Appendix G 

Natural Ecological Systems and Wildlife 

Technical Study

In coordination with Oklahoma DOT

Natural Ecological Systems and 

Wildlife 

Technical Study

July 2016

TBG101414223433SCO 

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page iii

Contents 

Abbreviations and Acronyms ................................................................................................................. vii 

1.0 Introduction .............................................................................................................................. 1-1 

1.1 Service Type Descriptions .............................................................................................. 1-4

Conventional Rail.......................................................................................................... 1-4

Higher-Speed Rail ......................................................................................................... 1-4

High-Speed Rail............................................................................................................. 1-4

1.2 Alternative Descriptions ................................................................................................. 1-5

No Build Alternative ...................................................................................................... 1-5

Northern Section: Oklahoma City to Dallas and Fort Worth....................................... 1-6

Central Section: Dallas and Fort Worth to San Antonio ............................................. 1-7

Southern Section: San Antonio to South Texas .......................................................... 1-9

Station Cities............................................................................................................... 1-10

2.0 Regulatory Context and Purpose ............................................................................................. 2-1 

3.0 Evaluation Methods ................................................................................................................. 3-1 

4.0 Baseline/Affected Environment .............................................................................................. 4-1 

4.1 EIS Study Area ................................................................................................................. 4-1

4.2 Regional Environment .................................................................................................... 4-1

4.3 Regulatory Environment ................................................................................................. 4-1

4.4 U.S. EPA Level III Ecoregions .......................................................................................... 4-2

Central Great Plains...................................................................................................... 4-6

Cross Timbers ............................................................................................................... 4-6

East Central Texas Plains............................................................................................. 4-6

Southern Texas Plains/Interior Plains and Hills with Xerophytic Shrub and Oak 

Forest............................................................................................................................. 4-6

Texas Blackland Prairies .............................................................................................. 4-7

Western Gulf Coastal Plain .......................................................................................... 4-7

4.5 National Land Cover Database – Land Cover Types .................................................... 4-7

Water ............................................................................................................................. 4-8

Developed ..................................................................................................................... 4-8

Barren............................................................................................................................ 4-8

Forest............................................................................................................................. 4-9

Shrubland...................................................................................................................... 4-9

Herbaceous ................................................................................................................... 4-9

Planted/Cultivated........................................................................................................ 4-9

Wetlands ..................................................................................................................... 4-10

4.6 Wildlife Corridors and Assemblages and Sensitive Plant Communities .................. 4-13

4.7 Regional Ecological Assessment Protocol (REAP) Composite Score ........................ 4-22
TBG101414223433SCO 

Contents

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page iv

5.0 Effects on Natural Ecological Systems and Wildlife ............................................................... 5-1 

5.1 No Build Alternative ........................................................................................................ 5-1

National Land Cover Database – Land Cover Types .................................................. 5-1

Wildlife Corridors and Assemblages and Sensitive Plant Communities ................... 5-1

REAP Composite Scores............................................................................................... 5-2

5.2 Northern Section: Oklahoma City to Dallas and Fort Worth ......................................... 5-2

National Land Cover Database – Land Cover Types .................................................. 5-2

Wildlife Corridors and Assemblages and Sensitive Plant Communities ................... 5-2

REAP Composite Scores............................................................................................... 5-2

Potential Construction Effects ..................................................................................... 5-2

Potential Operations Effects ........................................................................................ 5-3

5.3 Central Section: Dallas and Fort Worth to San Antonio ............................................... 5-3

National Land Cover Database – Land Cover Types .................................................. 5-3

Wildlife Corridors and Assemblages and Sensitive Plant Communities ................... 5-3

REAP Composite Scores............................................................................................... 5-4

Potential Construction Effects ..................................................................................... 5-4

Potential Operations Effects ........................................................................................ 5-4

5.4 Southern Section: San Antonio to South Texas ............................................................ 5-5

National Land Cover Database – Land Cover Types .................................................. 5-5

Wildlife Corridors and Assemblages and Sensitive Plant Communities ................... 5-6

REAP Composite Scores............................................................................................... 5-6

Potential Construction Effects ..................................................................................... 5-6

Potential Operations Effects ........................................................................................ 5-7

5.5 Summary of Potential Effects ......................................................................................... 5-7

5.6 Subsequent Analysis and Avoidance, Minimization, and Mitigation Strategies ......... 5-7

6.0 References ............................................................................................................................... 6-1 

7.0 Preparers .................................................................................................................................. 7-1 
TBG101414223433SCO 

Contents

Texas-Oklahoma Passenger Rail Study July 2016 

Natural Ecological Systems and Wildlife Technical Study Page v 

List of Figures 

1-1: Build Alternatives ............................................................................................................................ 1-2

4-1: U.S. EPA Level III Ecoregions – Northern Section Alternative ...................................................... 4-3

4-2: U.S. EPA Level III Ecoregions – Central Section Alternatives ....................................................... 4-4

4-3: U.S. EPA Level III Ecoregions – Southern Section Alternatives .................................................... 4-5

4-4: Wildlife Corridors/Assemblages and Communities – Northern Section Alternative ............... 4-15

4-5: Wildlife Corridors/Assemblages and Communities – Central Section Alternatives ................ 4-16

4-6: Wildlife Corridors/Assemblages and Communities – Central Section Alternatives ................ 4-17

4-7: Wildlife Corridors/Assemblages and Communities – Southern Section Alternatives ............. 4-18

4-8: Wildlife Corridors/Assemblages and Communities – Southern Section Alternatives ............. 4-19

4-9: Wildlife Corridors/Assemblages and Communities – Southern Section Alternatives ............. 4-20

4-10: Wildlife Corridors/Assemblages and Communities – Southern Section Alternatives ........... 4-21

4-11: REAP Composite Scores – Northern Section Alternative ........................................................ 4-23

4-12: REAP Composite Scores – Northern Section Alternative ........................................................ 4-24

4-13: REAP Composite Scores – Central Section Alternatives ......................................................... 4-25

4-14: REAP Composite Scores – Central Section Alternatives ......................................................... 4-26

4-15: REAP Composite Scores – Southern Section Alternatives ...................................................... 4-28

4-16: REAP Composite Scores – Southern Section Alternatives ...................................................... 4-29

4-17: REAP Composite Scores – Southern Section Alternatives ...................................................... 4-30

4-18: REAP Composite Scores – Southern Section Alternatives ...................................................... 4-31

List of Tables 

1-1: Alternatives Carried Forward for Further Evaluation .................................................................... 1-3

1-2: Cities with Potential Stations ....................................................................................................... 1-10

4-1: Acres of Potential Land Cover Types within EIS Study Area – Northern Alternative N4A

Conventional Rail .......................................................................................................................... 4-10

4-2: Acres of Potential Land Cover Types – Central Section Alternatives ........................................ 4-11

4-3: Acres of Potential Land Cover Types within EIS Study Area – Southern Section..................... 4-13

4-4: Acres of Potential REAP Composite Ranking Land Coverages – Northern Section ................. 4-22

4-5: Acres of Potential REAP Composite Ranking Land Coverages – Central Section ................... 4-27

4-6: Acres of Potential REAP Composite Ranking Land Coverages – Southern Section ................ 4-27

5-1: Summary of Acreages and Effects ................................................................................................. 5-9

TBG101414223433SCO

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page vii

Abbreviations and Acronyms 

BMP best management practice

CWA Clean Water Act

EIS environmental impact statement 

EPA U.S. Environmental Protection Agency 

FRA Federal Railroad Administration

HrSR higher-speed rail

HSR high-speed rail

IH Interstate Highway 

KCS Kansas City Southern

mph miles per hour 

MRLC Multi-Resolution Land Characteristics 

NEPA National Environmental Policy Act 

NLCD National Land Cover Database 

NOAA National Oceanic and Atmospheric Administration 

NPS National Park Service 

NRCS Natural Resources Conservation Service 

ODWC Oklahoma Department of Wildlife Conservation 

Program Texas-Oklahoma Passenger Rail Program 

REAP Regional Ecological Assessment Protocol 

Study Texas-Oklahoma Passenger Rail Study

TPWD Texas Parks and Wildlife Department 

TRE Trinity Railway Express 

TxDOT Texas Department of Transportation

U.S.C. United States Code

USFWS U.S. Fish and Wildlife Service 

TBG101414223433SCO 

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 1-1 

1.0 Introduction 

The Texas Department of Transportation (TxDOT), along with the Federal Railroad Administration 

(FRA), is preparing a service-level environmental impact statement (EIS) to evaluate intercity 

passenger rail service alternatives for the Texas-Oklahoma Passenger Rail Program (Program). The 

purpose of the Program is to enhance intercity mobility by providing enhanced passenger rail 

service as a transportation alternative that is competitive with automobile, bus, and air travel.

Preparation of the service-level EIS, in support of which this technical study has been prepared, is 

one of two primary objectives of the Texas-Oklahoma Passenger Rail Study (Study). In addition to 

the service-level EIS, TxDOT and FRA are preparing a service development plan for the corridor to 

guide further development and capital investment in passenger rail improvements identified in the 

EIS Record of Decision. The Oklahoma Department of Transportation is a partnering state agency 

for the Study and the EIS. 

The 850-mile corridor analyzed for the Study runs north-south and roughly parallels 

Interstate Highway (IH)-35, with the northern point in Edmond, Oklahoma (i.e., northern end of the 

Oklahoma City portion of the corridor), and the southern end in south Texas, potentially in Corpus 

Christi, Brownsville, Laredo, or the Rio Grande Valley, as shown on Figure 1-1. For this service-level 

analysis, a preliminary alignment was developed to represent each EIS alternative, based on 

conceptual engineering that considered and avoided obvious physical or environmental constraints. 

These alignments were not refined to optimize performance, reduce cost, avoid specific properties 

or individual environmental resources, or for any other such considerations. If an alternative is 

selected at the service-level for further development, the above considerations would be assessed 

at the project level. A broad corridor of study with a width of 500 feet has been identified along 

each route (EIS Study Area). This EIS Study Area provides an envelope that could accommodate 

areas for associated effects, including necessary roadway shifts, grade separations, construction 

activities, and affiliated features such as stations and parking, traction-power substations, power 

lines, and maintenance-of-way facilities. The area for which data were collected is identified as the 

Study Vicinity. Typically, county-wide data were collected for counties partially or completely within 

the Study Area. 

The analysis provides quantitative information about natural ecological systems and wildlife within 

the EIS Study Area for each alternative and compares it against the No Build Alternative and other 

build alternatives in the same geographic region. The discussion of effects also provides qualitative 

differences in permanent, temporary, and direct and indirect effects that are associated with the 

service type (conventional rail, higher-speed rail, or high-speed rail) relative to the environmental 

context. However, because the 500-foot EIS Study Area does not represent the actual footprint of 

operation or construction phases, the analysis is primarily comparative, based on the presence of 

the resource within the EIS Study Area and the likelihood of effects as appropriate for this servicelevel analysis. 
TBG101414223433SCO 

1.0 Introduction

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 1-2 

Figure 1-1: Build Alternatives 
TBG101414223433SCO

1.0 Introduction

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 1-3

The build alternatives are divided into the following three geographic sections based on the key 

regional markets that could be served by passenger rail improvements:

 Northern Section: Oklahoma City to Dallas and Fort Worth 

 Central Section: Dallas and Fort Worth to San Antonio 

 Southern Section: San Antonio to South Texas 

In addition, the alternatives consist of both a route, which refers to the specific corridor that a 

potential alignment follows, and a service type, which refers to the speed or category of rail 

transportation (conventional rail, higher-speed rail, or high-speed rail). The alternatives that have 

been carried forward for analysis in the EIS, including their geographic sections, routes, and service 

types, are listed in Table 1-1.

Table 1-1: Alternatives Carried Forward for Further Evaluation

Route Service Typea 

Northern Section 

N4A CONV

Central Section 

C4A

HrSR

HSR

C4B HrSR

HSR

C4C HrSR

HSR

Southern Section 

S4 HrSR

S6 HrSR

HSR

a CONV = conventional rail (up to 79 to 90 mile per hour [mph]); HrSR 

= higher-speed rail (up to 110 to 125 mph); HSR = high-speed rail (up 

to 220 to 250 mph)

The route alternatives were based on the alignments of existing transportation networks with 

corridors potentially suitable for passenger rail operations (i.e., the existing railroad network and 

the existing interstate highway network) (the term “operations” includes maintenance of the 

facilities as well), or they were located on new alignments outside existing transportation corridors. 

Potential alignments described as “following” railway corridors share existing tracks, are located 

within an existing right-of-way, or are generally adjacent to existing tracks, depending on the service 

type. Alternatives that are outside the existing transportation corridor could have greater indirect 

effects than those located in the existing transportation corridor; for example, alternatives outside 
TBG101414223433SCO

1.0 Introduction

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 1-4

existing corridors could divide neighborhoods or wildlife communities or create a potential new 

barrier.

1.1 Service Type Descriptions 

The three service types (conventional rail, higher-speed rail, and high-speed rail) considered in this 

EIS are described below.

Conventional Rail 

Conventional rail typically includes diesel-powered, steel-wheeled trains operating on steel tracks. 

Roadway crossings may be grade-separated depending on the type of roadway and amount of 

traffic, and rail rights-of-way may be fenced. Conventional rail would be operated at speeds up to 

79 to 90 miles per hour (mph) and would mostly use existing railroad rights-of-way. For 

conventional rail alternatives, existing railroad track may be used, or in some cases, modifications 

such as double-tracking could be constructed within the existing right-of-way to accommodate 

additional trains.

Higher-Speed Rail 

Higher-speed rail is similar to conventional rail in several respects. In many cases, higher-speed rail 

trains can run on the same steel tracks that support conventional rail, but higher speeds can 

require improvements such as upgrading wooden ties with concrete ties, improving signaling, and

upgrading roadway crossings. In this case, higher-speed rail trains are assumed to be dieselpowered. Higher-speed rail would be operated at speeds up to 110 to 125 mph. Where proposed 

within an existing railroad right-of-way, a shared right-of-way with separate tracks for freight and 

passenger services would be constructed. Because of its maximum speed and because train 

frequency would be similar to conventional rail, higher-speed rail could operate on a single track 

with passing locations and would not require double-tracking. Where higher-speed rail is proposed 

outside an existing transportation corridor, the new alignment would be designed with curves and 

other features that could accommodate high-speed rail service if warranted by ridership and 

economic feasibility in the future. However, unlike high-speed rail, the design would not include 

electrification or a full double track, and some at-grade crossings would remain.

High-Speed Rail 

High-speed rail includes electric trains powered by an overhead power supply system. Train sets are 

steel wheel on steel rail, but are designed to operate at high speeds with an aerodynamic shape, 

and suspension and braking systems are designed for high-speed travel. High-speed rail would be 

operated at speeds up to 220 to 250 mph. The entire right-of-way would be fenced and fully gradeseparated. The alignment would be electrified and double-tracked. This service type could only 

reach its maximum speeds outside existing transportation corridors because existing railroad 

alignments are not compatible with the speeds required and they do not have the required space
TBG101414223433SCO

1.0 Introduction

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 1-5

for separation of freight and high-speed rail. In areas where this service type is within existing 

transportation corridors, it would operate at lower speeds.

1.2 Alternative Descriptions 

For this service-level analysis, a preliminary alignment was developed to represent each route 

alternative, based on conceptual engineering that considered obvious physical or environmental 

constraints. They are not detailed alignments that have been refined to optimize performance, 

reduce cost, avoid specific properties or individual environmental resources, or similar 

considerations, which would be assessed at the project-level phase for alternatives carried forward 

for further analysis. 

The alternatives evaluated in the service-level EIS, shown on Figure 1-1, have been developed to a 

level of detail appropriate for a service-level analysis: the route alternatives represent a potential 

corridor where rail improvements could be implemented but do not specify the precise location of 

the track alignment. When a route alternative is refined to include a service type (conventional, 

higher-speed, or high-speed rail), it is then referred to as an alternative. Alternatives in the 

Northern, Central, and Southern sections could be built as individual, stand-alone projects or in 

combination with alternatives in another section. In addition, more than one alternative in the 

Central Section and Southern Section could be built in the future because the alternatives provide 

different service types for independent destinations. Details on connecting the alternatives would 

be determined during project-level studies. 

Potential alignments are described below in terms of nearby transportation corridors and cities. 

The Southern Section alternatives include a potential extension to Monterrey, Mexico. The EIS 

evaluates alignment corridors only within the United States; however, the potential extension to 

Monterrey has been included for ridership analysis purposes, and FRA and TxDOT have initiated 

coordination with the Mexican government about the potential extension.

No Build Alternative 

The No Build Alternative would not fulfill the Program’s purpose and need but is carried forward as 

a baseline alternative against which the build alternatives are compared. The No Build Alternative 

would consist of the existing transportation network, including roadway, passenger rail, and air

travel in the Study Vicinity as well as maintenance and committed improvements to these systems.

The No Build Alternative includes existing and planned roadway, passenger rail, and air travel in the 

Study Vicinity (including operation, maintenance, and expansion). Information was collected from 

current regional transportation plans within the Study Vicinity and websites describing services 

such as train schedules. These improvements and their evaluation at this service-level stage would 

require project-specific assessment. Conducting detailed project-specific assessments at this stage 

of the program development process is not feasible, except from a cumulative analysis perspective

as included in the service-level EIS.
TBG101414223433SCO

1.0 Introduction

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 1-6

Northern Section: Oklahoma City to Dallas and Fort Worth 

Due to feasibility based on initial ridership and cost information, only one route alternative with one 

service type was considered feasible in the Northern Section: Alternative N4A with conventional rail.

1.2.2.1 Alternative N4A Conventional Rail 

Alternative N4A would begin in Edmond, Oklahoma, and follow 

the BNSF rail alignment south to Oklahoma City. The alternative 

would continue south along the BNSF rail alignment to Norman, 

Oklahoma; through Metro Junction, near Denton, Texas; and on 

to Fort Worth (as does the Heartland Flyer). From Fort Worth, 

the alternative would continue east to Dallas following the 

Trinity Railway Express (TRE) tracks. From Edmond to Dallas, the 

route would be approximately 260 miles long. Because existing 

freight traffic would not preclude passenger service along this 

section of track, the route would provide passenger rail service 

on the existing BNSF track, with potential improvements within 

the existing BNSF right-of-way.

Alternative N4A would provide several improvements over the 

existing Heartland Flyer service. Alternative N4A would increase

the number of daily round trips along this route (the Heartland 

Flyer currently offers one round trip per day), and the N4A route 

would extend from Fort Worth to Dallas without requiring a 

transfer (the Heartland Flyer service currently terminates in Fort Worth). In addition, Alternative N4A 

would provide improvements to existing station facilities and new train equipment with more 

onboard amenities, including business class available for a premium price.

Alternative N4A assumes diesel-locomotive hauled equipment running three to six daily round trips. 

Two or three of the round trips would operate on an accelerated schedule, making roughly seven 

stops, with the remaining local trains making up to 12 stops.
TBG101414223433SCO

1.0 Introduction

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 1-7

Central Section: Dallas and Fort Worth to San Antonio 

Three route alternatives, each with higher-speed and high-speed rail options, were evaluated in 

the Central Section: Alternatives C4A, C4B, and C4C.

The Central Section alternatives would provide several improvements over the existing Texas Eagle 

service in this corridor. All of the alternatives would increase the number of daily round trips along 

this route (the Texas Eagle currently offers one round trip per day). The high-speed rail options

would provide faster service between Dallas and Fort Worth and Antonio – 2 hours versus 8 hours 

for the Texas Eagle Service. In addition, the Central Section alternatives would provide 

improvements to existing station facilities and new train equipment.

1.2.3.1 Alternative C4A Higher-Speed and High-Speed Rail 

Alternative C4A would begin in Fort Worth and follow the TRE 

tracks east to Dallas. From Dallas, it would follow the BNSF 

alignment south toward Waxahachie where it would enter a new 

alignment outside existing highway and rail corridors to 

accommodate maximum operating speeds. Though outside 

existing transportation corridors, the southern portion of 

Alternative C4A would generally follow the BNSF alignment for 

about 250 miles, traveling south from Waxahachie through 

Hillsboro, Waco, Temple, Taylor, and Austin to San Antonio.

Alternative C4A Higher-Speed Rail assumes new highperformance diesel-locomotive hauled equipment running six to 

12 daily round trips. Express trains would likely make seven 

stops, and local trains would make up to 12 stops.

Alternative C4A High-Speed Rail assumes true electric-powered, 

high-speed service running 12 to 20 daily round trips. Express 

trains would likely make six stops, and local trains would make 

up to nine stops.
TBG101414223433SCO 

1.0 Introduction

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 1-8 

1.2.3.2 Alternative C4B Higher-Speed and High-Speed Rail 

Alternative C4B would serve both Fort Worth and Dallas, with 

trains following a new elevated high-speed rail alignment over 

IH-30. In Arlington (between Dallas and Fort Worth), the 

alternative would turn south to Hillsboro on an alignment 

outside existing transportation corridors. The alternative would 

then follow the same high-speed rail alignment as Alternative 

C4A from Hillsboro to San Antonio.

Alternative C4B Higher-Speed Rail assumes new highperformance diesel-locomotive hauled equipment running six to 

12 daily round trips. Express trains would likely make seven 

stops, and local trains would make up to 12 stops.

Alternative C4B High-Speed Rail assumes true electricpowered, high-speed service running 12 to 20 daily round trips. 

Express trains would likely make six stops, and local trains 

would make up to eight stops.

1.2.3.3 Alternative C4C Higher-Speed and High-Speed Rail 

Alternative C4C would follow the same potential alignment as 

Alternative C4A from Fort Worth east to Dallas and south to San 

Antonio, but would include a link from Hillsboro directly to Fort 

Worth parallel to the UPRR alignment. Service on the 

Alternative C4C route would operate in a clockwise direction, 

running from Hillsboro to Fort Worth, to Dallas, back to 

Hillsboro, and south to San Antonio in order to serve Fort Worth 

directly (while also being compatible with the general service 

for Alternative C4A).

Alternative C4C Higher-Speed Rail assumes new highperformance diesel-locomotive hauled equipment running six to 

12 daily round trips. Express trains would likely make seven 

stops, and local trains would make up to 12 stops.

Alternative C4C High-Speed Rail assumes true electric-powered 

high-speed service running 12 to 20 daily round trips. Express 

trains would likely make six stops, and local trains would make 

up to nine stops.
TBG101414223433SCO

1.0 Introduction

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 1-9

Southern Section: San Antonio to South Texas 

Two route alternatives were evaluated in the Southern Section: 

Alternative S4, with higher-speed rail, and Alternative S6, with 

higher-speed and high-speed rail options.

1.2.4.1 Alternative S4 Higher-Speed Rail 

Alternative S4 would begin in San Antonio and travel southeast 

along the UPRR alignment to George West, where it would 

continue outside existing transportation corridors to Alice. At 

Alice, the alternative would divide into three legs at a stop. The 

first leg would travel west along the Kansas City Southern (KCS) 

Railway to San Diego, Texas; it would then travel outside existing 

transportation corridors to east of Laredo in an alignment that 

would allow higher speeds and rejoin the KCS Railway to enter 

the highly developed Laredo area. The second leg would travel 

south along abandoned railroad tracks to McAllen and east to 

Harlingen and Brownsville. The third leg would travel east along 

the KCS Railway to Corpus Christi.

Alternative S4 assumes new high-performance diesel-locomotive hauled equipment running four to 

six daily round trips. Depending on corridor demand model forecasts, the primary service may be 

designated as Laredo-Alice-San Antonio and Corpus ChristieAlice-San Antonio, with a connecting feeder from Brownsville, 

Harlingen, and McAllen.

1.2.4.2 Alternative S6 Higher-Speed and High-Speed Rail 

Alternative S6 would begin in San Antonio and travel south on a 

new alignment outside existing transportation corridors to a 

station near the Laredo-Columbia Solidarity Bridge, which 

crosses the Rio Grande north of Laredo. The alternative would 

then cross on a new railway bridge to join a new rail line being 

constructed in Mexico, which would continue to Monterrey. This 

study only examines the physical effects of the U.S. component 

of this new line, but it does consider the ridership effect of such 

a connection. 

Alternative S6 Higher-Speed Rail assumes new high-performance 

diesel-locomotive hauled equipment running four to six daily 

round trips between San Antonio and Laredo, which would be the 

only U.S. stops for the alternative. If an extension from Laredo to 
TBG101414223433SCO

1.0 Introduction

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 1-10

Monterrey is added, the frequency of trips to Monterrey is assumed to be the same as those from 

San Antonio to Laredo.

Alternative S6 High-Speed Rail assumes true electric-powered, high-speed service running eight to 

12 daily round trips between San Antonio and Laredo. If an extension from Laredo to Monterrey is

added, the frequency of trips to Monterrey is assumed to be the same as those from San Antonio to 

Laredo.

Station Cities 

The study does not evaluate specific station locations, and no conclusion about the exact location 

of stations will be made as part of the service-level EIS process. However, based on ridership data 

and transit connectivity information developed as part of the alternatives analysis (TxDOT 2014), 

and based on stakeholder input, the cities in which stations would most likely be located have been 

assumed. The size and design of stations would be appropriate for the service type and the route of 

the alternative. Cities that could have stations are listed in Table 1-2.

Table 1-2: Cities with Potential Stations

Oklahoma 

Edmond Pauls Valley

Oklahoma City Ardmore

Norman

Texas 

Gainesville Austin

Fort Worth San Antonio 

Arlington Alice

Dallas Corpus Christi

Waxahachie Harlingen

Waco McAllen

Temple (also serving Killeen) Brownsville

Taylor Laredo
TBG101414223433SCO

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 2-1

2.0 Regulatory Context and Purpose 

FRA’s Procedures for Considering Environmental Impacts states: “The EIS should address both 

construction period and long-term effects of alternatives on wildlife and vegetation in the affected 

environment. Where an alternative proposes to control or modify a stream or other body of water in 

some way, it shall contain evidence of consultation with the U.S. Fish and Wildlife Service (USFWS) 

of the Department of Interior and with the agencies exercising administration over the wildlife 

resources of affected States, as required by Section 2(a) of the Fish and Wildlife Coordination Act, 

16. U.S.C. 662(a).”

The service-level EIS provides a corridor-level evaluation of reported resources in proximity to the 

build alternatives, with informal consultation with USFWS, Texas Parks and Wildlife Department 

(TPWD), and Oklahoma Department of Wildlife Conservation (ODWC). The service-level analysis also 

supports development of a memorandum of agreement between TxDOT and TPWD for Finalization 

of 1998 Memorandum of Understanding Concerning Habitat Descriptions and Mitigation. At the 

service level, the EIS does not include the detailed evaluation of individual potential resources and 

habitats.

Using database search results and informal consultation with USFWS, TPWD, and ODWC, this 

technical study identifies habitat and existing wildlife and vegetation conditions by typology within 

the EIS Study Area and identifies areas where these resources could be affected by the 

alternatives. The study also identifies existing wildlife movement corridors, natural plant 

communities, and other significant features (e.g., bird rookeries, bat caves, and prairie dog towns) 

and potential areas where the alternatives could affect the habitat or movement areas. 

TBG101414223433SCO

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 3-1

3.0 Evaluation Methods 

The methodology for this evaluation consists of a combination of qualitative and quantitative 

assessments. A qualitative level of assessment was used for general comparisons of the 

alternatives when discussing significance of effects or other issues that require a more detailed 

approach than what is warranted for this document. A detailed quantification of potential effects

and biological analysis would occur during the project-level NEPA process. General conclusions are 

generated to support the relative predicted change in effects among the alternatives. The intensity 

of an effect as a result of the build alternatives is characterized as negligible, moderate, or 

substantial compared with the No Build Alternative. For natural ecological systems and wildlife, 

these terms are defined as follows:

 Negligible intensity effects from construction and operation of an alternative are those that 

would have a slight change to natural ecological systems, wildlife corridors and assemblages 

and sensitive plant communities, and higher ecological importance/value land coverage areas, 

but are close to the existing conditions. 

 Moderate intensity effects from construction and operation of an alternative would have a 

noticeable effect on natural ecological systems, wildlife corridors and assemblages and 

sensitive plant communities, and higher ecological importance/value land coverage areas, but 

would not have an adverse residual effect on resources. 

 Substantial intensity effects would be long-term or permanent and would have a noticeable, 

inevitable effect on natural ecological systems, wildlife corridors and assemblages and sensitive 

plant communities, and higher ecological importance/value land coverage areas within the 

buffer zone.

Available information, such as land use coverage, ecoregions, wildlife corridors and assemblages, 

and sensitive plant communities, was used to assess the potential magnitude or intensity of the 

effects. As stated previously, a 500-foot-wide EIS Study Area is analyzed for each alternative. To 

evaluate the potential effects on natural ecological systems and wildlife from the construction and 

operation of the alternatives, the following acreages were quantified:

 The acreage of NLCD 2011 land cover types that intersect with the EIS Study Area. Quantitative 

and qualitative potential effects were determined using NLCD 2011 data by comparing 

acreages of developed land covers (open space, low, medium, and high) with other land cover 

types (crops, forests, wetlands, pasture, etc.) within the EIS Study Areas for each alternative. 

 The acreage of potential wildlife corridors and assemblages and sensitive plant communities 

within the EIS Study Area. Quantitative and qualitative potential effects were determined by 

assessing the acreages of wildlife corridors and assemblages and sensitive plant communities 

that intersect the EIS Study Areas for each alternative. 

To determine ecologically sensitive areas within the EIS Study Area and to analyze the overall 

potential effects on them from construction and operation of the alternatives, the EPA REAP 

methodology was used, which is a screening-level, rapid assessment tool that uses existing 
TBG101414223433SCO

3.0 Evaluation Methods

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 3-2

electronic data. REAP is further described as an ecoregional assessment, applied to the five states 

in EPA Region 6 (Arkansas, Louisiana, New Mexico, Oklahoma, and Texas). 

REAP uses 38 ecoregion sections to demonstrate ecosystem patterns at multiple scales, aiding the 

visualization of differences among ecosystems. Most ecoregions include minimally affected areas 

that can be used to define reference conditions necessary to compare affected areas. REAP divides 

18 individual measures, including land cover, contiguous size of undeveloped area, vegetation 

rarity, natural heritage rank, taxonomic richness, rare species richness, regularity of ecosystem 

boundaries, waterway obstructions (i.e., dams), road density, water quality, and air quality, from 

various databases into sublayers that compose three main layers. These main layers are diversity, 

rarity, and sustainability (EPA 2011). 

The REAP composite data and the three data layers (diversity, rarity, and sustainability) are 

designed to assess EPA Region 6 by ecoregion and to identify the optimum ecological areas for 

protection and mitigation based on ecological theory (no political boundaries or regulatory 

programs). Higher scores indicate higher ecological importance/value, which are divided into the 

following five groups: 1 (top 1 percent of scores), 10 (top 10 percent of scores), 25 (top 25 percent 

of scores), 50 (top 50 percent of scores), and 100 (all the rest of the scores). Most of the highly 

important ecological areas (1 and 10) represent the intersection of the top 10 percent for diversity, 

rarity, and sustainability. Lower REAP values (1, 10, and 25) represent the highest ecologically 

important areas. REAP scores were determined to evaluate the potential quantitative effects on 

natural ecological systems and wildlife using a similar basis of comparison across the alternatives. 
TBG101414223433SCO

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-1

4.0 Baseline/Affected Environment 

4.1 EIS Study Area 

The EIS Study Area is broadly defined by the 850-mile corridor that extends from Edmond, 

Oklahoma, in the north through Oklahoma City, Dallas, Fort Worth, Austin, and San Antonio to 

destinations in south Texas, including Laredo, Corpus Christi, and Brownsville. 

This service-level analysis used the geographic information system database to identify resources 

along the Program corridor. The extent of the analysis was limited to a 500-foot-wide buffer for each 

alternative. Therefore, the EIS Study Area is not the actual area of effect associated with 

construction and operation (the term “operation” includes maintenance) of any of the alternatives. 

For example, the construction of a passenger rail alignment can reasonably occur within a 100-foot 

right-of-way. This service-level analysis uses the EIS Study Area to determine the types of resources 

that may be affected and the relative magnitude of resources that may be affected. 

4.2 Regional Environment 

The Program encompasses a broad geographic area with semi-arid, humid subtropical, and 

modified subtropical conditions. The Program corridor generally lies along low-elevation basins and 

valleys associated with the Great Plains in the north and the Coastal Plains in the south. Land cover 

types within the Program corridor include developed land, vegetated land with open grasslands, 

agricultural land, shrubland, and forests. The climate is characterized by a regime of moderate to 

hot summer drought and winter rain. Winter rain occurs as a result of low-pressure depressions 

associated with Pacific and Arctic fronts (University of Oklahoma 2014; Texas Climate Data 2014).

In the Northern Section, annual precipitation ranges from 48 inches near Oklahoma City to 

37 inches near Dallas and Fort Worth. In the Central Section, annual precipitation ranges from 

36 inches in Waco to 34 inches in Austin. In the Southern Section, annual precipitation ranges from 

32 inches in San Antonio to 20 inches in Laredo. Precipitation is generally rain except from Dallas 

and Fort Worth to Oklahoma where snowfall may occur. The daily high temperature ranges from 50 

to 94 degrees Fahrenheit (°F) in the Northern Section to 67 to 100°F in the Southern Section. 

However, temperatures over 100°F are common in summer throughout the entire EIS Study Area

(U.S. Climate Data 2014).

4.3 Regulatory Environment 

This service-level EIS includes a corridor-level evaluation of reported resources in proximity to the 

build alternatives, not a detailed evaluation of individual resources and habitats. No specific federal 

or state laws or regulations apply to natural ecological systems and wildlife, in general. However, a 

number of federal and state legislation and regulations pertain to wetlands and threatened and 

endangered species. Aquatic habitats are protected under regulations that limit their use or 

destruction. Section 404 of the Clean Water Act (CWA) requires authorization for activities that

include placement of dredge and fill material or mechanized land clearing, ditching, draining, 

channelization or other excavation activities into the waters of the U.S., including wetlands. A 
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-2

detailed discussion of the aquatic habitats protected under Section 404 of the CWA is included in 

the Water Quality Technical Study, included as Appendix F of this Draft EIS.

Plant and animal species whose populations have declined to a point where extinction is imminent 

have legal protection under federal and state laws. Section 7 of the Endangered Species Act of 

1973 regulates federally listed threatened and endangered species and designated critical

habitats. Section 4 (listing of a species, critical habitat, and recovery), Section 9 (prohibited acts),

and Section 10 (permitting and conservation plans) also provide legal protection. USFWS and the 

National Marine Fisheries Service have authority to identify species in danger of extinction and 

provide for their management and protection. A detailed discussion of threatened and endangered 

species is included in the Threatened and Endangered Species Technical Study, included as 

Appendix H of this Draft EIS.

The potential effects on natural ecological systems and wildlife were analyzed in accordance with 

the National Environmental Policy Act (NEPA) of 1969, as amended (42 United States Code [U.S.C.]

§4321, et seq.), the Council on Environmental Quality regulations for implementing the procedural 

provisions of NEPA (40 Code of Federal Regulations Parts 1500-1508), FRA policies and 

procedures for considering environmental impacts, and the TxDOT Environmental Manual (TxDOT 

2004).

4.4 U.S. EPA Level III Ecoregions 

The U.S. Environmental Protection Agency (EPA) Office of Research and Development has 

developed a system of “ecoregion” definitions that denote areas of general similarity in ecosystems 

and in the type, quality, and quantity of environmental resources. EPA ecoregions serve as a spatial 

framework for the research, assessment, management, and monitoring of ecosystems and 

ecosystem components. The approach was based on the premise that ecological regions can be 

identified through the analysis of patterns of biotic and abiotic phenomena, including geology, 

physical geography, vegetation, climate, soils, land use, wildlife, and hydrology. The relative 

importance of each characteristic varies from one ecological region to another. A Roman numeral 

hierarchical scheme was adopted for different levels for ecological regions. Level I is the coarsest 

level, dividing North America into 15 ecological regions. Level II divides the continent into 50 

regions. At Level III, the continental United States contains 104 regions (EPA 2014). Level IV 

ecoregions are further subdivisions of Level III ecoregions. For this service-level analysis, Level III 

ecoregions were used. Level III ecoregion data are based largely on plant community types; 

therefore, they can be used to describe general vegetation characteristics throughout the EIS Study 

Area and identify potential effects associated with the alternatives. EPA Level III ecoregions within 

the EIS Study Area are summarized below and shown on Figures 4-1 through 4-3.
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-3

Figure 4-1: U.S. EPA Level III Ecoregions – Northern Section Alternative
TBG101414223433SCO 

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-4 

Figure 4-2: U.S. EPA Level III Ecoregions – Central Section Alternatives
TBG101414223433SCO 

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016 

Natural Ecological Systems and Wildlife Technical Study Page 4-5 

Figure 4-3: U.S. EPA Level III Ecoregions – Southern Section Alternatives
TBG101414223433SCO 

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-6 

Central Great Plains 

Once a grassland with scattered low trees and shrubs in the south, much of the Central Great 

Plains ecological region is now cropland, with the eastern boundary of the region marking the 

eastern limits of the major winter wheat growing area of the United States. Subsurface salt deposits 

and leaching contribute to high salinity in streams in the Central Great Plains ecoregion. The 

Central Great Plains ecoregion is identified within the EIS Study Area for Alternative N4A near 

Edmond and Norman, Oklahoma. 

Cross Timbers 

The Cross Timbers ecoregion is a transition area between what was once prairie and is now winter 

wheat growing regions to the west, and the forested low mountains or hills of eastern Oklahoma 

and Texas. The region does not possess the arability and suitability for crops like corn and 

soybeans that are common in the Central Irregular Plains to the northeast. Transitional cross

timbers (Little Bluestem grassland with scattered blackjack oak and post oak trees) is the native 

vegetation, and rangeland and pastureland compose the predominant land cover types, with areas 

of woodland. Oil extraction has been a major activity in this region for more than 80 years. The 

majority of the EIS Study Area for Alternative N4A extends within the Cross Timbers ecoregion south 

of Norman to Fort Worth. The Cross Timbers ecoregion is also identified within the EIS Study Areas 

for Alternatives C4A, C4B, and C4C, where these alternatives extend near Fort Worth. 

East Central Texas Plains 

Also called the Post Oak Savanna or the Claypan Area, the East Central Texas Plains region consists 

of irregular plains, which was originally covered by post oak savanna vegetation, in contrast to the 

more open prairie-type regions to the north, south, and west and the pine forests to the east. The 

boundary with the South Central Plains ecoregion is a subtle transition of soils and vegetation.

Many areas have a dense, underlying clay pan affecting water movement and available moisture for 

plant growth. The bulk of this region is used for pasture and range. The East Central Texas Plains 

ecoregion is identified within the EIS Study Area for Alternative S4, where this alternative extends 

south of San Antonio. 

Southern Texas Plains/Interior Plains and Hills with Xerophytic Shrub and Oak 

Forest 

The rolling to moderately dissected South Texas Plains/Interior Plains region was once covered with 

grassland and savannah vegetation that varied during wet and dry cycles. Following long continued 

grazing and fire suppression, thorny brush, such as mesquite, is now the predominant vegetation 

type. Also known as the Tamualipan Thornscrub, or the “brush c,” the subhumid to dry region has 

its greatest extent in Mexico. It is generally lower in elevation with warmer winters than the 

Chihuahuan Deserts to the northwest, and it contains a high and distinct diversity of plant and 

animal life. The majority of the EIS Study Area for Alternative S6 extends within this ecoregion south 

of San Antonio to its termination near Laredo. This ecoregion is also identified within the EIS Study 
TBG101414223433SCO 

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016 

Natural Ecological Systems and Wildlife Technical Study Page 4-7 

Area for Alternative S4, where this alternative extends south from San Antonio to Alice and

continues from Alice to its termination point near Laredo. 

Texas Blackland Prairies 

The Texas Blackland Prairies form a disjunct ecological region, distinguished from surrounding 

regions by fine-textured, clayey soils and predominantly prairie natural vegetation. This region 

contains a higher percentage of cropland than adjacent regions, and pasture and forage production 

for livestock is common. The majority of the EIS Study Areas for Alternatives C4A, C4B, and C4C, 

extending from Dallas to San Antonio, are within the Texas Blackland Prairies ecoregion. The Texas 

Blackland Prairies ecoregion is also identified within the EIS Study Areas for Alternatives S4 and S6, 

where these two alternatives extend near San Antonio. 

Western Gulf Coastal Plain 

The principal distinguishing characteristics of the Western Gulf Coastal Plain are its relatively flat 

coastal plain topography and mainly grassland potential natural vegetation. Inland from this region, 

the plains are older and more irregular and have the potential for mostly forest or savannah-type 

vegetation. Largely because of these characteristics, a higher percentage of the land is in cropland 

than in bordering ecological regions. Urban and industrial land uses have expanded greatly in 

recent decades, and oil and gas production is common. The Western Gulf Coastal Plain ecoregion is 

identified within the EIS Study Area for Alternative S4, where this alternative extends south from 

Alice to McAllen and onto Brownsville. 

4.5 National Land Cover Database – Land Cover Types 

The National Land Cover Database (NLCD) is created through a cooperative project by the MultiResolution Land Characteristics (MRLC) Consortium. The MRLC Consortium is a partnership of 

federal agencies, consisting of EPA, USFWS, U.S. Geological Survey, National Oceanic and 

Atmospheric Administration, U.S. Department of Agriculture, U.S. Forest Service, National Park 

Service, Bureau of Land Management, and the U.S. Department of Agriculture Natural Resources 

Conservation Service. NLCD 2011, the most recent version of the database, provides the capability 

to assess national land cover changes and trends across the United States from 2001 to 2011. As 

with previous versions of the NLCD (1992 and 2001), NLCD 2011 uses a 16-class land cover 

classification scheme that has been applied consistently across the United States at a spatial 

resolution of 30 meters (MRLC 2011). The NLCD is used in this analysis to describe general 

vegetation characteristics throughout the EIS Study Area, to compare areas of developed versus 

non-developed land covers by providing a spatial reference and data for characteristics of the land 

surface (developed, agriculture, forest, etc.), and to identify potential effects associated with the 

alternatives. The NLCD 2011 land cover types within the EIS Study Area are summarized below. The 

acres of potential land cover types and their percentages of total area within the EIS Study Areas 

are shown in Tables 3-1 through 3-3 for Alternative N4A (conventional rail); Alternatives C4A, C4B, 

and C4C (higher- and high-speed rail); and Alternatives S4 (higher-speed rail) and S6 (higher- and 

high-speed rail), respectively. 
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-8

Water 

4.5.1.1 Open Water 

The NLCD open water land cover type includes areas of open water, generally with less than 

25 percent cover of vegetation or soil. 

Developed 

4.5.2.1 Developed, High Intensity 

The NLCD developed, high intensity land cover type includes areas that are highly developed, where 

people reside or work in high numbers. Examples include apartment complexes, row houses, and 

commercial/industrial activities. Impervious surfaces account for 80 to 100 percent of the total 

cover.

4.5.2.2 Developed, Medium Intensity 

The NLCD developed, medium intensity land cover type includes areas with a mixture of 

constructed materials and vegetation. Impervious surfaces account for 50 to 79 percent of the total 

cover. These areas most commonly include single-family housing units.

4.5.2.3 Developed, Low Intensity 

The NLCD developed, low intensity land cover type includes areas with a mixture of constructed 

materials and vegetation. Impervious surfaces account for 20 to 49 percent of total cover. These 

areas most commonly include single-family housing units.

4.5.2.4 Developed, Open Space 

The NLCD developed, open space land cover type includes areas with a mixture of constructed 

materials, but mostly vegetation in the form of lawn grasses. Impervious surfaces account for less 

than 20 percent of total cover. These areas most commonly include large-lot single-family housing 

units, parks, golf courses, and vegetation planted in developed settings for recreation, erosion 

control, or aesthetic purposes.

Barren 

4.5.3.1 Barren Land (Rock/Sand/Clay) 

The NLCD barren land cover type includes areas of bedrock, desert pavement, steep slopes, slides, 

volcanic material, glacial debris, sand dunes, strip mines, gravel pits, and other accumulations of 

earthen material. Generally, vegetation accounts for less than 15 percent of total cover.
TBG101414223433SCO 

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016 

Natural Ecological Systems and Wildlife Technical Study Page 4-9 

Forest 

4.5.4.1 Deciduous Forest 

The NLCD forest (deciduous) land cover type includes areas dominated by trees generally greater 

than 5 meters tall and greater than 20 percent of total vegetation cover. More than 75 percent of 

the tree species shed foliage simultaneously in response to seasonal change.

4.5.4.2 Evergreen Forest 

The NLCD forest (evergreen) land cover type includes areas dominated by trees generally greater 

than 5 meters tall and greater than 20 percent of total vegetation cover. More than 75 percent of 

the tree species maintain their leaves all year. Canopy is never without green foliage. 

4.5.4.3 Mixed Forest 

The NLCD forest (mixed) land cover type includes areas dominated by trees generally greater than 

5 meters tall and greater than 20 percent of total vegetation cover. Neither deciduous nor 

evergreen species are greater than 75 percent of total tree cover. 

Shrubland 

4.5.5.1 Shrub/Scrub 

The NLCD shrubland (shrub/scrub) land cover type includes areas dominated by shrubs less than 

5 meters tall with shrub canopy generally greater than 20 percent of total vegetation. This land 

cover type includes true shrubs, young trees in an early successional stage, and trees stunted from 

environmental conditions.

Herbaceous 

4.5.6.1 Grassland/Herbaceous 

The NLCD herbaceous (grassland/herbaceous) land cover type includes areas dominated by 

gramanoid or herbaceous vegetation generally greater than 80 percent of total vegetation. These 

areas are not subject to intensive management such as tilling, but can be used for grazing.

Planted/Cultivated 

4.5.7.1 Pasture/Hay 

The NLCD planted/cultivated (pasture/hay) land cover type includes areas of grasses, legumes, or 

grass-legume mixtures planted for livestock grazing or the production of seed or hay crops, typically 

on a perennial cycle. Pasture/hay vegetation accounts for greater than 20 percent of total 

vegetation. 
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-10

4.5.7.2 Cultivated Crops 

The NLCD planted/cultivated (cultivated crops) land cover type includes areas used for the 

production of annual crops, such as corn, soybeans, vegetables, tobacco, and cotton, and perennial 

woody crops such as orchards and vineyards. Crop vegetation accounts for greater than 20 percent

of total vegetation. This land cover type also includes land being actively tilled.

Wetlands 

4.5.8.1 Woody Wetlands 

The NLCD wetlands (woody) land cover type includes areas where forest or shrubland vegetation 

accounts for greater than 20 percent of vegetative cover and the soil or substrate is periodically 

saturated with or covered with water.

4.5.8.2 Emergent Herbaceous Wetlands 

The NLCD wetlands (emergent herbaceous) land cover type includes areas where perennial 

herbaceous vegetation accounts for greater than 80 percent of vegetative cover and the soil or 

substrate is periodically saturated with or covered with water.

As shown in Table 4-1, approximately 46 percent (6,947 acres) of the 15,108 acres of the 

Alternative N4A EIS Study Area is composed of developed land cover types (high, medium, and low 

intensity or open space). The remaining 54 percent (8,161 acres) is composed of non-developed 

land cover types, with grasslands composing 30 percent, forest composing 12 percent, cultivated 

crops composing 6 percent, pasture composing 5 percent, and open water composing 1 percent. 

Less than 1 percent of the EIS Study Area is composed of wetlands and shrubland/scrub. 

Table 4-1: Acres of Potential Land Cover Types within EIS Study Area – Northern 

Alternative N4A Conventional Rail

Land Cover Type 

Alternative 

N4A (CONV) 

Acres of Land Cover Types 

within EIS Study Area Total Area of EIS Study Area 

Developed, High Intensity 1,249

Developed, Low Intensity 2,046 46%

Developed, Medium Intensity 1,625

Developed, Open Space 2,027

Barren Land (Rock/Sand/Clay) 53 <1%

Cultivated Crops 960 6%

Deciduous Forest 1,748 12%

Emergent Herbaceous Wetlands 8 <1%

Evergreen Forest 15 <1%

Grassland/Herbaceous 4,465 30%
TBG101414223433SCO 

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016 

Natural Ecological Systems and Wildlife Technical Study Page 4-11 

Land Cover Type 

Alternative 

N4A (CONV) 

Acres of Land Cover Types 

within EIS Study Area Total Area of EIS Study Area 

Mixed Forest 0 -

Open Water 120 1%

Pasture/Hay 783 5%

Shrub/Scrub 2 <1%

Woody Wetlands 7 <1%

Source: MRLC (2011). 

As shown in Table 4-2, approximately 38 percent (7,564 acres) of the 20,129 acres of the EIS 

Study Area for Alternative C4A is composed of developed land cover types. The remaining 62

percent (12,565 acres) is composed of non-developed land cover types, with grasslands composing

21 percent, cultivated crops composing 15 percent, shrub/scrub composing 9 percent, and forest

and pasture composing 7 percent. Wetlands (emergent herbaceous and woody) and open water 

compose about 2 percent and less than 1 percent, respectively. 

As shown in Table 4-2, approximately 36 percent (6,642 acres) of the 18,675 acres of the EIS 

Study Area for Alternative C4B is composed of developed land cover types. The remaining area is 

composed of non-developed land cover types, with grasslands composing 21 percent, cultivated 

crops composing 17 percent, shrub/scrub and pasture composing 9 percent each, and forest

composing 5 percent. Wetlands and open water compose 2 and less than 1 percent, respectively. 

Approximately 38 percent (9,123 acres) of the 23,713 acres of the EIS Study Area for Alternative 

C4C is composed of developed land cover types. The remaining area is composed of grasslands 

(23 percent), cultivated crops (14 percent), forest (8 percent), shrub/scrub (7 percent), pasture 

(6 percent), and wetlands (2 percent). Less than 1 percent is composed of open water. 

Table 4-2: Acres of Potential Land Cover Types – Central Section Alternatives 

Land Cover Type 

Alternative 

C4A (HrSR and HSR) C4B (HrSR and HSR) C4C (HrSR and HSR) 

Acres of 

Land Cover 

Types 

within EIS 

Study Area 

Total Area 

of EIS Study 

Area 

Acres of 

Land Cover 

Types 

within EIS 

Study Area 

Total Area 

of EIS Study 

Area 

Acres of 

Land Cover 

Types 

within EIS 

Study Area 

Total Area 

of EIS Study 

Area 

Developed, High Intensity 1,347

38% 

1,318

36% 

1,533

38% 

Developed, Low Intensity 1,667 1,374 2,108
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-12

Land Cover Type 

Alternative 

C4A (HrSR and HSR) C4B (HrSR and HSR) C4C (HrSR and HSR) 

Acres of 

Land Cover 

Types 

within EIS 

Study Area 

Total Area 

of EIS Study 

Area 

Acres of 

Land Cover 

Types 

within EIS 

Study Area 

Total Area 

of EIS Study 

Area 

Acres of 

Land Cover 

Types 

within EIS 

Study Area 

Total Area 

of EIS Study 

Area 

Developed, Medium 

Intensity

1,809 1,810 2,080

Developed, Open Space 2,741 2,140 3,401

Barren Land 

(Rock/Sand/Clay)

48 <1% 30 <1% 60 <1%

Cultivated Crops 3,013 15% 3,252 17% 3,350 14%

Deciduous Forest 1,284 6% 812 4% 1738 7%

Emergent Herbaceous 

Wetlands 

18 <1% 10 <1% 18 <1%

Evergreen Forest 261 1% 237 1% 264 1%

Grassland/Herbaceous 4,274 21% 3,886 21% 5,415 23%

Mixed Forest 63 <1% 63 <1% 63 <1%

Open Water 80 <1% 59 <1% 84 <1%

Pasture/Hay 1,404 7% 1,602 9% 1,453 6%

Shrub/Scrub 1,720 9% 1,716 9% 1,728 7%

Woody Wetlands 400 2% 366 2% 418 2%

Source: MRLC (2011).

As shown in Table 4-3, approximately 32 percent (7,998 acres) of the 25,191 acres of the EIS 

Study Area for Alternative S4 is composed of developed land cover types. The remaining area is 

composed of non-developed land cover types, with shrub/scrub composing 34 percent, pasture 

composing 12 percent, and grassland and cultivated crops composing 9 percent each. Wetlands 

compose about 2 percent, and forests compose about 1 percent.

As shown in Table 4-3, approximately 8 percent (701 acres) of the 8,666 acres of the EIS Study 

Area for Alternative S6 is composed of developed land cover types. The majority of the land 

coverage of the EIS Study Area for Alternative S6 is composed of non-developed land cover types, 

consisting of shrub/scrub (44 percent), grasslands (20 percent), cultivated crops (14 percent), 

pasture (7 percent), wetlands (3 percent), and forest (3 percent). 
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-13

Table 4-3: Acres of Potential Land Cover Types within EIS Study Area – Southern 

Section

Land Cover Type 

Alternative 

S4 (HrSR) S6 (HrSR and HSR) 

Acres of Land 

Cover Types 

within EIS Study 

Area 

Total Area of 

EIS Study Area 

Acres of Land 

Cover Types 

within EIS Study 

Area 

Total Area of 

EIS Study Area 

Developed, High Intensity 776

32%

84

8%

Developed, Low Intensity 2,888 202

Developed, Medium 

Intensity

2,019 97

Developed, Open Space 2,315 318

Barren Land 

(Rock/Sand/Clay)

260 1% 108 1%

Cultivated Crops 2,174 9% 1,177 14%

Deciduous Forest 340 1% 112 1%

Emergent Herbaceous 

Wetlands 

64 <1% 9 <1%

Evergreen Forest 41 <1% 58 1%

Grassland/Herbaceous 2,330 9% 1,729 20%

Mixed Forest 24 <1% 52 1%

Open Water 45 <1% 11 <1%

Pasture/Hay 2,948 12% 578 7%

Shrub/Scrub 8,574 34% 3,852 44%

Woody Wetlands 396 2% 279 3%

Source: MRLC (2011).

4.6 Wildlife Corridors and Assemblages and Sensitive Plant Communities 

The analysis of wildlife corridors and assemblages and sensitive plant communities used the 2011 

Environmental Occurrences for Federal and State Listed and Tracked Threatened, Endangered, 

and Rare Species spatial dataset. This dataset was acquired from the TPWD Texas Natural Diversity 

Database that was originally clipped for the TxDOT High-Speed Intercity Passenger Rail IH-35 

Corridor Constraints Update to meet High-Speed Intercity Passenger Rail project planning needs.

Based on the spatial dataset, one sensitive terrestrial plant community, Little Bluestem-Indiangrass 

series (Schizachyrium scoparium-sorghastrum nutans series), is located within the EIS Study Area.

The Little Bluestem-Indiangrass series plant community is an upland prairie, native tall grassland,

climax plant community that contains native grasses and forbs. Much of north-central Texas in the 
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-14

Blackland Prairies, Fort Worth Prairie, Rolling Plains, Edwards Plateau, and Lampasas Cut Plain 

ecoregions, was historically native prairies or savannahs. Native prairie areas were also within the 

East and West Cross Timbers ecoregions. Few native prairie sites remain today, although there are 

extensive grasslands on many private ranches in the northern portion of the Fort Worth Prairie and 

in the Lampasas Cut Plain, West Cross Timbers, Edwards Plateau, and Rolling Plains ecoregions

(TPWD 2014).

Based on the same dataset, one type of animal assemblage, identified as a “rookery,” is located 

within the EIS Study Area. Rookeries, or breeding grounds of colony-forming species, are important 

to an ecosystem as they are home to migratory and resident wading birds and shorebirds. No other

natural plant communities or other significant features (e.g., bird rookeries, bat caves, prairie dog 

towns) are within the EIS Study Area.

Approximately 85 acres of animal assemblage area (rookeries) are located within the Alternative 

N4A EIS Study Area. No other wildlife corridors and assemblages or sensitive plant communities 

were identified within the Alternative N4A EIS Study Area. As shown on Figure 4-4, the rookery is 

represented by a relatively small circular area, just north of Fort Worth. 

Approximately 107, 66, and 107 acres of rookery animal assemblage are within the EIS Study 

Areas for Alternative C4A, C4B, and C4C, respectively. Approximately 628 acres of Little BluestemIndiangrass series terrestrial community are within the EIS Study Areas for Alternative C4A, C4B, 

and C4C. As shown on Figures 4-5 and 4-6, the animal assemblages and special terrestrial 

communities are, for the most part, in the portions of each alternative outside of existing 

transportation corridors.

Approximately 678 acres of Little Bluestem-Indiangrass series terrestrial community are within the 

EIS Study Area for Alternative S4. No wildlife corridors and assemblages or other sensitive plant 

communities were identified within the EIS Study Area. As shown on Figures 4-7 through 4-10, the 

large area of Little Bluestem-Indiangrass series terrestrial community is in Brooks County, in an 

area of Alternative S4 that would be constructed on an abandoned rail.
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-15

Figure 4-4: Wildlife Corridors/Assemblages and Communities – Northern Section 

Alternative

(Note that wildlife corridors and assemblages are included in the figure as Animal Assemblages.)
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-16

Figure 4-5: Wildlife Corridors/Assemblages and Communities – Central Section 

Alternatives

(Note that wildlife corridors and assemblages are included in the figure as Animal Assemblages.)
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-17

Figure 4-6: Wildlife Corridors/Assemblages and Communities – Central Section 

Alternatives

(Note that wildlife corridors and assemblages are included in the figure as Animal Assemblages.)
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-18

Figure 4-7: Wildlife Corridors/Assemblages and Communities – Southern Section 

Alternatives

(Note that wildlife corridors and assemblages are included in the figure as Animal Assemblages.)
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-19

Figure 4-8: Wildlife Corridors/Assemblages and Communities – Southern Section 

Alternatives

(Note that wildlife corridors and assemblages are included in the figure as Animal Assemblages.)
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-20

Figure 4-9: Wildlife Corridors/Assemblages and Communities – Southern Section 

Alternatives

(Note that wildlife corridors and assemblages are included in the figure as Animal Assemblages.)
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-21

Figure 4-10: Wildlife Corridors/Assemblages and Communities – Southern Section 

Alternatives

(Note that wildlife corridors and assemblages are included in the figure as Animal Assemblages.)
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-22

4.7 Regional Ecological Assessment Protocol (REAP) Composite Score 

As shown in Table 4-4, potentially 10 percent (1,535 acres) of the total land coverage of the EIS 

Study Area for Alternative N4A is composed of higher ecological importance/value land coverage 

areas (Ecological Importance Rankings of 1, 10, and 25)1. As shown on Figures 4-11 and 4-12, the 

lands with higher ecological importance are just south of Norman, near Murray County. All other

areas of Alternative N4A consist predominantly of lower ecological value land types.

Table 4-4: Acres of Potential REAP Composite Ranking Land Coverages – Northern 

Section 

Ecological 

Importance Rank 

Alternative 

N4A (CONV) 

Acres of Potential REAP 

Ecological Importance 

Ranking Types within EIS 

Study Area 

Total Area of EIS Study Area 

(High Value versus All Other 

Land Types) 

1 100

10 665 10% (1,535 acres)

25 770

50 1,829 90% (13,572 acres) 100 11,743

Total (acres) 15,107 - 

Source: EPA (2011).

As shown in Table 4-5, potentially 18 percent (3,537 acres), 18 percent (3,328 acres), and 

15 percent (3,556 acres) of the total acreage of the EIS Study Areas for Alternatives C4A, C4B, and 

C4C, respectively, are composed of higher ecological importance/value land coverage areas 

(Ecological Importance Rankings of 1, 10, and 25). As shown on Figures 4-13 and 4-14, the 

majority of lands with higher ecological importance are in the portions of Alternatives C4A, C4B, and 

C4C outside existing transportation corridors, in areas just south of McGregor and through Temple, 

and in areas east of Austin and as the corridors pass through Guadalupe County. Areas of 

Alternatives C4A, C4B, and C4C that consist of predominantly lower ecological value land types are 

near Dallas and Fort Worth, where the alternatives would either follow the existing TRE tracks to 

Dallas and continue on the BNSF alignment, or follow a new elevated high-speed alignment in the 

IH-30 median to Arlington.

 1 To determine ecologically sensitive areas within the EIS Study Area and to analyze the overall potential effects on 

them from construction and operation of the alternatives, the EPA REAP methodology was used, which is a screeninglevel, rapid assessment tool that uses existing electronic data.
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-23

Figure 4-11: REAP Composite Scores – Northern Section Alternative
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-24

Figure 4-12: REAP Composite Scores – Northern Section Alternative
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-25

Figure 4-13: REAP Composite Scores – Central Section Alternatives
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-26

Figure 4-14: REAP Composite Scores – Central Section Alternatives
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-27

Table 4-5: Acres of Potential REAP Composite Ranking Land Coverages – Central 

Section 

Ecological 

Importance 

Rank 

Alternative 

C4A (HrSR and HSR) C4B (HrSR and HSR) C4C (HrSR and HSR) 

Acres of 

Potential REAP 

Ecological 

Importance 

Ranking Types 

within EIS Study 

Area 

Total Area of EIS 

Study Area 

(High Value vs. 

All Other Land 

Types) 

Acres of 

Potential REAP 

Ecological 

Importance 

Ranking Types 

within EIS 

Study Area 

Total Area of 

EIS Study 

Area 

(High Value 

vs. All Other 

Land Types) 

Acres of 

Potential REAP 

Ecological 

Importance 

Ranking Types 

within EIS Study 

Area 

Total Area of 

EIS Study 

Area 

(High Value 

vs. All Other 

Land Types) 

1 32

18% (3,537 

acres)

32

18% (3,328 

acres)

32

15% (3,556 

acres)

10 1,884 1,839 1,884

25 1,621 1,457 1,640

50 3,407

82% (16,591 

acres)

2,727 82%

(15,347 

acres)

3,613 85%

(20,158 

acres)

100 13,184 12,621 16,546

Total (acres) 20,128 - 18,675 - 23,714 - 

Source: EPA (2011).

As shown in Table 4-6, potentially 15 percent (3,659 acres) of the total acreage of the EIS Study 

Area for Alternative S4 is composed of higher ecological importance/value land coverage areas 

(Ecological Importance Rankings of 1, 10, and 25). Potentially 21 percent (1,796 acres) of the total 

acreage of the EIS Study Area for Alternative S6 is composed of higher ecological importance/value 

land coverage areas. As shown on Figures 4-15 through 4-18, most lands with higher ecological 

importance for Alternative S4 are near Brooks, Live Oak, Duval, and Webb counties.

Table 4-6: Acres of Potential REAP Composite Ranking Land Coverages – Southern 

Section 

Ecological 

Importance 

Rank 

Alternative 

S4 (HrSR) S6 (HrSR and HSR) 

Acres of Potential REAP 

Ecological Importance 

Ranking Types within EIS 

Study Area 

Total Area of EIS 

Study Area 

(High Value vs. All 

Other Land Types) 

Acres of Potential REAP 

Ecological Importance 

Ranking Types within EIS 

Study Area 

Total Area of EIS 

Study Area 

(High Value vs. All 

Other Land Types) 

1 21

15% (3,659 acres)

31

10 1,088 538 21% (1,796 acres)

25 2,550 1,227

50 4,589

85% (21,533 acres) 2,38979% (6,901 acres) 100 16,943 4,469

Total (acres) 25,192 - 8,653 - 

Source: EPA (2011).
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-28

Figure 4-15: REAP Composite Scores – Southern Section Alternatives
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-29

Figure 4-16: REAP Composite Scores – Southern Section Alternatives
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-30

Figure 4-17: REAP Composite Scores – Southern Section Alternatives
TBG101414223433SCO

4.0 Baseline/Affected Environment

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 4-31

Figure 4-18: REAP Composite Scores – Southern Section Alternatives

TBG101414223433SCO

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 5-1

5.0 Effects on Natural Ecological Systems and Wildlife 

The potential effects and their relative intensity from the construction and operation (including 

maintenance) of the build alternatives and No Build Alternative on natural ecological systems and 

wildlife within the EIS Study Area are presented in this section. It is important to note that alignment 

routes in the Northern, Central, or Southern sections could be built alone, or combined with other 

section routes. More than one alternative in the Central or Southern sections could also be built in 

the future as the alternatives provide different service options for the independent destinations. 

Details about how the alternatives might connect would be analyzed at the project-level EIS phase. 

Therefore, this study does not summarize effects for the entire route from Oklahoma to 

Laredo/Brownsville. Rather, this analysis provides information about each individual build

alternative compared against the No Build Alternative and, as applicable, compared with other

alternatives for that same section.

Specific station locations were not analyzed as part of this service-level analysis. In general, 

stations are constructed in populated areas (urbanized city or suburban city) and not in 

undeveloped or rural locations. Therefore, potential effects associated with the construction and 

operation of stations on natural ecosystems and wildlife would not likely be more than the potential 

resources identified during the service-level analysis.

5.1 No Build Alternative 

The No Build Alternative would not fulfill the Program’s purpose and need, but is carried forward as 

a baseline alternative against which the build alternatives are compared. The No Build Alternative 

would consist of the existing transportation network, including roadway, passenger rail, and air 

travel in the Study Vicinity, as well as maintenance and planned improvements to these systems. 

These improvements and their evaluation at this service-level stage would require project-specific 

detail and assessment, which is not available. Anticipated natural ecological systems and wildlife 

effects on the EIS Study Area under the No Build Alternative would be consistent with existing and 

planned transportation system uses and potential expansions. 

National Land Cover Database – Land Cover Types 

Under the No Build Alternative, construction of the Program would not occur. Therefore, no 

significant effects on NLCD land cover types would be anticipated.

Wildlife Corridors and Assemblages and Sensitive Plant Communities 

Under the No Build Alternative, construction of the Program would not occur. Therefore, no 

significant effects on wildlife corridors and assemblages or sensitive plant communities would be 

anticipated.
TBG101414223433SCO

5.0 Effects on Natural Ecological Systems and Wildlife

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 5-2

REAP Composite Scores 

Under the No Build Alternative, construction of the Program would not occur. Therefore, no 

significant effects on higher ecological importance/value land coverage areas (Ecological 

Importance Rankings of 1, 10, and 25) would be anticipated.

5.2 Northern Section: Oklahoma City to Dallas and Fort Worth 

This section provides potential effects and their relative intensity from the construction and 

operation of the build alternative in the Northern Section on natural ecological systems and wildlife.

National Land Cover Database – Land Cover Types 

Alternative N4A would follow the BNSF rail alignment and the existing TRE tracks. The percentage of 

total non-developed land cover types within the Alternative N4A EIS Study Area would represent a 

negligible effect on undeveloped land when compared with the No Build Alternative because the 

majority of construction would occur within existing right-of-way. The potential operations effects 

associated with Alternative N4A with regard to developed land covers within the EIS Study Area 

would be considered negligible as the service would operate within existing rights-of-way. 

Wildlife Corridors and Assemblages and Sensitive Plant Communities 

The potential effects associated with construction of Alternative N4A would be negligible when 

compared with the No Build Alternative because Alternative N4A would be constructed within 

existing rights-of-way and would not be anticipated to have new effects on sensitive communities.

Operations effects for Alternative N4A would be moderate because this alternative would not likely 

be fenced, making wildlife movement vulnerable to an increased risk for strikes from the additional 

rail traffic along the route. Such effects would have a noticeable effect on wildlife, but the effects 

could be reduced by the use of best management practices (BMPs).

REAP Composite Scores 

The lands with higher ecological importance are just south of Norman, near Murray County, as the 

route passes through Love and Grayson counties. All other areas of Alternative N4A consist 

predominantly of lower ecological value land types; in these areas, the alternative would not 

substantially affect areas of higher ecological importance. The potential effects associated with 

construction and operation of Alternative N4A Conventional on higher ecological importance/value 

and land coverage types would be negligible, as most effects from this alternative would be during 

construction within existing rights-of-way that were disturbed by prior rail development. 

Potential Construction Effects 

Short-term effects on terrestrial biological resources and habitats would be anticipated as a result 

of constructing Alternative N4A and could include temporary to long-term effects on vegetation from 

clearing for construction equipment and the stockpiling of soil, ballast, or other construction 
TBG101414223433SCO

5.0 Effects on Natural Ecological Systems and Wildlife

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 5-3

materials. Additionally, short-term noise, vibration, and air pollution from construction equipment 

and activities could affect nearby terrestrial habitats and their wildlife. However, such effects would 

negligible given the anticipated size of these potential construction effect areas compared with the 

amount of undisturbed habitat that would remain in the area. In addition, limited permanent effects

would be expected as Alternative N4A would follow existing rail alignments. 

Potential Operations Effects 

Alternative N4A would follow the BNSF rail alignment and the existing TRE tracks. Potential 

operations effects would be considered moderate when compared with the No Build Alternative as 

Alternative N4A would not likely be fenced, making wildlife movement vulnerable to an increased 

risk for strikes from the additional rail traffic along the route. Such effects would have a noticeable 

effect on wildlife, but the effects could be mitigated by BMPs during operation. 

5.3 Central Section: Dallas and Fort Worth to San Antonio 

This section provides potential effects and their relative intensity from the construction and 

operation of the build alternatives in the Central Section on natural ecological systems and wildlife. 

The effect intensities would be the same between the higher-speed and high-speed alternatives;

however, slight differences for operations-related effects on wildlife corridors/assemblages and 

sensitive plant communities are explained below and presented in Table 5-1.

National Land Cover Database – Land Cover Types 

The percentages of total non-developed land covers within the EIS Study Areas for Alternatives C4A, 

C4B, and C4C would represent substantial potential construction-related effects on non-developed 

land when compared with the No Build Alternative. The northern extent of Alternatives C4A and 

C4C, near Dallas and Fort Worth, would follow the TRE tracks between Fort Worth and Dallas, then

continue south on the BNSF alignment. The northern extent of Alternative C4B would follow a new 

elevated high-speed alignment in the IH-30 median between Fort Worth and Dallas. However, the 

majority of the three alternatives follow alignments outside existing transportation corridors starting 

in Waxahachie for Alternatives C4A and C4C and in Arlington for Alternative C4B. Construction of 

the portions of the alternatives outside existing transportation corridors would have a noticeable, 

inevitable effect on non-developed land within the EIS Study Area. The potential operations effects 

associated with Alternative C4A Higher-Speed Rail with regard to developed land covers within the 

EIS Study Area would be considered moderate because of disruption of wildlife species from noise 

and vibration from the additional rail traffic along the route.

Wildlife Corridors and Assemblages and Sensitive Plant Communities 

The potential effects associated with construction of Alternatives C4A, C4B, and C4C with regard to 

animal assemblages and terrestrial communities would be considered substantial when compared 

with the No Build Alternative, as construction of the portions of the alternatives outside existing 

transportation corridors would have a noticeable, inevitable effect on these resources within the 
TBG101414223433SCO

5.0 Effects on Natural Ecological Systems and Wildlife

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 5-4

EIS Study Area. High-speed rail options would likely be fully fenced, lessening the likelihood of 

strikes when compared with the higher-speed rail options. However, high-speed rail options would 

have a higher potential for operations effects overall on wildlife corridors and assemblages within 

the EIS Study Area than the higher-speed rail options as the noise and vibration generated by highspeed rail would travel farther than the noise generated by higher-speed rail. Overall, the potential 

operations effects on wildlife corridors and assemblages and sensitive plant communities would be 

moderate. 

REAP Composite Scores 

The percentages of the total land coverage of the EIS Study Area composed of higher ecological 

importance/value land coverage areas for the Central Section alternatives would represent a 

substantial construction-related effect when compared with the No Build Alternative. Construction 

of the portions of the Central Section alternatives outside existing transportation corridors would 

have a noticeable, inevitable effect on lands with higher ecological importance within the EIS Study 

Area. The operations effects would be moderate. 

Potential Construction Effects 

Short- and long-term effects on terrestrial biological resources and habitats would be anticipated as 

a result of constructing Alternatives C4A, C4B, and C4C and could include the clearing of vegetation 

for construction equipment and the stockpiling of soil, ballast, or other construction materials. 

Additionally, short-term noise, vibration, and air pollution from construction equipment and 

activities could affect terrestrial habitats and their wildlife. For Alternatives C4A and C4C, such 

effects would be considered substantial when compared with the No Build Alternative. Although 

Alternatives C4A and C4C would begin at the Fort Worth and follow the TRE tracks to Dallas, then 

continue on the BNSF alignment south toward Waxahachie (with Alternative C4C including a link 

from Hillsboro directly to Fort Worth parallel to the UPRR alignment), the alternatives would enter a 

new high-speed corridor outside of existing transportation corridors to travel south to Hillsboro and 

Taylor. For Alternative C4B, such effects would also be considered substantial when compared with

the No Build Alternative. Alternative C4B would begin at both Fort Worth and Dallas, with trains 

following a new elevated high-speed alignment in the IH-30 median to Arlington. However, 

Alternative C4B would merge and turn south toward Hillsboro on a new high-speed alignment and 

then follow the same high-speed alignment as Alternative C4A from Hillsboro to Taylor and south to 

San Antonio. 

Potential Operations Effects 

Alternatives C4A, C4B, and C4C are higher- and high-speed rail alternatives, with much of their 

routes constructed within new alignments outside of existing transportation corridors. Potential 

operations effects from wildlife strikes would be considered moderate when compared with the No 

Build Alternative as these higher- or high-speed rail alternatives would likely be fully fenced. 

However, construction of fenced rail lines would result in significant effects on wildlife migration by 
TBG101414223433SCO

5.0 Effects on Natural Ecological Systems and Wildlife

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 5-5

preventing or impeding movement across the railroad line. To mitigate such effects, the portions of 

the routes outside of existing transportation corridors could be designed with alternative pathways 

or underpasses to maintain wildlife migratory paths, reducing potential effects. Overall, the 

potential operations effects would be moderate. 

5.4 Southern Section: San Antonio to South Texas 

This section provides potential effects and their relative intensity from the construction and 

operation of the build alternatives in the Southern Section on natural ecological systems and 

wildlife. With the exception of operations-related impacts to wildlife corridors/assemblages and 

sensitive plant communities, the intensity of effects for the higher- and high-speed rail alternatives 

would be the same as described below and in Table 5-1. 

National Land Cover Database – Land Cover Types 

Alternative S4 would begin at the San Antonio VIA Transit Center station and continue southeast 

along the UPRR alignment to George West, where the alternative would enter a right-of-way outside 

of existing transportation corridors, to Alice. At Alice, there would be a stop where this alternative 

would divide into three legs. The first leg would travel west along the KCS Railway to San Diego, 

Texas, where it would enter a right-of-way outside of existing transportation corridors that would 

extend to Pescadito, just east of Laredo, and then rejoin the KCS Railway to end at the Laredo 

International Airport. The second leg would travel south along rebuilt abandoned track to McAllen, 

where a connection could be made to Harlingen and Brownsville over a proposed commuter rail 

service. The third leg would travel east along the KCS Railway to Corpus Christi to a new station 

facility at Corpus Christi International Airport. 

Alternative S6 would begin at the San Antonio VIA Transit Center station and continue on a direct 

new corridor outside of existing transportation corridors to a station near the Laredo-Columbia 

Solidarity Bridge. 

The construction of Alternative S4 would affect non-developed land during construction of the 

portions of the route outside of existing transportation corridors. However, significant portions of 

Alternative S4 would be constructed within existing routes (e.g., KCS Railway and revitalization of 

abandoned tracks), minimizing potential effects on resources to a moderate level. The potential 

operations effects associated with Alternative S4 with regard to developed land covers within the 

EIS Study Area would be considered moderate as significant portions of the alternative would 

operate within existing rights-of-way.

The construction of Alternative S6 would have a substantial effect on non-developed land when 

compared with the No Build Alternative as this alternative would follow a new direct corridor outside 

of existing transportation corridors from San Antonio to a station near the Laredo-Columbia 

Solidarity Bridge. Construction of this alternative would have a noticeable, inevitable effect on nondeveloped land within the EIS Study Area. The potential operations effects associated with 
TBG101414223433SCO

5.0 Effects on Natural Ecological Systems and Wildlife

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 5-6

Alternative S6 on developed land covers within the EIS Study Area would be moderate because of 

disruption of wildlife species from noise and vibration from the rail traffic along the route. However, 

the route outside existing transportation corridors could be designed with alternative pathways or 

undercrossings to maintain wildlife migratory paths or corridors. In addition, the majority of effects 

on non-developed land covers would be during construction of the alternative.

Wildlife Corridors and Assemblages and Sensitive Plant Communities 

The potential effects associated with construction of Alternative S4 with regard to wildlife corridors 

and assemblages or sensitive plant communities would be considered negligible when compared 

with the No Build Alternative, as this portion of Alternative S4 would be constructed within existing 

rights-of-way and would not likely create new effects on sensitive communities. 

No wildlife corridors and assemblages or sensitive plant communities were identified within the EIS 

Study Area for Alternative S6. Under Alternative S6, potential construction and operations effects

on wildlife corridors and assemblages and sensitive plant communities would be similar to the No 

Build Alternative. 

REAP Composite Scores 

The portions of Alternative S4 that cross Brooks and Live Oak Counties would be constructed on 

existing rights-of-way and would have a negligible effect on lands with higher ecological importance 

within the EIS Study Area. However, construction of the portions of Alternative S4 outside of existing 

transportation corridors, especially near Duval and Webb counties, would represent a substantial 

effect. Overall, the construction and operation of Alternative S4 would have a substantial effect 

(noticeable, inevitable effect) on lands with higher ecological importance within the EIS Study Area. 

The majority of lands with higher ecological importance for Alternative S6 are near Dimmet and 

Webb counties. Alternative S6 would have a substantial effect on lands with higher ecological 

importance when compared with the No Build Alternative as construction and operation of this new 

alignment outside of existing transportation corridors would have a noticeable, inevitable effect on 

resources.

Potential Construction Effects 

Short- and long-term effects on terrestrial biological resources and habitats would be anticipated as 

a result of constructing Alternatives S4 and S6 and could include the clearing of vegetation for 

construction equipment and the stockpiling of soil, ballast, or other construction materials.

Additionally, short-term noise, vibration, and air pollution from construction equipment and 

activities could temporarily affect terrestrial habitats and their wildlife. For Alternative S4, such 

effects would be considered moderate when compared with the No Build alternative as a portion of 

this alternative would be constructed on existing rail rights-of-way. For Alternative S6, such effects

would be considered substantial when compared with the No Build Alternative as this alternative 

would begin at the San Antonio VIA Transit Center station and continue on a new, direct high-speed 
TBG101414223433SCO

5.0 Effects on Natural Ecological Systems and Wildlife

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 5-7

corridor outside of existing transportation corridors to a station near the Laredo-Columbia Solidarity 

Bridge. Construction of the new route outside of existing transportation corridors would have a 

noticeable, inevitable effect on resources within the EIS Study Area.

Potential Operations Effects 

Alternative S4 is a higher-speed rail alternative, and Alternative S6 is a higher- and high-speed rail

alternative. Potential operations effects from wildlife strikes would be considered negligible when 

compared with the No Build Alternative as these higher- or high-speed rail alternatives would likely 

be fully fenced. However, construction of fenced rail lines would result in significant effects on

wildlife migration by preventing or impeding movement across the railroad line. To mitigate such 

effects, the portions of the routes outside of existing transportation corridors could be designed 

with alternative pathways to maintain wildlife migratory paths, reducing potential effects.

5.5 Summary of Potential Effects 

Table 5-1 summaries the qualitative assessment of potential effects (negligible, moderate, or 

substantial) for the alternatives. As stated previously, it is important to note that the acreages listed 

below are not the actual areas of effect associated with construction and operation of any of the 

alternatives. This service-level analysis uses the 500-foot EIS Study Area to determine the types of 

resources that may be affected and, more importantly, the relative magnitude of resources that 

may be affected. As stated previously, alignment routes could be built alone, or combined with 

other section routes. More than one alternative in the Central or Southern sections could also be 

built in the future as the alternatives provide different service options for the independent 

destinations. Details about how alternatives might connect would be analyzed at the project-level 

EIS phase.

5.6 Subsequent Analysis and Avoidance, Minimization, and Mitigation 

Strategies 

Once a preferred alternative is selected, field investigations or surveys will be conducted to 

determine the likelihood of effects on sensitive habitats within the EIS Study Area and to determine 

the extent and type of general and sensitive natural ecological systems and wildlife, including 

formal biological assessments for protected species and consultation with USFWS, TPWD, and 

ODWC, as needed. The boundaries of sensitive wildlife corridors, sensitive plant communities, or 

areas identified as having a higher ecological importance/value land coverage will be confirmed to 

avoid or minimize effects on these areas. Habitat and species assessments will be conducted in 

accordance with federal and state regulations. 

Avoidance and minimization of project-level effects would be incorporated when feasible. If effects 

cannot be avoided or minimized, mitigation strategies would be implemented. Mitigation measures 

to reduce or eliminate effects on sensitive habitats and species would be coordinated with federal 

and state agencies. To minimize construction effects and minimize disturbance of terrestrial and 
TBG101414223433SCO

5.0 Effects on Natural Ecological Systems and Wildlife

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 5-8

aquatic habitats and wildlife, BMPs would be used during construction and operations. BMPs may 

include the following: 

 Construct multiple and varying crossing structures at a wildlife crossing point to provide 

connectivity for species likely to use a given area.

 Determine and construct the appropriate number, spacing, and location of crossing structures 

based on species-specific information. 

 Monitor structures for obstructions, such as detritus or silt blockages, that impede movement.

 Manage human activity near crossing structures, with use of measures such as fencing and 

signage. 

 Routes outside existing transportation corridors could be designed with alternative pathways or 

undercrossings to maintain wildlife migratory paths or corridors. 

Local ordinances would be followed for erosion, sediment, and stormwater controls during 

construction to minimize potential effects on aquatic resources. For terrestrial habitats that might 

be temporarily disturbed by construction, preconstruction conditions or better would be restored 

once construction is complete.
TBG101414223433SCO

5.0 Effects on Natural Ecological Systems and Wildlife

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 5-9

Table 5-1: Summary of Acreages and Effects

Resource No Builda 

Northern Section Central Section Southern Section 

N4A 

(CONV) 

C4A 

(HrSR and HSR) 

C4B 

(HrSR and HSR) 

C4C 

(HrSR and HSR) 

S4 

(HrSR) 

S6 

(HrSR and HSR) 

Land Cover Type 

Acres of 

Land 

Cover 

Total Area of 

EIS Study 

Area 

Acres of Land 

Cover 

Total Area of 

EIS Study 

Area 

Acres of Land 

Cover 

Total Area of 

EIS Study Area 

Acres of 

Land Cover 

Total Area of 

EIS Study 

Area 

Acres of 

Land Cover 

Total Area of EIS 

Study Area 

Acres of 

Land Cover 

Total Area of 

EIS Study Area 

Developed, High Intensity N/A 1,249

46%

1,347

38%

1,318

36%

1,533

38%

776

32%

84

8% Developed, Low Intensity N/A 2,046 1,667 1,374 2,108 2,888 202

Developed, Medium Intensity N/A 1,625 1,809 1,810 2,080 2,019 97

Developed, Open Space N/A 2,027 2,741 2,140 3,401 2,315 318

Barren Land (Rock/Sand/Clay) N/A 53 <1% 48 <1% 30 <1% 60 >1% 260 1% 108 1%

Cultivated Crops N/A 960 6% 3,013 15% 3,252 17% 3,350 14% 2,174 9% 1,177 14%

Deciduous Forest N/A 1,748 12% 1,284 6% 812 4% 1738 7% 340 1% 112 1%

Emergent Herbaceous Wetlands N/A 8 <1% 18 <1% 10 <1% 18 <1% 64 <1% 9 <1%

Evergreen Forest N/A 15 <1%% 261 1% 237 1% 264 1% 41 <1% 58 1%

Grassland/Herbaceous N/A 4,465 30% 4,274 21% 3,886 21% 5,415 23% 2,330 9% 1,729 20%

Mixed Forest N/A 0 0 63 <1% 63 <1% 63 <1% 24 0% 52 1%

Open Water N/A 120 1% 80 <1% 59 <1% 84 <1% 45 <1% 11 <1%

Pasture/Hay N/A 783 5% 1,404 7% 1,602 9% 1,453 6% 2,948 12% 578 7%

Shrub/Scrub N/A 2 <1% 1,720 9% 1,716 9% 1,728 7% 8,574 34% 3,852 44%

Woody Wetlands N/A 7 <1% 400 2% 366 2% 418 2% 396 2% 279 3%

Qualitative Analysis - Negligible Substantial Substantial Substantial Moderate Substantial 

Wildlife Corridors and Assemblages and Sensitive Plant Communities (potential acres in EIS Study Area/Qualitative Analysis) 

Wildlife Corridors and Assemblages/Rookeries 0 85

Negligible 

107

Substantial 

66

Substantial 

107

Substantial 

0

Negligible 

0

Negligible 

Sensitive Plant Communities 0 0

Negligible 

628

Substantial 

628

Substantial 

628

Substantial 

678

Negligible 

0

Negligible 

REAP Composite Scores/Ecological Importance Rank 

Acres within 

EIS Study 

Area 

Total Area of 

EIS Study 

Area 

Acres within 

EIS Study 

Area 

Total Area of 

EIS Study 

Area 

Acres within 

EIS Study Area 

Total Area of 

EIS Study Area 

Acres 

within EIS 

Study Area 

Total Area of 

EIS Study 

Area 

Acres within 

EIS Study 

Area 

Total Area of 

EIS Study Area 

Acres within 

EIS Study 

Area 

Total Area of 

EIS Study Area 

1 N/A 100

10% 

32

18% 

32

18% 

32

15% 

21

15%

31

10 N/A 665 1,884 1,839 1,884 1,088 538 21% 

25 N/A 770 1,621 1,457 1,640 2,550 1,227

50 N/A 1,829

90%

3,407

82%

2,727

82%

3,613

85%

4,589

85%

2,389

79%

100 N/A 11,744 13,184 12,621 16,546 16,943 4,469

Total (acres) N/A 15,107 - 20,128 - 18,675 - 23,714 - 25,193 - 8,653 -

Qualitative Analysis - Negligible Substantial Substantial Substantial Substantial Substantial 

a The No Build Alternative, as identified, includes existing and potential expansion of roadway, passenger rail, and air travel facilities within the EIS Study Area; however, for the service-level evaluation, identifying levels of effect from potential expansion of those 

facilities is speculative and would be dependent on project-specific analysis

TBG101414223433SCO

ReferencesAbbreviations and AcronymsReferences

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 6-1

6.0 References 

Multi-Resolution Land Characteristics Consortium (MRLC). 2011. National Land Cover Database.

2011 (NLCD2011) Product Legend. Available at http://www.mrlc.gov/nlcd11_leg.php. 

Accessed May 27, 2014.

Texas Climate Data. 2014. Available at http://web2.airmail.net/danb1/climate.htm. Accessed April 

23, 2014.

Texas Department of Transportation (TxDOT). 2004. Environmental Manual. October 2004.

Texas Department of Transportation (TxDOT). 2014. Texas-Oklahoma Passenger Rail Study Route 

Alternatives Analysis. June.

Texas Parks and Wildlife Department (TPWD). 2014. Vegetation. Available at 

http://www.tpwd.texas.gov/landwater/land/habitats/cross_timbers/vegetation/. Accessed 

August 12, 2014.

U.S. Climate Data. 2014. Temperature - Precipitation - Sunshine – Snowfall. Available at 

http://usclimatedata.com/. Accessed April 23, 2014.

U.S. Environmental Protection Agency (EPA). 2011. Regional Ecological Assessment Protocol 

(REAP): Project Report. Region 6. June 2011.

U.S. Environmental Protection Agency (EPA). 2014. Level III and IV Ecoregions of the Continental 

United States. Available at http://www.epa.gov/wed/pages/ecoregions/level_iii_iv.htm. 

Accessed May 30, 2014.

University of Oklahoma. 2014. Oklahoma Climatology Survey: Climate of Oklahoma. Available at 

http://climate.ok.gov/index.php/site/page/climate_of_oklahoma. Accessed April 23, 2014.

TBG101414223433SCO

PreparersAbbreviations and AcronymsPreparers

Texas-Oklahoma Passenger Rail Study July 2016

Natural Ecological Systems and Wildlife Technical Study Page 7-1

7.0 Preparers 

Melissa Fowler/Biologist/CH2M 

M.S., 2010, Environmental Studies, Emphasis: Environmental Science, California State 

University, Fullerton

B.S., 2005, Biological Science, California State University, Fullerton

A.A., 2001, Liberal Studies, Fullerton College, Fullerton

Years of Experience: 11

Christopher Powers/Project Manager/Senior Biologist/CH2M 

B.S., 1999, Biology, Union College, Schenectady, New York

M.A., 2001, Science Education, Union College, Schenectady, New York

Years of Experience: 13

Robert Price/Senior Environmental Scientist/CH2M 

B.S., 1992, Zoology, History, Miami University, Ohio

M.S., 1994, Environmental Science, Indiana University, Indiana

Master of Public Affairs, 1994, Aquatic Ecosystems Management, Indiana University

Years of Experience: 18
PreparersAbbreviations and AcronymsPreparers

This report was written on behalf of the Texas Department of Transportation by 

www.ch2m.com