollutants, including continued emissions from 2-stroke

engines stored in winter snowpacks, could be routed into aquatic systems and stored

biologically or physically. Over time this would represent a change in intrinsic natural

park values associated with those systems. The possible extent of such a change, or the

amount of indirect impact relative to any existing standard, cannot be determined at this

time.
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473

IRREVERSIBLE AND IRRETRIEVABLE COMMITMENTS OF RESOURCES

An irreversible commitment of resources is defined as the loss of future options. The

term applies primarily to the effects of using nonrenewable resources, such as minerals or

cultural resources, or to those factors, such as soil productivity that are renewable only

over long periods. It also could apply to the loss of an experience as an indirect effect of

a “permanent” change in the nature or character of the land.

An irretrievable commitment of resources is defined as the loss of production, harvest, or

use of natural resources. The amount of production foregone is irretrievable, but the

action is not irreversible. If the use changes, it is possible to resume production. An

example of such a commitment would be the loss of cross-country skiing opportunities

consequent to a decision allocating an area to snowmobile use only. Should the decision

be changed, skiing experiences, though lost in the interim, would be available again.

From an economic or social perspective, there would be no irreversible commitment of

resources from any of the alternative actions. However, alternatives to the current

management situation that change recreational opportunities or affect visitors by

displacing them from accustomed usage, would involve irretrievable losses. By the

nature of alternative actions, those losses would be balanced by a gain in some other

opportunity or resource benefit. Any perceived losses or tradeoffs in recreational

opportunities would have both social and economic consequences that would be

irretrievable, but not irreversible.

For example, the plowing of the road from West Yellowstone to Old Faithful in

alternative B would cause an irretrievable but not irreversible loss of snowmobiling and

snowcoach experiences along that section of road. Secondary effects of this decision

could be the irretrievable loss of income to businesses in West Yellowstone dependent on

these uses. The loss would not be irreversible because new business opportunities could

be available in providing for the alternative modes of access to Old Faithful by bus and

shuttle.

By virtue of the alternative actions, which are fully within the protective orientation of

the national park mission, and the analysis of effects from them, there would be no

irretrievable commitments of any resources. No environmental consequences have been

determined that involve the permanent loss of a resource or jeopardy to the existence of

any species on the basis of the proposed actions alone. Were it indicated that the

presence of existing or proposed levels of snowmobile trail use could cause grizzly bear

mortality, then there would be a risk of irreversible and irretrievable commitment of

resources. As stated, no such impacts were determined in this analysis.

The proposed action and alternatives prescribe changes from the existing condition for

different mixes of winter visitor experience. The changes are intended to address the

purpose and need for action described in Chapter I, while sharply defining the public’s

issues about the proposal. In some alternatives, the consequences of those changes
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improve the quality or condition of the parks’ experiential values and resources. This

includes improving values like air quality, sound versus natural quiet, wildlife species

and habitat, and recreation experiences (motorized and nonmotorized) whose quality is

dependent on those values. The achievement of such improvements is accompanied by

some tradeoff in another aspect of winter recreation such as loss of access (motorized and

nonmotorized), altering available modes of transport, redistribution of use, or regulating

types of equipment allowed. All these changes or tradeoffs would be associated with an

irretrievable loss of the kind indicated. Conversely, for alternatives that optimize access

and provide a full range of winter recreation activities, there would be tradeoffs

representing irretrievable losses in types and qualities of other visitor experiences. For

the range of alternatives a variety of irretrievable resource commitments would be made,

but none would be irreversible.

UNAVOIDABLE ADVERSE IMPACTS

The reader is referred to the previous two summary discussions. It should be clear from

these discussions that every alternative, including continuation of the current

management plan, would result in some impacts. Impacts for alternatives disclosed in

Chapter IV range from major adverse to major beneficial relative to alternative A.

Impacts are discussed for human health and safety, the economic and social environment,

physical and biological resources, and the experiential environment of the three parks.

These elements are interrelated and interdependent, as is the nature of any ecosystem

process and the human role in it. Therefore, the alternatives taken together display

consequences, tradeoffs, benefits, impacts, and opportunity costs in a way that reveals the

interdependent working of human and natural park systems.

This means that, considering the human use and enjoyment function (i.e., recreation), an

adverse impact from one perspective is often a benefit from another. Therefore, this

discussion dismisses further consideration of visitor experience and social concerns,

recognizing that there would be unavoidable adverse impacts (from minor to major)

across the range of alternatives and the associated range of human perceptions.

Potential unavoidable adverse economic impacts on the regional economy are readily

discussed for several alternatives, especially due to the local loss of motorized, oversnow

opportunities in the parks. None of these impacts could be considered irreversible or

long term in the context of the total economy. For some individual businesses, the

effects may be more drastic. It is, however, in the nature of business to start or change

course based on economic self-interest and survival. Long-term economic impacts are

not easy to determine because of this dynamic, and because the business world is

adaptable and creative. So, as indicated in the analysis, it is possible that the negative

regional impacts of some alternatives could be offset by a change in the type and mix of

visitors coming to the parks.

Potential unavoidable adverse impacts on physical and biological resources are disclosed

throughout the range of alternatives. These include impacts on air quality, wildlife
CUMULATIVE IMPACTS ANALYSES

475

displacement and habituation, water resources, and natural quiet. For the most part, any

such impacts are short term (for the duration of the impact cause) and minor. Other

possible minor to moderate impacts would be mitigated or avoided by the features of the

alternatives or the recommended mitigation measures expressed in specific analyses.

Current impacts on human health and safety represent a major part of the purpose and

need for action. Considering the existing condition described in Chapter III, most

alternatives represent an attempt to improve factors relating to health and safety. The

focus on health and safety is three-pronged: air quality and emissions from

snowmachines; motor vehicle accidents and behavior of various recreating user groups;

and inherent risks of winter recreation (avalanches). The desired impact is beneficial in

reducing these factors. Allowing the range of winter recreational use and access, which

is implicit in the purpose and need, carries with it unavoidable potential for accidents.

Unavoidable impacts are referred to in the beginning of Effects Common to all

Alternatives, Chapter IV. These result from winter use of the parks at any level, and they

include impacts on: natural soundscape; wildlife (collisions, displacement); safety; and

visitor experience.

CUMULATIVE IMPACTS ANALYSES

Assumptions and Methodology

The alternative programs or plans describe actions that are either larger in scale

addressing programmatic direction, or they are represented as examples of activities that

could occur. Generally, before such actions could be implemented, further site-specific

environmental analysis would be necessary. Therefore, this DEIS evaluates cumulative

impacts in the context of programmatic actions proposed in the alternatives, and

definitive cumulative impact analysis would be conducted later when site-specific

proposals are made and site-specific effects are determined.

Cumulative impacts analysis considers the degree to which any direct or indirect effects

from proposed actions adds to or detracts from the possible effects of other past, present,

or reasonably foreseeable actions. Since effects of actions are specific to each resource,

the types of actions and overall nature of impacts considered in this analysis are disclosed

by resource. Each resource is associated with a specific area of concern, and with impact

sources that could affect the resource within that area. If an action or an alternative could

have a direct or indirect effect on the resource, then this effect is considered additively

with the effects of other impact sources. Conversely, if an action does not have a direct

or indirect effect on a resource, no additive cumulative effect exists.

The Cumulative Impact section for each resource expresses the magnitude of the additive

impact of any direct or indirect effects for an alternative, if any, relative to the total

impact in the area of concern. Programmatically, the alternatives share the same mix of

activities, but to greater or lesser degrees. Therefore, the alternatives do not vary greatly
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in terms of general cumulative impacts. Where variations do occur between alternatives,

they are noted.

Geothermal Features

Area of Concern. The area of concern includes all geothermal features within the

boundaries of YNP. It does not include GTNP or the Parkway.

Potential Impact Sources. The nature of the concern is surface damage to geothermal

features. Surface damage can occur from trampling by wildlife and by pedestrian visitor

use in the summer. Acts of vandalism that add litter and other materials to thermal

features tend to destabilize the physical function of these important resources. Decisions

from other park planning projects such as the Commercial Services Plan may add

additional visitor use to geothermal areas throughout the year. Overall, the use trend is

increasing in the foreseeable future.

Additional Impact of the Proposed Actions. Under current winter use management,

minor direct adverse impacts could occur to features near the groomed surfaces for both

motorized and nonmotorized uses. Backcountry thermal features sustain minor adverse

impacts from skiers. Certain individual features may be at risk, but not predominantly

associated with winter recreational use. Under alternative B, there may be increased

impacts to the Old Faithful area if winter pedestrian use increases due to enhanced access

for this type of visitor. Similarly, in alternative C, with an increase in the type and

amount of use and longer seasons, wildlife use of geothermal winter ranges could be

moderately affected. In alternative F, since there would be the potential for fewer

adverse impacts to geothermal features located along roads closed to use, the overall

cumulative impact would be less. In alternative G, there may less overall impacts with

the use of mass transit and interpretive opportunities throughout the park. The additive

impacts of winter use appear to be relatively small compared to other existing impact

sources. The total cumulative effect for all alternatives lies in the range of acceptable

impacts with continued administration, trail location, and education. Without mitigation,

there could be long-term adverse impacts on individual geothermal features from all

impact sources.

Water Resources

Area of Concern. The area of concern includes all watershed areas contributing to water

resources within the three national park units. Most surface water hydrologic systems for

these park lands originate within the national parks and flow outward onto land owned by

other entities. Exceptions to this include headwater streams flowing into Yellowstone

Lake from the southeast, and into GTNP from the east. These arise out of predominantly

wilderness headwaters on the Bridger-Teton NF. Some of the inflows to GTNP flow

through private land inholdings or adjacent private lands. The area of concern is

delimited to the outflow boundaries of watersheds from the national parks.

Potential Impact Sources. Current impact sources within the national parks that may

affect water resources during the winter include emissions from 2-stroke engines that are
CUMULATIVE IMPACTS ANALYSES

477

deposited in snow and ice packs. Other winter sources include emissions from wheeledvehicles that operate on open roads within the parks and backcountry nonmotorized uses

that generate human wastes. During other seasons, deposition of petroleum products

onto road surfaces from large volumes of traffic can be washed as stormwater into

connected surface water systems. Land management activities within parks such as road

reconstruction and domestic livestock grazing (GTNP), sand and gravel sources, water

use and treatment facilities, and backcountry summer use are also possible impact

sources.

Other activities in the park contribute to decreases in water quality and may negatively

affect aquatic resources. According to the GTNP Park Resource Management Plan (NPS

1985 and 1995) and the recent Water Resources Scoping Report for GTNP (Mott 1998),

water resource issues in the park include high visitor use in the backcountry that results

in human fecal contamination, illegal dumping of sewage from boats. Other issues are

irrigation practices and water flows and discharge of sewage effluents to ground water.

Snowmobile emissions would appear to add a small increment of pollution to other more

significant water quality impacts. In YNP inadequate facilities for dealing with sewage

are of great concern, and efforts are underway to improve them.

Impact sources from upstream watersheds on adjacent national forest lands do not

generally include timber harvest, road construction, or impacts from other legitimate

multiple uses of those lands. Since the contributing watersheds are mostly in wilderness,

sources could include summer backcountry recreation, wildfire burned areas, and

grazing. Private lands adjacent to GTNP could contribute domestic waste, runoff from

grazed lands and roads connected to the stream systems. There are no foreseeable

changes to this scenario, other than the possibility of lost open space on private lands in

or adjacent to GTNP.

Additional Impact of the Proposed Action. Under current winter use management,

there has been no measurable impact to water resources or aquatic environments.

Therefore, there is no demonstrable addition to the total cumulative impact from other

possible sources. The only identifiable potential for additive impact is associated with

aquatic mechanisms that could trap non-biodgradable petroleum products, such as lake

and reservoir sediments and riparian vegetation. There is no evidence this occurs, but

future monitoring should incorporate this study as an objective. In alternative B no net

change in cumulative impact would occur. However, there may be a decrease in possible

adverse impacts on the Madison River from 2-stroke emission pollutants, as well as an

increase in turbidity from sand washing off roadways and entering connected streams. In

alternative C, additional amounts of sand could enter the Madison watershed from the

Gibbon River when the road along the Gibbon River is plowed. However, fewer

pollutants may enter the same watershed because 2-stroke engines will use this road

segment one month less in the winter. In alternative D a marginal improvement to the

parks’ watershed could occur in the long term as reduced emission standards are required

for 2-stroke engines in the year 2008-2009. In alternative G elimination of snowmobiles
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in the three park units could significantly reduce the risk of degrading water quality or

affecting aquatic resources in these headwater watershed areas.

Based on current information, the additive impact on water resources from winter use in

all alternatives would not add significantly to overall cumulative impacts. The ability of

motorized winter users to purchase bio-based fuels and lubricants in and near the parks

may be marginally beneficial by reducing deposition of pollutants into snowpacks.

Recommended mitigation is to move some roads away from paralleling rivers to

disconnect impact sources from hydrologic systems. The overall cumulative effect of all

sources over time has a long-term impact by changing the inherent quality or value of

aquatic resources.

Air Quality

Area of Concern. The area of concern includes the airshed described by all three park

units and by adjacent Class I areas on national forests. Although ambient air pollution

generated at great distances beyond the park boundaries are a concern relative to air

quality in the park, it is unreasonable to consider the whole of the western United States

as an area of concern. Additional pollution comes from regional industry located within

150 km of the park. Industries include oil and gas processing, power plants, and

industrial combustion. Levels of nitrates found in YNP’s snowpack can be related to

regional industry (Ingersol et al. 1997). Relative to these and other more distant ambient

sources, any additional pollution contributed through winter recreational use in the parks

is negligible.

Potential Impact Sources. Current impact sources within the parks that could affect

park air resources during the winter include emissions from 2-stroke engines and other

motorized wheeled-vehicles (or internal combustion engines) that operate on open roads

within the parks, as well as wood-burning stoves. During other seasons, human-related

sources of pollution include motor boats, gasoline powered maintenance equipment,

recreational vehicles, busses, generators, ambient sources, automobiles, campfires, and

road material processing equipment. Forest fires in both parks and national forests

impact air quality during the summer and fall seasons. There is no known connection

between potential sources of air pollution in the winter and potential sources in the

summer. Therefore, these sources are not additive as cumulative effects. Effects on

vegetation, or other air quality related values from auto emissions are largely

hypothetical. Such an impact could be attributed to the large amount of summer

automobile use when plants are actively respiring. In alternative G elimination of

snowmobiles could significantly reduce the risk of degrading air quality related values in

these Class I areas.
CUMULATIVE IMPACTS ANALYSES

479

Additional Impact of the Proposed Actions. In YNP and GTNP obvious visual effects

of air pollution are usually short term and local. The cumulative effect of winter use,

added to other possible sources of pollution in the parks, is considered to be short term

and localized around parking destination and staging areas, entrance stations, and

attractions such as Old Faithful. Effects other than visibility are of concern in these local

areas, including health impacts. In alternative B the application of “cleaner” technology

could result in a net reduction of cumulative impacts within the area of concern. This

would also be true of other alternatives that apply new technology aimed at meeting EPA

emission regulations. Conversely, in alternative C any increased use without

implementing new “clean” technology would continue present trends with air quality

impacts; that is, continued short-term and local negative impacts on visibility and air

quality parameters affecting human health. In any alternative, when ambient air quality

levels exceed existing standards, plans to correct the situation would be developed and

implemented.

Wildlife

Bison

Area of Concern. The area of concern is that which is used by bison for wintering and

seasonal migration. Generally, the area includes the corridor and adjacent available

winter forage areas in the northern area of YNP and into Montana, and the western

corridor along the Firehole and Madison River. The bison issues are mostly beyond the

scope of this analysis, and are being addressed in the Bison Management Plan/EIS

referred to in Other Plans and Environmental Analyses, Chapter I.

Potential Impact Sources. Since the area of concern is tied to bison winter habitat,

impact sources include winter uses — motorized and nonmotorized — that displace bison

from that particular habitat or render the habitat unusable for them. Activities such as

trail grooming that facilitate bison movement in the winter (with less energy expenditure)

also facilitate the recreational uses that can stress bison and cause higher energy

expenditures. Bison movement along groomed and open roads can lead to the complex

economic and social issue of migration to lands beyond park boundaries. Bison have

been shown, however, to leave the park more in response to a variety of circumstances,

and often not on groomed surfaces. For further evaluation of impact sources refer to the

Bison Management Plan/EIS. Actions being considered in the Bison EIS include closing

sections of road to winter motorized use and limiting bison use of groomed surfaces.

Additional Impact of the Proposed Actions. Proposed actions may be subject to

decisions made in the Bison Management EIS/Plan. For consideration of the total

cumulative impact on bison, and how winter use contributes to it, this analysis

incorporates the Bison Management EIS and Plan. Refer also to the disclosure of direct

and indirect effects earlier in this chapter.
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Ungulates other than Bison

Area of Concern. The area of concern includes habitat for various species within the

three park units and other seasonal habitat beyond the parks’ boundaries. Ungulate

species are migratory and some herd units will disperse onto adjacent jurisdictions and

land ownerships primarily for winter habitat and forage.

Potential Impact Sources. Other impact sources include those that might occur on

adjacent lands. This includes conflicts with other human use activities such as ranching,

hunting, and general recreation. Development on private lands, loss of open space

habitat, or road construction on other federal jurisdictions are other possible sources.

Within the parks, similar actions represent impact sources — housing and road

construction, grazing in GTNP, as well as increased recreational use. The most relevant

impact sources are those, which occur during the winter, on or off the parks.

The bighorn sheep herd in the Teton Range is declining. In 1999 the Bridger-Teton NF

concurred with its permittee, Jackson Hole Mountain Resort, to allow skiing outside the

ski area boundary. This makes skiing more accessible in areas occupied by wintering

bighorn sheep, and contributes downward pressures on the population.

Habitat losses through development on private lands or road construction on other federal

jurisdictions can affect herds that occupy the national parks seasonally. In some cases

such losses may render the herds more dependent upon habitat within the parks that is

marginally less effective for survival during harsh winters. In this situation, the presence

of other impact sources within the parks is critical to herd survival.

Additional Impact of the Proposed Actions. The direct and indirect effects described

for winter uses in the parks are key limiting elements for cumulative impacts. Stressed

animals or herds whose winter forage options have become limited are likely to be

affected cumulatively, through the additional impacts imposed by winter recreation use in

the parks. Alternatives that limit all winter recreational use to trails away from thermal

areas and close backcountry areas would decrease adverse cumulative impacts on

ungulates. Backcountry nonmotorized uses could exacerbate unmitigated, long-term

impacts on bighorn sheep in GTNP. In alternative G closure of backcountry areas

important as bighorn sheep habitat would help reduce the total cumulative effect.

Federally Protected Species

The type of cumulative effects analysis for federally protected species required in an EIS

differs from that required in a Biological Assessment (BA). In a BA cumulative effects

include the effects of future State, tribal, local, or private actions that are reasonably

certain to occur in the action area. Future federal actions that are unrelated to the

proposed action are not considered (FWS 1998). In an EIS cumulative effects include all

reasonably foreseeable future actions regardless of what agency (federal or nonfederal)

undertakes such other actions (40 CFR § 1508.7).

Areas of Concern. For threatened and endangered species, the areas of concern include:
CUMULATIVE IMPACTS ANALYSES

481

• The GYA grizzly bear recovery area.

• Existing effective wolf habitat within the three park units.

• Juxtaposed bald eagle nesting and forage areas within the three parks.

• Lynx habitat within the parks.

Potential Impact Sources. Potential impact sources within the areas of concern include

any developed facilities or opportunities for human conflict with any of these species

when they are present. In the winter this includes any human use near dens, nests, or

food sources. For example, impacts to predator species are linked with impacts to

ungulates.

Additional Impacts of the Proposed Actions. Potential winter impacts are not

considered additive to other impacts that occur at other times and places within the area

of concern. Therefore, cumulative impacts equate to those direct and indirect effects

from winter use disclosed for these species earlier in this chapter. Most alternatives

include activities that take place while bears are inactive for the winter. Therefore any

conflicts associated with bears would be minor. Therefore, the additional impact under

any alternative would be minor or negligible.

Ungulate management in the parks may affect availability of prey and wolves overall.

The draft Bison Management EIS/Plan could affect wolves by reducing its prey base

through management removals. In terms of the additional impact of winter use, all

alternatives would have negligible or minor impacts on wolves.

Eagle populations are increasing in the GYA under the influence of, or unaffected by,

current land management. Additional impacts of the winter use alternatives in the area of

concern would be minor or negligible. Nest areas are currently protected in all the parks.

Lynx habitat within the area of concern is fragmented under existing management. None

of the alternatives contribute to any greater fragmentation. The effects under existing

management are minor or negligible — actions in other alternatives would not add to this

condition and could improve it. Existing management includes various practices and

measures that mitigate potential habituation and mortality.

Species of Special Concern

Areas of Concern. For all species of special concern, the area considered for cumulative

impact assessment, is the collective habitat within the boundaries of the three park units.

Potential Impact Sources. Land use development, including additional commercial

services development within the park units, impacts the survival of wolverine and fisher

populations. Future road construction or developments in YNP as outlined in the

Commercial Services Plan may occur in ungulate winter range. Road construction within

YNP could further fragment wolverine and fisher use of home ranges. Commercial

developments in ungulate winter range could affect carcass availability, and decrease
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482

available habitat to wolverines and fishers. Hunting and habitat destruction outside the

parks has impacted trumpeter swans.

Additional Impacts of the Proposed Actions. In YNP, increased backcountry skiing in

remote, high elevation areas could cause displacement of wolverines into less suitable

habitats. In YNP this is mitigated in the alternatives (B, D, and E) that limit backcountry

skiing to designated routes and trails only; the impact is eliminated in alternative F,

which closes the backcountry. In GTNP closures to protect bighorn sheep may be of

benefit to wolverines as well. Additional impacts of winter use under all other

alternatives are no greater than those occurring under current management. All

alternatives would have minor or negligible impacts. Alternatives D and F could

improve habitat by removing oversnow trails for motorized use that tend to fragment

winter habitat.

Sound

Areas of Concern The area considered for cumulative impact assessment, is the natural

soundscape within the boundaries on three park units.

Potential Impact Sources Since individual sources of sound are transient and short

lived, the potential cumulative impact on the winter soundscape is those sounds occurring

during that time. Sounds other than those that naturally occur in the park units during the

winter include the sound of wheeled vehicular traffic along open roads, the sound of

oversnow vehicles on groomed routes, aircraft overflights, and sounds attendant to

facility developments open in the winter.

Additional Impacts of the Proposed Actions Where open facilities coincide with roads

and oversnow motorized activities, the natural soundscape is impacted. There are such

areas in the parks where the total cumulative effect is such that it renders the natural

soundscape to be seldom evident for most of a winter day.

Cultural Resources

There would be no new cumulative impacts to cultural resources as a result of the

continuing existing management.

For All Other Alternatives. Proposed construction could put archeological resources at

risk. Such impacts would be mitigated to the fullest extent possible through avoidance

and/or data recovery. A loss of historic fabric in structures that undergo adaptive

rehabilitation could occur. The construction of visitor facilities, trailheads and trails, or

camping sites could intrude upon potential cultural landscapes.
483
GLOSSARY

484

GLOSSARY

Act: The National Environmental Policy Act, as amended (42 U.S.C. 4321, et seq.) which is also referred

to as “NEPA.” (40 CFR §1508.2)

Activity: Action, measures, or treatments that are undertaken which directly or indirectly produce, enhance

or maintain forest and rangeland outputs, or achieve administrative or environmental quality objectives.

Ambient sources: As applied to air quality, or natural soundscape, ambient sources are those that make up

the background characteristics or the environmental baseline. They are sources of emissions or sound that

are not generated locally, but rather at a distance and are unrelated to local sources of emissions or sounds.

Bear-human conflict: In the parks, conflicts include injury or death to humans or livestock, damage to

property, or the obtaining of human food. Conflicts outside of the parks also include damage to orchards,

gardens, and beehives.

Bear-human confrontation: Interactions between humans and bears that include bluff charges or other

threatening behaviors, or result in the displacement of bears in response to humans.

Categorical Exclusion: A category of actions which do not individually or cumulatively have a significant

effect on the human environment and which have been found to have no such effect in procedures adopted

by a Federal agency in implementation of these regulations (40 CFR §1507.3) and for which, therefore,

neither an environmental assessment nor an environmental impact statement is required. (40 CFR §1508.4)

CEQ : Council on Environmental Quality.

CFR: Code of Federal Regulations.

Connected Actions: (40 CFR §1508.25) Actions are connected if they:

(i) Automatically trigger other actions that may require environmental impact statements.

(ii) Cannot or will not proceed unless other actions are taken previously or simultaneously.

(iii) Are interdependent parts of a larger action and depend on the larger action for their justification.

Cooperating Agency : Any Federal agency other than a lead agency which has jurisdiction by law or

special expertise with respect to any environmental impact involved in a proposal (or a reasonable

alternative) for legislation or other major Federal action significantly affecting the quality of the human

environment. The selection and responsibilities of a cooperating agency are described in 40 CFR §1501.6.

A State or local agency of similar qualifications or, when the effects are on a reservation, an Indian Tribe,

may by agreement with the lead agency become a cooperating agency. (40 CFR §1508.5)

Council: The Council on Environmental Quality established by Title II of the Act. (40 CFR §1508.6)

Cumulative Actions: Actions, which when viewed with other proposed actions have cumulatively

significant impacts and should therefore be discussed in the same impact statement. (40 CFR §1508.25)

Cumulative Impact: The impact on the environment which results from the incremental impact of the

action when added to other past, present, and reasonably foreseeable future actions regardless of what

agency (Federal or non-Federal) or person undertakes such other actions. Cumulative impacts can result

from individually minor but collectively significant actions taking place over a period of time. (40 CFR

§1508.7)
485

Decision Document : A record of decision, decision memo, or decision notice.

Decision Memo : A concise written record of the responsible official's decision to implement an action that

has been categorically excluded from documentation in an environmental impact statement or

environmental assessment.

Decision Notice: A concise written record of the responsible official's decision based on an environmental

assessment and a finding of no significant impact.

Displacement — Recreation: The movement of recreation visitors from a preferred recreation site or area

due to conflicts with other users, crowding, or management action.

Displacement — Wildlife: Wildlife movement away from areas of human activity. Displacement may be

temporary (until the activity ceases) or long-term. Long term displacement results in avoidance of certain

habitats, and consequently may be especially adverse.

Ecosystem: Living organisms (biotic) together with their non-living (abiotic) environment, both forming

an interactive system within an identifiable space or area.

Effects: (40 CFR 1508.8) These include:

(a) Direct effects, which are caused by the action and occur at the same time and place.

(b) Indirect effects, which are caused by the action and are later in time or farther removed in distance, but

are still reasonably foreseeable. Indirect effects may include growth inducing effects and other effects

related to induced changes in the pattern of land use, population density or growth rate, and related effects

on air and water and other natural systems, including ecosystems. Effects and impacts as used in these

regulations are synonymous. Effects includes ecological (such as the effects on natural resources and on

the components, structures, and functioning of affected ecosystems), aesthetic, historic, cultural, economic,

social, or health, whether direct, indirect, or cumulative. Effects may also include those resulting from

actions that may have both beneficial and detrimental effects, even if on balance the agency believes that

the effect will be beneficial.

(c) Cumulative, see cumulative impact.

Endangered Species: Any species (flora or fauna) classified by the U.S. Department of the Interior as being

in danger of extinction throughout all or a significant portion of its range (not including insects determined

to be pests).

Enjoyment: As used in NPS Management Policies , “enjoyment” means to derive benefit (including

scientific knowledge) or inspiration from a park, and includes enjoyment both by people who directly

experience the park and by those who appreciate it from afar.

Environmental Analysis: An investigation of a proposed action and alternatives to that action and their

direct, indirect, and cumulative environmental impacts; the process which provides the necessary

information for reaching an informed decision and the information needed for determining whether a

proposed action may have significant environmental effects and determining the type environmental

document required.

Environmental Assessment: (40 CFR §1508.9)

(a) a concise public document for which a Federal agency is responsible that serves to:

(1) Briefly provide sufficient evidence and analysis for determining whether to prepare an

environmental impact statement or a finding of no significant impact.

(2) Aid an agency's compliance with the Act when no environmental impact statement is necessary.

(3) Facilitate preparation of a statement when one is necessary.

(b) Shall include brief discussions of the need for the proposal, of alternatives as required by section

102(2)(E), of the environmental impacts of the proposed action and alternatives, and a listing of

agencies and persons consulted.
GLOSSARY

486

Environmental Document: Includes the documents specified in 40 CFR §1508.9 (environmental

assessment), 40 CFR §1508.11 (environmental impact statement), 40 CFR §1508.13 (finding of no

significant impact), and 40 CFR §1508.22 (notice of intent). (40 CFR §1508.10)

Environmental Impact Statement (EIS): A detailed written statement as required by section 102(2)(C) of

the Act (40 CFR §1508.11). May be a Draft EIS (DEIS) that has been published and is available for public

comment, or a Final EIS (FEIS) that has been produced following the public comment period. The primary

purpose of an EIS is to serve as an action-forcing device to insure that the policies and goals defined in the

Act are infused into the ongoing programs and actions of the Federal Government. It shall provide full and

fair discussion of significant environmental impacts and shall inform the decision makers and the public of

the reasonable alternatives, which would avoid or minimize adverse impacts or enhance the quality of the

human environment. Agencies shall focus on significant environmental issues and alternatives and shall

reduce paperwork and the accumulation of extraneous background data.

Environmentally Preferable Alternative: An alternative that best meets the goals of section 101 of the

National Environmental Policy Act and required by 40 CFR §1505.2(b) to be identified in a record of

decision. Ordinarily, this is the alternative that causes the least damage to the biological and physical

environment and best protects, preserves, and enhances historical, cultural, and natural resources. In some

situations, there may be more than one environmentally preferable alternative.

Extraordinary Mitigation: Mitigation measures that are above and beyond the standard mitigation required

for a particular activity. Standard mitigation is often inferred by agency standards and/or guidelines, and

generally must be applied under any circumstances, or is represented by generally accepted practices such

as soil and water conservation measures.

Federal Agency: All agencies of the Federal Government. It does not mean the Congress, the Judiciary, or

the President, including the performance of staff functions for the President in his Executive Office. (40

CFR §1508.12)

Finding of No Significant Impact (FONSI): A document by a Federal agency briefly presenting the reasons

why an action, not otherwise excluded (40 CFR §1508.4), will not have a significant effect on the human

environment and for which an environmental impact statement therefore will not be prepared. It shall

include the environmental assessment or a summary of it and shall note any other environmental documents

related to it (40 CFR §1501.7(a)(5)). (40 CFR §1508.13)

Floodplains : As defined by EO 11988, as amended, lowland and relatively flat areas adjoining inland and

coastal waters including flood prone areas of offshore islands, including at a minimum, that area subject to

a 1% or greater chance of flooding in any given year.

Flush: An immediate, short-term behavioral response to disturbance that includes flight or running from a

perceived threat.

Habituation : The process by which an animal becomes desensitized to a particular stimulus. In this

document, habituation refers to wildlife that have lost their innate wariness of humans, usually in response

to a positive association such as obtaining food. Animals typically habituate to stimuli that are predictable

and nonthreatening, such as highway traffic and routine sounds.

Human Environment: Shall be interpreted comprehensively to include the natural and physical

environment and the relationship of people with that environment...This means that economic or social

effects are not intended by themselves to require preparation of an environmental impact statement. When

an environmental impact statement is prepared and economic or social and natural or physical

environmental effects are interrelated, then the environmental impact statement will discuss all of these

effects on the human environment. (40 CFR §1508.14)

Impairment : As used in NPS Management Policies , The “impairment” means an adverse impact on one or

more park resources or values that interferes with the integrity of the park’s resources or values, or the

opportunities that otherwise would exist for the enjoyment of them, by the present or a future generation.

Impairment may occur from visitor activities, NPS activities in managing a park, or activities undertaken

by concessioners, contractors, and others operating in a park. As used here, the impairment of park

resources and values has the same meaning as the phrase “derogation of the values and purposes for which

these various areas have been established,” as used in the General Authorities Act.
487

Interdisciplinary Team: A group of individuals with skills from different resource areas. An

interdisciplinary team is assembled to develop environmental analysis for a proposed action, in accordance

with NEPA.

Irretrievable: A term that applies to the loss of production, harvest, and consumptive or nonconsumptive

use of natural resources. For example, recreation experiences are lost irretrievably when an area is closed

to human use. The loss is irretrievable, but the action is not irreversible. Reopening the area would allow a

resumption of the experience.

Irreversible: A term that describes the loss of future options. Applies primarily to the effects of use of

nonrenewable resources, such as minerals or cultural resources, or to those factors, such as soil productivity

that are renewable only over long periods of time.

Issue: A point of debate about the environmental effects of a proposed action. See also Significant Issue.

Jurisdiction by Law: Agency authority to approve, veto, or finance all or part of the proposal (40 CFR

§1508.15). See also cooperating agency.

Lead Agency: The agency or agencies preparing or having taken primary responsibility for preparing the

environmental impact statement. (40 CFR §1508.16) This also applies to environmental assessments. See

also, joint lead agencies (40 CFR §1506.2(4)(c)).

Legislation: A bill or legislative proposal to Congress developed by or with the significant cooperation and

support of a Federal agency, but does not include requests for appropriations. The test for significant

cooperation is whether the proposal is in fact predominantly that of the agency rather than another source.

Drafting does not by itself constitute significant cooperation. Proposals for legislation include requests for

ratification of treaties. Only the agency that has primary responsibility for the subject matter involved will

prepare a legislative environmental impact statement. (40 CFR §1508.17)

Major Federal Action: (40 CFR §1508.18) Includes actions with effects that may be major and which are

potentially subject to Federal control and responsibility. Major reinforces but does not have a meaning

independent of significantly (40 CFR §1508.27). Actions include the circumstance where the responsible

officials fail to act and that failure to act is reviewable by courts or administrative tribunals under the

Administrative Procedure Act or other applicable law as agency action.

(a) Actions include new and continuing activities, including projects and programs entirely or partly

financed, assisted, conducted, regulated, or approved by federal agencies; new or revised agency rules,

regulations, plans, policies, or procedures; and legislative proposals (40 CFR §1506.8, §1508.17).

Actions do not include funding assistance solely in the form of general revenue sharing funds,

distributed under the State and Local Fiscal Assistance Act of 1972, 31 U.S.C. 1221 et seq., with no

Federal agency control over the subsequent use of such funds. Actions do not include bringing judicial

or administrative civil or criminal enforcement actions.

(b) Federal actions tend to fall within one of the following categories:

(1) Adoption of official policy, such as rules, regulations, and interpretations adopted pursuant to the

Administrative Procedure Act, 5 U.S.C. 551 et seq.; treaties and international conventions or

agreements; formal documents establishing an agency's policies which will result in or

substantially alter agency programs.

(2) Adoption of formal plans, such as official documents prepared or approved by federal agencies

which guide or prescribe alternative uses of Federal resources, upon which future agency actions

will be based.

(3) Adoption of programs, such as a group of concerted actions to implement a specific policy or plan;

systematic and connected agency decisions allocating agency resources to implement a specific

statutory program or executive directive.

(4) Approval of specific projects, such as construction or management activities located in a defined

geographic area. Projects include actions approved by permit or other regulatory decision as well

as Federal and federally assisted activities.

Mitigation (40 CFR §1508.20):

(a) Avoiding the impact altogether by not taking a certain action or parts of an action.
GLOSSARY

488

(b) Minimizing impacts by limiting the degree or magnitude of the action and its implementation.

(c) Rectifying the impact by repairing, rehabilitating, or restoring the affected environment.

(d) Reducing or eliminating the impact over time by preservation and maintenance operations during the

life of the action.

(e) Compensating for the impact by replacing or providing substitute resources or environments.

NEPA Process: All measures necessary for compliance with the requirements of section 2 and Title I of

NEPA.

Notice of Intent: A notice that an environmental impact statement will be prepared and considered. (40

CFR §1508.22)

Park Resources and Values:Resources and values of a park whose conservation is essential to the purposes

for which the area was included in the national park system, including both the Organic Act’s fundamental

purpose for all parks, as supplemented and clarified by the General Authorities Act, and any additional

purposes stated in a park’s establishing legislation or proclamation. Under the Organic Act and the General

Authorities Act, these resources and values always include, but are not limited to, all of the following, to

the extent they are present in the park: the biological and physical processes that created the park and

continue to act upon it; scenic features; natural landscapes; natural sounds and odors; water and air

resources; soils; geological resources; paleontological resources; archeological resources; cultural

landscapes; ethnographic resources; historic and prehistoric sites and structures; museum collections; native

plants and animals; clear daytime vistas and night skies. The term also includes opportunities to experience

enjoyment of the above resources and values, to the extent that can be done without impairing any of them.

“Park resources and values,” as used in Management Policies , do not include any attributes of a park whose

conservation is not essential to the purposes for which a park was designated. For example, the term does

not include non-native species or man-made structures that are not historic or prehistoric, unless their

conservation is essential to a specific additional purpose for which an individual park was established.

Preferred Alternative: The alternative(s) which the agency believes would best fulfill its statutory mission

and responsibilities, giving consideration to environmental, social, economic, and other factors and

disclosed in an environmental impact statement.

Programmatic EIS : An environmental impact statement designed to evaluate the relative effects of

alternative plans or programs that will guide or prescribe alternative uses of Federal resources, upon which

future agency actions will be based.

Programmatic Plan: A major Federal action, developed through the NEPA process, upon which future

agency actions will be based. An EIS is normally written to provide choices for prescriptions and

connected or related actions, whose eventual decision is the selected plan. See Major Federal Action.

Proposal: Exists at that stage in the development of an action when an agency subject to the Act has a goal

and is actively preparing to make a decision on one or more alternative means of accomplishing that goal

and the effects can be meaningfully evaluated... A proposal may exist in fact as well as by agency

declaration that one exists. (40 CFR §1508.23)

Proposed Action: A proposal made by the lead agency to authorize, recommend, or implement an action to

meet a specific purpose and need (see proposal).

Public Comment : Comments provided by interested or potentially affected parties on an environmental

document during an official comment period, as required in NEPA.

Scope: The range of actions, alternatives, and impacts to be considered in an environmental impact

statement. (40 CFR §1508.25)

Scoping: The procedure by which the agency identifies important issues and determines the extent of

analysis necessary for an informed decision on a proposed action. Scoping is an integral part of

environmental analysis.

Significant Issue: (see “issue”)... An issue that explicitly links the proposed action (or a feature of the

proposal) to a potential environmental effect. Significant issues are those that are determined to be

“deserving of study” (40 CFR §1500.4, §1501.7, and §1502.14) within the context of the purpose and need

for action, and can therefore become the basis for an alternative to the proposed action.

Significantly: This term includes both context and intensity (40 CFR §1508.27):
489

(a) Context. This means that the significance of an action must be analyzed in several contexts such as

society as a whole (human, national), the affected region, the affected interests, and the locality.

Significance varies with the setting of the proposed action. For instance, in the case of a site-specific

action, significance would usually depend upon the effects in the locale rather than in the world as a

whole. Both short- and long-term effects are relevant.

(b) Intensity. This refers to the severity of impact. Responsible officials must bear in mind that more than

one agency may make decisions about partial aspects of a major action. The following should be

considered in evaluating intensity:

(1) Impacts that may be both beneficial and adverse. A significant effect may exist even if the Federal

agency believes that on balance the effect will be beneficial.

(2) The degree to which the proposed action affects public health or safety.

(3) Unique characteristics of the geographic area such as proximity to historic or cultural resources,

park lands, prime farmlands, wetlands, wild and scenic rivers, or ecologically critical areas.

(4) The degree to which the effects on the quality of the human environment are likely to be highly

controversial.

(5) The degree to which the possible effects on the human environment are highly uncertain or involve

unique or unknown risks.

(6) The degree to which the action may establish a precedent for future actions with significant effects

or represents a decision in principle about a future consideration.

(7) Whether the action is related to other actions with individually insignificant but cumulatively

significant impacts. Significance exists if it is reasonable to anticipate a cumulatively significant

impact on the environment. Significance cannot be avoided by terming an action temporary or by

breaking it down into small component parts.

(8) The degree to which the action may adversely affect districts, sites, highways, structures, or

objects listed in or eligible for listing in the National Register of Historic Places or may cause loss

or destruction of significant scientific, cultural, or historical resources.

(9) The degree to which the action may adversely affect an endangered or threatened species or its

habitat that has been determined to be critical under the Endangered Species Act of 1973.

(10) Whether the action threatens a violation of Federal, State, or local law or requirements imposed

for the protection of the environment.

Similar Actions: Actions which when viewed with other reasonably foreseeable or proposed agency

actions, have similarities that provide a basis for evaluating their environmental consequences together,

such as common timing or geography. (40 CFR §1508.25)

Site-specific Actions : Actions that are specific and focused to a defined and limited place and time. In the

context of an analysis, site-specificity usually refers to the analysis of a specific project in a defined

geographic area, such as a construction project. Such projects are normally done in order to achieve the

goals and objectives that are defined in a plan that has been approved through NEPA in a “programmatic

EIS” and record of decision. See Programmatic EIS. See Major Federal Action.

Soundscape: The natural ambient soundscape is the aggregate of all the natural sounds that occur in parks,

together with the physical capacity for transmitting natural sounds. Natural sounds occur within and

beyond the range of sounds that humans can perceive and can be transmitted through air, water, or solid

materials. The natural ambient sound level — that is, the environment of sound that exists in the absence

of human-caused noise — is the baseline condition, the standard against which current conditions in a

soundscape will be measured and evaluated.

Special Expertise: Statutory responsibility, agency mission, or related program experience. (40 CFR

§1508.26). See also Cooperating Agency.

Tiering (40 CFR §1508.28): The coverage of general matters in broader environmental impact statements

(such as national program or policy statements) with subsequent narrower statements or environmental

analyses (such as regional or basinwide program statements or ultimately site-specific statements)

incorporating by reference the general discussions and concentrating solely on the issues specific to the

statement subsequently prepared. Tiering is appropriate when the sequence of statements or analyses is:
GLOSSARY

490

(a) From a program, plan, or policy environmental impact statement to a program, plan, or policy

statement or analysis of lesser scope or to a site-specific statement or analysis.

(b) From an environmental impact statement on a specific action at an early stage (such as need and site

selection) to a supplement (which is preferred) or a subsequent statement or analysis at a later stage

(such as environmental mitigation). Tiering in such cases is appropriate when it helps the lead agency

to focus on the issues that are ripe for decision and exclude from consideration issues already decided

or not yet ripe.
491
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INDEX

512

INDEX

Accommodations, lodging, xxix, 16, 28, 34, 123,

140, 190, 193, 213, 233, 317, 358, 431, 462,

497, 500, 557, 566, 574

Accommodations, parking, xxix, 27, 31, 52, 151,

159, 194, 195, 207, 209, 213, 214, 227, 245,

317, 322, 354, 355, 359, 395, 398, 400, 401,

431, 468, 548, 556, 558, 564, 585, 597

Accommodations, warming huts, ix, 27, 49, 51,

53, 55, 58, 62, 64, 65, 78, 210, 213, 215, 227,

250, 262, 297, 305, 317, 318, 337, 340, 343,

352, 353, 360, 362, 365, 374, 379, 382, 383,

386, 399, 403, 419, 421, 434, 435, 437, 450,

452, 463, 465, 481, 483, 485, 499, 501, 520,

523, 534, 537

Air quality, i, vii, viii, x, xiii, xiv, xvi, xxviii,

xxix, 4, 7, 8, 28, 32, 50, 52, 54, 57, 60, 65, 67,

69, 70, 78, 116, 121, 139, 141, 142, 143, 144,

145, 146, 147, 235, 241, 242, 243, 246, 247,

257, 264, 265, 266, 267, 268, 272, 275, 326,

369, 401, 407, 439, 460, 470, 509, 568, 569,

570, 571, 572, 575, 591, 592, 596, 597, 603,

613, 616, 618, 624, 625

Alternative A, i, xiii, xxvi, xxvii, xxix, 39, 48,

67, 72, 89, 103, 171, 173, 244, 246, 247, 250,

263, 264, 265, 266, 267, 269, 279, 280, 281,

282, 284, 285, 286, 287, 289, 292, 294, 297,

298, 299, 301, 303, 305, 313, 314, 315, 317,

318, 327, 328, 329, 331, 332, 335, 336, 337,

338, 339, 341, 342, 343, 344, 345, 346, 347,

360, 365, 366, 369, 370, 371, 372, 374, 377,

378, 379, 380, 381, 382, 384, 385, 386, 387,

388, 389, 401, 403, 404, 407, 408, 410, 411,

412, 415, 416, 417, 418, 419, 420, 421, 422,

423, 424, 425, 433, 439, 440, 441, 442, 443,

444, 446, 447, 448, 449, 450, 451, 452, 453,

454, 455, 460, 462, 464, 466, 470, 471, 472,

473, 474, 475, 478, 479, 480, 481, 482, 483,

484, 485, 486, 487, 488, 489, 499, 500, 501,

509, 511, 512, 513, 515, 516, 517, 518, 519,

520, 521, 522, 523, 524, 525, 526, 529, 535,

536, 542, 544, 547, 550, 552, 553, 557, 558,

559, 562, 568, 572, 575, 576, 583, 584, 585,

591

Alternative B, i, xiii, xxvi, xxvii, xxix, xxx, 50,

67, 91, 105, 241, 321, 322, 323, 324, 325, 326,

327, 328, 329, 330, 331, 333, 335, 336, 337,

338, 339, 340, 341, 342, 343, 348, 350, 351,

354, 355, 357, 360, 361, 362, 363, 364, 365,

367, 368, 369, 372, 373, 374, 378, 379, 383,

386, 395, 398, 399, 400, 401, 411, 415, 426,

431, 438, 443, 447, 460, 494, 507, 531, 537,

542, 543, 550, 552, 553, 554, 568, 569, 570,

571, 572, 573, 574, 575, 576, 580, 586, 590,

593, 595, 597

Alternative C, i, xiv, xxvi, xxvii, xxx, 54, 68, 93,

107, 359, 367, 368, 369, 370, 371, 372, 373,

374, 375, 377, 378, 379, 380, 381, 382, 384,

385, 386, 390, 391, 392, 393, 394, 396, 397,

398, 401, 403, 530, 536, 543, 552, 554, 569,

575, 577, 579, 586, 593, 595, 597

Alternative D, i, xiv, xxv, xxvi, xxvii, xxx, 39,

56, 57, 69, 95, 109, 351, 404, 405, 406, 407,

408, 410, 412, 414, 415, 416, 417, 418, 419,

420, 421, 426, 428, 429, 430, 432, 434, 435,

436, 438, 464, 494, 507, 516, 538, 543, 544,

554, 570, 571, 577, 583, 586, 595

Alternative E, i, xi, xv, xxvi, xxvii, xxx, xxxi, 11,

59, 62, 67, 70, 77, 78, 97, 438, 439, 440, 441,

442, 443, 444, 446, 447, 448, 449, 450, 451,

456, 458, 459, 460, 462, 464, 465, 467, 468,

474, 478, 487, 497, 502, 544, 557, 558, 570,

578, 587

Alternative F, i, xv, xxvi, xxvii, xxxi, 61, 71, 72,

99, 467, 468, 469, 470, 471, 472, 473, 474,

477, 479, 481, 482, 483, 485, 486, 490, 491,

493, 494, 495, 498, 499, 501, 502, 507, 544,

545, 559, 560, 571, 572, 573, 575, 579, 582,

587, 593, 600

Alternative fuels, 54, 57, 71, 241, 369, 407, 410,

440

Alternative G, i, xvi, xxvi, xxvii, xxviii, xxxi, 62,

70, 72, 73, 76, 77, 101, 113, 244, 246, 430,

502, 503, 504, 505, 506, 507, 508, 509, 510,

511, 513, 515, 516, 517, 518, 519, 520, 521,

522, 523, 526, 527, 528, 529, 530, 531, 532,

534, 535, 536, 537, 545, 562, 566, 572, 575,

576, 579, 580, 581, 583, 588, 594, 595, 596,

599

American Indians, vi, 12, 21, 24, 49, 52, 55, 58,

115, 116, 130, 200, 201, 203, 204, 208, 215,

231, 232, 256, 567, 603, 621

American Indians, Assiniboine, 22, 23, 204

American Indians, Blackfeet, 21, 200, 204

American Indians, Cheyenne River Sioux, 22,

23, 24, 204, 564
513

American Indians, Confederated Salish, 21, 23,

24, 200, 204

American Indians, Crow, 21, 22, 23, 200, 204

American Indians, Crow Creek Sioux, 22, 23,

24, 204, 564

American Indians, Flandreau Santee Sioux, 204

American Indians, Kiowa, 22, 204

American Indians, Kootenai, 21, 23, 24, 200,

204

American Indians, Lower Brule Sioux, 22, 204

American Indians, Nez Perce, 21, 23, 24, 200,

204

American Indians, Northern Arapahoe, 21, 200,

204

American Indians, Northern Cheyenne, 21, 200,

204

American Indians, Oglala Sioux, 22, 23, 24, 204

American Indians, Rosebud Sioux, 22, 23, 24,

204

American Indians, Shoshone-Bannock, 21, 24,

200, 204

American Indians, Shoshone-Eastern Band, 21,

200, 204

American Indians, Sioux, 22, 23, 24, 204, 564

American Indians, Sisseton-Wahpeton Sioux, 22,

23, 204

American Indians, Spirit Lake Sioux, 22, 204

American Indians, Standing Rock Sioux, 22, 204

American Indians, Yankton Sioux, 22, 204

Amphibians, 118, 168, 176, 184, 185, 270, 299,

300, 301, 302, 304, 305, 308, 346, 347, 389,

424, 425, 454, 455, 488, 489, 525, 526, 615,

620

Antelope Flats Road, 50, 54, 56, 59, 65, 74, 216,

277, 291, 311, 313, 316, 351, 352, 358, 375,

376, 390, 391, 393, 394, 398, 415, 416, 417,

428, 430, 433, 447, 453, 457, 458, 459, 461,

492, 493, 496, 529, 530, 533, 543

Archeological Resources Protection Act, 4

Archeology, 200, 621

Arctic grayling (Thymus arcticus), 185, 186

Avalanche hazards, 32, 64, 71, 152, 162, 163,

207, 269, 410, 420, 424, 474, 489, 517, 624

Backcountry use, 5, 28, 32, 47, 58, 62, 65, 67,

68, 69, 71, 151, 162, 163, 166, 178, 191, 213,

238, 249, 250, 269, 286, 287, 295, 296, 297,

303, 304, 306, 307, 308, 317, 331, 332, 337,

340, 343, 344, 345, 346, 347, 360, 362, 363,

366, 367, 374, 379, 382, 385, 387, 388, 389,

390, 399, 411, 416, 419, 421, 422, 423, 424,

425, 434, 435, 443, 444, 447, 448, 449, 450,

451, 452, 453, 454, 455, 463, 464, 474, 475,

480, 483, 485, 487, 488, 489, 499, 500, 501,

513, 517, 519, 520, 522, 523, 524, 525, 526,

534, 536, 537, 538, 539, 547, 548, 550, 555,

559, 564, 583, 587, 589, 593, 594, 595, 598,

600, 627

Bear Management Area, 68, 291, 296, 297, 341,

390

Bear, grizzly (Ursus arctos horribilis), 49, 52,

66, 68, 74, 170, 173, 174, 176, 177, 178, 263,

287, 289, 290, 291, 292, 293, 295, 296, 297,

307, 340, 341, 345, 346, 383, 387, 388, 390,

423, 424, 453, 454, 482, 483, 487, 488, 520,

524, 525, 526, 547, 548, 549, 574, 583, 591,

599, 615, 618, 619, 620, 621, 622, 627, 630

Beaverhead-Deerlodge National Forest, vi, 12,

543, 547, 550, 552, 553, 554, 557, 560, 562,

563

Bighorn sheep (Ovis canadensis), 47, 68, 69, 71,

79, 120, 169, 175, 176, 208, 252, 282, 283,

285, 286, 306, 307, 337, 345, 379, 387, 390,

416, 423, 425, 448, 453, 480, 517, 524, 526,

589, 598, 600, 613, 621, 632

Biodiversity Legal Foundation, iv, 1

Birds, 117, 118, 140, 167, 168, 173, 180, 184,

189, 616, 622

Bison (Bison bison), ix, xxviii, 9, 16, 17, 22, 23,

28, 30, 32, 33, 35, 36, 67, 68, 69, 70, 71, 74,

119, 134, 135, 137, 140, 141, 154, 156, 157,

160, 169, 170, 171, 172, 173, 174, 177, 208,

209, 210, 228, 231, 252, 279, 280, 281, 282,

283, 285, 286, 287, 297, 309, 319, 324, 335,

337, 341, 344, 347, 378, 379, 380, 383, 386,

390, 414, 415, 416, 422, 425, 447, 448, 455,

478, 479, 481, 486, 489, 515, 516, 517, 526,

559, 568, 569, 572, 574, 597, 598, 599, 612,

613, 614, 615, 620, 622, 623, 624

Black bear (Ursus americanus), 117

Blacktail Plateau, 49, 58, 208, 215, 285, 337,

340

Blue Ribbon Coalition, xi, 77

Bobcat (Felis rufus), 117

Bridger-Teton National Forest, vi, 12, 176, 211,

272, 541, 547, 549, 550, 553, 555, 558, 559,

560, 563, 566, 586, 587, 594, 598

Brucellosis, 17, 169, 172, 173, 613, 614, 623

Buffalo Fork River, 48, 180, 186

Bull snake (Pituophis melanoleucus), 118

Bunsen Peak, 58

Canyon, xxvii, 36, 47, 49, 50, 51, 52, 53, 54, 55,

56, 58, 59, 62, 64, 71, 73, 76, 78, 151, 163,

164, 178, 192, 200, 202, 208, 209, 210, 211,

212, 213, 215, 216, 221, 222, 275, 276, 277,

280, 289, 297, 311, 313, 314, 316, 332, 333,

337, 340, 344, 348, 349, 350, 351, 357, 362,

366, 368, 373, 375, 379, 383, 386, 390, 391,

392, 393, 394, 395, 397, 400, 401, 412, 413,

428, 429, 432, 444, 456, 459, 461, 475, 477,

481, 483, 486, 489, 491, 493, 494, 495, 513,

517, 528, 529, 532, 538, 555, 572, 574, 584,

617

Caribou-Targhee National Forest, 541, 548, 551,

553, 555, 558, 560, 564

Carrying capacity, ix, xvi, 9, 33, 74
INDEX

514

Case Incident Reports, 152, 158, 632

Chittenden Loop, 58

Chub, leatherside (Gila copei), 185, 186

Clean Air Act, 4, 143

Clean Water Act, 4

Climate, ix, 13, 278, 625, 626

Cody, xi, 13, 14, 47, 61, 206, 209, 215, 220, 405,

468, 544

Colter Bay, i, xiv, xvi, xxvii, 48, 50, 51, 54, 56,

58, 59, 61, 62, 64, 65, 73, 160, 166, 168, 194,

200, 211, 212, 214, 215, 216, 222, 242, 245,

262, 265, 266, 267, 268, 275, 276, 277, 311,

313, 315, 316, 327, 328, 329, 333, 350, 352,

357, 365, 370, 371, 372, 375, 376, 392, 394,

397, 400, 404, 405, 406, 407, 408, 409, 410,

411, 412, 413, 426, 427, 428, 430, 431, 432,

433, 438, 440, 441, 442, 444, 445, 457, 458,

459, 461, 470, 471, 472, 473, 475, 477, 491,

492, 493, 496, 509, 510, 511, 512, 514, 516,

519, 522, 524, 525, 527, 528, 530, 531, 532,

533, 535, 537, 538, 539, 543, 555, 577, 578,

579, 583, 626

Columbia River, 13

Commercial Services Plan, 35, 78, 593, 600

Continental Divide Snowmobile Trail, xiii, xiv,

17, 27, 32, 49, 50, 51, 53, 54, 56, 58, 59, 61,

62, 63, 67, 68, 69, 76, 77, 78, 161, 191, 194,

211, 222, 223, 268, 269, 281, 284, 309, 319,

322, 330, 335, 338, 339, 342, 343, 344, 345,

346, 347, 365, 373, 376, 378, 380, 384, 386,

395, 403, 404, 411, 414, 417, 431, 438, 439,

447, 460, 462, 466, 489, 495, 497, 512, 515,

516, 518, 521, 538, 543, 544, 545, 552, 557,

558, 559, 563, 566, 567, 571, 572, 576, 577,

578, 579, 583, 587, 632

cooperating agencies, ix, xi, xiii, xvi, xxv, xxvii,

11, 17, 18, 19, 20, 23, 30, 34, 35, 38, 51, 60,

65, 75, 121, 172, 233, 238, 240, 241, 257, 505,

539, 540, 542, 580, 581, 582, 583, 603, 607,

610, 614

Council on Environmental Quality, viii, ix, xi,

xiii, 6, 8, 9, 11, 20, 48, 53, 60, 64, 80, 115,

141, 142, 234, 235, 257, 540, 542, 581, 585,

603, 615

Coyote (Canis latrans), 117, 189, 191, 288, 618,

623

Cross-country skiing, xxviii, 5, 13, 31, 129, 137,

139, 141, 190, 195, 207, 208, 213, 214, 215,

216, 218, 220, 225, 227, 228, 230, 239, 285,

286, 294, 416, 417, 431, 506, 508, 547, 553,

590, 613, 614

Cultural resources, 24, 30, 66, 116, 200, 205,

256, 257, 263, 314, 352, 354, 395, 431, 460,

494, 531, 590, 601, 607, 609

Cumulative impacts, viii, xxvi, 8, 27, 234, 546,

581, 584, 585, 592, 593, 595, 597, 598, 599,

601, 603

Cunningham Cabin, 53, 59, 202, 613

Custer National Forest, vi, 12, 548, 551, 554,

556, 559, 560, 561, 564, 570

Death Canyon, 50, 54, 56, 59, 216

Deer, mule (Odocoileus hemionus), 154, 171,

208, 209, 280, 282, 283, 287, 337, 379, 383,

447, 481, 517, 616, 619, 620, 621, 623, 626,

627

Ditch Creek, 48, 53, 291

Dubois, 13, 17, 206, 211, 398, 495, 547

Dunraven Pass, 162

Eagle, bald (Haliaetus leucephalus), 66, 118,

165, 167, 173, 174, 176, 179, 180, 252, 263,

287, 289, 292, 293, 294, 296, 297, 300, 307,

345, 346, 388, 417, 418, 423, 424, 453, 454,

487, 488, 524, 525, 550, 552, 563, 583, 599,

611, 618, 619, 622, 623, 628, 629, 631

Ecology Center, iv, 1

Economic effects, viii, x, xii, xiii, xxviii, xxxi, 3,

8, 12, 18, 20, 28, 32, 34, 39, 121, 123, 125,

126, 127, 130, 141, 142, 172, 205, 228, 233,

234, 237, 240, 263, 321, 323, 325, 326, 368,

404, 405, 406, 467, 468, 469, 502, 503, 504,

505, 507, 508, 539, 540, 542, 543, 544, 545,

558, 569, 570, 571, 572, 573, 576, 577, 578,

579, 580, 583, 590, 591, 597, 605, 606, 608,

622, 626, 627, 629, 630, 632

Elk (Cervus canadensis), vi, 12, 71, 169, 171,

173, 174, 175, 206, 210, 233, 280, 283, 285,

380, 490, 517, 566, 612, 614, 617, 621, 625,

628, 632

Emissions, xxviii, xxix, xxx, xxxi, 28, 32, 51, 57,

70, 75, 142, 143, 144, 145, 146, 147, 242, 243,

244, 245, 246, 249, 265, 266, 267, 270, 271,

272, 273, 274, 275, 276, 277, 278, 299, 300,

326, 327, 328, 332, 333, 334, 341, 369, 370,

371, 374, 375, 376, 384, 407, 408, 410, 412,

413, 420, 440, 441, 442, 444, 445, 450, 470,

471, 473, 476, 477, 484, 509, 510, 512, 514,

521, 568, 589, 595, 611, 612, 613, 615, 616,

617, 619, 620, 621, 623, 624, 625, 626, 628,

630, 631, 632

Emma Matilda Lake, 164

Endangered Species Act, iv, 1, 4, 24, 25, 118,

119, 176, 177, 178, 179, 181, 184, 186, 251,

609, 629

Entrance, East, xiv, xxix, 49, 52, 55, 56, 58, 64,

73, 78, 129, 162, 193, 206, 207, 208, 209, 215,

218, 220, 238, 239, 269, 275, 276, 277, 311,

313, 314, 316, 332, 333, 349, 350, 352, 357,

375, 376, 392, 394, 397, 404, 405, 406, 410,

412, 413, 414, 415, 417, 420, 422, 424, 426,

428, 429, 430, 431, 432, 433, 434, 435, 445,

456, 457, 458, 459, 460, 461, 469, 475, 477,

491, 492, 493, 495, 496, 497, 502, 513, 514,

528, 529, 530, 532, 533, 543, 544, 552, 555,

556, 557, 558, 560, 561, 562, 566, 569, 570,

571, 582, 586
515

Entrance, North, xxix, 13, 55, 63, 203, 205, 208,

218, 219, 221, 228, 238, 241, 284, 314, 362,

400, 495, 500, 501, 502, 543, 544, 545, 562,

587

Entrance, Northeast, 47, 73, 202, 205, 207, 209,

218, 242, 262, 266, 276, 310, 311, 313, 314,

316, 348, 350, 351, 357, 391, 392, 393, 397,

426, 428, 429, 456, 457, 491, 495, 527, 528,

529, 532

Entrance, South, xxix, 49, 52, 55, 73, 156, 161,

207, 210, 211, 218, 221, 262, 277, 309, 311,

313, 314, 315, 316, 320, 348, 349, 350, 352,

355, 357, 359, 367, 381, 386, 391, 392, 393,

394, 396, 398, 400, 405, 406, 426, 428, 429,

430, 431, 433, 439, 457, 458, 459, 461, 474,

490, 492, 493, 496, 500, 502, 507, 527, 528,

529, 530, 532, 535, 544, 545, 552, 558, 560,

576, 577, 578, 579

Entrance, West, xv, xxviii, xxix, 52, 55, 61, 63,

64, 68, 69, 70, 72, 73, 78, 127, 128, 129, 144,

147, 149, 156, 206, 207, 210, 218, 219, 220,

228, 241, 242, 243, 245, 246, 265, 266, 267,

268, 276, 277, 281, 289, 310, 311, 313, 314,

316, 319, 320, 321, 322, 326, 327, 328, 329,

330, 331, 333, 336, 342, 348, 349, 350, 351,

354, 355, 357, 359, 360, 361, 362, 363, 367,

369, 370, 371, 372, 375, 377, 378, 381, 385,

390, 391, 392, 393, 395, 397, 398, 399, 400,

401, 407, 408, 409, 410, 412, 426, 428, 429,

432, 435, 436, 440, 441, 442, 444, 456, 457,

458, 459, 461, 470, 471, 472, 473, 475, 477,

478, 482, 484, 490, 491, 492, 493, 494, 495,

499, 500, 503, 504, 509, 510, 511, 512, 513,

527, 528, 529, 532, 543, 545, 551, 552, 557,

561, 562, 566, 575, 582, 586, 623, 624, 625

Environmental Impact Statement, i, ii, iv, vi, vii,

viii, ix, x, xi, xii, xiii, xvi, xxv, 1, 2, 4, 6, 7, 8,

9, 10, 11, 12, 17, 19, 20, 22, 23, 24, 25, 30, 33,

34, 35, 36, 38, 46, 48, 51, 60, 65, 76, 115, 116,

117, 120, 121, 141, 142, 172, 178, 191, 204,

214, 232, 234, 237, 251, 270, 324, 507, 508,

539, 542, 555, 567, 569, 572, 581, 583, 585,

589, 597, 598, 599, 606, 608, 610, 616, 624,

630

Environmental Protection Agency, iv, xvi, 1, 38,

47, 63, 65, 67, 78, 141, 143, 144, 146, 147,

149, 235, 241, 242, 243, 244, 246, 247, 271,

272, 273, 597, 613, 616, 617, 630

Ethnographic resources, 203, 205, 353, 608

Exotic species, 119, 120

Facilities, vi, vii, viii, ix, xiv, xxix, 2, 7, 8, 9, 14,

16, 19, 27, 28, 31, 33, 36, 39, 47, 50, 53, 54,

55, 56, 57, 59, 61, 62, 65, 66, 75, 76, 78, 115,

141, 151, 167, 201, 207, 213, 214, 215, 216,

218, 227, 250, 262, 287, 297, 305, 306, 307,

308, 314, 317, 334, 337, 340, 341, 343, 344,

345, 346, 347, 352, 353, 367, 377, 379, 382,

383, 386, 387, 388, 389, 403, 404, 412, 414,

417, 419, 421, 423, 424, 425, 431, 438, 446,

448, 450, 452, 453, 454, 455, 478, 481, 483,

485, 486, 487, 488, 489, 515, 517, 520, 523,

524, 525, 526, 548, 557, 564, 580, 582, 583,

584, 585, 594, 595, 599, 601

Falcon, peregrine (Falco peregrinus), 118

Federal Clean Air Act, 4, 143

Firehole River, 280, 289, 611, 613, 620

Fisher (Martes pennanti), 117, 182, 183, 298,

300, 304, 600, 611, 615, 620, 627

Fisheries, 126, 165, 611, 620, 631

Fishing Bridge, 49, 52, 55, 58, 62, 73, 193, 202,

209, 215, 222, 275, 276, 277, 289, 310, 311,

313, 314, 316, 332, 333, 348, 349, 350, 351,

352, 357, 368, 375, 390, 391, 392, 393, 394,

395, 397, 400, 401, 412, 413, 415, 422, 426,

428, 429, 430, 431, 432, 434, 444, 445, 456,

457, 459, 461, 475, 477, 491, 493, 494, 495,

496, 513, 514, 528, 529, 530, 532

Flagg Ranch, i, xiii, xiv, xv, xvi, xxvii, 48, 50,

51, 53, 54, 56, 57, 58, 59, 60, 61, 62, 64, 65,

69, 73, 126, 147, 160, 161, 190, 191, 192, 193,

194, 200, 203, 206, 207, 210, 211, 212, 213,

214, 215, 216, 222, 242, 245, 246, 262, 265,

266, 267, 268, 276, 277, 284, 294, 310, 311,

313, 315, 316, 320, 322, 327, 328, 329, 330,

332, 333, 335, 338, 342, 348, 349, 350, 352,

355, 357, 365, 367, 369, 370, 371, 372, 373,

375, 390, 391, 392, 393, 394, 396, 397, 407,

408, 409, 410, 411, 412, 413, 417, 426, 427,

428, 430, 431, 432, 433, 439, 440, 441, 442,

443, 444, 445, 446, 448, 450, 456, 457, 458,

459, 460, 461, 462, 466, 468, 470, 471, 472,

473, 474, 475, 477, 490, 491, 492, 493, 494,

495, 496, 497, 502, 509, 510, 511, 512, 514,

516, 519, 522, 525, 527, 528, 530, 531, 532,

533, 538, 539, 543, 544, 545, 554, 555, 557,

558, 559, 561, 570, 571, 576, 577, 578, 579,

580, 583, 587, 625, 628

Floodplains, 68, 116, 334, 606

Fountain Flats (Freight Road), 35, 36, 55, 58, 64,

210, 280, 374, 411, 412, 513

Fox, red (Vulpes vulpes), 117

Frog, spotted (Rana pretiosa), 176

Frog, western chorus (Pseudacris triseriata), 176

Gallatin County, 19, 579

Gallatin National Forest, i, vi, ix, 12, 19, 121,

163, 164, 174, 205, 238, 543, 549, 551, 552,

554, 556, 559, 560, 561, 562, 565, 567, 572,

574, 575, 579, 584, 614

Gardiner, 13, 47, 123, 154, 157, 205, 208, 233,

241, 285, 358, 468, 469, 496, 545, 560, 561,

586

Garter snake (Thamnophis sirtalis), 176

General Authorities Act, 2, 3, 607, 608

Geology, 270

Geothermal resources, i, xiv, 28, 51, 56, 116,

164, 235, 249, 269, 279, 285, 299, 300, 301,
INDEX

516

304, 305, 331, 332, 336, 373, 374, 379, 411,

412, 416, 443, 444, 447, 474, 475, 480, 513,

516, 589, 593, 628

Gibbon River, 165, 170, 208, 210, 211, 278, 279,

289, 291, 595, 615

Grand Teton National Park, i, iv, vi, x, xii, xxvii,

xxviii, xxix, xxx, xxxi, 1, 2, 4, 5, 12, 13, 16,

17, 21, 33, 35, 36, 38, 48, 50, 51, 54, 57, 58,

60, 61, 62, 63, 67, 68, 69, 71, 77, 79, 103, 105,

107, 109, 111, 113, 116, 120, 121, 126, 129,

130, 131, 139, 142, 143, 146, 147, 158, 159,

160, 161, 163, 164, 165, 166, 167, 168, 169,

170, 173, 174, 175, 176, 178, 179, 180, 181,

182, 183, 185, 189, 190, 191, 194, 195, 201,

202, 203, 204, 206, 211, 213, 214, 215, 216,

221, 222, 223, 224, 225, 226, 228, 230, 233,

237, 238, 239, 240, 241, 245, 247, 251, 253,

258, 259, 262, 264, 269, 271, 275, 278, 279,

280, 282, 284, 285, 286, 287, 289, 291, 292,

294, 295, 296, 298, 299, 300, 301, 302, 303,

306, 307, 308, 309, 310, 315, 317, 319, 320,

321, 322, 330, 331, 334, 335, 336, 337, 338,

339, 340, 341, 342, 343, 344, 345, 346, 347,

348, 349, 355, 359, 364, 365, 367, 368, 373,

376, 377, 378, 379, 380, 381, 382, 383, 384,

385, 386, 387, 388, 389, 390, 391, 393, 395,

398, 400, 403, 404, 411, 413, 414, 415, 416,

417, 418, 419, 420, 421, 422, 423, 424, 425,

426, 429, 430, 431, 434, 436, 439, 443, 445,

446, 447, 448, 449, 450, 451, 452, 453, 454,

455, 456, 457, 458, 460, 462, 465, 466, 467,

468, 474, 476, 478, 479, 480, 481, 482, 483,

484, 485, 486, 487, 488, 489, 490, 491, 492,

494, 495, 497, 501, 502, 506, 508, 512, 514,

515, 516, 517, 518, 519, 521, 522, 523, 524,

525, 526, 527, 529, 530, 531, 534, 537, 538,

540, 543, 544, 545, 548, 553, 555, 557, 558,

559, 566, 567, 568, 569, 571, 572, 577, 578,

587, 588, 589, 593, 594, 595, 597, 598, 600,

612, 613, 616, 619, 620, 621, 623, 624, 625,

626, 627, 628, 631, 632

Granite Canyon, 49, 50, 53, 54, 56, 59, 212, 216

Grant Village, 76, 315

Grassy Lake Road, xiv, xv, 50, 53, 56, 59, 60,

61, 64, 71, 72, 73, 78, 194, 211, 275, 276, 311,

313, 316, 319, 333, 335, 342, 350, 352, 357,

365, 375, 392, 394, 397, 413, 417, 428, 430,

431, 433, 438, 439, 443, 445, 446, 448, 450,

456, 457, 459, 460, 461, 466, 477, 490, 492,

493, 496, 502, 514, 527, 528, 530, 532, 533,

544, 545, 558, 570, 571, 581

Greater Yellowstone Area, iv, vi, x, xxvii, xxviii,

1, 2, 12, 13, 14, 17, 21, 25, 30, 31, 35, 48, 74,

117, 120, 121, 123, 124, 125, 126, 127, 128,

129, 130, 131, 133, 137, 139, 140, 141, 146,

151, 164, 166, 168, 171, 173, 177, 178, 179,

180, 184, 200, 201, 204, 205, 230, 232, 233,

237, 238, 239, 240, 241, 242, 257, 263, 264,

265, 270, 288, 294, 321, 322, 323, 324, 325,

326, 368, 404, 405, 406, 467, 468, 469, 502,

503, 504, 505, 506, 508, 539, 541, 542, 543,

544, 545, 546, 547, 550, 551, 552, 553, 554,

557, 558, 559, 560, 561, 562, 563, 564, 565,

566, 567, 572, 573, 575, 576, 580, 581, 582,

583, 585, 586, 587, 588, 599, 600, 614, 616,

618, 619, 623

Greater Yellowstone Coordinating Committee,

iv, vii, 1, 7, 17, 166, 232, 241, 242, 540, 546,

547, 548, 549, 550, 582, 614, 618, 619

Gros Ventre Junction, 22, 48, 56, 167, 169, 174,

175, 176, 178, 179, 204, 212, 213, 223, 224,

233, 252, 377, 379, 380, 382, 384, 563

Gull Point Drive, 52, 55, 58

Hayden Valley, 172, 173, 209, 279, 620

Hebgen Lake District, 549, 556, 573, 574

Highway 89/287, 252, 334, 376, 414

Historic preservation, 4, 24, 116, 203, 256, 353

Hoyt, 162

Idaho, i, vi, ix, x, xi, xiii, 12, 13, 19, 21, 24, 25,

38, 119, 121, 126, 130, 131, 133, 137, 139,

144, 145, 151, 157, 164, 178, 182, 183, 184,

205, 206, 215, 225, 227, 232, 238, 256, 258,

259, 263, 271, 323, 405, 504, 533, 538, 539,

540, 548, 551, 554, 571, 573, 575, 576, 580,

581, 582, 583, 584, 611, 615, 619, 620, 621,

623, 625, 626, 630, 631, 632

Idaho State Snowmobile Association, 151, 269

IMPLAN input/output model, 127, 237, 240,

321, 405, 468, 503

Indian Creek, 49, 52, 55, 58, 208, 215

Interagency Bison Management Plan, 22, 36,

624

Island Park, 13, 551, 553, 556, 564, 584

Jackson, i, xi, xiii, xiv, xv, xvi, 5, 13, 14, 35, 47,

48, 49, 50, 53, 56, 57, 59, 61, 62, 63, 65, 69,

72, 77, 78, 130, 163, 164, 165, 166, 167, 168,

169, 173, 174, 175, 176, 178, 179, 180, 186,

190, 194, 203, 206, 210, 211, 212, 214, 216,

222, 226, 233, 241, 244, 246, 252, 254, 255,

262, 277, 278, 289, 309, 310, 312, 313, 318,

320, 322, 330, 331, 334, 348, 349, 351, 352,

355, 365, 366, 367, 374, 376, 378, 380, 390,

391, 393, 394, 395, 398, 411, 414, 418, 426,

427, 429, 430, 431, 433, 438, 443, 446, 456,

457, 458, 460, 466, 468, 476, 490, 491, 492,

493, 494, 495, 497, 512, 515, 526, 527, 529,

530, 534, 538, 539, 551, 553, 554, 555, 560,

566, 568, 569, 576, 577, 578, 579, 586, 587,

598, 612, 614, 615, 622, 626, 627

Jackson Hole, 35, 49, 77, 163, 169, 174, 178,

186, 190, 211, 233, 244, 246, 262, 553, 554,

598

Jackson Lake, i, xiii, xiv, xv, xvi, 5, 13, 48, 49,

50, 53, 56, 57, 59, 61, 62, 63, 65, 72, 78, 164,

165, 166, 167, 168, 176, 180, 190, 194, 203,

212, 214, 216, 222, 252, 254, 255, 277, 278,
517

289, 309, 310, 312, 313, 318, 320, 330, 331,

334, 348, 349, 351, 352, 355, 365, 366, 367,

374, 376, 378, 391, 393, 394, 411, 414, 418,

426, 427, 429, 430, 431, 438, 443, 446, 456,

457, 458, 460, 466, 476, 490, 491, 492, 493,

494, 512, 515, 526, 527, 529, 530, 534, 538,

539, 566, 568, 578, 579, 586, 587, 626

Jenny Lake, 50, 54, 56, 59, 202, 203, 212, 216,

222, 315, 355, 417, 419, 421, 422, 424, 432

John D. Rockefeller, Jr. Memorial Parkway, i, ii,

iv, vi, x, xii, xiv, xv, xxvii, xxviii, xxix, 1, 2,

4, 12, 13, 16, 17, 33, 36, 38, 48, 49, 50, 53, 54,

56, 57, 58, 59, 60, 61, 62, 64, 67, 68, 73, 103,

105, 107, 109, 111, 113, 121, 143, 158, 159,

160, 161, 163, 164, 174, 175, 178, 180, 182,

190, 191, 193, 203, 204, 206, 210, 211, 213,

214, 215, 222, 223, 224, 225, 226, 230, 233,

238, 247, 251, 258, 275, 279, 280, 282, 284,

285, 287, 289, 292, 294, 298, 299, 301, 303,

310, 315, 317, 320, 322, 335, 336, 338, 339,

341, 342, 343, 355, 359, 364, 368, 376, 377,

378, 379, 380, 381, 382, 384, 385, 395, 398,

403, 411, 414, 415, 416, 417, 418, 419, 420,

421, 431, 433, 434, 436, 439, 443, 452, 460,

462, 465, 467, 468, 478, 495, 497, 501, 508,

517, 518, 519, 521, 522, 531, 533, 537, 538,

543, 544, 545, 558, 567, 593, 612, 616, 619,

625

Kelly, 48, 120, 176, 179, 212, 213, 252, 286

Kelly Hill, 48, 176, 252

Lake Butte Drive, 52, 55

Lake trout (Salvelinus namaycush), 186

Lake Village, 315

Lone Star Geyser Basin, 210, 374, 443, 513

Low-income populations, 130, 237, 264, 323,

326, 368, 369, 406, 439, 469, 505, 507

Lynx (Lynx canadensis), 66, 67, 68, 69, 70, 71,

72, 74, 117, 176, 181, 182, 263, 287, 292, 293,

294, 295, 297, 298, 306, 307, 309, 338, 339,

345, 346, 347, 380, 381, 382, 383, 386, 388,

390, 423, 424, 425, 453, 454, 455, 487, 488,

489, 518, 519, 524, 525, 526, 548, 550, 551,

552, 553, 554, 563, 583, 585, 599, 600, 611,

613, 615, 619, 620, 621, 623, 627, 629, 630,

631

Madison Junction, 210, 211, 214, 245, 268,

281, 289, 321, 360, 362, 368, 397, 399, 400,

435, 478, 482, 484, 499

Madison River, 211, 280, 289, 484, 595, 597

Mailbox Corner, 48, 53, 212, 213

Mammoth Hot Springs, 13, 16, 135, 157, 207,

208, 213, 214, 215, 218, 222, 245, 285, 337,

340, 379, 382, 416

Marten (Martes americana), 117, 182, 184, 298,

299, 301, 302, 308, 341, 344, 346, 384, 386,

389, 420, 422, 424, 451, 454, 484, 486, 488,

521, 525, 611, 620, 627, 629

Mesa Road, 58

Mississippi River, 13

Missouri River, 13

Montana, i, vi, ix, x, xi, 12, 13, 19, 20, 21, 23,

24, 25, 35, 36, 47, 69, 70, 71, 77, 78, 119, 121,

123, 126, 127, 130, 131, 133, 137, 139, 144,

145, 147, 154, 172, 182, 183, 184, 205, 206,

207, 208, 209, 225, 227, 229, 232, 238, 241,

256, 258, 259, 263, 266, 271, 282, 285, 289,

292, 301, 321, 323, 405, 468, 469, 504, 506,

539, 540, 567, 571, 572, 573, 574, 575, 579,

580, 582, 583, 584, 597, 611, 612, 613, 614,

615, 617, 619, 621, 623, 624, 625, 626, 628,

629, 630, 632

Moose (Alces alces), 48, 49, 50, 51, 53, 54, 56,

58, 59, 61, 65, 71, 73, 78, 126, 129, 169, 175,

195, 202, 211, 212, 216, 222, 223, 224, 238,

239, 251, 252, 262, 277, 284, 311, 313, 315,

316, 333, 350, 352, 357, 375, 376, 378, 381,

385, 392, 394, 395, 398, 412, 413, 417, 428,

430, 433, 444, 445, 447, 457, 459, 461, 475,

478, 490, 492, 493, 496, 514, 517, 528, 530,

533, 543, 613

Moose Junction, 48, 211, 212, 216, 252, 417

Moose-Wilson Road, 49, 53, 56, 61, 65, 73, 78,

212, 223, 277, 311, 313, 315, 316, 333, 350,

352, 357, 375, 376, 378, 381, 385, 392, 394,

395, 398, 412, 413, 417, 428, 430, 433, 444,

445, 457, 459, 461, 475, 478, 492, 493, 496,

514, 528, 530, 533, 543

Moran, xiii, 48, 50, 53, 56, 59, 69, 73, 126, 129,

158, 160, 164, 178, 179, 194, 202, 206, 211,

223, 224, 233, 238, 239, 251, 252, 262, 275,

276, 277, 284, 294, 309, 310, 311, 313, 315,

316, 320, 322, 330, 333, 335, 338, 342, 348,

349, 350, 352, 357, 373, 376, 377, 378, 380,

384, 386, 390, 391, 392, 393, 394, 395, 397,

398, 413, 426, 428, 429, 430, 433, 444, 445,

457, 458, 459, 461, 475, 477, 490, 491, 492,

493, 496, 514, 527, 528, 529, 530, 532, 538,

553, 558, 560, 577

Mountain goat (Oreamnos americanus), 120,

620, 631

National Ambient Air Quality Standards, 4, 28,

69, 143, 144

National Atmospheric Deposition Program, 146

National Elk Refuge, vi, 12, 169, 173, 174, 175,

179, 206, 233, 566

National Environmental Policy Act, iv, 1, 10, 20,

30, 34, 38, 53, 60, 64, 141, 142, 235, 237, 257,

585, 586, 603, 606, 607, 608, 609, 610, 615,

628

National Historic Landmarks, xxviii, 201, 202

National Historic Preservation Act, 4, 24

National Register of Historic Places, xxviii, 116,

201, 202, 203, 205, 256, 353, 609

Natural Bridge, 52, 55, 58

Natural Regulation Alternative, xi, 76, 77
INDEX

518

Noise effects, i, vii, viii, x, xiii, xiv, xv, xxvii,

xxviii, 7, 8, 9, 28, 31, 32, 47, 50, 51, 52, 54,

57, 59, 60, 61, 63, 64, 65, 78, 187, 188, 189,

190, 191, 192, 193, 194, 199, 200, 226, 252,

253, 254, 255, 256, 259, 260, 280, 309, 310,

320, 348, 349, 362, 363, 367, 391, 393, 427,

429, 436, 439, 458, 464, 465, 492, 500, 502,

505, 509, 523, 527, 529, 536, 547, 591, 600,

601, 603, 610, 617

Noise, aircraft, 190, 191, 290, 601

Nonmarket values, 140, 141, 237, 264, 325, 368,

406, 439, 469, 506

Norris, 35, 36, 49, 52, 53, 55, 62, 73, 201, 202,

208, 211, 214, 215, 221, 222, 269, 275, 276,

277, 287, 289, 291, 297, 298, 305, 307, 311,

313, 315, 316, 332, 333, 337, 340, 344, 350,

351, 357, 358, 359, 368, 373, 374, 375, 379,

383, 386, 392, 393, 395, 397, 399, 400, 401,

412, 428, 429, 432, 444, 456, 459, 461, 474,

475, 477, 481, 483, 486, 490, 491, 492, 493,

495, 499, 513, 517, 520, 523, 528, 529, 532,

571

Norris Geyser, 201, 208, 211, 269, 374, 474, 475

Northern sagebrush lizard (Sceloporus

graciosus), 185, 300, 301, 304, 305, 308, 347,

389, 425, 455, 489, 522, 526

Obsidian Cliff, 201, 202

Old Faithful, xiii, xiv, xxvii, xxviii, 16, 47, 49,

50, 52, 53, 54, 55, 58, 62, 64, 67, 68, 69, 72,

73, 76, 119, 131, 132, 133, 141, 147, 149, 151,

156, 192, 199, 201, 202, 207, 208, 210, 213,

214, 215, 221, 222, 227, 242, 245, 246, 255,

265, 266, 267, 268, 269, 274, 275, 276, 277,

280, 282, 289, 291, 297, 310, 311, 313, 315,

316, 319, 320, 321, 322, 323, 324, 325, 326,

327, 328, 329, 330, 331, 332, 333, 336, 339,

340, 342, 348, 349, 350, 351, 352, 354, 355,

356, 357, 358, 359, 360, 361, 362, 363, 368,

369, 370, 371, 372, 373, 374, 375, 377, 378,

379, 381, 382, 383, 385, 386, 390, 391, 392,

393, 394, 395, 396, 397, 398, 399, 400, 401,

407, 408, 409, 410, 411, 413, 426, 428, 430,

432, 433, 435, 436, 440, 441, 442, 445, 457,

458, 459, 461, 467, 470, 471, 472, 473, 475,

477, 478, 482, 484, 490, 491, 492, 493, 494,

496, 497, 499, 500, 501, 507, 509, 510, 511,

512, 514, 527, 528, 529, 530, 532, 533, 535,

541, 542, 544, 551, 569, 570, 571, 573, 575,

577, 578, 582, 590, 593, 597

Organic Act, 2, 3, 187, 608

Otter, river (Lutra canadensis), 182, 184, 299,

300, 301, 302, 303, 304, 305, 308, 346, 347,

389, 424, 425, 454, 455, 488, 489, 525, 526

Pelican Valley, xxvii, 36, 170, 172, 193, 200,

209, 414, 622

Pine, lodgepole (Pinus contorta), 175, 181, 184,

209

Pine, whitebark (Pinus albicaulis), 177, 178,

290, 296, 621, 622

Predator Project, iv, 1, 629

Public health, vii, xxix, 7, 116, 142, 143, 235,

236, 241, 246, 247, 264, 268, 326, 369, 407,

439, 470, 509, 609, 613

Public safety, viii, xxix, 8, 116, 151, 152, 235,

236, 247, 248, 268, 329, 330, 331, 372, 373,

410, 411, 443, 473, 474, 512

Purpose and need for action, vii, xii, xiii, xxv, 6,

7, 12, 30, 34, 35, 38, 76, 115, 116, 120, 235,

591, 592, 609

Rattlesnake, prairie (Crotalis viridis viridis), 118

Red Rocks National Wildlife Refuge, vi, 12

Redwood Act, 3

Resources, i, vi, vii, viii, ix, x, xii, xiii, xiv, xv,

xxvi, xxviii, xxix, 2, 3, 4, 5, 6, 7, 8, 9, 12, 13,

19, 20, 24, 27, 28, 29, 30, 32, 36, 39, 46, 50,

52, 53, 54, 56, 57, 58, 59, 60, 61, 63, 64, 66,

68, 69, 74, 75, 76, 78, 79, 115, 116, 124, 125,

140, 141, 142, 146, 163, 164, 165, 168, 187,

200, 201, 202, 203, 204, 205, 227, 234, 235,

236, 249, 250, 256, 257, 262, 263, 269, 270,

272, 275, 278, 300, 301, 305, 306, 314, 331,

332, 334, 342, 344, 352, 353, 354, 363, 374,

376, 384, 387, 395, 411, 412, 413, 414, 420,

422, 431, 434, 439, 443, 444, 445, 446, 451,

452, 460, 462, 465, 474, 475, 476, 478, 484,

486, 494, 497, 513, 514, 515, 521, 523, 531,

537, 539, 546, 568, 572, 582, 584, 589, 590,

591, 592, 593, 594, 595, 596, 601, 605, 606,

607, 608, 609, 613, 618, 619, 620, 622, 623,

624, 625, 626, 627, 628, 629, 631

Revised Alternative E, xi, xxviii, 11, 67, 77, 78

Riverside Drive, 52, 55, 58

Roads, plowed and groomed, i, 5, 14, 16, 27, 35,

47, 53, 60, 62, 63, 64, 66, 67, 69, 71, 77, 119,

131, 132, 133, 134, 135, 137, 162, 163, 167,

171, 172, 173, 190, 193, 202, 204, 205, 207,

211, 225, 226, 231, 249, 250, 252, 262, 269,

277, 279, 280, 281, 282, 283, 285, 286, 287,

289, 291, 292, 293, 295, 296, 297, 298, 299,

301, 302, 306, 307, 308, 319, 324, 332, 334,

335, 336, 337, 338, 339, 341, 342, 344, 345,

346, 347, 352, 353, 361, 365, 368, 373, 374,

376, 377, 378, 380, 381, 382, 383, 384, 385,

387, 388, 389, 398, 399, 401, 403, 412, 413,

414, 415, 416, 417, 418, 419, 420, 421, 422,

423, 424, 425, 443, 445, 446, 447, 448, 449,

450, 451, 453, 454, 455, 464, 467, 468, 469,

470, 474, 475, 476, 478, 479, 480, 481, 482,

483, 484, 485, 486, 487, 488, 489, 500, 513,

514, 515, 516, 518, 519, 520, 521, 522, 523,

524, 525, 542, 543, 544, 545, 554, 558, 564,

574, 594, 595, 596, 597, 601, 612, 630

Ross’ bentgrass (Agrostis rossiae), 119

Salamander, blotch tiger (Ambystoma tigrinum),

176
519

Section 106, 24

Shoshone National Forest, vi, 12, 21, 24, 170,

174, 200, 204, 207, 211, 232, 272, 549, 552,

554, 556, 558, 559, 560, 562, 566, 570, 586,

587

Snake River, 13

Snake River cutthroat trout (Oncorhynchus

clarki), 185, 186

Snowcoach, i, viii, xvi, 8, 13, 27, 62, 63, 64, 65,

70, 76, 77, 129, 131, 132, 133, 152, 154, 156,

159, 160, 161, 190, 193, 207, 215, 216, 217,

219, 220, 221, 226, 228, 231, 244, 246, 254,

255, 261, 267, 268, 276, 282, 300, 314, 317,

319, 323, 324, 328, 329, 333, 348, 354, 355,

356, 358, 360, 361, 363, 365, 368, 371, 372,

375, 390, 395, 396, 397, 399, 400, 401, 403,

408, 410, 412, 426, 429, 432, 433, 434, 436,

441, 442, 444, 460, 462, 465, 471, 473, 477,

486, 495, 499, 501, 502, 503, 504, 505, 506,

507, 508, 510, 511, 512, 514, 516, 531, 533,

534, 535, 536, 537, 538, 539, 542, 545, 555,

578, 580, 581, 590

Snowmobiles, i, viii, x, xiii, xiv, xv, xvi, xxviii,

2, 3, 5, 6, 8, 13, 14, 16, 17, 19, 27, 28, 29, 31,

32, 33, 46, 48, 49, 50, 51, 53, 54, 56, 57, 59,

60, 61, 62, 63, 64, 65, 67, 68, 69, 70, 71, 72,

73, 74, 76, 77, 78, 118, 119, 126, 131, 132,

133, 139, 141, 142, 143, 147, 149, 151, 152,

153, 154, 156, 157, 158, 159, 160, 161, 162,

166, 187, 189, 190, 191, 192, 193, 194, 195,

207, 212, 214, 215, 216, 217, 219, 220, 221,

222, 223, 224, 225, 226, 227, 230, 231, 232,

241, 242, 243, 244, 246, 249, 254, 255, 256,

257, 260, 261, 262, 265, 266, 267, 268, 269,

270, 271, 272, 273, 274, 275, 276, 277, 278,

280, 281, 282, 284, 286, 287, 289, 290, 291,

299, 300, 306, 308, 309, 310, 311, 313, 314,

316, 319, 320, 322, 323, 324, 325, 326, 328,

329, 330, 331, 332, 333, 334, 338, 342, 344,

347, 348, 349, 351, 352, 354, 355, 356, 357,

358, 361, 362, 363, 366, 367, 368, 369, 371,

372, 373, 374, 375, 376, 380, 384, 386, 390,

391, 393, 394, 395, 396, 397, 398, 399, 401,

403, 404, 405, 408, 410, 411, 412, 414, 415,

416, 417, 418, 420, 426, 428, 429, 430, 431,

432, 433, 435, 436, 438, 439, 441, 442, 443,

444, 451, 456, 457, 459, 460, 461, 464, 465,

466, 467, 471, 473, 474, 475, 477, 479, 481,

484, 486, 489, 490, 491, 492, 493, 495, 496,

497, 500, 501, 502, 503, 504, 505, 506, 508,

509, 510, 511, 512, 513, 514, 515, 518, 521,

523, 524, 525, 527, 529, 530, 531, 532, 533,

535, 536, 537, 538, 539, 540, 541, 543, 544,

545, 546, 547, 548, 549, 550, 551, 552, 553,

554, 555, 556, 557, 558, 560, 561, 562, 563,

564, 566, 568, 569, 570, 571, 572, 573, 574,

575, 576, 577, 578, 579, 580, 581, 582, 583,

585, 586, 587, 588, 590, 594, 595, 596, 611,

612, 614, 616, 617, 618, 619, 620, 623, 624,

627, 628, 629, 631, 632

Snowmobiles and Snowcoaches, i, vii, xiv, xv,

xvi, xxviii, xxix, xxx, xxxi, 5, 7, 14, 16, 23,

32, 36, 46, 47, 48, 49, 50, 51, 52, 53, 54, 56,

57, 58, 59, 60, 61, 62, 63, 64, 66, 67, 70, 71,

72, 74, 76, 77, 119, 134, 135, 137, 151, 190,

191, 192, 193, 194, 206, 207, 208, 211, 212,

213, 215, 218, 225, 226, 231, 250, 252, 253,

254, 255, 257, 259, 260, 263, 271, 274, 275,

276, 277, 278, 280, 281, 282, 289, 291, 292,

294, 299, 300, 301, 303, 304, 305, 306, 307,

308, 309, 310, 313, 317, 318, 319, 324, 326,

334, 335, 338, 339, 341, 342, 343, 344, 345,

346, 347, 348, 349, 351, 354, 355, 358, 359,

361, 362, 363, 365, 376, 377, 380, 384, 386,

387, 388, 389, 390, 391, 393, 395, 400, 403,

404, 407, 411, 413, 414, 415, 417, 420, 422,

423, 424, 425, 426, 429, 430, 431, 433, 435,

436, 439, 443, 445, 446, 448, 450, 452, 453,

454, 456, 458, 459, 460, 464, 466, 467, 473,

474, 476, 478, 479, 481, 483, 484, 486, 487,

488, 490, 492, 493, 494, 495, 496, 500, 502,

509, 512, 514, 515, 516, 518, 520, 521, 523,

524, 525, 526, 527, 528, 529, 530, 533, 534,

535, 536, 538, 539, 542, 546, 547, 549, 567,

568, 570, 572, 576, 577, 579, 592, 600, 601

Snowplanes, 14, 46, 50, 53, 54, 56, 59, 65, 72,

78, 158, 159, 190, 191, 194, 212, 214, 216,

225, 254, 255, 260, 261, 277, 278, 309, 310,

314, 334, 348, 349, 367, 376, 391, 404, 411,

418, 426, 427, 443, 456, 490, 512, 538, 539

Snowshoeing, 64, 132, 152, 154, 169, 214, 215,

228, 303, 305, 416, 417, 502, 503

Social effects, x, xii, xxviii, 12, 18, 27, 28, 32,

121, 131, 137, 141, 170, 230, 233, 234, 237,

241, 264, 324, 368, 406, 439, 469, 505, 507,

590, 591, 597, 605, 606, 608, 612, 631

Social values, xxviii, 131, 137, 230, 237, 264,

324, 368, 406, 439, 469, 505, 507

Socioeconomics, xxix, 19, 116, 121, 230, 235,

236, 237, 241, 259, 264, 540

Sound level, 48, 51, 54, 57, 63, 187, 431

Species of concern, 33, 184, 386

State Historic Preservation Office, 24, 116, 203,

256, 353

Static Peak, 48, 71, 176, 252, 286, 489, 517

Subnivian fauna, 117, 298, 308, 341, 346, 384,

389, 419, 424, 450, 454, 483, 488, 521, 525,

614

Swan, trumpeter (Cygnus buccinator), 66, 68,

118, 167, 184, 185, 252, 263, 299, 300, 301,

302, 390, 420, 484, 600, 626, 628, 629

Sylvan Pass, 64, 162, 170, 209, 269, 298, 410

Taggart Lake, xxvii, 48, 49, 50, 54, 56, 59, 61,

195, 200, 212, 216, 222
INDEX

520

Targhee National Forest, vi, 12, 174, 183, 211,

541, 543, 548, 551, 552, 553, 555, 558, 560,

561, 562, 564, 584, 586, 587

Teton Range, 71, 164, 178, 212, 489, 517, 598

The Fund for Animals, iv, ix, xi, 1, 6, 9, 11, 17,

24, 36, 76

The Fund for Animals Inc., iv, ix, xi, 1, 6, 9, 11,

17, 24, 36, 76

The Native American Graves Protection and

Repatriation Act, 66, 263

Threatened and endangered species, 482, 551,

565, 582, 589, 599, 630

Toad, boreal western (Bufo boreas boreas), 185

Top Notch Peak, 162

Tower, 47, 49, 51, 53, 55, 58, 64, 146, 207, 208,

209, 214, 215, 218, 222, 245, 282, 314, 337,

340, 344, 379, 383, 386, 481, 483, 486, 617

Triangle X, 50, 54, 56, 59, 61, 65, 178, 212, 214,

555

Trout, brown (Salmo trutta), 620

Trout, cutthroat, 185, 186, 631

Trout, rainbow (Oncorhynchus mykiss), 186, 273

Two Ocean Lake, 50, 54, 56, 65, 69, 166, 178,

216, 380, 382, 383, 384, 390

U.S. Department of Interior, i, 3, 5, 17

U.S. Fish and Wildlife Service, 6, 24, 25, 143,

165, 167, 174, 177, 178, 179, 181, 184, 186,

232, 249, 251, 566, 629, 630, 631

Uhl Hill, 48, 169, 173, 252, 380

Ungulates, i, xv, 32, 61, 67, 68, 69, 70, 71, 74,

169, 170, 171, 173, 177, 179, 180, 183, 251,

260, 279, 281, 282, 283, 285, 286, 287, 291,

297, 298, 305, 306, 309, 334, 335, 336, 337,

340, 341, 343, 344, 347, 377, 378, 379, 380,

382, 383, 385, 386, 387, 390, 414, 415, 416,

417, 422, 425, 446, 447, 448, 453, 455, 478,

479, 480, 481, 486, 489, 515, 516, 517, 523,

526, 548, 549, 557, 574, 583, 584, 598, 599,

600, 618, 621, 630

Ute Ladies’-tresses orchid (Spiranthes

diluvialis), 119

Vegetation, 5, 30, 66, 68, 118, 119, 120, 141,

146, 167, 168, 169, 170, 174, 175, 177, 186,

204, 209, 262, 270, 282, 291, 334, 353, 376,

414, 446, 478, 515, 595, 596, 615, 621, 623,

625, 626, 628, 629, 630, 631

Virginia Cascades, 49, 208, 215

Visitor access, i, viii, xiii, xiv, xxix, 8, 27, 48,

50, 56, 57, 67, 69, 70, 72, 205, 214, 231, 235,

249, 257, 258, 314, 316, 330, 331, 354, 355,

359, 360, 395, 398, 404, 431, 438, 460, 494,

497, 505, 507, 531, 534, 535, 569, 570, 571

Washburn Overlook, 58, 207

Wastewater, ix, 165

Water quality, 19, 28, 32, 164, 165, 166, 249,

250, 270, 271, 273, 274, 278, 300, 301, 303,

304, 305, 332, 334, 342, 374, 375, 376, 413,

420, 445, 451, 460, 476, 514, 521, 540, 568,

569, 570, 571, 572, 594, 595, 611, 618, 624,

631

Water resources, 13, 66, 116, 164, 249, 250, 262,

334, 376, 377, 414, 446, 478, 515, 568, 572,

592, 594, 595, 618, 623, 624, 631

West Thumb, xxvii, 49, 52, 55, 62, 64, 73, 193,

199, 203, 209, 210, 215, 222, 276, 277, 310,

311, 313, 315, 316, 332, 333, 348, 349, 350,

352, 357, 362, 374, 375, 381, 387, 391, 392,

393, 394, 397, 413, 428, 430, 432, 445, 457,

459, 461, 474, 475, 477, 491, 492, 493, 494,

496, 514, 527, 528, 530, 532

West Yellowstone, xi, xiii, xiv, xxviii, 13, 16,

35, 36, 47, 49, 50, 52, 53, 54, 55, 58, 62, 76,

78, 123, 126, 127, 128, 129, 134, 135, 141,

144, 149, 157, 173, 206, 207, 215, 225, 226,

227, 233, 241, 242, 243, 244, 245, 265, 266,

267, 269, 274, 282, 292, 301, 319, 320, 321,

322, 323, 324, 325, 326, 327, 328, 329, 330,

331, 336, 339, 354, 355, 356, 358, 359, 361,

362, 368, 369, 370, 371, 372, 373, 377, 378,

381, 385, 396, 398, 399, 400, 407, 408, 409,

410, 411, 440, 441, 442, 467, 468, 469, 470,

471, 472, 473, 495, 496, 497, 503, 504, 506,

507, 509, 510, 511, 541, 542, 543, 545, 551,

554, 560, 561, 564, 569, 571, 572, 573, 574,

575, 576, 577, 579, 580, 582, 590

Westslope cutthroat trout (Oncorhynchus clarki

lewisi), 185, 186

Wetlands, 5, 68, 116, 166, 167, 168, 185, 249,

270, 275, 276, 277, 278, 334, 376, 413, 414,

445, 476, 514, 609, 615, 621

Whooping Crane (Grus americana), 118

Wilderness, 19, 30, 32, 75, 76, 116, 120, 121,

143, 164, 165, 174, 189, 233, 546, 548, 549,

556, 557, 561, 570, 571, 594, 595, 627, 629,

630, 631

Wildlife impacts, 32, 67, 68, 161, 281, 282, 283,

284, 289, 292, 293, 294, 299, 302, 306, 307,

308, 330, 335, 336, 338, 341, 342, 344, 345,

347, 373, 378, 381, 384, 385, 386, 387, 388,

389, 415, 417, 418, 420, 421, 422, 423, 424,

443, 446, 447, 448, 449, 451, 452, 453, 454,

455, 479, 481, 482, 484, 485, 486, 487, 489,

512, 516, 518, 521, 522, 523, 524, 525, 535,

564, 592, 600

Wildlife impacts, displacement, 32, 117, 278,

280, 281, 282, 283, 285, 289, 291, 292, 293,

294, 295, 296, 297, 298, 299, 300, 301, 302,

303, 304, 305, 306, 307, 308, 335, 336, 338,

339, 340, 341, 342, 343, 344, 345, 346, 347,

377, 378, 379, 380, 381, 382, 383, 384, 385,

386, 387, 388, 389, 404, 415, 416, 417, 418,

419, 420, 421, 422, 423, 424, 425, 446, 447,

448, 449, 450, 451, 452, 453, 454, 455, 479,

480, 481, 482, 483, 484, 485, 486, 487, 488,

489, 515, 516, 518, 519, 521, 522, 523, 524,

525, 526, 539, 540, 541, 542, 543, 544, 545,
521

547, 548, 549, 552, 554, 558, 559, 560, 561,

562, 563, 564, 566, 573, 582, 583, 585, 592,

600, 603, 605, 626

Wildlife impacts, habituation, 118, 260, 279,

297, 305, 306, 340, 341, 344, 381, 382, 383,

387, 419, 422, 450, 452, 483, 486, 520, 523,

592, 600, 606, 621

Willow Flats, 48, 167, 168, 175, 252, 281, 284,

447

Wolf, gray (Canis lupus), 66, 67, 140, 154, 176,

178, 179, 263, 287, 292, 295, 296, 308, 380,

599, 613, 617, 626, 628, 630

Wolverine (Gulo gulo), 117, 182, 183, 298, 301,

304, 308, 346, 389, 424, 454, 488, 525, 600,

611, 615, 619, 620, 624, 627

Wyoming, i, vi, ix, x, xi, 12, 13, 14, 17, 19, 21,

24, 25, 47, 77, 119, 121, 126, 130, 131, 133,

137, 139, 144, 145, 146, 147, 164, 165, 167,

169, 175, 178, 179, 181, 182, 184, 186, 203,

205, 206, 209, 211, 215, 220, 225, 227, 230,

232, 238, 241, 256, 258, 259, 263, 271, 285,

286, 287, 300, 323, 352, 405, 468, 504, 506,

508, 539, 540, 544, 547, 551, 555, 563, 567,

568, 569, 570, 571, 572, 576, 581, 582, 583,

611, 612, 613, 614, 618, 619, 620, 621, 622,

625, 626, 627, 628, 629, 630, 631, 632

Yellowstone cutthroat trout (Oncorhynchus

clarki bouvieri), 185, 186, 631

Yellowstone National Park, i, iv, vi, ix, x, xii, xv,

xxvii, xxviii, xxix, xxx, xxxi, 1, 2, 3, 4, 9, 12,

13, 14, 16, 21, 22, 23, 31, 32, 33, 35, 36, 38,

48, 49, 50, 51, 52, 54, 57, 58, 59, 60, 61, 62,

63, 64, 68, 70, 71, 72, 77, 79, 89, 91, 93, 95,

97, 99, 101, 119, 120, 121, 126, 127, 129, 130,

131, 133, 134, 135, 137, 139, 140, 141, 142,

143, 144, 146, 147, 149, 151, 152, 154, 156,

157, 158, 160, 161, 162, 163, 164, 165, 166,

167, 168, 170, 171, 172, 174, 175, 176, 178,

179, 180, 181, 182, 183, 184, 185, 186, 189,

190, 191, 192, 193, 201, 202, 203, 204, 205,

206, 207, 211, 213, 214, 215, 216, 217, 218,

219, 220, 221, 222, 224, 225, 226, 227, 228,

230, 233, 237, 238, 239, 240, 241, 242, 243,

245, 246, 247, 249, 252, 253, 257, 258, 259,

262, 264, 268, 269, 271, 274, 275, 277, 278,

279, 280, 281, 282, 283, 284, 285, 286, 287,

289, 291, 292, 293, 294, 295, 296, 297, 298,

299, 300, 301, 302, 303, 310, 314, 317, 319,

320, 321, 322, 324, 325, 326, 330, 331, 334,

335, 336, 337, 338, 339, 340, 341, 342, 343,

344, 345, 346, 347, 348, 351, 354, 355, 358,

359, 360, 361, 362, 363, 367, 369, 373, 376,

377, 378, 379, 380, 381, 382, 383, 384, 385,

386, 387, 389, 390, 391, 393, 394, 395, 398,

401, 404, 405, 406, 410, 411, 413, 414, 415,

416, 417, 418, 419, 420, 421, 422, 423, 424,

425, 426, 431, 434, 436, 439, 443, 444, 445,

446, 447, 448, 449, 450, 451, 452, 453, 454,

455, 456, 457, 458, 460, 462, 464, 465, 466,

467, 468, 469, 470, 473, 474, 476, 478, 479,

480, 481, 482, 483, 484, 485, 486, 487, 488,

489, 490, 491, 492, 494, 495, 497, 498, 499,

500, 501, 502, 503, 504, 505, 506, 508, 514,

515, 516, 517, 518, 519, 521, 522, 524, 527,

529, 530, 531, 533, 534, 535, 536, 538, 543,

544, 545, 552, 553, 554, 555, 556, 557, 558,

559, 560, 562, 563, 566, 567, 568, 569, 570,

571, 573, 576, 577, 578, 579, 580, 583, 586,

587, 593, 594, 596, 597, 600, 611, 612, 613,

614, 615, 616, 617, 618, 619, 620, 621, 622,

623, 624, 625, 626, 627, 628, 629, 630, 631,

632

Yellowstone sand verbena (Abronia ammophila),

119

Zone 11, 47

Zone 9, 61