NATIONAL INVENTORY

AND ASSESSMENT

PROCEDURE—For Identifying

Barriers to Aquatic Organism Passage

at Road-Stream Crossings

United States

Department of

Agriculture

Forest Service

National

Technology and

Development

Program

7700—Transportation Mgmt

November 2005

FOREST SERVICE

DE P A R TMENT OF AGRICUL T U R E

Kim Clarkin—Project Manager

National Technology and Development Center

San Dimas, CA.

Anne Connor

USDA FS Clearwater National Forest, Orofino, ID

Michael J. Furniss

USDA FS Pacific Northwest Research Station, Corvallis OR

Bob Gubernick

USDA FS Tongass National Forest, Petersburg, AK

Michael Love

Michael Love and Associates, Eureka, CA

Kathleen Moynan

US Fish and Wildlife Service, Region 1, Portland, OR

Sandra WilsonMusser

USDA FS Region 6, Portland, OR

NATIONAL INVENTORY

AND ASSESSMENT

PROCEDURE—For Identifying

Barriers to Aquatic Organism

Passage at Road-Stream Crossings

U.S. Department of Agriculture Forest Service

National Technology and Development Program

444 E. Bonita Avenue

San Dimas, CA 91773

By:

Information contained in this document has been developed for the guidance of employees of

the U.S. Department of Agriculture (USDA) Forest Service, its contractors, and cooperating

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TABLE OF CONTENTS

I. Introduction ....................................................................................... 2

II. Geographic Scope and Specific Objectives of the Inventory ................. 5

A. Deciding where to conduct the inventory ..................................... 5

B. Deciding on inventory objectives ................................................. 6

III. Field Work Preparation ..................................................................... 10

A. Locating the crossings to be inventoried .................................... 10

B. Keeping track of the crossings ................................................... 11

IV. The Inventory ................................................................................... 12

A. Reviewing office information ...................................................... 12

B. Collecting the necessary equipment .......................................... 13

C. Training the field crew............................................................... 12

D. Conducting field work ............................................................... 12

E. Ensuring safe procedures .......................................................... 13

V. Passage Assessment......................................................................... 14

A. Developing the regional passage screen ..................................... 14

1. Introduction ........................................................................ 14

2. Screen criteria ..................................................................... 16

a. Crossings that resemble the natural channel ................. 16

b. Fishways: baffles and weirs ............................................ 17

c. Regionally defined analysis species criteria .................... 17

B. Conducting hydraulic analysis .................................................. 22

1. Flow selection...................................................................... 22

2. Swim performance .............................................................. 22

3. Fish Crossing limitations..................................................... 22

C. Summarizing crossing category for the analysis species ............ 22

VI. Prioritization of Road Crossing Treatments ...................................... 24

A. Establishing the larger watershed context ................................. 24

B. Protecting areas from invasive species....................................... 24

C. Developing a scheme for setting priorities ................................. 25

D. Finding sources of habitat quality and quantity information ..... 26

VII. References ...................................................................................... 28

Figures

V-1. Passage Assessment Process .......................................................... 15

V-2. First-phase Evaluation Filter developed for California .................... 20

V-3. Assessment Matrix Example from USFS Region 10 ......................... 21

Appendices

A. Example Prioritization Scheme: Rating Criteria from California........ 30

B. Fill-in-the-Blank Regional Screen, California model ......................... 33

C. Passage Flow Requirements from some States ................................. 34

D. Example Job Hazard Analysis—Umatilla National Forest ................. 35

E. Field Form and Line by Line Instructions ......................................... 37

ACKNOWLEDGMENTS

This procedure is based on several other fish passage evaluation procedures

including: Taylor and Love (2001), USDA Forest Service Region 10 (2001)

and USDA Region 6. We have also incorporated ideas from the Washington

Department of Fish and Wildlife’s manuals on fish passage design and

barrier assessment (Washington Department of Fish and Wildlife 2000).

Those sources are not responsible for any errors or misinterpretations herein.

1
I. INTRODUCTION

This inventory procedure is designed to be a nationally applicable, consistent

method of identifying crossings that impede passage of aquatic organisms

in or along streams. It is a how-to manual for approaching answers to two

questions raised in United States Department of Agriculture (USDA) Forest

Service Roads Analysis, [1999, p. 67, AQ(10)]: “How and where does the

road system restrict the migration and movement of aquatic organisms;

what aquatic species are affected and to what extent?”

Full answers to these questions are essential to managing roads and

planning for restoration. A transportation plan must consider and be

designed to mitigate the road network’s effects on aquatic ecosystems

and their continuity. And planning for restoring watersheds and setting

priorities cannot logically proceed without considering how fragmented the

aquatic habitat is and how important it is relative to the suite of restoration

needs of the whole watershed.

The inventory protocol is data-intensive because it is designed to produce

enough information from a single site visit to answer the following questions:

• Are crossing conditions are adequate for specific species and life stages?

• What is the approximate cost of replacement?

The inventory does not yield all the information needed to determine which

crossings should be prioritized for replacement. Generally, data on species

presence and habitat quality are needed in addition to the physical data

collected here. The inventory also does not yield enough information for

design of a replacement structure. Depending on the site, the design

process may require much more information, such as a full site survey

and a geomorphic assessment.

The site assessment procedure begins with an evaluation of the degree to

which a crossing resembles the adjacent stream form and function.

Crossings that maintain stream functions are essentially invisible to the

stream, and so are more likely to pass the resident species inhabiting the

stream. The research that could confirm the hypothesis that crossings

resembling the adjacent stream pass all resident aquatic and semi-aquatic

species has not been done. Given that direct evidence is unavailable, and

crossing assessment and restoration will proceed, it is reasonable to

assume that species movement needs will be accommodated by crossings

that do not disrupt the stream channel’s form and function.

If a crossing does not resemble the adjacent stream channel, then regionally

defined measurable criteria (hereafter referred to as regional screens) are

used for preliminary assessment of passage for a particular species, life

stage, or species group. For fish, a hydraulic model is available when the

regional screen fails to determine whether a crossing provides adequate

conditions for the analysis species. The model we use is FishXing, which

compares crossing hydraulics to swimming and leaping capabilities of

individual fish species and life stages. Regardless of whether the analysis

2
is completed using the screen or the model, the process results in a defining

a crossing category for each of the analysis species (see section V.C. for

category definitions). Consistent identification of crossing category for

individual species will permit unambiguous data aggregation across regions

and the nation.

Streams and roads that cross affect each other in important, potentially

destructive ways. Until recently, these two networks have been managed

relatively independently by different groups of resource specialists. The

sometimes destructive results have led to the realization that managing

streams and road must consider the needs and character of both, something

best accomplished by interdisciplinary teamwork. As noted in Roads

Analysis (USDA-FS 1999 p. 67), a successful approach to these problems

must draw from fisheries and wildlife biology, hydraulics, engineering,

geomorphology and hydrology. Ideally an interdisciplinary team of trained

specialists will be used to collect the data and interpret it in ways that

address management questions.

In most cases, fisheries issues usually prompt culvert inventories. But

many other aquatic and semi-aquatic species also use stream crossings and

are affected by even low volume roads: amphibians, reptiles, invertebrates

and small mammals. Information on passage needs and capabilities for

these groups is scarce, but some information can be found at

www.wildlifecrossings.info.

The following summarizes the barrier inventory-assessment process and

highlights important recommendations.

• Build and overlay maps of streams, roads, land ownership, analysis

species distributions, aquatic habitat types, and habitat quality.

• Population and habitat information from field surveys is highly preferred

because the assumptions used to estimate these variables from maps

are often inaccurate.

• Develop analysis species lists and criteria with the assistance of aquatic

experts and in collaboration with a group of stakeholders including land

management and regulatory agencies, as well as other interested parties

(such as, tribes, Departments of Transportation).

• Document assumptions and rationale.

• Include crossings on all land ownerships if possible; otherwise, conduct

the analysis recognizing the gaps in knowledge.

• Collect the entire suite of variables on all crossings to permit later

reevaluation if needed

• Use interdisciplinary teams to collect and interpret the data

Inventory and

Assessment

Procedure Overview

Establish the

watershed context

Collaboratively

establish criteria for

regional screens

Conduct the field

inventory

3
• Use regional screens for rapid field assessment of natural channel

simulation and barrier category.

• Use hydraulic analysis where screens fail to determine barrier category.

• Understand the limitations of the analytic procedure, such as:

o For many species, movement capabilities and needs are unknown.

o Estimates of culvert velocity are based on imprecise roughness

values and may not accurately reflect the flow conditions faced by fish.

• Set priorities for replacements aimed at maximum biological benefit in

conjunction with logistical considerations.

• Collaborate with partners and other stakeholders to set priorities.

Determine barrier

category: natural

channel resemblance

or species-specific

crossing category

Map barrier locations and

overlay on habitat-quality

maps to set priorities for

restoring connectivity

4
II. GEOGRAPHIC SCOPE AND SPECIFIC

OBJECTIVES OF THE INVENTORY

Unless resources are available to cover an entire area of interest, (such as

the whole forest), or funding is designated for a certain area, priorities must

be set among areas to inventory. Ideally, watershed analyses are complete,

and the road analyses are underway or complete. If so, answers to the

following questions will already be available. If not, an interdisciplinary

team should gather the background information needed to answer the

questions. It is essential to think in terms of watersheds, rather than just

about road systems, because the main issue is one of upstream-downstream

continuity for the local biota.

One of the functions of the barrier inventory is to identify the most

biologically beneficial improvements. To meet this objective, we need a

basic understanding of the needs of the biota and the condition of the

aquatic ecosystem in the general area. We need to answer questions like:

What spatial and temporal habitat needs are related to the life-history

requirements of the species? What are the general conditions of the

watershed’s habitats as related to species requirements? Do road and

topographic conditions in the watershed pose a risk to high quality habitats?

For example, are there miles of infrequently maintained unclassified or

legacy roads on steep lands, where crossing failures during floods could

damage downstream habitat?

This information can then be used to identify watersheds that are high

priority for barrier inventories. Some examples of watershed characteristics

that may lead to high priority for inventory are:

• Watersheds that are important refugia for certain species or aquatic

communities

• Watersheds that create a connected block of habitats needed to support

the life history requirements of species in the general area

• Watersheds with critical or essential habitat for one or more threatened

or endangered aquatic species or have species with economic or

cultural value.

• Watersheds with high native biological diversity

• Watersheds with known barriers excluding species from critical habitats

• Watersheds with habitat quality problems that could result in greater

species effects if barriers exist (such as, high temperature, low

dissolved oxygen, or low food productivity)

• Watersheds where barriers may be desired to exclude invasive exotic

species.

Other logistical or practical considerations may also focus an effort on a

particular watershed. For example, existing major road maintenance or

reconstruction needs, and existing or potential partnerships with other

landowners could also be criteria for selecting a watershed for inventory.

A. Deciding where to

conduct the

inventory

1. Which watershed(s)

should be surveyed

first?

5
Building a general picture of the watershed before planning the inventory is

essential for many reasons. An extensive coordination effort may be needed

to inventory crossings in an area with multiple jurisdictions. Generally, one

agency or entity spearheads the effort, with various amounts of commitment

from other landowners. Additional opportunities may be found for leveraging

funding from various sources when several landowners are cooperating to

assess barriers.

If cooperation cannot be secured, landowners may agree to inventory only

crossings on their own land or under their own jurisdiction. Information on

habitat quality and quantity—and on upstream and downstream barriers—

would still be needed for areas in the watershed under other ownership or

jurisdiction. Without that information, the importance of removing barriers

on any one jurisdiction may be hard or impossible to determine.

This inventory and assessment procedure supports one core objective and

three additional objectives.

The core objective is to determine the crossing category for each analysis

species.

The protocol includes two methods for achieving this objective. One method

uses species and lifestage specific criteria in a flow chart (see section V.A.

Regional Passage Screen); the other uses the hydraulic model FishXing (See

section V.B. Hydraulic Analysis). Headings in bold on the inventory data

sheets indicate the data are related to the core objective.

The additional objectives are to: 1) prioritize passage improvement

projects, 2) develop replacement project budget cost estimates, and 3) field

validate flows used to evaluate passage in FishXing. Headings in regular

font indicate the data are related to the additional objectives, and optional.

There may also be other objectives for conducting the inventory. For example,

a possible complementary objective is to assess crossings for risk of failure

during floods, and their probable consequences on downstream areas. See

#5 below for more information about this objective. The full set of objectives

should be identified prior to going into the field in order to ensure the data

needed to achieve those objectives are collected.

The field protocol described in this document will produce the information

needed to accomplish the core objective and the additional three objectives

listed above. To prioritize passage improvement projects, the inventory data

will need to be combined with an understanding of up-and downstream

habitat quantity and quality.

2. Will crossings on all

ownerships be

inventoried?

How will jurisdictional

boundaries be

handled?

Are there any

potential partners?

B. Deciding on

inventory objectives

6
1. Is the objective simply

to map sites that are

barriers?

Will you require

additional information

to help prioritize

passage restoration

projects?

The objectives for the inventory may be limited to defining the extent of the

barrier problems in a watershed. More often, they will be broader, and

include gathering information needed to prioritize crossings for treatment.

While there are likely to be a wide variety of prioritization criteria developed

by different administrative units, most will probably include information

about the quantity and quality of the habitat that would be opened up when

the site is improved. Both upstream and downstream movements can be

impeded by crossing structures depending on the species (Warren and

Pardew 1998), so it is important to understand the movement patterns

of the analysis species (and life stages) to determine which movements need

to be considered for prioritization. See section VI for more detail about how

habitat information is used in the prioritization process.

Unless an ecological reason exists for excluding species, the ideal crossing

is one that passes all aquatic and terrestrial species that require stream or

streamside zones to move8. Although definitive data are lacking, we believe

it is reasonable to assume that the aquatic and semi-aquatic organisms that

normally move through an area will be able to pass through crossings that

closely resemble the adjacent natural channel reaches. Such crossings

generally do not require species-specific analyses. [See section V.A.2.a for

criteria that can be used to determine if the crossing resembles the adjacent

natural channel.] Most crossings, however, do not mimic the adjacent

stream, and they require other methods of passage evaluation, including

comparing conditions at the crossing to regionally developed species-specific

criteria. For fish species with known swim performance, hydraulic

assessments can be conducted.

Information about how to assess road crossings for passage by amphibians,

reptiles, invertebrates, and small mammals is limited. These non-fish

species groups may or may not be a focus of the inventory; where they are,

passage determinations should be based on inferences from information

about the basic capabilities and needs of the species, and professional

judgments of experienced technical experts.

The Analysis Species—Passage determinations are based on criteria developed

from swimming and leaping capabilities of individual species, life stages

(size), or species groups with similar morphology or known swimming ability

and behavior (hereafter collectively referred to as the analysis species). The

procedure described in this document provides enough data to assess

passage for many fish species in many situations. Your list of analysis

species may be broader and include species other than fish, however.

Because additional data might need to be collected for these non-fish

species, we recommend identifying specific analysis species in the planning

stages. These are the species, life stages, or species groups for which

regional screens will need to be developed.

2. For what species, life

stages, or life stage

groups will passage

be evaluated?

8 Road construction and maintenance in streams is often permitted under the Corps of Engineers nationwide permit

that includes the following General Condition [65 FR March 9, 2000, page, 112893; Section C.4 Aquatic Life Movements]

“No activity may substantially disrupt the movement of those species of aquatic life indigenous to the waterbody

including those species which normally migrate through the area É Culverts placed in streams must be installed to

maintain low flow conditions”.

7
The following steps are recommended in choosing analysis species:

• Make a list of the species currently or historically present in the

inventory area that require passage.

• Contact state and federal agencies to determine if any species have

established passage requirements or recommendations.

• Review available information about the movement requirements of the

species on the initial list.

• Determine which species, life stages, or species groups have the

greatest movement limitations or are the species of concern in your

inventory area. These species should serve as the analysis species for

passage evaluations.

• Document the rationale for your choice(s) in the analysis species,

lifestage, or species group comment section on the field form, page 7

(such as, the weakest swimming species, lifestage, or species group,

an ESA-listed species, a culturally or economically important species,

an indicator species).

Although most crossings in the United States are culverts, crossings also

include fords, vented fords, and various types of bridges. Bridges are generally

assumed to be passable by all aquatic and most if not all riparian-dependent

species; but there may be instances where there are passage issues. Some

examples include: a short bridge that constricts channel width and increases

water velocity, or where rip-rap placed for scour protection results in rock

cascades that inhibit or prevent passage. Some structures that look like

bridges may in reality be a series of embedded box culverts.

Even though fords are low profile crossings, they can be and often are

barriers to aquatic species. For example, they may be:

• Low-flow barriers because of insufficient water depth, if the ford is too

wide at streambed elevation;

• Velocity barriers at moderate to high flows, if the floor of the ford lacks

sufficient roughness;

• Jump barriers, if perches have developed in the channel as a geomorphic

adjustment to the flow acceleration across the smooth surface.

Given the core objective, the inventory should include at least a qualitative

evaluation of passage at fords. The FishXing software does not address

low-water crossings, except for the culvert of a vented ford. True fords can

be hydraulically modeled by using open-channel flow models, but usually

low-water crossings will require field observations to determine with

confidence whether aquatic species can pass at the relevant times of year.

The field-form instructions indicate which measurements may pertain to

fords and how they are taken.

FishXing is the preferred software for assessing fish passage at culverts

because it not only models flow conditions over a range of flows throughout

the length of the structure, but it also compares those flow conditions to the

swimming and leaping abilities of fish species and life stages for which

information is available. The results identify the type and location of

migration barriers. FishXing is public domain software, well documented

and able to handle many culvert situations (see section V. B. for FishXing

limitations). This inventory protocol is designed to produce the data needed

3. Will all crossing

types be evaluated?

4. What hydraulic

assessment tool(s)

will be used to

evaluate crossings’

barrier category?

8
to analyze passage using FishXing. If another hydraulic model will be used

(such as HEC-RAS), additional input data are required.

Several issues other than those related to aquatic species could be

addressed in the crossing inventory, and they should be considered in

setting improvement priorities. For instance:

• Flood conveyance capacity (to ensure that crossings are sized to handle

the design flood);

• Crossing condition and maintenance needs; and

• Crossing failure risk and consequences of failure. An undersized culvert

in a steep stream moving large amounts of woody debris might be ranked

higher as a replacement priority because of its potential for plugging.

It would rate even higher if it has a high fill, has a high risk of failing

and could damage downstream aquatic habitat if it fails in a flood.

• Passage status for terrestrial wildlife that habitually use riparian areas

for movement.

This procedure includes data needed for flood conveyance capacity and

requires some observations of crossing condition and maintenance. Only

some simple components of a failure risk and consequences assessment

are included here. The reason is that a full assessment of failure risk and

consequences must be based on an understanding of geomorphic processes

throughout the watershed. In addition, the set of crossings where failure

would cause serious consequences to downstream resources is likely to

be different from (although it may substantially overlap) those that affect

aquatic species passage. For these reasons, combining inventories would

increase the amount of time and effort needed, which does not mean the

two should not be coordinated when feasible and efficient. For background

information on designing a failure risk and consequences assessment, see

Flanagan and others (1998).

The habits of terrestrial animals should be considered when evaluating

crossings. While salamanders swim or crawl in shallow-water margins and

between rocks and logs, some terrestrial animals seem to prefer to keep

their feet dry. The latter may prefer to climb up and over the fill, even if they

can walk through a culvert. This may be fine on a low volume road, but

undesirable on high traffic roads, where jersey barriers are placed at the

road edge, or where the fill is very high.

5. What other issues

besides aquatic

animal passage will

be addressed in

conjunction with the

passage inventory?

9
III. FIELD WORK PREPARATION

After the objectives, scope, and analysis species are defined, the next step

is to locate the set of crossings to assess in the inventory area. You might

include all crossings in the area, but more likely it will be a subset based

on your objectives and the resources available.

To identify the subset of crossings that affect the analysis species, overlay

maps of their distributions on a reliable map of road-stream intersections.

Geographical information systems (GIS) can be used to locate these

intersections, but only if the road and stream layers are sufficiently

reliable. Users are cautioned to have a clear understanding of the accuracy

of any GIS layers they use. Check the GIS road layer against aerial photos,

digital ortho-photographs, or satellite imagery to determine if some roads

were missed or were not correctly located.

Species distribution information may be available from several sources,

such as State and Federal agencies, Tribal governments, commercial

landowners or non-profit organizations. It should be remembered that

surveys for species presence have not always included smaller streams.

Species distribution maps may show a species is absent on small streams,

but this is not necessarily true, and it is a good practice to check species

presence up-stream during the crossing inventory. If no species presence

information is available, then it may be possible to estimate distribution

using criteria developed from areas which have been surveyed. For instance,

many units in the Pacific Northwest have assumed that fish do not occur

above stream gradients of 20 percent, and have not conducted passage

inventories on crossings on steeper streams. If you do this, be aware that:

1) your assumptions about habitat preferences may be incorrect, and

2) the topographic or other data used to screen out some crossings may

be inaccurate or low resolution. Experience in the Pacific Northwest shows

that fish are often in areas where biologists did not expect to find them.

Note also that not finding fish in one sampling event does not necessarily

mean they do not use the habitat at some time during the year.

It will be difficult to prioritize crossing restoration or determine where to

begin and end crossing surveys if species distribution information is not

available. Wherever possible a species inventory should accompany a

crossing inventory when species distribution information is unknown or

cannot be reliably predicted.

A final concern in identifying the subset of crossings to be assessed is land

ownership. As noted above, in areas of multiple land ownership, the owner

or road maintenance agency should be identified for each crossing. Make

sure each landowner has been contacted and ensure you have permission

to access the crossings on the dates of the inventory.

A. Locating the

crossings to be

inventoried

10
All National Forest system crossings should be identified by the INFRA

control number if the crossing is already entered in INFRA. However, the

inventory will usually include unclassified or unnumbered roads, and a

naming or numbering scheme needs to be developed so that each crossing

has a unique identifier. Because crossings missed on the maps are frequently

found in the field, having a contingency plan for numbering these missed

crossings is advisable. For example, all crossings might be numbered

consecutively as they are inventoried. Labels identifying watershed or district

or some other logical division so that the field forms can be easily sorted by

watershed are also a good idea. A field map should be maintained with all

the site locations and numbers.

B. Keeping track

of the crossings

11
IV. THE INVENTORY

Already completed broad-scale planning and assessment documents

(watershed and road analyses, road-management plans) may include

guidance for future management of the road or watershed to be inventoried.

These should be identified and reviewed.

Page 7 of the inventory form includes information on the location of other

crossings on the same stream, their barrier category, and the extent of

blocked habitat upstream. These data provide context for future project

planning. If any of this is unknown, you may want to gather this

information during the crossing inventory to facilitate prioritization.

Use this list (modified from Taylor and Love, 2002) to be sure you have the

equipment you need:

• Maps with site locations.

• GPS unit.

• Self-leveling level and tripod, acceptable instruments depend on the

site characteristics (see discussion above).

• Tapes (two): 300 ft and 100 ft in 1/10 ft increments.

• Clamps (to secure tapes for longitudinal profiles and cross-section

surveys).

• Leveling rod: 25 ft in 1/100 ft increments.

• Pocket leveling rod (to measure breaks-in-slopes within smaller

diameter culverts).

• Camera, film, and extra batteries.

• Compass.

• Waders, hip boots, and wading shoes (felt-soled).

• Safety vests if working on road with traffic.

• Hardhat.

• Flashlight or headlamp.

• First-aid kit.

Optional Equipment:

• Brush-clearing tools.

• Traffic cones.

Crews must consist of at least two people, although three would be ideal.

Higher production rates are obtained with a three-person crew, but more

importantly, there is a third person to help explore the details of the site

and bring additional skills to the team. Expect to spend one to two hours

surveying each crossing, depending on the difficulty of the survey and the

experience of the crew. Productivity will depend largely on travel time.

Since this inventory procedure brings several very different scientific fields

together for one task, there is a great opportunity to forge partnerships

across disciplines working in the same administrative unit. Ideally, the

A. Reviewing office

information

C. Training the field

crew

B. Collecting

the necessary

equipment

12
D. Conducting

field work

inventory team will be interdisciplinary and include crewmembers with

fisheries, hydrology/geomorphology and engineering survey experience.

Each of these disciplines brings important skills to the survey. Fisheries

biologists can evaluate species habitat use, hydrologists or

geomorphologists have expertise in river mechanics and stream behavior,

and engineers are best qualified to accurately survey the terrain. Field crews

can become familiar with the protocols by participating in a training

session, and by conducting test runs at specific sites to compare results

and discuss the methods. Results from several teams can then be used to

test measurement repeatability.

A survey crew should be ready to begin the inventory after hands-on training

by experienced personnel. Instruction should include techniques in surveying

profiles and cross-sections using an instrument at least as accurate as a

surveyor’s self-leveling level. Training should also include how to determine

what points to survey in order to accurately measure the topographic pontes

essential to categorizing crossing status. Note that hand instruments such

as hand levels, clinometers and abney hand levels do not possess the

accuracy necessary for this survey. Use of a higher order of hand instrument

such as a Rhodes Arc would also be questionable depending on site

conditions. Acceptable instruments depend on site characteristics (such as,

slope, site complexity, and need for turning points). The flatter the slope

and the more complex the site, the more accuracy is needed.

Fieldwork consists of visiting each crossing and collecting the physical

measurements needed to assess passage. The protocol also includes notes,

site sketches, and photographs describing the type and condition of each

crossing structure and illustrating adjacent channel and habitat conditions.

The inventory procedure is primarily designed to identify culverts that

obstruct or delay movement of on or more species and life stages. Pertinent

measurements and observations should also be taken for fords, unless the

inventory objectives exclude them.

Data sheets and instructions for the crossing inventory are located in

Appendix E. It is a good practice to regularly photocopy data sheets to

provide back-ups, and to regularly enter data into electronic databases

so that mistakes or missed data can be quickly noticed and corrected.

A job hazard analysis (JHA) is required before the inventory begins

(see example in Appendix D). Each crewmember should review the analysis

during training and in weekly safety meetings.

Use proper safety equipment and carefully assess the specific characteristics

of each crossing before conducting surveys. If the survey is being conducted

on a road open to traffic, consider placing signs (such as “Survey Party”)

to announce your presence to oncoming traffic from both directions.

Crewmembers should also wear bright orange vests to increase visibility.

Two-way radios provide effective communication between crew members

in spite of noise from road traffic and stream flow (Taylor and Love 2002).

Note: Field forms and instruction can be found in Appendix E.

E. Ensuring safe

procedures

13
V. PASSAGE ASSESSMENT

The assessment begins with a determination of whether the crossing

resembles the adjacent natural channel. The top box in Figure V-1 lists

specific criteria used to make this determination. The criteria are intended

to distinguish crossings that allow a wide variety of species to pass the crossing

including: amphibians, reptiles, some invertebrates, and numerous species

and life stages of fish. They are based on the presumption that if the culvert

physically resembles the adjacent channel, then flow and substrate conditions

within the culvert will be similar enough to allow passage at the same times

animals are moving in the natural channel. If a species has a critical movement

window of only a few days, and this happens to coincide with above-bankfull

flows in a specific year, these criteria would not assure passage.

When crossings do not resemble the natural channel they are taken to the

next step in the screen. In this step, the crossing is compared to regionally

or locally developed screen criteria that specifically address the passage needs

of the analysis species. Examples of these screens are shown in Figures V-2

and V-4. The screening procedure is designed to quickly classify crossings

into passage categories for each analysis species, species group, or lifestage.

The screen will not cover all possible scenarios. Some crossings have

characteristics that may hinder passage but are not included in the

screen—for example, debris or sediment blockages, debris screens and

trash racks, and drop-inlets. We recommend using the screen criteria to

categorize the crossing before leaving the site to permit the field crew to

validate the result based on their observations.

FishXing would be used when the result of the screen places the crossing in

the “indeterminate” category (that is, when screen criteria can not determine

whether the crossing conditions are adequate or inadequate). There are

some situations, such as culverts with baffles, weirs or other fishways,

where the crossing category cannot be determined by either the regional

screens or FishXing. These situations require field monitoring or detailed

mathematical modeling.

A. Developing the

regional passage

screen

1. Introduction

14
Figure V-1. Passage assessment process

Does the crossing structure currently

simulate stream conditions

(width, gradient and substrate)?

Criteria: Inlet width >

 bankfull

Streambed Channel No perch

Substrate width or oulet

throughout and andjump

Does the crossing structure meet regionally defined,

species-specific thresholds?

Criteria that may be useful in defining passability:

Inlet width to active channel or bankfull width ratio

Perch or outlet drop

Slope

Backwater or residual inlet depth (low flow depth in crossing

greater or equal to low flow depth in adjacent channel)

Inlet gradient

% blockage

baffles / weirs (undetermined)

See figures V-2 and V-4 for examples of regional criteria

Use FishXing software to model crossing

hydraulics and compare to species capabilities

Field Study / Direct Observation/Mathematical Modeling

Yes

Yes

No

Resembles

natural channel

Passage

conditions

adequate for

analysis species

Passable

conditions

adequate for

analysis species

Indeterminate by model

(weirs / baffles / some fords) /

Indeterminate using regional criteria

Passage

conditions

inadequate

for analysis

species

Passage

conditions

inadequate

for analysis

species

15
a) Crossings that resemble the natural channel

Characteristics that indicate that the crossing resembles the natural

adjacent channel include:

• Streambed substrate is continuous throughout the crossing and the

streambed slope, particle size and arrangement are similar to the

adjacent channel;

• The crossing does not constrict the bankfull channel width. To meet

this criterion, the inlet width must at least match the natural channel

bankfull width, usually measured upstream of the structure and away

from its zone of influence.

Note that these criteria are not necessarily the ones that would be used to

design ‘stream simulation’ crossings.

Streambed substrate continuity—For crossings to resemble the natural

channel, they must be able to transport all watershed products moving in

the stream channel at least up to bankfull flow. Where this goal is met, bed

material size, arrangement, and slope profile inside the structure are either

similar to the adjacent channel sections, or they are designed to provide a

similar rate of energy loss. In the field, evidence of similarity in embedded

structures that have been in place for several years is: lack of bedload or

debris accumulation upstream of the structure (caused by the structure),

lack of downstream scour, and low flow depths similar to those in the

natural channel. Upstream of the structure, look for unusual bank erosion,

and for finer bed material and lower slopes than in adjacent sections

(evidence of aggradation). Downstream, look for abrupt slope changes and

larger bed material (evidence of degradation). Keep in mind that nearby

tributaries can modify streambed particle sizes as well. Also keep in mind

the age of the structure. If it is new, the channel may still be adjusting to

installation, so determining whether the crossing will function like the

adjacent natural channel may not be possible.

On slopes lower than about 3 percent, bed material size, arrangement

and slope profile in the structure are expected to be identical to the nearby

stream sections. On higher slopes, bed material may be larger than in the

natural channel, in order to resist movement during larger than bankfull

flows. To qualify in this category, however, the bed material must be

arranged into stable bedforms that provide for flow diversity, energy

dissipation, and continuity of bedload transport through the structure.

For the purposes of this inventory, it is recommended that crews rely on

the observations outlined above to make that determination.

Bankfull channel width—Compare the average of the adjacent bankfull

channel widths recorded on page four of the field form to the width of the

structure opening. Where channel types differ above and below the crossing,

you will need to judge which width should be matched. Bedslope, bedforms,

and width must all work together to maintain continuity of transport

through the reach.

Regional adjustment of these criteria for natural channel resemblance will

probably not be required.

2. Screen Criteria

16
b) Fishways: baffles and weirs

Many culverts have been modified or retrofit with baffles or weirs for fish

passage. Baffles and weirs typically act to reduce velocities, provide resting

pools, and consolidate low flows to provide more suitable depth. These

structures are sometimes installed to retain streambed material inside the

pipe. Where these are completely embedded the crossing can be considered

to have continuous substrate. Baffled culverts that are not completely

embedded are not easy to screen because the hydraulics can be complicated—

even unsolvable. Many baffled culverts require field study to determine their

passage category and are initially put in the ‘indeterminate’ category.

c) Regionally defined analysis species criteria

If the structure does not simulate the natural channel, then continue through

the portion of the flow chart (Figure V-1) that includes the regionally developed

analysis species criteria. Regional analysis species criteria are thresholds

that reflect the species, life stage, or species group’s ability to swim through

or leap into crossing structures. If a culvert meets the regional analysis

species criteria, then the passage conditions are categorized as adequate.

If the regional criteria are not met, then either passage is inadequate or

indeterminate using the screen. If it is indeterminate, then other analyses

(eg. FishXing, monitoring) are needed.

The screening procedure should quickly classify crossings into one of four

categories:

• Crossing resembles adjacent channel: passage assumed for aquatic species

• Meets criteria: passage conditions are adequate for the analysis species

for which the screen is designed

• Fails criteria: passage conditions are inadequate for the analysis

species for which the screen is designed

• Indeterminate barrier category: requires hydraulic or other analysis.

These barrier categories are species specific, so it is possible for a crossing

to be in more than one category (eg. adequate for adults, indeterminate for

juveniles).

The benefit of developing regional screens is that they speed up the process

of categorizing many crossings. Where we can define certain observable

characteristics (such as perch height) that make a crossing impassable for

most individuals of the analysis species, this method is more efficient than

hydraulic analysis. The risk, of course, is that we may not have all the

information to select solid criteria, and so best professional judgment must

frequently be used. Thus we are always at some risk of placing crossings in

the wrong category.

It is important to remember that barrier determination is not an exact science.

As with all biological characteristics, a range in swim performance is found

when individuals are tested. Also, field conditions may vary considerably

from those in a laboratory where much of the swim performance data are

gathered. Swim performance data should be considered as a guidepost and

you must use judgment to construct the screens.

17
If the screen criteria are based on the lowest numbers in the range reported

for swim or leap performance for the analysis species, then some of the

crossings will be placed in the “passage condition inadequate” category when

they are actually passable to most individuals. If the criteria are based on

the upper end of the range, then more crossings will fall in the “indeterminate”

category, requiring the use of the hydraulic model. Inventory, analysis, and

repair of culverts are expensive, and restoration dollars are limited. It is,

therefore, important to consider the consequences of choosing criteria from

various portions of the swim performance ranges reported in the literature.

It is our recommendation that screens be tested on a sample of crossings

that cover the full range of categories. A group of experienced professionals

should be familiar with the test crossings and agree about their category.

Testing will help to make sure the screens are performing as expected.

At least three screens have been developed to identify fish-passable crossings

without a hydraulic analysis. Two are described here as examples, along

with some discussion of the logic behind the criteria. Each of these screens

is the result of substantial experience in assessing culverts for salmonid

passage. The examples presented here may not be appropriate outside the

regions for which they were developed. Remember that these screens were

developed by regional teams representing agencies and organizations with

interest in fish passage. If passage for non-fish species is important in your

area, you may develop several screens for a broader range of analysis

species. Regional screen development teams should include fish and wildlife

management agencies and road managers of all jurisdictions. If this is done,

barrier determinations will rest on a consensus definition that meets legal

standards, and the data can be aggregated across the various ownerships

in a watershed. Certainly, decisions about variables and values within any

regional screen should be justified and documented.

The screen referred to above, but not presented here as an example, is

included in the Washington Department of Fish and Wildlife’s Fish Passage

Barrier and Surface Water Diversion Screening Assessment and Prioritization

Manual, August 2000. See page 17 at www.wa.gov/wdfw/hab/engineer/

fishbarr.htm.

Example 1: California’s first-phase passage evaluation filter

The flowchart screen (Figure V-2) is from Taylor and Love (2002). It is designed

to cover both adult and juvenile anadromous salmonids. It puts crossings into

three categories: red, gray, and green. Definitions in this scheme are as follows:

• Green: Conditions are assumed adequate for passage of all salmonids.

Even the weakest swimming lifestage (juveniles) can pass the crossing

during the entire period of migration.

• Gray: Conditions may not be adequate for all salmonid species or life

stages presumed present. Additional analyses are required to determine

extent of the barrier for each species and lifestage.

• Red: Conditions do not meet passage criteria over the entire range of

migration flows for even the strongest swimming species and lifestage

(adults) presumed present. Assume ‘passage condition inadequate’.

The crossings that resemble the adjacent natural channel are categorized as

green (see the left-hand side of this screen). They have streambed substrate

18
throughout and inlets as wide as the active channel. If either one of those

criteria are not met, a crossing can still be considered “green”, but only

when its entire length is backwatered at extreme low flows (see Figure E-14

for illustration of ‘residual inlet depth’). These criteria are designed so that

even the weakest lifestage can pass a green crossing. Criteria leading

to a red call are an outlet drop of 2 feet or greater, or a steep slope without

baffles or weirs to modify velocity and depth. Other crossings are partial

or unknown barriers, and the barrier category is undefined until hydraulic

analysis is completed.

In this screen, the values assigned to critical variables are conservative, to

accommodate passage by weaker-swimming individuals. Stronger (larger)

individual fish can often pass successfully upstream through a red culvert

under certain flows. The values also incorporate current National Marine

Fisheries Service guidelines and California Department of Fish and Game

design standards.

A benefit of using a flow-chart model is that values of specific variables can

be easily changed to judge the sensitivity of the model to data sets. But

because the California model covers all crossing structure types with one

set of criteria, it does not allow the user to distinguish crossings that may

permit easier passage than others (for example, larger corrugations on

metal pipes). The California flowchart also includes all species of concern

(namely, adult and juvenile coho salmon) in one flow chart, which results in

a number of gray culverts. It would be possible to reduce the number of

gray culverts and the required additional analysis by constructing two

flowcharts, one for adult and one for juvenile fish. With two flowcharts

many culverts would probably be red for juveniles (needing no more

additional analysis) and gray for adults (needing additional analysis with

FishXing).

For regional teams wanting to use the flow-chart model to develop regional

species or species-group criteria for an initial screen, we have included a

fill-in-the-blank version in Appendix B. Brief explanations of the criteria are

included there. Note that the example variables may or may not be

appropriate for all species. Other types of information may be required for

passage of amphibians, reptiles, invertebrates, or small mammals.

19

Example 2: Alaska’s initial screen

The screening matrix developed in Alaska (by a group comprising USFS

Region 10, the Alaska Department of Fish and Game, Alaska Department

of Transportation, the Environmental Protection Agency, and the FishXing

development team) is for juvenile coho salmon only. It is applied for juveniles

of all species in southeast Alaska (Figure V-4). This matrix explicitly

recognizes the mix of characteristics that, if present together, permit passage

for juvenile fish through the various listed crossing types. Building a detailed

matrix like this one obviously requires considerable information on the

movement of the analysis species and direct experience observing movement

through many different crossing structure types. Note that crossings

passable by adult but not juvenile fish are red, unlike in California where

they would be gray.
YES

Figure V-2. EXAMPLE ONLY: Green-Gray-Red screen developed for California’s anadromous adult and

juvenile salmonids (Taylor and Love 2002).

20

YES NO

YES

YES

YES

YES

YES

YES

NO

NO

NO

OR

NO

NO

NO

Calculate: Calculate: average active channel width,

 culvert slope, residual depth at

 inlet, and drop at outlet

Streambed

substrate

throughout culvert

No Outlet Drop

and Residual Inlet

Depth > 0.5’

Outlet Drop > 2’

Slope > 3%

and contains No

baffles/weirs

Culvert contains

baffles or weirs for

fish passage

Outlet Drop < 2’

Slope < 2%

Gray

Red

Green

Gray

Red

Green

Inlet Width > Active

Channel width

No Outlet Drop

and Residual Inlet

Depth > 0.5’

Outlet Drop > 2’
Figure V-3. Alaska fish-passage evaluation criteria (juvenile coho) USDA Forest Service Region 10

Bottomless pipe arch or

countersunk pipe arch, substrate

100% coverage and invert depth

greater than 20% of culvert rise.

Countersunk pipe arches (1x3

corrugation and larger). Substrate

less than 100% coverage or invert

depth less than 20% of culvert rise.

Circular CMP 48 inch span and

smaller, spiral corrugations,

regardless of substrate coverage.

Circular CMPs with annular

corrugations larger than 1x3 and

1x3 spiral corrugations (>48"

span), substrate less than 100%

coverage or invert depth less than

20% culvert rise.

Circular CMPs with 1x3 or smaller

annular corrugations (all spans)

and 1x3 spiral corrugations (>48"

span), 100% substrate coverage

and substrate depth greater than

20% of culvert rise.

Circular CMPs with 2x6 annular

corrugations (all spans), 100% substrate

coverage and substrate depth

greater than 20% of culvert rise.

Baffled or multiple structure

installations

Log stringer or modular bridge

Structure Green1 Gray2 Red3

1

2

3

4

5

6

7

8

Installed at channel grade (+/-

1%), culvert span to bedwidth

ratio of 0.9 to 1.0, no blockage.

Grade less than 0.5%, no perch,

no blockage, culvert span to

bedwidth ratio greater than 0.75.

Culvert gradient less than 0.5%,

no perch, no blockage, culvert

span to bedwidth ratio greater

than 0.75

Grade less than 0.5%, no perch,

no blockage, culvert span to

bedwidth ratio greater than 0.75.

Grade less than 1%, no perch, no

blockage, culvert span to

bedwidth ratio greater than 0.75

Grade less than 2.0%, no perch,

no blockage, culvert span to

bedwidth ratio greater than 0.75

No encroachment on bedwidth.

Installed at channel grade (+/-

1%), culvert span to bedwidth

ratio of 0.5 to 0.9, less than or

equal to 10% blockage.

Grade between 0.5 to 2.0%,

less than 4" perch, less than or

equal to 10% blockage, culvert

span to bedwidth ratio of 0.5 to

0.75.

Culvert gradient 0.5 to 1.0%,

perch less than 4 inches, less

than or equal to 10% blockage,

culvert span to bedwidth ratio of

0.5 to 0.75.

Grade between 0.5 to 2.0%,

less than 4" perch, less than or

equal to 10% blockage, culvert

span to bedwidth ratio of 0.5 to

0.75.

Grade 1.0 to 3.0%, perch less

than 4 inches, less than or

equal to 10% blockage, culvert

span to bedwidth ratio of 0.5 to

0.75.

Grade 2.0 to 4.0%, less than 4"

perch, less than or equal to

10% blockage, culvert span to

bedwidth ratio of 0.5 to 0.75.

All

Encroachment on bedwidth

(either streambank).

Not installed at channel grade

(+/- 1%), culvert span to

bedwidth ratio less than 0.5,

greater than 10% blockage.

Grade greater than 2.0%,

greater than 4" perch, greater

than 10% blockage, culvert

span to bedwidth ratio less

than 0.5.

Culvert gradient greater than

1.0%, perch greater than 4

inches, blockage greater than

10%, span to bedwidth ratio

less than 0.5.

Grade greater than 2.0%,

greater than 4" perch, greater

than 10% blockage, culvert

span to bedwidth ratio less

than 0.5.

Culvert gradient greater than

3.0%, perch greater than 4

inches, blockage greater than

10%, culvert span to bedwidth

ratio less than 0.5.

Grade greater than 4.0%,

greater than 4 inch perch,

greater than 10% blockage,

culvert span to bedwidth ratio

less than 0.5.

Structural collapse.

Example Only

Note: Larger corrugations increase roughness allowing for fish passage at steeper culvert gradients.

1Green – Conditions at the crossing are assumed adequate for fish passage

2Gray – Conditions at the crossing may not be adequate for fish passage, additional analysis required.

3Red – Conditions at the crossing are assumed to be not adequate for fish passage, additional fieldwork and analysis required.

21
When the status of a crossing cannot be determined by applying the regional

screens, hydraulic modeling can often be used to determine if the crossing

has adequate passage characteristics for the analysis species.

Hydraulic models require the user to select the pertinent flows. Designing

road crossings to pass fish at all flows is impractical (NMFS 2000; Robison

and others, 2000; WDFW SSHEAR 1998). Most aquatic species take refuge

during larger flood events. Conversely, during low flow periods shallow water

depths in many small streams can make the channel itself impassable.

Generally there will be an upper and a lower flow threshold beyond which

passage need not be accommodated. In some areas, fish management or

regulatory agencies have defined the range of flows where movement must

be accommodated (See appendix C).

The field data needed to support the FishXing software are gathered during

this inventory. FishXing is available on line at www.stream.fs.fed.us/fishxing.

The current version (2.2) calculates velocities and depths throughout the

pipe for a specific flow and then compares them to default or user-input

values for fish swim speeds and depth requirements. The default values

should not be assumed appropriate across regions. Developing a regional

model should include selecting user-input values for swimming ability. The

program identifies the locations of velocity and lack-of-depth barriers in the

pipe, and the jump height barriers at perched outlets.

FishXing models a limited set of the most common culvert shapes It does

not model complex crossing structures such as multiple pipes, aprons,

fords or culverts with internal grade breaks, (although multiple runs can

sometimes simulate this condition). The software calculates a composite

roughness value for pipe bed and walls at each node in the pipe (about

every 3 feet) based on water depth (the solution is iterative because depth

and composite roughness are interdependent variables). FishXing assumes

that embedded and open bottom culverts have flat homogeneous beds.

This frequently results in a “passage condition inadequate” determination,

because true low flow depth is underestimated. For this reason, FishXing

should be used with extreme care, if at all, when there is continuous

streambed material through the crossing structure.

Other hydraulic evaluation models include CulvertMaster (http://

www.haestad.com), the Federal Highways Culvert program HY-8 and HECRAS. The Federal Highway Administration Bridge Technology website http:/

/www.fhwa.dot.gov/bridge/hydsoft.htm) includes links to several of these

software packages. These models do not incorporate the swim performance

information that FishXing offers, and additional calculations comparing fish

swim performance to the hydraulic properties in the pipe are required.

Some crossings block all species and life stages at all flows, others block

some species and life stages only at certain flows, and still others block

some species and life stages at all flows. These characteristics can be crucial

for prioritizing passage restoration projects. While it is tempting to describe

crossings as “partial” or “total” barriers, the meaning of these terms has not

B. Conducting

hydraulic analysis

1. Flow selection

2. Swim Performance

3. Fish Crossing

Limitations

C. Summarizing

crossing category

for analysis

species

22
been standardized. Important information is lost when these terms are

used; for example: what does partial mean? Is it a barrier some of the time

for all species present, or all of the time for some of the species present?

Because these terms are vague and easily misinterpreted, we recommend

that summaries be limited to tables that list the analysis species and its

crossing category from the screening process (such as, passage condition

adequate, passage conditions inadequate, indeterminate). Consistent use of

these terms by units using this protocol will permit information exchange

and prioritization across units and jurisdictions. [The meanings of these

terms are essentially the same as the green, red, and grey used by previous

inventory protocols. Each protocol uses different regional criteria to define

green, grey and red, just as different geographic regions will need to use

different criteria to define adequate, inadequate and indeterminate.]

23
VI. PRIORITIZATION OF ROAD

CROSSING TREATMENTS

Stream restoration projects, such as removing passage barriers, are most

effective when they are planned and priorities are set based on an understanding

of the watershed’s condition, use by resident biota, its production potential,

and its relation to the larger basin. For example, two streams similar in size

and type of barrier problems could have very different priorities if one is

tributary to an area of high fish production, while the other is not. To fully

understand passage restoration needs in a drainage system, we need to

understand the ecology of the local biota. What role does the blocked area

play in the life history of individual animals, and in the structure and

dynamics of populations or communities? What are the biological

consequences of not restoring passage? The nature and importance of

ecological consequences of a barrier is the standard against which passage

restoration costs must be weighed. An understanding of the other restoration

needs within the watershed is also crucial. For example, fixing passage

barriers may be less important if water or habitat quality is low. A watershed

approach (McCammon et al 1998) should be taken to ensure that priorities

are set based on a full assessment of watershed conditions, not on a limited

site-scale view.

Where transportation plans are completed, they are an important part of

establishing the context for restoration. The long term plans for the road

can inform decisions about whether or not to restore passage at the culvert.

It may be that the road is planned for removal or upgrade; if so, passage

issues can be addressed when the removal or upgrades are done.

Before any treatment planning starts, consider these questions: Are exotic

invasive species present in the area? Should barriers be maintained?

In freshwater ecosystems, non-native invasions are one the primary causes

of species extirpations and population declines (Miller and others 1998, Allan

and Flecker 1993). Crossings sometimes inhibit upstream spread of non-native

or undesirable species. However, if exclusion is truly desired, an obstruction

should be designed to keep the specific invader from moving upstream.

Crossings often function as incomplete barriers to upstream movement.

Passage may be possible during certain infrequent flow events, or larger

individuals may be able to pass at some flows. Also, while it may be possible

to protect a native species by retaining a crossing barrier, this may also have

the undesirable effect of increasing that population’s extinction probability.

Barriers can prevent re-colonization of the upstream reaches after catastrophic

disturbances (Brown 1986, Frissell 1993, Angermeier 1995). The tradeoffs

related to improving access at road crossings when non-native species are

present should be very carefully considered.

A. Establishing the

larger watershed

context

B. Protecting areas

from invasive

species

24
This discussion relies heavily on Taylor and Love (2002).

Because sufficient funding in any one fiscal year to correct all passage

problems is unlikely, setting priorities is usually necessary. Some federal,

state and local agencies, tribes, and watershed councils may already have

developed methods for setting priorities based on local issues and species

needs. If your local area does not already have a plan, what follows can help

you and your partners develop a method that ranks road-crossing

treatments by whatever combination of criteria is most critical.

When you develop your scheme for ranking treatment of road crossings

consider the following:

• Quantity and quality of upstream and downstream habitat that would

be made accessible.

Example 1: A somewhat shorter but higher quality habitat may be more

important to open up than a lower quality, but longer, habitat area.

Example 2: Seasonal water-quality problems may increase the

importance of ensuring access between stream sections because aquatic

species’ survival may depend on their ability to move in response to

seasonal changes in water quality. For example, juvenile salmonids

may need to move to cooler tributaries when mainstream channel

temperatures rise in summer.

• Species status

Passage problems affecting ESA-listed species should rank higher than

those affecting species not currently imperiled.

• Crossing failure risk

Potential adverse effects to aquatic systems will be avoided by replacing

crossings at high risk of failing because they are undersized or in poor

condition.

• Presence of upstream and downstream barriers (movement requirements

vary by species and life stage).

Example 1: For anadromous fish species, the presence of other barriers

downstream is an important issue because their survival depends on

having accessible stream corridors from the ocean to upstream spawning

grounds. Fixing upstream barriers is less productive when downstream

barriers are still in place. Effective treatments generally proceed in an

upstream direction.

Example 2: For resident species, individuals need to move in both

directions to avoid predators, find mates or food, or reduce competition

for local resources.

• Habitat use

Opening corridors to high quality habitat may be more important than

fixing barriers across several drainages.

• Extent to which the barrier blocks native or desirable aquatic species,

or alters native biological diversity.

Removing a total barrier will assist more species and life stages than

removing a partial barrier, and so may be more effective in re-establishing

the native biological community. Also, restoration of access in areas

where native biological diversity is intact may have higher priority than

an area where native biodiversity has already been compromised.

When considering which species are excluded, considering the role of

barriers in preventing exotic species invasion.

C. Developing a

scheme for setting

priorities

25
• Known barriers.

Restoring passage where attempts to pass frequently fail and where

predators or poachers congregate to take advantage of the blocked

animals may be more important than other places. These sites also

have a high probability of fostering immediate recolonization of

upstream habitat.

The objective of setting priorities is to assess the biological risks and

consequences of crossing barriers and to rank them in order of importance

for passage restoration. Naturally, other factors—such as social, economic,

or scheduling efficiencies—will enter into the actual scheduling of treatments.

For example, equipment move-in costs may make addressing all barriers on

a particular road system at the same time more economical, even though

some of the crossings are of low biological priority.

Schemes for setting priorities can be simple or complex depending on your

local capabilities and needs. Keep the scheme as simple and clear as possible

for consistent application so that your prioritization decisions can be easily

explained. An example scheme slightly modified from one being developed

in California is shown in Appendix A.

Information about habitat upstream and downstream of culvert locations

can be obtained from previously conducted habitat typing or population

surveys. Habitat information is often available in reports on file at state Fish

and Wildlife agencies, federal (FS, BLM, EPA), or tribal offices. Private sector

biologists, watershed groups, coordinators, restorationists, and large

landowners can assist in acquiring additional information on drainages in

their jurisdictions.

Information on habitat quality throughout the watershed is needed to provide

a watershed-scale context for each barrier culvert. Some examples:

• Certain blocked areas may be able to provide high-quality winter

rearing in a watershed where that type of habitat is critically short;

• The area downstream of a crossing with a high risk of failure in a flood

might be extraordinary habitat for an endangered species; and

• A barrier culvert may be protecting an endangered amphibian from

predation by introduced fish.

Quantitative field assessments of habitat quality are desirable, but if none

are available then other types of information can be used as indicators of

habitat quality. Examples include disturbance indicators available on GIS

coverages, such as the percentage of watershed area in young vegetative

stands (recently harvested), road density, riparian area grazing density,

mining disturbance acres, and the amount of impervious surface or

urbanization. Note that these indicators are much less reliable than habitat

quality variables measured or even estimated in the field. Their relation to

habitat quality is frequently indirect, and real habitat quality may or may

not reflect the assumed relations. At a minimum, we recommend that a

fisheries biologist or aquatic scientist look at the stream to estimate its quality.

D. Finding sources

of habitat quality

and quantity

information

26
Summer water-temperature or other water quality data are helpful in

identifying tributaries that may provide high quality habitat. Knowledge about

water quality can help to identify water-quality refuges and non-structural

impediments to movement from poor quality to higher quality habitats.

Such movements are often key to the growth and survival of aquatic

organisms. This information may be available from state environmental

agencies for streams listed on 303(d) lists as having beneficial use

impairment (such as, temperatures outside natural regime, low dissolved

oxygen, elevated toxins).

NOTE: Field forms and instructions are located in Appendix E.

27
VII. REFERENCES

Allan J. D., and A. S. Flecker. (1993) Biodiversity conservation in running

waters. Bioscience 43:32-43.

Angermeier, P. L. (1995) Ecological attributes of extinction-prone species: loss

of freshwater fishes of Virginia. Conservation Biology 9:143-158.

American Association of State Highway and Transportation Officials. (2000)

Standard Specifications for Transportation Materials and Methods of Sampling

and Testing Part 1 – Specifications. Twentieth edition. www.aashto.org

American Iron and Steel Institute. (1994) Handbook of Steel Drainage &

Highway Construction Products. 1994. Fifth edition. AISI, Washington, DC.

Brown, K. L. (1986) Population demographic and genetic structure of plains

killifish from the Kansas and Arkansas River basins in Kansas. Transactions

of the American Fisheries Society 115:568-576.

Flanagan, S.A., M.J. Furniss, T.S. Ledwith, S. Thiesen, M. Love, K. Moore,

and J. Ory. (1998) Methods for Inventory and Environmental Risk

Assessment of Road Drainage Crossings USDA Forest Service Technology

and Development Program, San Dimas, CA.

Frissell, C. A. (1993) Topology of extinction and endangerment of native

fishes in the Pacific Northwest and California (USA). Conservation Biology

7:342-354.

Harrelson, C.C., C.L. Rawlins, and J. P. Potyondy. (1994) Stream Channel

Reference Sites: an Illustrated Guide to Field Technique. USDA FS GTR RM-245,

Rocky Mountain Forest and Range Experiment Station, Ft Collins, CO. 61 p.

McCammon, B., J. Rector, and K. Gebhardt. (1998) A Framework for Analyzing

the Hydrologic Condition of Watersheds. USDA-FS and USDI-BLM. BLM

Technical Note 405.

Miller, R. R., J. D. Williams, and J. E. Williams. (1989) Extinctions of

North American fishes during the past century. Fisheries 14:22-38.

Moser, M. (1999) Low Light Impediments to Fish Migration with Particular

Emphasis on River Herring. Web Presentation of The CTE/NCDOT Research

Forum. http://carey078.itre.ncsu.edu/fishmigration.html

Normann, J. M., R. J. Houghtalen and W. J. Johnston. (1985) Hydraulic

Design of Highway Culverts Federal Highway Administration, Report No.

FHWA-85-15. recently updated: FHWA NHI-01-020 (2001).

Robison, E.G., A. Mirati, and M. Allen. (June 1999) Oregon Road/Stream

Crossing Restoration Guide, Advanced Fish Passage Training Version.

www.nwr.noaa.gov/1salmon/salmesa/4ddocs/orfishps.htm.

28
Stream Systems Technology Center, Rocky Mountain Forest and Range

Experiment Station, USDA-Forest Service. A Guide to Field Identification

of Bankfull Stage in the Western United States. (video) www.stream.fs.fed.us.

Taylor, R. N., and Michael Love (August 2001) Fish Passage Evaluation at

Stream Crossings. Prepared for California Dept of Fish and Game.

USDA—FS. (1998) WinXSPRO, A Channel Cross Section Analyzer, User’s

Manual. Prepared by West Consultants Inc. USDA—FS Rocky Mountain

Experiment Station, Ft. Collins, CO.

USDA Forest Service. (1999) Roads Analysis: Informing Decisions about

Managing the National Forest Transportation System. Misc. Report FS-643.

Washington, DC. USDA Forest Service. 222 p.

USDA Forest Service, Region 6. Fish Passage through Road Crossings

Assessment, with Explanations and Instructions. Unpublished report

available through the USDA Forest Service Region 6 regional office.

USDA Forest Service, Region 10. (March 2001) Forest Service Handbook

7709.58—Transportation system maintenance handbook. Region 10,

Supplement No. 7709.58-2000-1.

USDA Forest Service, Region 10. Tongass Fish Passage Protocol (Riparian

Monitoring Question #3. Unpublished report available through the USDA

Forest Service Region 10 regional office.

Warren, M. L., Jr, and M.G. Pardew. (1998) Road Crossings as Barriers to

Small Stream Fish Movement in Trans Am Fisheries Soc 127:637-644.

Washington Dept of Fish and Wildlife Habitat Program, SSHEAR section.

(August 2000) Fish Passage Barrier and Surface Water Diversion Screening

Assessment and Prioritization Manual. http://www.wa.gov/wdfw/hab/

engineer/fishbarr.htm.

29
EXAMPLE SCHEME FOR SETTING

PRIORITIES— MODIFIED FROM THE

CALIFORNIA METHOD

APPENDIX A

This ranking method is slightly generalized from a draft developed for California

by Taylor and Love (2002); it is shown here with their permission. The

original was devised primarily for coastal watersheds with potential habitat

for anadromous salmonids. Some terminology has been modified to be

consistent with this document, the emphasis on anadromous fish has been

eliminated, and the extent-of-barrier variable has been simplified (2, below).

The ranking method assigns scores for the following parameters at each

barrier crossing.

For each road crossing, add up ESA-listing status scores for each species

known to be within the stream reach (now or historically). Score:

Endangered = 3 points; Threatened = 2 points; not listed = 1 point Consult

your local State Fish and Wildlife agency, USFWS, or NMFS for species

distribution and listing status.

For each species and lifestage of concern at the crossing, determine

whether it is a total or partial (passable at some flows) barrier. Add the

scores to get a total barrier extent score. Score: Total barrier for a species

and lifestage= 2 points; partial barrier for a species and lifestage=1 point.

Score length in feet or meters above the road crossing to the limit of

distribution of the analysis species. Score: We suggest starting at some

agreed on minimum (such as, 500 ft); and assign 0.5 points for each size

class unit (example: 0 points for <500 ft; 1 point for 1,000 ft; 2 points for

2,000 ft; and 5.5 points for 5,500 ft).

Assign a habitat-quality score after reviewing available habitat information

as follows.

• Score: 1.0 = Excellent. Relatively undeveloped, “pristine” watershed

conditions. Habitat features include dense riparian zones with mix of

mature native species, frequent pools, high-quality spawning areas,

high water quality, near natural water temperature regimes, complex

in-channel habitat, channel floodplain relatively intact. High likelihood

of no future human development. Presence of one or more migration

barriers is obviously the watershed’s limiting factor.

• 0.75 = Good. Habitat is fairly intact, but human activities have altered

the watershed, and that activity is likely to continue. Habitat still

includes dense riparian zones of native species, frequent pools, spawning

1. Species diversity

2. Extent of Barrier

3. Habitat quantity

4. Habitat quality

30
gravels, good water quality, near- natural water temperature regimes,

complex in-channel habitat, floodplain relatively intact. Presence of

one or more migration barriers is most likely one of the watershed’s

primary limiting factors.

• 0.5 = Fair. Human activities have altered the watershed. Expect continued

or increased human activity that will continue to affect watershed

processes and features. Habitat effects include riparian zone present

that lacks mature vegetation and has non-native species, infrequent

pools, sedimentation evident in spawning areas (pool tails and riffle

crests). Water quality and water temperature regimes have been altered

to the point that they periodically exceed stressful levels for analysis

species. There is sparse in-channel complex habitat, floodplain intact

or slightly modified. Presence of one or more migration barrier is probably

one of the watershed’s limiting factors (out of several factors).

• 0.25 = Poor. Human activities have significantly altered the watershed

with high likelihood of continued (or increased) activities, with apparent

effects to watershed processes. Habitat effects include intact riparian

zones absent or severely degraded, little or no pool formations, excessive

sedimentation evident in spawning areas (pool tails and riffle crests),

water-quality problems are stressful to lethal to analysis species, lack

of in-channel habitat, floodplain severely modified with levees, riprap,

and residential or commercial development. Other limiting factors in

watershed most likely have higher priority for restoration than

remediation of migration barriers.

Multiply the scores for habitat quality and habitat quantity for each blocked

species of concern. Add all the species together to get the total score.

Score each culvert according to the size of flow it was designed to accommodate.

Score: sized for at least a 100-year flow at headwater/depth = 1, low risk = 1;

sized for at least a 50-year flow = 2; sized for at least a 25-year flow = 3;

sized for less than a 25-year flow = 4; sized for less than a 10-year flow = 5.

for each culvert, assign one of the following values. Score: good condition = 1;

fair (problems exist but are not likely to cause culvert to fail) = 2;

poor (problems could cause failure) = 3.

For each road crossing, enter the scores into a spreadsheet and compute

the total. Then, sort the list by “total score” to determine a first-cut ranking.

Other sorts can be done to isolate certain kinds of crossing problems. For

example, sites that have poor habitat quality may be sorted separately so

that ranking at these sites can focus on culvert sizing and risk failure.

The results of the ranking matrix provide a rough, first-cut prioritized list

of crossings requiring treatment. Other important factors will be considered

when you decide the exact scheduling of remediation efforts.

5. Total habitat score

6. Sizing (risk

of failure)

7. Current condition

Additional Ranking

Considerations

31
On a site-specific basis, some or all of the following factors should be

considered in refining the first-cut ranking.

1. Amount of road fill. At structures that are undersized or in poor

condition, consider the volume of fill material in the road prism

potentially deliverable to the stream channel if the culvert were to fail.

Also consider diversion potential.

2. Presence or absence of other road crossings. Multiple roads under a

variety of management or ownership may cross a single stream. Then,

close communication with other road managers is important. If

multiple culverts are migration barriers, a coordinated effort is required

to identify and treat them in a logical sequence.

3. Presence of aquatic organisms attempting to migrate past a barrier.

In Northern California, several crossings were ranked higher because

of the annual presence of adult salmonids below total barriers. After

treatments, the upstream habitat was immediately recolonized the

following winter.

4. Remediation project cost. You should examine the range of treatment

options and associated costs when determining the order in which to

proceed and what should be implemented at specific sites. Where

federally listed fish species are present, costs must also be weighed

against the consequences of failing to comply with the ESA by not

providing unimpeded passage.

Other limiting factors. Other limiting factors besides migration barriers often

exist in a watershed and limit production of aquatic species. On a watershed

or sub-basin scale, restoration decisions must be made after carefully

reviewing potential limiting factors, the source of the effects, range of restoration

options available, and what restoration activities are actually feasible.

32
Fill-in-the-Blank Regional Screen,

California model

APPENDIX B

Calculate: average active channel width, culvert slope,

residual depth at inlet, and drop at outlet

Streambed substrate

throughout culvert

Inlet width >

bankfull width

No outlet drop and

residual inlet depth

>___1

No outlet drop and

residual inlet depth

> ___1

outlet drop > ___2

outlet drop > ___2 Slope > ___3 and

contains no

baffles/weirs

Culvert contains

baffles/weirs for

fish passage

outlet drop < ___2

and Slope < ___3

Indeterminate using

regional criteria—go

to hydraulic model to hydraulic model

Passage

conditions

inadequate

Passage

conditions

adequate

Resembles Natural Resembles Natural

Channel Channel

Passage conditions

adequate

Passage

conditions

adequate

Passage

conditions

inadequate

Indeterminate using

regional criteria or model regional criteria or model

(Fishxing)—monitoring

required

Indeterminate using

regional criteria—go to

hydraulic model—Passage

may not be adequate

YES

YES

YES

YES

YES

YES

YES

YES

NO

NO

NO

NO

NO

NO

NO

NO

1 The low flow depth required to allow passage of the analysis species.

2 The jump height of the analysis species.

3 The culvert slope above which the analysis species cannot pass.

Note: Values 1-3 are to be developed regionally in cooperation with resource

management

Passage inadequate: Crossing does not meet the criteria for the analysis species for which the screen is designed.

Indeterminate barrier category: for analysis species using the screen.

33
34

Alaska Washington Oregon NMFS SW Region California Dept NMFS NW Region Idaho

Fish & Game (draft salmonid

guidelines)

Q50 or Q 100

Q100 with debris Q100

Q100 at Q100 at

headwater/depth = 1 headwater/depth

= 1.5

“Q2d2”: the 10% exceedance 10% for adult salmon & standards vary 5% exceedance flow < 2-day delay

discharge flow during exceedance steelhead 1% annual from 1%-10% for period of during period

24 hours migration period: flow during exceedance flow or annual exceedance upstream migration of migration

before or species-specific migration 50% Q2. For juveniles, for various groups

after the period: 10% annual of fish

2-yr flood species- exceedance flow

specific.

Approximate

by Q10% =

0.18*(Q2)+36

where

Q2 > 44 cfs.

Where

Q2 < 44 cfs,

use Q2.

None 2-yr, 7-day low 2-yr, 7-day for adult salmon & standards vary 95% exceedance

flow low flow or steelhead, the greater from 50%-95% flow during months

95% of 3 cfs or 50% annual annual exceedance of upstream migration

exceedance exceedance flow. for various groups

flow for For juveniles, the of fish

migration greater of 95% annual

period: exceedance flow or

species- 1 cfs

specific

STATE AND AGENCY GUIDELINES FOR FISH PASSAGE FLOWS

High Flow Capacity (crossing must pass this flow, but fish passage is not required)

High Fish Passage Flow

Low Fish Passage Flow

APPENDIX C Hydrology and flow requirements Several states have defined flows at which fish passage should be provided. Except for Alaska and Idaho, these requirements apply only to hydraulic designs (not stream simulation).

Q100 means the peak flow equaled or exceeded on average once in 100 years. Determined based on annual peak flow data set.

10% exceedance flow during the migration period means the daily average flow that is equaled or exceeded 10% of the days in the period the

selected fish species are moving. That period is usually established by the state fish and wildlife management agency. Based on period of record

daily-flow data set for the migration period.

1% annual exceedance flow means the daily average flow that is equaled or exceeded 1% of the days of the year. Determined based on period of

record daily mean flow data set for the entire year.
Example Job Hazard Analysis from

Umatilla NF

APPENDIX D

JHA provided courtesy of John Sanchez, Umatilla NF

The Occupational Safety and Health Administration has requirements

related to working in confined spaces [Safety training and Education –

1926.21(b)(6)(i)]. These requirements can be found at their website:

www.osha.gov/pls/oshaweb.

U.S. Department of Agriculture

Forest Service

JOB HAZARD ANALYSIS (JHA)

References-FSH 6709.11 and -12

(Instructions on Reverse)

1. WORK PROJECT/ 2. LOCATION 3. UNIT

 ACTIVITY UMATILLA NATIONAL R6-14

FISH PASSAGE FOREST

CULVERT ASSESSMENT

JUNE/SEPT 2001

4. NAME OF ANALYST 5. JOB TITLE 6. DATE PREPARED

 J.SANCHEZ FISH BIOLOGIST 05/25/2001

7. TASKS/PROCEDURES 8. HAZARDS 9. ABATEMENT ACTIONS

 Engineering Controls * Substitution *

 Administrative Controls * PPE

* Driving on main roads as well

as 4wd and other secondatry

roads which are heavily used

by public, working long days

*working in roadway and

crossing the road

*climbing up/down banks,

over rock and loose fill in

wading boots

*walking in culverts and in

streams in wading boots

*potential for heavy

traffic/fast vehicles;

uneven roads; atv and

bike use by recreationists;

being tired while driving/

lack of concentration on

tasks /mental and

physical errors

*high traffic volume on

main roads; sites close to

bends in roadway

decreasing visibility

*poor foot traction in

wading boots; easy to

slip and fall; kicking

loose rocks down onto

workers below

*culverts and rocks are

slippery when wet and

covered with algae;

uneven surfaces in

culverts and streams;

strong flow

*follow safe and defensive driving practices;

take rest breaks as needed; change drivers as

needed

*watch for traffic and check both directions

before crossing; post a lookout if needed;

use caution especially at sites close to bends

in the road. Wear hard hats and safety vests

to increase crew visibility to oncoming drivers

* look for safest way down bank; don’t rush;

use a pole to help balance; make sure others

are not directly below you as you climb up or

down the bank

*don’t rush; wear wading boots with felt

bottoms; use a wading staff for support; be

confident of your footing before taking next

step in fast moving water

35
7. TASKS/PROCEDURES 8. HAZARDS 9. ABATEMENT ACTIONS

 Engineering Controls * Substitution *

 Administrative Controls * PPE

*climbing over/under/around

timber and walking over

uneven terrain and over

vegetation covered ground in

wading boots

*working outside in weather

(heat/rain/cold/snow/thunder

and lightning)

*working outside-encounters

with snakes, bees, wasps,

biting flies etc

*conduct tailgate safety

meetings as needed

*use proper department check

in / check out procedures

*driving an all-terrain vehicle

on forest roads

* logs are slick when wet;

hard to see the ground;

unstable snags may fall;

debris piles may be

unstable; twisted ankles;

snagging waders on

limbs and fences

*dehydration; hyper and

hypothermia; threat of

storms

*allergic reations such as

anaphylactic shock/

rash/swelling etc

*

* find safest and easiest route around logs; go

around or under instead of over; step

cautiously on piles of debris; identify

unstable snags and stay clear; use rod to

help find stable/unstable spots

*drink plenty of water; dress appropriately for

weather; monitor weather reports; carry a

radio and extra batteries; keep dry clothes in

vehicle.

*identify all crew member’s allergies and

inform all crew of potential health problems;

always carry a first aid kit equipped with

antihistamines/epi pin/benadryl as

necessary in vehicle and in packs; discuss

first aid techniques and training for all crew

members as needed

*follow safe operating procedures for atv;

wear all appropriate safety gear (helmut,

gloves, boots, long pants and long sleeved

shirt); maintain safe and proper speed; scan

ahead for hazards; keep all items strapped

down tightly to avoid unexpected shifting of

weight; carry a radio and 1st aid kit in case of

emergency

10. LINE OFFICER SIGNATURE 11. TITLE 12. DATE

Previous edition is obsolete (over)

36
Explanations and Instructions for

Passage Through Road/Stream

Crossings Inventory Form

APPENDIX E

These instructions accompany the Passage Through Crossings Assessment

forms. The inventory collects information required to assess passage of fish

and other animals through crossing structures on both roads and trails.

The procedure does not handle bridges because most often these structures

do not obstruct aquatic organisms. The data sheet can be modified if need

be for field convenience. However, it is critical to preserve the definitions of

the variables and the methods of measurement prescribed in this document.

New database structures are being modeled now for storage of this data in

Forest Service Infrastructure database (INFRA) and Natural Resources

information system (NRIS).

Once the field data have been collected, a passage assessment is made in

the field. First, determine whether the crossing resembles the adjacent

natural channel. If it does, we assume it passes most organisms. The criteria

for making this determination are listed under “Field Passage Evaluation”

in these instructions. Second, if the crossing does not resemble the stream

channel, then use the regionally developed species, lifestage, or species

group-specific criteria to determine whether the structure’s passage

conditions are adequate, inadequate or are indeterminate.

If you cannot determine whether the crossing is a barrier, and the analysis

species is a fish for which swim performance information is available, then

hydraulic analysis using FishXing can be conducted for many types of

crossings. The FishXing software is available on the web at: http://

www.stream.fs.fed.us/fishxing. See instructions and help files prior to

running the program.

In addition to the information collected through this inventory the

following inputs are also needed to run FishXing:

• Hydrologic criteria, including low passage flow and high passage flow.

• Fish information, including swimming capabilities and depth requirements.

Although the field assessment form is designed primarily for culverts, fords

can also be inventoried. Instructions for taking measurements on fords are

included. The survey measurements can support limited open channel flow

analysis, but passage assessments on fords are usually a matter of directly

observing animal passage. In these cases, more than a single visit may be

needed to adequately assess their passage. Other complex installations

difficult to model hydraulically, such as baffled culverts, may also require

multiple visits.

37
38

Data elements in bold are required for Forest Service Infrastructure database (INFRA)/

Natural Resource Information System (NRIS) or are needed to evaluate passage at the 

crossing. Other data are useful for prioritizing culvert restoration, developing pre-project budget cost estimates, or to field check flow estimates used in FishXing analyses.

The last page of the form (p 69h) is not intended for field use. Its purpose is to document biological and watershed context information about the site that is critical to 

complete the permanent file, and for replacement project prioritization. Usually this 

form will be filled out in the office, before or after the survey.

A supplemental form is attached for sites where there are more than one pipe or box. 

In most cases, where there are several pipes in close proximity, only part of this form 

will be needed. However the complete survey pages are included for cases where side 

channel culverts are being evaluated separately for passage conditions.

Some of this information can be collected in the office before beginning the field portion of the assessment.

Each crossing location should be clearly marked on the best available map, preferably 

an 8.5 by 11, 1:1 scale photocopy of a USGS 7.5-min. topographic quadrangle. Each 

map sheet should be labeled with the crossing identification number to help eliminate 

confusion both during the inventory and when crossing data are linked to GIS coverages.

If the culvert installation is already entered in INFRA, use the control number of the 

culvert installation as the crossing site ID number. Otherwise, this can be any number 

that uniquely identifies each crossing. It should be entered on each a page of the field 

form, and it should be used on photograph and map labels.

Where there is only one pipe at a crossing site, the single pipe will be identified as 

“Structure 1 of 1” and the structure milepost is the site milepost. For crossings with 

more than one pipe or opening, the crossing ID number identifies the site as a whole, 

and the individual pipes are numbered “structure 1 of __, structure 2 of __, etc. starting 

with the pipe closest to the beginning of the road (milepost 0). The principal structure—generally the lowest elevation since that will carry the lowest flows—is described on the main data sheet “Passage through Crossings Assessment.” Supplemental 

data sheets with the same crossing ID number are used to describe pipes other than the 

principal structure. Each additional pipe is described on a separate supplemental form, 

and its milepost is entered as ʻstructure milepostʼ on that form. (See further explanation under Route number and INFRA Milepost.)

If a site has two or more structures (pipe or box) of the same size, materials, elevation, 

and orientation, measurements are needed only on whichever structure is identified 

as the principal one. This will be the pipe that conveys most flow. Note the number of 

other identical openings and their mileposts in the multiple structures box (see Figure 

E-1). Use the sketch to describe the accompanying culverts; also take photos. Each 

pipe will be entered in INFRA separately.

Site

Crossing site 

identification 

number box

Multiple structures 

at one site 

Line-by-Line Instructions
39

If a site has two or more structures (not including overfl ow pipes) that are not the 

same (i.e., they have different dimensions, elevations, shapes, etc), complete a supplemental form for each additional structure. Complete the main form for the principal 

structure, and in the multiple structures box indicate that one or more supplemental 

forms were fi lled out for this site (see Figure E-1).

Many sites have ʻoverfl owʼ culverts to convey high fl ows that exceed the capacity of 

the principal structure. As shown on Fig. E-1, some are simply above the main culvert. 

If one of your objectives is to determine site peak fl ow capacity, then all the “crossing 

structure” as well as slope data (pages 1 and 2) are needed for this kind of pipe. Since 

all pipes are entered separately into INFRA, you should complete the supplemental 

data sheets for them unless they are already in the database. If you do not need the 

individual pipe data, simply note the number and mileposts of the overfl ow culverts 

in the multiple structures box (___ number of overfl ow pipe(s), no supplemental 

forms”) and include them in sketches and photos.

Sometimes determining what the “site” is will be diffi cult—where a very wide fl oodplain has relief culverts for fl ood fl ows under the road, for example. In deciding how 

to handle such crossings, consider how the site hydrology will be developed. Where 

pipes are on the fl oodplain of a single channel, consider lumping them into a single 

crossing site. Some fl oodplain pipes are on side channels that also require passage 

assessments. The supplemental fi eld form includes pages (4-6) for channel data that 

would be needed to compare the side channel culvert to the natural side channel. The 

surveys for the main pipe and fl oodplain pipes should be tied together using the same 

control points. Be sure to describe the relationships in the comments section. 

Note that pages 4-6 in the multiple structures supplemental form will not be needed 

except for unusual situations, such as side channel culverts where passage is required. 

Pages 1-3 should be fi lled out for all structures.

Figure E-1. Multiple structures at one site.

Road surface

Crossing ID number_______________________

Structure_________of__________

Structure milepost same as site milepost

 Multiple structures at site:

_____# identical openings

Mileposts_____________________

_____# different openings with forms completed

_____# overflow pipes no supplemental forms

completed Mileposts_____________________

mp 1.000 _____# overflow pipes with forms completed

To beginning of road

mp 1.002

mp 1.004

2 identical cirrcular culverts

Note: In this case INFRA milepost for the site is mp 1.000.

Overflow pipe

Fillslope

Route number:_______ INFRA 142 Milepost:________

1

1

1.002

1

3

1.000

Hat 03
40

Record the road or trail number, and the site INFRA milepost, if known. If the installation is not entered in INFRA yet, measure the mileage from the beginning of the route 

to the center of the first (or only) pipe in the installation (see Road User Board Meeting 

Notes, Redding CA, 4-2002). The milepost of the first pipe in a multiple-structure 

installation is always the site milepost.

The supplemental forms (for structure 2 of X, etc.) do not include site milepost, since 

the site is identified by the crossing ID. Other structure mileposts are entered on the 

supplemental sheets in the crossing ID box. Mileposts for different structures at the 

same site should be recorded in 1/1000ths of a mile (for example, culvert 1 = MP

1.000, culvert 2 = MP 1.001).

Where available, use a distance measuring instrument (DMI) attached to the vehicle 

for accuracy. For more information see http://www.nu-metrics.com. Click on NITESTAR on left column. Approximate cost is around $150-$250 for unit, installation 

kit, and installation.

Driving from the beginning of the route to the crossing site is the most direct and accurate way to get the INFRA milepost. Be aware that if you access the site by another—

perhaps shorter—route it may be difficult to accurately locate the site later. If you do 

take a different road to the site, record the mileage from a clearly identifiable junction 

on the road you actually drove (for example, 1.5 miles from intersection of road 123 

with road 145). Be sure to take a GPS reading at the crossing.

For non-Forest Service land, substitute appropriate administrative units.

Enter the hydrologic unit code (HUC) number of the watershed or sub-watershed. Use 

the 6th-field HUC where possible.

Get the stream name from USGS 7.5-minute quad or other local sources. If a crossing 

is on an unnamed stream that is a tributary of a larger sub-basin in a major basin, include all named sub-basins. For example: unnamed, tributary to Davis Creek, tributary 

to Outlet Creek, tributary to South Fork Eel River, Eel River watershed.

Input the USGS quadrangle name, the land ownership or jurisdiction, the legal description (township, range, section), and principal meridian.

Record the X and Y coordinates from the GPS unit for permanent site identification, 

along with the datum (eg., NAD27). If you use something other than latitude and longitude, note the coordinate system and zone.

Record the surveyorsʼ names.

Enter the date the field data are collected. 

Route number and 

(INFRA) milepost 

(office or field determination)

Milepost from junction 

of road number 

(field determination)

Forest and district

Watershed 

(office determination)

Stream name 

(office determination)

USGS topographic 

quad name, 

ownership, and legal 

description

Global positioning 

system location

Surveyors

Field date
41

Choose appropriate type of culvert or ford, and measure dimensions. Depicted below 

are the barrel cross-sections of common culvert types that can be modeled in FishXing.

Figure E-2. Common culvert shapes.

Log culverts, “Humboldt” crossings (porous structure made of stacked logs), irrigation diversion structures, and other less common crossings are described under “other”. For analysis in FishXing, select the shape from the four above that most closely 

resembles the observed pipe, using as criteria similar cross-section area and wetted perimeter at passage flows. Other culvert shapes should be described in enough detail to 

permit determination of pipe capacity from information provided by the manufacturer 

or from other sources.

Ford Types

The two types of low-water fords are unvented (Figure E-3) and vented (Figure E-4). 

At unvented fords, traffic drives through the stream until increasing flows cause the 

water to become too deep to traverse. Unvented concrete fords are often barriers to 

fish passage at low flows because of the shallow flow depth. Some of these have slots 

of various sizes, with or without grated coverings that may allow fish and amphibian 

passage.

A vented ford includes a low-flow conveyance structure such as a culvert, so that traffic does not travel through the water at low flows. Only at moderate or high flows is 

the vented ford submerged. The many designs of vented fords include:

 • A single pipe or box;

 • Multiple round or box culverts that are essentially identical; and

 • Multiple round or box culverts with one pipe designed to capture all of the 

 low flow.

In vented fords the vent is described as a culvert for the inventory, and the ford dimensions in Figure E-4 (F1, F2, and sag) are also measured. Check both structure shapes 

on the form. True fords, where vehicles cross at streambed elevation, are “fords”, 

whether or not they have a slot for aquatic organism passage.

Crossing structure

shape

Circular

��������

Pipe Arch

����

����

Open-bottom Arch

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����

Box

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42

Figure E-3. Low water ford (unvented)

Figure E-4. Low water ford (vented)

Record the maximum width (span or diameter measured horizontally) and the height 

(rise or diameter measured vertically) of the culvert, measured from the inside of the 

corrugations.

• Circular culverts and pipe arches. Measure both height and width. Pipes are 

often distorted during and after installation.

• Open-bottom arches. For open-bottom arches, measure the width of the pipe 

from metal to metal, not from foundation to foundation, unless the streambed 

is scoured to below the top of the foundation. Then, also measure flow width 

between foundations and the depth of scour below the top of the foundation at 

top and bottom of the pipe (in FishXing this configuration may be modeled as a 

flat-floored rectangular box). Measure the height of the pipe from the streambed to the top of the culvert.

• Embedded pipes. If possible, dig or probe to find the depth of substrate at the 

inlet and add that to the height measured from the bed to the pipe top. If that 

is not feasible, culvert height can be estimated from width for standard pipe 

shapes (see AISI 1994 or FishXing). Many structures are manufactured that do 

not conform to “standard” dimensions, so it is advisable to measure substrate 

depth directly.

��

��

����

������� �������������

���������

Culvert dimensions

F1

Road

Sag or Height

F2
43

Ford Dimensions – optional data

Aside from the standard culvert or box data on the vents in vented fords, ford dimensions only need to be measured if average flow velocities and/or peak flow capacity 

estimates are desired. FishXing cannot be used for fords during overflow conditions. 

Open-channel flow equations (e.g., Manningʼs) or weir equations can be used to make 

velocity and depth estimates where the assumptions specific to each equation are met. 

Three measurements are needed to describe the shape of any ford. 

• F1 is the width (horizontal distance measured parallel to the road) of the top of 

the ford; that is, between the points on the road at which the roadway transitions out of its vertical curve (see Fig. E-3). This measurement helps determine 

the structureʼs peak flow capacity.

• F2 is the width (horizontal distance measured parallel to the road) of the bottom of the ford. Low-flow depths across the ford will be determined by this 

width.

• Sag or Height – The vertical difference in elevation between the bottom of the 

ford and the elevation of the roadway if it were projected across the ford.

Some unvented fords have slots to accommodate fish or amphibian passage during 

low flows. The dimensions of the slot should be noted and its slope and any perch 

should be measured during the survey (see The Survey, below).

Rust line

If the culvert is made of steel it will have a rust line. Measure the height of the rust 

line above the culvert bottom away from noticeable elevation changes near the inlet or 

at obstructions. The rust line indicates a persistent high flow. The actual exceedance 

value or recurrence interval of this flow is expected to vary across the country depending on the local streamflow regime.

If the culvert material does not fall into one of the following categories, give a brief 

description characterizing its roughness.

• Corrugated metal pipes (CMP) are constructed from single sheets of corrugated metal. Spiral culverts have helical corrugations, reducing the culvert 

roughness. Annular culverts have concentric corrugations.

 * Steel = corrugated steel, may show rust line.

 * Aluminum = corrugated aluminum, no rust line.

• Structural plate pipes are constructed of multiple plates of corrugated galvanized steel or aluminum bolted together. They always have annular corrugations.

• Plastic may or may not have corrugations.

• Concrete is used in many box and some circular and arch culverts.

• Wood and logs are used to make log stringers, log box culverts, and circular 

culverts.

Ford surfaces also vary, ranging from natural stream bottom with no improvements 

to paved road surfacing. The surface designs of most concern for animal passage are 

those that are smooth; these surfaces tend to reduce water depths at low flows and 

increase velocities at high flows. In addition, high water velocities across smooth ford 

Structural material
44

surfaces cause scour of the natural streambed downstream, usually creating a perch at 

the outlet of the ford. In ford surface materials under “other” write in natural streambed, asphalt, geotextile/gravel, concrete, pit run, or other rock.

Figure E-5. Measuring corrugations.

Measure the width and depth of the corrugations in inches (see Figure E-5). Most CMP

under 60 inches in diameter have 2 2/3-inch x 1/2-inch corrugations. CMP greater than 

or equal to 60 inches in diameter typically have 3-inch x 1-inch corrugations. Structural plate pipes (SPP) and structural plate pipe arches (SPPA) often have 6-inch x 2-inch 

corrugations. The size of the corrugations determines the culvert roughness, which is 

used in FishXing. Corrugations are measured from crest to crest (width) and valley to 

crest (depth). Measure them in areas without deformation

Mark all inlet descriptions that fit (see Figure E-6). The culvert inlet type determines 

the headloss coefficient at the inlet of the pipe. This coefficient is a measure of the energy loss as water enters the pipe, and is required for the hydraulic analysis performed 

in FishXing.

Figure E-6. (from Normann et al 2001). Inlet type examples (clockwise from top left): 

projecting, headwall and wingwall, mitered and metal or cement end section. Wingwall measurement is illustrated here.

Corrugations

Inlet type

������

�����

����������������������

���������

����

����

������

�����������
45

Many inlet types are not included either here or in the FishXing defaults. See Normann and others (1985) for head loss coefficients associated with several other types. 

Also use “other” for drop inlets, beaver excluders, and so on.

Measure the angle (<90 degrees) between the road centerline and a line perpendicular 

to the culvert centerline (Figure E-7). This measurement is required in INFRA. It is 

not directly relevant to aquatic species passage, although it is related to culvert length 

(the shortest culvert is not skewed; ie. it is perpendicular to the road). Alignment between the pipe inlet and the upstream channel is important to aquatic species passage. 

It should be documented on the site sketch, as discussed in section Site Sketch.

Figure E-7. Measurement of culvert skew.

Check the best description of culvert outlet configuration (see Figure E-8). Also use 

these descriptors for the downstream edges of fords.

• At streambed elevation—No perch at the outlet.

• Cascade over riprap—Culvert outlet flows onto either a rough riprap surface 

causing turbulence or a riprap or bedrock surface where flow depth decreases 

as it exits the culvert.

• Freefall into pool—Culvert outlet is perched directly over a pool. Requires 

migrating fish to jump into culvert from outlet pool.

• Freefall onto riprap—Culvert outlet is perched and exiting water plunges 

onto riprap or bedrock with no pool.

• Outlet apron—Aprons are usually made of concrete or riprap and installed to 

prevent or reduce scour. If an apron exists, provide brief a description, including any low-flow concentration structures (such as curbs), and include a site 

sketch.

Skew

Outlet configuration

����������

����

������
46

Figure E-8. Outlet types.

Outlet Types

Outlet drop

or perch.

E8c—Freefall into pool

E8b—Cascade over riprap

E8d—Freefall onto riprap

E8a—At streambed elevation

E8e—Onto outlet apron
47

If the culvert contains baffles, weirs, boulders embedded in concrete, or other fabricated structures inside the culvert, give a brief description. Because baffle designs 

are often not standardized, a sketch with detailed dimensions is needed. Describe the 

structuresʼ location in the pipe, materials, spacing, height, and configuration. Also 

describe any notch shapes, dimensions, and arrangement.

Identify problems that could cause the culvert to plug or fail and affect resources. 

Check any of the observed conditions or note any not listed.

• Breaks in slope inside of culvert: Make sure they are actual breaks and not 

just debris build up. If removing the debris would eliminate the break, it is not 

a slope break. Estimate horizontal distance to the break from the outlet and 

estimate the vertical difference.

• Debris plugging inlet (estimate the percentage of inlet that is blocked)

• Fill eroding

• Bent inlet

• Debris plugging inlet

• Bottom worn through

• Debris in culvert

• Water flowing under culvert

• Other (such as, streambed scouring between open-bottom arch foundations)

Many of these elements can also be used to describe unvented fords. Other observations pertaining to fords might be: surface cracked (for concrete or asphalt), water 

running around edge of ford, ford surface rutted, toe of fill undermined, and so on.

Briefly describe the condition of functioning or needed BMPs such as fillslope vegetation or other erosion controls, downstream grade controls, etc. Show problems in a 

sketch and photographs.

This is one of the factors influencing the magnitude damage to the stream and road if 

the crossing should fail. Most decision makers will consider this as they decide which 

crossings should be replaced first. Streams can be diverted at crossings if the road 

has “a continuous climbing grade across the stream crossing or where the road slopes 

downward away from a stream crossing in at least one direction” (Flanagan and others 

1998). For a full description of diversion potential assessment please read Flanagan 

and others (1998) available on the web at: http://www.stream.fs.fed.us/waterroad/ w-rpdf/diversionpntl.pdf.

These data are optional in INFRA. These measurements are intended to define the 

prism of soil that would:

1. be removed to reconstruct the crossing (a major component of replacement 

cost) or

2. be eroded during crossing failure causing potential harm to downstream habitat.

Baffles and weirs

Pipe condition

Diversion potential—

(optional data for 

prioritization)

Fill volume estimate—

(optional data for 

prioritization and cost 

estimates)
48

This method is taken directly from Flanagan and others (1998), and is meant to generate rough volumes for site comparison during project prioritization. The measurements 

are also commonly used for project budget cost estimates. However, they can contain 

signifi cant error and are not adequate for contract development.

Measure or estimate the following:

• Lu and Ld: Upstream and downstream fi llslope lengths. Note that Ld often 

extends below the culvert outlet.

• Su and Sd: Slope (percent) of upstream and downstream fi llslopes.

• Wr: Width of road.

• Wf: Length of road on fi ll. Measure the road from start to end of fi ll wedge 

(along the road alignment). At these points, the roadbed transitions from roadcut or natural ground to fi ll material.

• Wc: length of fi ll at bottom of fi ll wedge.

Wf and Wc are intended to be the dimensions of fi ll that would be removed during 

reconstruction or by crossing failure. If the fi ll is extremely long (as for example in 

a very wide valley), estimate these dimensions. In a case like this, the data analyst 

will have to exercise judgment to determine the appropriate lengths to use for the fi ll 

volume calculation.

Figure E-9. Fill volume measurements

Wr

Sd(°) Su(°)

Hu Hd

Ld

Lu

Bd

Bu

CL

Flow

Slope(°)=arctan( )

Flow

Cross-section

Side view

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Slope %

100
49

Crossing fill measurements—solid lines are measured values; dashed lines are calculated. Note that Ld often extends below the culvert outlet (Flanagan et al 1998).

Use the following equations to estimate total fill volume within the channel. Note that 

slope is in units of degrees. To convert slope percent to degrees, divide percent slope 

by 100 and take the arctangent.

1. Vu = 0.25 (Wf + Wc)(Lu cos Su)(Lu sin Su) Upstream fill prism

2. Vd = 0.25 (Wf + Wc)(Ld cos Sd)(Ld sin Sd) Downstream fill prism

3. Vr = (Hu +Hd) • (Wf + Wc) • Wr where Hu = Lu sin Su

 2 2 Hd = Ld sin Sd

4. Total fill volume = Vu + Vd + Vr

Survey a longitudinal profile at each crossing, using a surveyorsʼ level to provide 

elevation data accurate enough for passage analyses. A clinometer does not have the 

accuracy needed for evaluating passage. At sites without vehicular access, a hand 

level mounted on a rod of known elevation may be considered for steeper culverts. 

Be aware that hand level readings are generally not reliable enough where a hydraulic 

analysis will be needed. Even if the structure is so short that the entire profile is within 

sight distance as viewed through a hand level, holding it at exactly the same elevation 

throughout is very difficult. You may be tempted to accept readings of marginal accuracy, but small inaccuracies can make large differences in a hydraulic analysis. If a 

hand level is used, be sure to state that in the notes, to help explain any data discrepancies discovered during data processing or quality checks.

To start the survey, determine the starting point by looking at the channel upstream of 

the inlet. Ideally, the starting point is the tailwater control for the first upstream holding habitat for a fish exiting the crossing structure (see Figure E-12). If no such feature 

is obvious, select the starting point to include any potentially adverse exit conditions 

(such as a steep slope near the crossing inlet).

Place a 300-foot tape down the approximate center of the stream channel. Set the tape 

to reflect any major changes in channel direction (note “lay of tape” on site sketch). 

Continue setting the tape through the structure and downstream to a point below the 

tailwater control of the pool at the structure outlet. The tailwater is the structure (artificial or natural) that controls the water surface elevation at the outlet of the culvert. 

Tailwater controls can be riffle crests, weir crests, and natural channel constrictions. 

If several stair-stepped pools lead up to the outlet, set the tape to the riffle crest of the 

lower-most pool.

Be very careful wading through culverts. In older corrugated steel culverts check the 

floor carefully for rusted-through areas or jagged edges. A hardhat and flashlight are 

recommended items for crewmembers setting the tape and holding the rod. Where 

entering the structure it is not feasible, such as at small diameter or severely rusted 

culverts, try floating the tape down through the culvert. Otherwise, measure structure 

length as accurately as possible from the road surface. Make note of these measurements and attempt to verify length from existing road databases or from as-built plans.

Set the level to eliminate or minimize the number of times it must be moved to complete the survey. Usually, the road surface is optimal, allowing a complete survey to 

be shot from a single location. At sites with high road prisms or with breaks-in-slope 

in the structure, however, the best place for the level may be in the stream channel. To 

The long profile 

survey (modified from 

Taylor and Love, 2002)
50

survey the longitudinal profile, place the rod at the thalweg at various stations along 

the center tape, capturing noticeable breaks in slope along the stream channel.

Tie all surveyed points, including multiple structures, to a common immovable datum 

or temporary benchmark. The center of the culvert inlet bottom (invert) is often used, 

but any point that can be reoccupied in the future will suffice to establish the benchmark elevation. Where the structure is embedded, the top of the inlet or a point on the 

road surface can be used. Clearly mark the spot so that elevations can be checked if the 

level is moved or jarred during the survey, and show the spot on the site sketch. Commonly, an arbitrary elevation of 100 feet is assigned to the datum. The first rod reading

from the instrument is entered on the form as a “backsight” to the benchmark. The rod 

reading is added to the datum to determine the height of the instrument (HI). Remaining rod readings are subtracted from the instrumentʼs height to determine elevations. 

Record rod readings and elevations in the survey table (field form, p. 2). Refer to 

Figure E-10 for a reminder about how to read elevations from a survey rod.

Figure E-10. Reading the survey rod.

Crossings with large fills or visual obstructions may require two level setups (Figure 

E-11). A turning point is a temporary benchmark that can be read from both setup locations. Like any benchmark, it should be marked so it can be accurately relocated. Read 

its elevation from level setup 1 to determine the ground elevation at the point; record 

the reading as a foresight. Then read it again from setup 2, recording it as a backsight. 

Determine HI2 by adding the rod reading to the ground elevation of the turning point. 

It is wise to have more than one turning point to ensure accuracy. Be sure you can

read the turning point elevation(s) from setup 2 before moving the level. Figure E-11 

shows sample survey calculations for a turning point. More complete instructions for 

surveying stream channels are in Harrelson (1994). They cover techniques for using 

a surveyorʼs level, as well as important channel features to capture in the survey (i.e., 

where to set the rod).

3 3

2

1

9

8

2

1

9

8

Rod 

Reading

Rod 

Reading • Rods are divided into:

 feet = red numbers

 tenths = black numbers

 one-hundreths lines

• Each line is 1⁄

100' thick

• View A = 7.08

• View B = 2.27

>

>

View A View B

Turning points
51

Figure E-11. Turning point scenario. (Note: is instrument location).

Figure E-12. Long profi le survey points.

At all culverts, the following elevation and distance (feet on tape) measurements are 

required (see Fig E-12):

• Benchmark—Describe the point used, take a rod reading, and determine the 

height of instrument by adding the rod reading to the benchmark elevation (by 

convention, BM1 elevation is usually taken as 100). Take the benchmark elevation before taking any other elevation measurements, and check it at the end of 

the site survey. On projecting pipes, an easy place to locate the benchmark is 

the fi rst corrugation at the top of the inlet.

• Inlet gradient control point (P1) and additional upstream point (P0)— The 

survey includes a short section above the culvert to represent channel conditions fi sh will face after exiting the pipe. P1 is the point used to calculate “inlet 

gradient”. It is usually the tallwater control for the fi rst resting pool above the 

culvert, where one exists. However, the point should be selected such that local 

adverse conditions immediately above the culvert are delineated. For example, 

where a culvert constricts high fl ows, sediment often deposits immediately upRoad surface

BS = 0.8

FS = 24.7

TP

1

2

SURVEY

 Station1 BS(+) HI FS(-) Elevation Notes

TP1 24.7 75.3 TP1 read from level set up 1

Move level set up 2

TP1 .8 76.1

105.6 12.9 63.2 P5 water depth = 3.1

107 66.3 WS5

F ig u re E 1 0 —Tu n in g p o in t s c e n a r io.

 Pool Bottom

Channel bottom

Culvert

Road surface Horizontal leap

distance for

analysis species

Culvert outlet 

invert

Channel point

downstream 

of tailwater

control

Tailwater control P6

P7

P5

P4

P3

P2

P1

First upstream resting

 pool control 

Culvert inlet invert

Water surface at outlet pool WS5
52

stream, creating a steep slope leading into the pipe that can block fish passage 

(see Figure E-15). Generally, such adverse inlet conditions are found within 

one culvert diameter upstream of the inlet. To fully represent the aggraded 

reach in the long profile, more points may be needed upstream of P1. As shown 

in Figure E-15, those points are numbered P0, P0a, P0b, etc. The same would 

be true in a step pool channel, if you want to show the height and frequency of 

natural steps.

 If the channel upstream is uniform with no special streambed features, additional points are not needed upstream of P1. For P1, select a point within about 

50ʼ of the pipe inlet—perhaps within 1-2 channel widths—that will represent 

the slope above the inlet.

• Culvert inlet invert (P2)—Used for determining culvert slope and slope at the 

inlet. Invert is the bottom inside surface of the culvert. If the inlet is embedded, 

measure the top of the substrate at the inlet.

• Roadway surface (P3)—Only an elevation is needed. Used to determine headwater depth for flood capacity calculations. If fill volume measurements are not 

taken, this can provide an index of fill removal costs. It can also be used for 

prioritization on the basis of crossing failure consequences.

• Culvert outlet invert (P4)—Used to determine culvert slope and outlet perch. 

Some culverts have concrete or riprap aprons lining the stream channel at the 

inlet or outlet to increase flood capacity and prevent scour at the outlet. Measure the slope of inlet and outlet aprons.

 These aprons are often velocity and depth barriers. Measure elevations at the 

top and bottom of the apron and adjacent points on the thalweg to calculate 

slope. Number the outlet apron points P4a, P4b, and so on. See Figure E-13.

Figure E-13. Detail of long profile points for outlet apron.

�P4a���������������� ��������������������

P4b�����������������

� P4c �������������������������������������������

P4

�

�

���������������������������P4c���������������������������P5�
53

• Pool bottom (P5)—Measure the lowest streambed elevation at a distance from 

the outlet that is within the leaping distance of the analysis species. If you have 

more than one analysis species, then you may need to take the elevation at 

more than one distance from the culvert. For adult salmon, five feet is often the 

maximum distance that is used; for juvenile fish the distance is a few inches. 

If a pool is lacking, survey the thalweg (the lowest point of channel crosssection) immediately downstream of the outlet. If the culvert is perched, this 

measurement determines if the take-off pool depth is adequate for making the 

jump.

• Water surface at outlet pool (WS5 or WS6)—This elevation can be taken in 

one of two ways. You can take the water depth at the pool bottom (P5) and then 

add water depth to the pool bottom elevation - record this elevation as WS5; or, 

if there is no pool take the measurements at the tailwater control. This measurement will usually be easiest to take at waterʼs edge—record this elevation 

as WS6.

• Outlet pool tailwater control (P6)—Used to determine perch, residual inlet 

depth, and residual pool depth. If no tailwater control feature is obvious, use 

the thalweg elevation of the cross-section adjacent to the outlet. Measure the 

tailwater control at the lowest average elevation of the bedform. See Figure 

E-14.

• Channel point downstream of tailwater control (P7)—The point should 

be far enough downstream of the tailwater control to represent water surface 

slope across and downstream of the control. Used for modeling flow through 

the tailwater cross-section in FishXing.

• Water surface at P7—Measure this at the waterʼs edge at P7.

Water surface measurements are required for the outlet pool and at P7 because the water surface slope is a better representation of hydraulic slope across the tailwater cross 

section than bed slope. Many practitioners take water surface elevations (or water 

depths) at all profile points as a check on recorded streambed elevations. Water depths 

can be recorded in the notes field of the profile survey form.

Other survey points may be needed to characterize passage conditions.

For example:

• Apparent breaks in slope in the culvert—Older culverts can bend when 

roadfills slump, creating steeper sections in a culvert. If only inlet and outlet 

elevations are measured in a sagging culvert, steeper sections that may act as 

barriers will be missed.

The tailwater cross-section is used to estimate tailwater elevation at various flows by 

building a stage-discharge rating curve. This method is used in FishXing to determine 

the water-surface profile in low gradient culverts, and to estimate perch height and 

pool depths at various flows. The only time a tailwater cross-section is not needed is 

when a constant tailwater elevation is assumed (such as, lakes, beaver ponds). The 

tailwater control may be a natural or constructed boulder, cobble or gravel step, or a 

log structure. Locate the cross-section at the tailwater control, perpendicular to flow.

Where no particular structure is controlling the water-surface elevation downstream of 

the crossing, the bed and bank resistance control tailwater elevations. Then, locate the 

cross-section very near the outlet. Cross-sections typically start (station 0.0 feet) on 

the left bank looking downstream. Place a tape securely across the channel no lower 

than bankfull elevation. If feasible, conduct the cross-section survey without moving 

Tailwater 

cross-section
54

the survey instrument (the instrumentʼs height is the same as for the profile survey). 

Survey elevations at obvious breaks in slope. Record horizontal distance to each surveyed point from the cross-section starting point, and the rod reading. Describe point

locations, such as bankfull channel margin, edge of water, toe of bank, thalweg, midchannel bar, edge of rooted vegetation, and so on. See Figure E-14.

Figure E-14. Measuring the tailwater control.

A simplified tailwater-control cross-section with fewer points can be used in FishXing. 

The data needed are as follows:

• Tailcrest elevation (lowest average elevation of the tailwater control);

• Tailcrest bedwidth;

• Bankfull elevation; and

• Bankfull width.

This method simplifies the tailwater control to a trapezoidal cross-section.

Mark the appropriate line. For a crossing structure to meet the criteria for natural 

channel simulation, structures must have streambed substrate throughout. A continuous layer of substrate, and bedform types similar to those in the adjacent channel 

help ensure that the organisms moving in the stream can move through the structure. 

Measurements of the depth of sediment and its location (if sediment does not cover the 

entire length of the pipe) are made most efficiently during the profile survey. Measure 

the depth of the streambed substrate at the inlet and the outlet ends of the structure,

even if substrate does not extend throughout the structureʼs entire length. Structure 

height and substrate depth can be difficult to measure in pipe arch and box culverts 

that contain sediment throughout, and guesswork can cause errors. See discussion of 

“Culvert Dimensions.”

Streambed substrate 

retention

Detail View

Do not place rod in small low pocket. 

Select lowest average elevation

representative of tail water control.

Typical Tail Crest Cross–Section

Toe of bank Tail Crest elevation is measured at the

lowest point in the stream–cross section

Bankfull Elevation

Toe of bank

Measuring Rod

Figure E-7
55

Rank (1-highest) the first three substrate sizes that occupy the greatest area of the 

streambed. Take the substrate sizes in three locations:1) in the structure, 2) at the tai 

water control, and 3) in the channel outside the influence of the crossing. Usually the 

last observation is taken at the same location as the channel width and slope measurements (and reference cross section, if included). Substrate sizes from locations 1) and 

2) are needed to calculate Mannings “n” roughness coefficients for FishXing. Substrate size around the reference cross-section determines the roughness value used to

calculate flows through that cross-section. All three locations are used to evaluate if 

the crossing resembles the adjacent natural stream channel and for pre-design replacement cost-estimates.

Use the following definitions of substrate particle sizes:

• Bedrock = large masses of solid rock;

• Boulder = > 256 mm (>10 inches);

• Cobbles = 64 to 256 mm (2.5 to 10 inches);

• Gravel = 2 to 64 mm (0.08 to 2.5 inches);

• Sand = .06 mm to 2 mm(< 0.08 inches);

• Silt and clay = difficult to differentiate individual grains;

• Organics = muck, organic ooze; and

• Aquatic macrophytes (rooted aquatic vegetation).

Measure the width of the channel at the bankfull level. Five measurements (including the cross-section, if measured) should be taken across straight stretches of the 

channel and then averaged. Space the five measurements out over the reach used to 

measure channel gradient (8-10 channel widths in length), which should be well above 

any influence the stream crossing may have on channel width or slope. Undersized 

culverts can influence the channel width for several hundred feet upstream as a result 

of ponding storm runoff and causing bedload deposition. Because crossings are often 

near natural slope breaks, look for significant channel changes near the crossing. If 

upstream and downstream reaches are very different, slope and width should be measured on both reaches.

In many places, bankfull discharge is a high flow occurring every one to two years 

on average. Bankfull elevation can be tricky to identify in the field, and field personnel should be thoroughly trained by specialists familiar with the hydrologic regime, 

stream morphology, and riparian vegetation of the area. Information on how to recognize bankfull elevation can be found in “Applied River Morphology” by Dave Rosgen, “Stream Channel Reference Sites” by C.C. Harrelson and others, and two videos 

published by the Stream Team: “A guide to Field Identification of bankfull stage in the

western United States”, and “Identifying bankfull stage in forested streams in the 

eastern United States” (www.stream.fs.fed.us).

Substrate particle 

sizes

Bankfull channel 

widths
56

Figure E-15. Survey calculations.

Calculate the following, using the surveyed elevations and distances (See

Figure E-15):

• Culvert slope—Culvert slope in percent is the inlet outvert elevation minus 

the inlet invert elevation divided by the horizontal culvert length, multiplied by 

100. In general, culvert slopes and lengths are such that, for assessment purposes, slope distance can be used in this calculation. Use streambed elevations 

for embedded culverts.

• Outlet drop—The outlet drop is the jump at the outlet of the structure that a 

fi sh must negotiate to enter the structure. At extreme low fl ows the outlet drop 

is controlled by the substrate elevation at the tailwater of the outlet pool (Figure 

E-15). The total outlet drop is the elevation difference between the outlet invert 

and the downstream tailwater control. Tailwater elevations will be higher than 

the lowest point in the tailwater control, as long as fl ow continues across the 

control; the outlet drop measurement represents the highest jump possible (the 

jump that would be needed at zero fl ow). Where hydrologic data indicate that 

Survey calculations

��������������P4���P6

��������

������������

��������������

P0

P2

P4

P6

P0a P1

Culvert Inlet Road Surface

Tailwater

Control

Residual Pool

Depth

Residual Inlet

Depth

Water Surface

Slope (+)

Road Fill

P1

P2

P6

Inlet gradient =

elevation P1 - P2

 distance P1 P2

P4

Residual Pool Depth = (P6 - P5)

Residual lnlet Depth = (P6 - P2 )

* 100 Culvert slope =

elevation P2 - P4

 distance P2 P4 * 100

Backwatered culvert

Perched culvert with sediment accumulation above inlet.

���������������� ����������P1 ��P2

� ������������������������������������������������������������������������������������������P1����P2 * 100
57

flows never approach zero, as in spring-fed streams, this calculation will give 

an unrealistic overestimate of perch height. In this situation the analyst should 

make allowance for low-flow water depth.

• Channel gradient—The difference in the elevation of the water surface measured at two points along the natural channel divided by the length of channel 

between those two points (use up and downstream ends of channel segments, 

measured under “channel slope”). The measured length should follow the 

streamʼs course and not the shortest distance between two points. Calculate 

both upstream and downstream gradients if they are different.

• Inlet gradient—Calculate the gradient immediately upstream of the inlet as an 

indicator of adverse inlet conditions. Passage may be impaired if channel gradient directly above the structure is steeper than the average channel gradient.

• Inlet width to bankfull channel width ratio—For a crossing structure to 

meet the criteria for stream simulation, this ratio must be 1 or greater. Structures that do not constrict the channel at most flows are generally more successful at passing fish and other biota.

• Residual inlet depth (P6 – P2)—The residual inlet depth is the depth of water 

at the inlet of the structure under no or very flow. When the outlet tailwater 

control elevation is higher than the invert of the inlet, the residual inlet depth 

will be a positive number and the structure will be backwatered at all flows. A 

positive residual inlet depth is generally conducive to passage of most species 

and life stages. Write 0 if the tailwater control is lower than the inlet invert.

• Residual pool depth (P6 – P5)—The residual pool depth is the depth of water 

in the outlet pool under no or very low flow. Some species, notably salmonids, 

may be able to negotiate an outlet drop providing there is a jump pool of sufficient depth is present.

• Substrate ratio—The substrate ratio is the ratio of the depth of the substrate 

to the height of an embedded structure. Substrate ratio is important to the function of structures that simulate the stream. The substrate must be deep enough 

that the channel inside the structure is able to adjust vertically over the range 

of design flows. Generally 20% depth of embedment is considered a minimum.

Unvented fords that have some accommodation for fish passage may be surveyed if, 

for example, baseline measurements are desired for later comparison. Channel and 

ford widths and slopes, as well as any grade breaks, should be the focus of the survey.

Use the following assessment criteria to determine the barrier category of

the crossing structure.

Check ʻresembles natural channelʼ if:

• The streambed substrate is continuous through the structure;

• The inlet width is greater than the channel width (inlet width to channel bankfull width ratio > 1.0);

• No outlet drop exists, and

• No other obvious factors are affecting passage (such as, trash racks or drop 

inlets) are present.

Field passage 

evaluation
58

If the structure does not meet these criteria, then use the analysis species regional 

coarse filter criteria to categorize the crossing. The categories include: passage adequate, passage inadequate, or when passage is uncertain, passage indeterminate. List 

the species, lifestage, or species group that the regional criteria are based on. If your 

evaluation differs from the coarse filter assessment criteria, be sure to explain why.

Use this section to:

• Clarify items that may not be clear in the data, the site sketch, or the photographs;

• Describe any data-gathering problems;

• Record qualitative notes describing stream habitat immediately upstream and 

downstream of the crossing;

• Report any fish present at the site; include number, size, and species, if known 

(remember that rigorous inventory methods are needed to document species 

absence);

• Note any possible upstream or downstream barriers;

• Bank vegetation near the culvert; and

• Describe any substrate structure inside the pipe (such as, step-pools, meandering, presence of a low flow channel, or substrate exposed at low flows that 

might be usable by crawling species).

• Photograph all culvert locations. At a minimum, photographs of the inlet, outlet, and tailwater control of each culvert are required. We also recommend that 

a photo be taken from the inlet looking upstream to show streambed conditions 

and possible obstacles for exiting fish. For low-water crossings, take photos 

from both upstream and downstream. Where multiple structures are present, 

photograph all of them to show their locations and arrangements. Also show 

the driving surface of fords. For information on using spatially referenced photographic techniques to document the survey, see http://csmres.jmu.edu/forestservice.

• Record the global positioning system location of the photo points if desired.

• On the site sketch, mark your photo points so future photographs can be taken 

from the same places.

• Photograph any unique features about a site, such as steep drops at inlets; 

perched outlets; breaks-in-slope; poor or damaged condition; outlet pool conditions; and habitat above and below the site.

Sketch each stream crossing and the surrounding site, including relevant features of 

the adjacent stream reaches. The sketch and notes are as important as the data collected. Include the following features in site sketches:

• North arrow;

• Direction of stream flow, road number/name, and stream name;

• Alignment of stream channel and culvert inlet;

• Locations of photo points;

• Wingwalls and inlet /outlet aprons and their dimensions;

Comments

Photographs

Site sketch
59

• Locations and designations of multiple structures at one site;

• Baffle configuration, dimensions, and number of sets;

• Weirs and other instream structures;

• Upstream or downstream debris jams;

• Trash racks, screens, standpipes, drop inlets, or any other structure associated 

with the crossing that may affect passage;

• Damage or obstacle inside structure;

• Location and quantity of riprap for bank armoring or jump pool formation. 

How the culvert is aligned with the upstream channel can have very important effects 

on aquatic species passage and should be well documented on the sketch. A severe 

angle of approach to the inlet (see Figure E-16) can cause floating pieces of wood to 

plug the culvert, and can induce sediment deposition, bank erosion and inlet scour in 

some open-bottom structures. If the inventory will be used for preliminary design, 

the sketch should also show stream meanders and side channels in the vicinity of the 

crossing.

Figure E-16. The site sketch should show stream location, with special attention to 

culvert inlet and outlet. It should include any erosion and deposition features. 

Low and high passage flows needed in FishXing are often derived from USGS regression equations with large standard errors of estimation. A reference cross-section can 

be surveyed to help determine if the results are reasonable. To get an independent 

estimate of bankfull flow, average cross section velocity and discharge are calculated 

from the hydraulic slope, cross section geometry and roughness. Several methods are 

described in detail in the WinXSPRO Userʼs Manual (USDA-FS 1998).

The cross-section should be located outside the area of influence of the culvert—usually upstream—and should be in a relatively uniform, straight channel section. Use the 

same procedure described for the tailwater cross-section.

Reference 

cross-section 

(optional)
60

Slope is needed for the reference cross-section flow calculations. Some practitioners 

also measure it both up and downstream to establish the crossingʼs context within the 

longitudinal profile of the natural channel. Often roads are built on slope breaks and 

the up and downstream gradients are quite different. Determine the natural channel 

gradient by measuring water surface slope. Take several elevations at the waterʼs edge 

along a representative segment of stream that is outside the crossingʼs influence. Segments should be at least 8-10 channel widths long and the endpoints should be taken at 

similar streambed locations, preferably at riffles or runs.

Usually you will need to move away from the crossing to get representative channel 

slope measurements. If moving the level is awkward because of dense vegetation, you 

can use a hand level mounted on a rod of known height. With a hand level, several 

points on the water margin elevations are likely to be needed because the rod cannot be 

read at long distances. Record rod readings and distances between each measurement. 

As the two crewmembers move progressively up or down the channel, the next rod 

reading must be taken from the exact spot the rod was held for the previous reading. 

Note that when this method is used, the channel slope measurement may not be tied 

into the survey benchmark.

This sheet documents critical information needed to complete the permanent record 

of the site survey, and to assist in making prioritization decisions. Field crews do not 

need this page in the field.

Because passage requirements are specific to species, lifestage (size), or species 

groups1, so are barrier determinations. The inventory procedure described here results 

in enough data to assess passage for many fish species, life stages, or species groups in 

most situations. Your list of species may be broader than fish, however. Therefore, we 

recommend identifying specific species, life stages, or species groups in the planning 

stages, to allow for the eventuality that additional data might need to be collected for 

these non-fish species.

List the species, life stages, or species groups for that will be used in to assess passage 

at the crossing. In the comment section, note the reason for choosing each species.

Record the length of upstream and downstream habitat that will become accessible 

by restoring passage at the site. To make this a more complete prioritization tool, also 

note habitat quality.

Record upstream and downstream crossings separately. If there are upstream crossings 

in the watershed, record the number. Record the distance in feet to the nearest upstream crossing (1st crossing) and check yes or no to indicate if it is a known barrier for 

the selected species. Do the same for the next nearest upstream crossing (2nd crossing). 

Follow this same procedure for downstream crossings and for other barriers and record 

the results in the spaces provided.

The presence of other barriers in the drainage network is important information for 

deciding the amount of benefit that will be gained by restoring passage at the crossing.

Channel slope outside 

of structure’s influence 

(Optional)

Biological and 

watershed 

information

Analysis species

Length of upstream 

and downstream 

habitat (prioritization 

data)

Upstream and down- stream crossings and 

other potential barriers 

(prioritization data)

1 Species group: A group of species with similar morphology, swimming capability and behavior. The capability is used 

to determine the values in the regionally defined flowchart that classifies the passage status of a crossing.
61

Indicate whether the barrier is to be left in place to limit the upstream expansion of 

exotic species. This information will be input to INFRA. (Footnotes)

Crossing is a barrier 

to exotic species
62
63

Passage Through Crossings Assessment 

SITE

Forest ____________________ District _____________________

Route number: _________ INFRA milepost: ______________

Milepost: _________from junction of road no. ________________

Watershed 6th HUC or name: ________________________Stream name: _______________________________

7.5-minute quad name: _______________________ Land ownership: ______ NF _______ Other: _________

Legal description: T. _ _ S / N, R. _ _ E / W, Sec. _ _, _ _ 1⁄4 of _ _ 1⁄4 Principal meridian___________________

X/Y Coordinates ____________________________ Coordinate system ______________Datum___________

Surveyor names: __________________________________________________ Field date: ___ / ____ / ____

CROSSING STRUCTURE

Shape Dimensions (inches)

Circular width: _________ height: _________

Box

Open-bottom arch Rust line: __________ (feet)

Pipe-arch

Ford Ford data: sag _______

Vented ford F1 _______

Bridge F2 _______

Other: _______________

Structure shape comments______________________________________________________________________

Structure material Corrugations Skew from road

Spiral CMP 2 2/3 x 1⁄2 inch

Annular CMP Steel Aluminum 3 x 1 inch ____degrees

Structural plate 5 x 1 inch

Concrete 6 x 2 inch (SSP only)

PVC None

Wood or log Paved or smooth invert

Other: _____________________ Other: ________________________________

Inlet type Outlet configuration

Projecting at stream grade

Mitered cascade over riprap

Wingwall 10-30o freefall into pool

Wingwall 30-70o freefall onto riprap

Headwall outlet apron

Apron Other: ________________

Trashrack Describe: ________________

Other: ___________ ________________________

Describe: ___________ ________________________

___________________ ________________________

Baffles, weirs or other internal structures: Yes No Material: __________________________________

Describe (see sketch): ____________________________________________________________________________

Pipe condition: Breaks inside culvert (Location__________________)

Fill eroding Debris plugging inlet (% blockage______) Bent inlet Bottom worn through

Poor alignment with stream Debris in culvert (rock or wood) Bottom rusted through Water flowing under culvert

Other __________________________ Describe overall condition _______________________________________

______________________________________________________________________________________________

Diversion Potential: Yes No Comments:

Crossing ID number _______________

Structure of _______

Structure milepost_____________________

Multiple structures at site:

___# other openings identical to main structure

Mileposts _______________________

___# different openings with forms completed

___ # overflow pipes----no forms completed

Mileposts______________________________

___ # overflow pipes with forms completed

Fill Volume

Lu (upstream fill slope length):________

Ld (downstream fill slope length):_______

Su (slope of upstream fill):______%

Sd (slope of downstream fill):______%

Wr (Road Width):_______

Wf (length of road on fill): ______

Wc (length of fill base):____________
64

Crossing ID Number _________________________ Structure of ____

SURVEY.

Station1 BS (+) HI FS (-) Elevation

(ft)

Notes

100.00

Tailwater Cross Section

Describe:

Station1 BS (+) HI FS (-) Elevation

(ft)

Notes

Long profile (required points) Tailwater cross-section

(minimum recommended points)

P1 inlet gradient control point Left bankfull

P2 inlet invert Left edge of water

P3 roadway surface Left toe of bank

P4 outlet invert Thalweg

P5 pool bottom Right toe of bank

WS5 or WS6 water surface at outlet pool taken at P5 or P6 Right edge of water

P6 tailwater control Right bankfull

P7 downstream end of profile

WS7 water surface at P7

 1 Station: The distance (ft) along the profile or transect from the starting point.
65

Crossing ID number _________________________ Structure of ____

STREAMBED SUBSTRATE RETENTION IN STRUCTURE

No substrate in structure

Discontinuous layer of substrate in structure begins at _______ ft; ends at ________ft (measured from inlet)

Substrate is continuous throughout structure

If present, substrate depth at inlet ________ft;substrate depth at outlet ________ ft

SUBSTRATE PARTICLE SIZES number 1up to 3 in order of sizes occupying most streambed area

Bedrock Boulders Cobbles Gravel Sand Silt/Clay Organics Aquatic

macrophytes

Culvert

Downstream near

tailwater control

BANKFULL channel widths---outside of culvert influence (ft): (1) _____________ (2) _____________ 

(3) _____________ (4) _____________ (5) _____________ Average ___________

CALCULATIONS FROM SURVEY

Culvert slope: _ _. _ % elev (P2 - P4) *100 Outlet drop (F): _ _. _ (P4 minus P6)

dist (P2 – P4)

Channel gradient: ____ % upst; _____% downst Inlet gradient: ___ % elev (P1 - P2) x (100)

dist (P1 – P2)

Ratio of inlet width to channel width : _____ Residual inlet depth: ______ (P6 – P2)

Substrate ratio: ____(depth of substrate/structure height) Residual pool depth: _______ (P6 – P5)

 

 

 

 

 

 

FIELD PASSAGE EVALUATION

__ Resembles natural channel __ Passage adequate (species/lifestage) ___________________________

__ Passage indeterminate __ Passage inadequate (species/lifestage) ____________________________

Comments:

___________________________________________________________________________

_________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________
66

Crossing ID number _________________________ Structure of ____

Comments: (See instructions for list of potential items needing comments)

__________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

PHOTOGRAPHS---identify and provide captions

Photo caption X/Y Coordinates Comments

1. Inlet from upstream

2. Outlet from downstream

3. Tailwater control

Required photos:

1. Inlet from upstream

2. Outlet from downstream

3. Tailwater control
67

Crossing ID number _________________________ Structure of ____

SITE SKETCH

Include:

North Arrow

Direction of stream flow

Culvert/channel alignment

Lay of tape if needed

Photo point locations and numbers

Wingwalls and inlet / outlet aprons

Multiple structures

Baffle configurations

Weirs and other instream structures

Debris jams inside, upstream and downstream near site, depositional bars

Trash racks, screens, standpipes etc. that may affect passage

Damage to or obstacle inside structure

Location of Riprap for bank armoring or jump pool formation

Tailwater cross-section location
68

Optional Channel Reference Data

Crossing ID Number _________________________ Structure of ____

CHANNEL SLOPE---- measured outside of culvert influence

Upstream (include upstream channel cross section in reach)

Slope = cumulative elevation change/cumulative distance

Station BS (+) HI FS (-) Elevation Cumulative

elevation change

Upstream slope ____________

Downstream

Station BS (+) HI FS (-) Elevation Cumulative

elevation change

. Downstream slope _______________

Note: Slope measurements should be taken at the water surface and at the same stream feature (such as, pool and

pool, or riffle and riffle).

Reference cross-section

Describe location:

Station BS (+) HI FS (-) Elevation

(ft)

Notes

Reference cross section recommended points (minimum)

Measured Discharge _________cfs

Left bankfull Thalweg Right toe of bank

Left edge of water Right edge of water Manning’s n __________

Left toe of bank Right bankfull
69

Crossing ID number _________________________

Site Biological information – (Core data and prioritization data)

ANALYSIS SPECIES

Core data Prioritization data

Species Life Stage Comments Upstream habitat Downstream habitat

blocked (mi) blocked (mi) 

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

Habitat Quality Notes:

Watershed Information – Prioritization data

Exotic Species Crossing Barrier

Is a barrier necessary at this site to meet management objectives, that is---passage barrier okay?

Yes No

Upstream crossings: No. of crossings______

Distance to 1stcrossing (ft): Barrier Y N

Distance to 2nd crossing (ft): Barrier Y N

Downstream crossings: No. of crossings______

Distance to 1stcrossing _________ mi Barrier Y N

Distance to 2nd crossing __________mi Barrier Y N

Other upstream barriers: No. of barriers: ________

Distance to 1stbarrier: __________mi Height ______ft

Distance to 2nd barrier: __________ mi Height _____ft

Other downstream barriers: No. of barriers ________

Distance to 1stbarrier: __________mi Height ______ft

Distance to 2nd barrier: _________ mi Height _______ft

71

Passage Through Crossings Assessment 

Multiple Structures Supplemental Form

CROSSING STRUCTURE

Shape Dimensions (inches)

Circular width: _________ height: _________

Box

Open-bottom arch Rust line: __________ (feet)

Pipe-arch

Ford Ford data: sag _______

Vented ford F1 _______

Bridge F2 _______

Other: _______________

Structure shape comments______________________________________________________________________

Structure material Corrugations Skew from road

Spiral CMP 2 2/3 x 1⁄2 inch

Annular CMP Steel Aluminum 3 x 1 inch _____degrees

Structural plate 5 x 1 inch

Concrete 6 x 2 inch (SSP only)

PVC None

Wood or log Paved or smooth invert

Other: _____________________ Other: _____________________

Inlet type Outlet configuration

Projecting at stream grade

Mitered cascade over riprap

Wingwall 10-30o freefall into pool

Wingwall 30-70o freefall onto riprap

Headwall outlet apron

Apron Other: ________________

Trashrack Describe: ____________________________________

Other: ___________ ____________________________________________

Describe: _________________________________ _____________________________________________

_________________________________________

Baffles, weirs or other internal structures: Yes No Material: __________________________________

Describe (see sketch): ____________________________________________________________________________

Pipe condition: Breaks inside culvert (Location__________________)

Fill eroding Debris plugging inlet (% blockage______) Bent inlet Bottom worn through

Poor alignment with stream Debris in culvert (rock or wood) Bottom rusted through Water flowing under culvert

Other __________________________ Describe overall condition _______________________________________

______________________________________________________________________________________________

______________________________________________________________________________________________

Diversion Potential (prioritization data): Yes No Comments:

Crossing ID number _______________

Structure______of _______

Structure milepost ________________
72

Multiple Structures Supplemental Form

Crossing ID Number _________________________ Structure ____ of ____

SURVEY.(Use same control points as for structure 1. Integrate survey if possible.)

Station1 BS (+) HI FS (-) Elevation

(ft)

Notes

100.00

Tailwater Cross Section (only applicable if in a different channel from structure 1 (eg. side channel)

Describe:

Station1 BS (+) HI FS (-) Elevation

(ft)

Notes

Long profile (required points) Tailwater cross-section

(minimum recommended points)

P1 inlet gradient control point Left bankfull

P2 inlet invert Left edge of water

P3 roadway surface Left toe of bank

P4 outlet invert Thalweg

P5 pool bottom Right toe of bank

WS5/6 water surface at outlet pool taken at P5 or P6 Right edge of water

P6 tailwater control Right bankfull

P7 downstream end of profile

WS7 water surface at P7

 1 Station: The distance (ft) along the profile or transect from the starting point.
73

Multiple Structures Supplemental Form

Crossing ID number _________________________ Structure ____ of ____

STREAMBED SUBSTRATE RETENTION IN STRUCTURE

No substrate in structure

Discontinuous layer of substrate in structure begins at _______ ft; ends at ________ft (measured from inlet)

Substrate is continuous throughout structure

If present, substrate depth at inlet _____ ft; substrate depth at outlet _____ ft

SUBSTRATE PARTICLE SIZES number 1up to 3 in order of sizes occupying most streambed area

Bedrock Boulders Cobbles Gravel Sand Silt/Clay Organics Aquatic

macrophytes

Culvert

Downstream near

tailwater control

BANKFULL channel widths---outside of culvert influence (ft): (1) _____________ (2) _____________ 

(3) _____________ (4) _____________ (5) _____________ Average ___________

CALCULATIONS FROM SURVEY

Culvert slope: _ _. _ % elev (P2 - P4) *100 Outlet drop (F): _ _. _ (P4 minus P6)

dist (P2 – P4)

Channel gradient: ____ % upst; _____% downst Inlet gradient: ___ % elev (P1 - P2) x (100)

dist (P1 – P2)

Ratio of inlet width to channel width : _____ Residual inlet depth: ______ (P6 – P2)

Substrate ratio: ____(depth of substrate/structure height) Residual pool depth: _______ (P6 – P5)

 

 

 

 

 

 

FIELD PASSAGE EVALUATION (use if in different channel from structure 1)

__ Resembles natural channel __ Passage adequate (species/lifestage) ___________________________

__ Passage indeterminate __ Passage inadequate (species/lifestage) ____________________________

Comments:

___________________________________________________________________________

_________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________

___________________________________________________________________________
74

Multiple Structures Supplemental Form

Crossing ID number _________________________ Structure ____ of ____

Comments: (See instructions for list of potential items needing comments)

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________

PHOTOGRAPHS---identify and provide captions

Photo caption X/Y Coordinates Comments

1. Inlet from upstream

2. Outlet from downstream

3. Tailwater control

Required photos:

1. Inlet from upstream

2. Outlet from downstream

3. Tailwater control
75

Multiple Structures Supplemental Form

Crossing ID number _________________________ Structure ____ of ____

SITE SKETCH (Only use if this structure is at some distance from structure 1. All related structures

should be on same sketch.)

Include:

North Arrow

Direction of stream flow

Inlet/channel alignment—include compass bearing for pool alignments

Lay of tape if needed

Photo point locations and numbers

Wingwalls and inlet / outlet aprons

Multiple structures

Baffle configurations

Weirs and other instream structures

Debris jams inside, upstream and downstream near site, depositional bars

Trash racks, screens, standpipes etc. that may affect passage

Damage to or obstacle inside structure

Location of Riprap for bank armoring or jump pool formation

Tailwater cross-section location