J.04_C.2_Rio_Grande_Draft_PEIS_July_31 _2007.pdf

Draft Programmatic Environmental Impact Statement Improvements to the USIBWC Rio Grande Flood Control Projects along the Texas-Mexico Border

July 2007 Technical Support:

PARSONS

Austin, Texas

Lead Agency:

United States Section International Boundary and Water Commission

El Paso, Texas

Cooperating Agencies:

U.S. Army Corps of Engineers Galveston District, Texas

U.S. Bureau of Reclamation El Paso Field Division, Texas

U.S. Fish and Wildlife Service Corpus Christi, Texas

Ecological Services Field Office

Cover Sheet

PROGRAMMATIC ENVIRONMENTAL IMPACT STATEMENT

IMPROVEMENTS TO THE USIBWC RIO GRANDE FLOOD CONTROL PROJECTS

ALONG THE TEXAS-MEXICO BORDER

(X) Draft ( ) Final

Lead Agency

United States Section, International Boundary and Water Commission

(USIBWC)

El Paso, Texas

Cooperating Agencies

United States Bureau of Reclamation United States Fish and Wildlife Service U.S. Army Corps of Engineers

Abstract

The USIBWC anticipates the need to improve capabilities or functionality of three Rio Grande flood control projects (FCP) located in the Texas-Mexico border:

Rectification FCP, Presidio FCP, and Lower Rio Grande FCP.

Improvement measures associated with the project core mission of flood protection, boundary stabilization, and water delivery are evaluated under the Enhanced Operation and Maintenance (EOM) Alternative. Additional measures intended to improve water use, quality, and conservation are considered under the Integrated Water Resources Management (IWR) Alternative; and measures in support of local or regional initiatives for increased utilization of the project or to improve environmental conditions are evaluated under the Multipurpose Project Management (MPM) Alternative.

This Programmatic Environmental Impact Statement (PEIS) evaluates potential environmental consequences of alternatives under consideration for improvement of the three flood control projects. The USIBWC will apply the programmatic evaluation as an overall guidance for the anticipated implementation of future environmental evaluations of individual improvement projects, implementation of which could be possible within a 20-year timeframe.

Other Requirements Served

This PEIS is intended to serve other environmental review and consultation requirements pursuant to 40 CFR 1502.25(a).

Comments Submittal

The Draft PEIS will be available for a 45-day public review period. Comments should be directed by September 24, 2007 to:

Mr. Daniel Borunda Environmental Management Division

USIBWC

4171 North Mesa St., C-100 El Paso, Texas 79902

Date of Draft availability to USEPA and the Public:

August 10, 2007.

DRAFT 1

PROGRAMMATIC ENVIRONMENTAL IMPACT STATEMENT 2

IMPROVEMENTS TO USIBWC RIO GRANDE FLOOD 4

CONTROL PROJECTS ALONG THE TEXAS-MEXICO 5

BORDER 6

PREAMBLE 8

This is a Programmatic Environmental Impact Statement (PEIS) for future improvement 9 alternatives of three flood control projects operated and maintained by the United States 10 Section, International Boundary and Water Commission (USIBWC) along the Texas-Mexico 11 border: the Rio Grande Rectification Project, the Presidio-Ojinaga Flood Control Project, and 12 the Lower Rio Grande Flood Control Project. 13

The PEIS is organized in four chapters, a Program Background and Alternatives Chapter, 14 and individual chapters for each flood control project. 15

Chapter I, Program Background and Alternatives, presents background information on the 16 PEIS objective and scope of the environmental review; describes the alternatives and the basis 17 for their development; and documents the environmental compliance and coordination process. 18 Chapter I is composed of three sections, as follows: 19

Section 1, Purpose of and Need for Action, indicates the PEIS objective, scope of the 20 environmental review, and a brief description of the flood control projects. 21

Section 2, Alternatives Formulation, describes the development of the alternatives 22 based on opportunities and constraints, identifies potential project improvement 23 measures, and defines alternatives based on project objectives. 24

Section 3, Environmental Compliance and Coordination, documents the consultation 25 process followed to develop the alternatives and evaluate potential environmental 26 consequences. 27

Chapters II, III and IV provide an assessment of environmental consequences of 28 implementing anticipated or possible measures for improvement of each of the flood control 29 projects. Each chapter contains the following three sections: 30

Section 1, Description of Alternatives, identifies measures associated with four 31 alternatives for improvement of the flood control projects selected or the PEIS 32 evaluation: a No Action Alternative, the continued implementation of current operation 33 and maintenance (O&M) practices, and three action alternatives: Enhanced Operation 34 and Maintenance (EOM) Alternative, Integrated Water Resources Management (IWR) 1 Alternative; and Multipurpose Project Management (MPM) Alternative. 2

Section 2, Affected Environment, provides the basis for evaluation of potential impacts 3 in the areas of water, biological, land use, cultural and socioeconomic resources, as 4 well as environmental health issues (air quality, noise and environmental hazards). 5

Section 3, Environmental Consequences, is an analysis of potential effects associated 6 with implementation of each alternative. This analysis is presented by resource area, 7 following the sequence used in describing the affected environment. 8

Support documentation is provided in Appendices, as follows: 9

A. References 10

B. County Listings of Threatened and Endangered Species 11

Draft Programmatic Environmental Impact Statement Executive Summary

ES-1 USIBWC

EXECUTIVE SUMMARY

Purpose of and Need for Action

The USIBWC is proposing a range of alternatives for maintenance activities and future improvements to three of its flood control projects located along the Rio Grande in Texas.

Those flood control projects, the locations of which are identified in Figure ES-1, are:

• Rio Grande Rectification Project (Rectification FCP) extending 84.4 river miles along the Rio Grande, downstream from American Diversion Dam to Fort Quitman, Texas.

• Presidio-Ojinaga Flood Control Project (Presidio FCP) extending over 13.1 river miles of the Rio Grande near Presidio, Texas.

• Lower Rio Grande Flood Control Project (Lower Rio Grande FCP) extending 186 river miles on the Rio Grande, from Peñitas, Texas to the Gulf of Mexico, and including 120 miles of interior floodway.

The Programmatic Environmental Impact Statement (PEIS) is being prepared to evaluate maintenance improvement alternatives that would allow USIBWC to minimize potential environmental impacts and take advantage of environmental and recreational opportunities while meeting its mandate for flood protection, boundary stabilization, and water delivery.

Over a 20-year planning period, the USIBWC anticipates the need to improve capabilities or functionality of the flood control projects. While some improvements to the flood control projects are already in a planning stage or have been developed at a conceptual level, others represent measures considered feasible but not currently envisioned for implementation.

Known or anticipated improvements are typically associated with the core mission of flood control, boundary stabilization, and water delivery. Other improvements are associated with additional goals adopted by the USIBWC in support of the projects’ core mission. Those goals include improvements in water use, quality, or conservation, and multipurpose utilization of the projects in support of local or regional initiatives for recreational use or environmental improvement.

The USIBWC will apply the programmatic evaluation of potential impacts as an overall guidance for future environmental evaluations of individual improvement projects whose implementation is anticipated or possible within a 20-year timeframe. Once any given improvement project is identified for future implementation, site-specific environmental documentation will be developed based on project specifications and PEIS findings.

Alternatives Considered in Detail

A summary of potential measures under consideration is presented in Table ES-1. For the PEIS evaluation, measures identified as feasible were organized into three action alternatives that reflect the following project goals:

Lower Rio Grande Flood Control Project

Presidio-Ojinaga Flood Control Project

Rio Grande Rectification Project

Tijuana River Flood Control Project

G ulf of California

Paci fic O cean

Gulf of Mexico

El Paso

Texas

Arizona New Mexico

Oklahoma

California

KansasColorado Utah

Arkansas

Nevada Missouri

Louisiana

Sonora

Chihuahua

Durango

Coahuila De Zaragoza

Sinaloa Nuevo Leon

Baja California Sur

Tamaulipas

Zacatecas

Baja California Norte

Rio Grande

Nazas

Conchos

Rio SaladoYa qu i

Ri o

So no ra

Rio Fuerte

Ba vi sp e

Papigochic

M oc te zu m a

Ya qu i

San Lorenzo

RedBrazos

Ri o

G ra nd e

Gila

Pe co s

Arkansas

Canadian

Salt

Colorado

La Paz

Culiacan

Saltillo

Chihuahua

Monterrey

Hermosillo

Tulsa

Austin

Tucson Dallas

Houston

El Paso

Phoenix

Wichita

San Diego

Las Vegas

Fort Worth

San Antonio

Los Angeles

Albuquerque Oklahoma City

Corpus Christi

115°0'0"W

115°0'0"W

110°0'0"W

110°0'0"W

105°0'0"W

105°0'0"W

100°0'0"W

100°0'0"W 95°0'0"W

95°0'0"W

25°0'0"N

25°0'0"N

30°0'0"N

30°0'0"N

35°0'0"N

35°0'0"N

Fig. ES-1 Location of USIBWC Projects

Programmatic EIS International Boundary and Water Commission, United States Section¹ 0 100 200 300 400 50050 Miles

0 200 400 600 800100 Kilometers

Scale = 1: 6,200,000

ES-3 USIBWC

Table ES-1 Potential Changes Relative to Current O&M Practices

FLOOD CONTROL PROJECT

Rectification Presidio LRGFCP

FLOOD CONTROL SYSTEM ALONG THE RIO GRANDE

Levee Improvements Levee height increase X X X Structural levee improvements X X X Partial relocation within ROW or new flood easements X

Changes in Floodway Management Streambank stabilization with vegetation combined with mechanical means Changes in vegetation removal and timing/extent of mowing X Agricultural/grazing use Restricted Use Zones X

Changes in Channel Maintenance Sediment removal and disposal X X X Debris removal Shore/aquatic vegetation removal X New/changes to diversion structures

INTEGRATED WATER RESOURCES MANAGEMENT

Water Use and Conservation Salt cedar management X X Revegetation with low-water use species Irrigation BMPs to increase water delivery efficiency X Wetlands improvement Support maintenance of irrigation structures and drains X

Water Quality Water quality monitoring Modified irrigation drain maintenance X X Limited floodway revegetation to reduce erosion and sediment load

MULTIPURPOSE PROJECT MANAGEMENT

Jurisdictional Floodway Use Non-USIBWC floodway maintenance Parks, nature trails, recreational areas X X Control of invasive/exotic species X X Wildlife habitat conservation Establish/improve riparian corridors

Cooperative Agreements and Regional Initiatives Vegetation removal and timing/extent of mowing X Control of invasive/exotic species outside ROW X X Wildlife habitat conservation inside or outside ROW X X X Increase backwaters at mouth of arroyos to increase aquatic habitat Reconnection of historic, low-elevation meanders for aquatic habitat Levee setbacks at flood prone areas for increased habitat Flow regime modification to provide year-round baseflow X Watershed management for sediment control Upstream sediment control (dams, traps) X X

ES-4 USIBWC

1. Measures associated with projects’ mission of flood control, boundary stabilization and water delivery, evaluated under the Enhanced Operation and Maintenance (EOM) Alternative;

2. Measures intended to improve water use, quality, and conservation, considered under the Integrated Water Resources Management (IWR) Alternative; and

3. Measures in support of local or regional initiatives for increased utilization of the project or to improve environmental conditions, evaluated under the Multipurpose Project Management (MPM) Alternative.

Summary of Environmental Consequences

The PEIS compares potential environmental consequences of the EOM, IWR, and MPM alternatives with those expected from continued use of current management and operational practices evaluated under the No Action Alternative. Impacts were evaluated for the following resource areas: water, biological resources, cultural and socioeconomic resources; land use;

and environmental health. A summary comparison of potential environmental consequences of the alternatives by resource area, with general application to the three flood control projects under evaluation, is presented in Table ES-2.

USIBWC ES- 5

Table ES-2 Summary of Environmental Consequences of Alternatives for Improvement of the Rectification FCP

No Action Alternative Enhanced Operation and

Management (EOM) Alternative

Integrated Water Resources Management

(IWR) Alternative

Multipurpose Project Management

(MPM) Alternative

Water Resources Current containment may be insufficient to fully control severe floods.

Levee system would increase flood containment capacity to control severe floods.

Flood containment capacity would improve, as well as water resource utilization.

Flood containment capacity would improve; a moderate increase in water use by floodway vegetation would be offset by improved use of water resource.

Biological Resources

The on-going mowing of the levee slopes and floodway would maintain this habitat as relatively low quality for wildlife use.

There would be no changes relative to current conditions in terms of potential impacts to wildlife habitat, aquatic ecosystems, wetlands, or unique or sensitive areas.

Little or no changes are expected from the EOM Alternative in terms of vegetation, wildlife habitat, aquatic ecosystems, wetlands, or unique or sensitive areas. Non-native grasses removed by levee improvements would re-establish after construction.

The relatively low-quality floodway habitats would be maintained.

Potential effects on wetlands would be minimized.

Salt cedar management and revegetation would increase habitat for native plant species and wildlife, including threatened and endangered species.

Impacts to wetlands, aquatic ecosystems, and other biological resources would be similar to those of the No Action and EOM Alternatives.

Regional habitat revegetation and conservation initiatives outside the levee corridor would provide additional habitat for native plant species and wildlife, including threatened and endangered species;

Improved sediment management and habitat development would improve aquatic ecosystems.

Land Use

Existing residential communities, agricultural lands, and recreational uses would be maintained.

Effects, as in the No Action Alternative. Floodway management changes, including increased U.S. Border Patrol operations, would limit some recreational uses.

Similar to those of the No Action and EOM Alternatives.

Beneficial effects would be expected from multi-jurisdictional, cooperative agreements to promote recreational opportunities, including trail systems.

Cultural Resources No additional impacts on historical and archaeological resources.

Historical structures and/or archaeological resources could be affected by changes to the levee system configuration.

Similar to those of the EOM Alternative. Impacts would depend on the extent of the proposed projects.

Similar to those of the EOM Alternative.

USIBWC ES- 6

No Action Alternative Enhanced Operation and

Management (EOM) Alternative

Integrated Water Resources Management

(IWR) Alternative

Multipurpose Project Management

(MPM) Alternative

Socioeconomic Resources

No change relative to current operations on impacts to regional economics, environmental justice, and transportation.

Temporary input of project funds would not significantly improve regional economics. Adverse effects to minority and low-income populations are not expected.

Increased use of main roadways and access roads would be minor and limited to project duration.

Impacts would be the same as the EOM Alternative. Roadway utilization would depend on the extent of proposed initiatives.

Impacts would be the same as the EOM Alternative.

Environmental Health

Environmental Health

Emissions generating activities and noise generation would be the same as the current ongoing activities. There would be no impacts to public health and environmental hazards.

Regional air quality would not be impacted. Small increases in emissions and noise generation would be temporary during construction activities. There would be no impacts to public health and environmental hazards.

Impacts would be the same as the EOM Alternative. Roadway utilization would depend on the extent of proposed initiatives.

Impacts would be the same as the EOM Alternative.

DRAFT PROGRAMMATIC ENVIRONMENTAL IMPACT STATEMENT 1

IMPROVEMENTS TO USIBWC RIO GRANDE FLOOD CONTROL 3

PROJECTS ALONG THE TEXAS-MEXICO BORDER 4

CHAPTER I 5

PROGRAM BACKGROUND AND ALTERNATIVES 7

Draft Programmatic Environmental Impact Statement Chapter I – Program Background and Alternatives

8/1/2007 i USIBWC

TABLE OF CONTENTS 1

ACRONYMS AND ABBREVIATIONS....................................................................................................iii 2 SECTION 1 PURPOSE OF AND NEED FOR ACTION ...................................................................... 1-1 3

1.1 Background....................................................................................................................... 1-1 4

1.1.1 Scope of the Environmental Review ....................................................................... 1-1 5

1.1.2 USIBWC Authority................................................................................................... 1-2 6

1.2 Purpose of and Need for Action........................................................................................ 1-2 7

1.3.1 Rio Grande Rectification Flood Control Project ...................................................... 1-4 8

1.3.2 Presidio-Ojinaga Flood Control Project................................................................... 1-4 9

1.3.3 Lower Rio Grande Flood Control Project ................................................................ 1-5 10

SECTION 2 FORMULATION OF ALTERNATIVES ............................................................................ 2-1 11

2.1 Initial Identification of Potential Measures ........................................................................ 2-1 12

2.2 Basis for Alternatives Formulation .................................................................................... 2-3 13

2.2.1 Flood Control........................................................................................................... 2-3 14

2.2.2 Water Delivery and Boundary Preservation............................................................ 2-4 15

2.2.3 Project Scale and Diversity ..................................................................................... 2-4 16

2.2.4 Environmental Initiatives and Cooperative Agreements ......................................... 2-5 17

2.2.5 Mitigation and Compensation Measures................................................................. 2-6 18

2.3 Definition of Alternatives by Project Objective .................................................................. 2-6 19 SECTION 3 ENVIRONMENTAL COMPLIANCE AND COORDINATION .......................................... 3-1 20

3.1 Public and Agency Consultation ....................................................................................... 3-1 21

3.1.1 Scoping Meetings.................................................................................................... 3-1 22

3.1.2 Notifications to Agencies, Elected Officials, Organizations, and Individuals .......... 3-2 23

3.2 PEIS Preparation and Review .......................................................................................... 3-2 24

3.2.1 Cooperating Agencies............................................................................................. 3-2 25

3.2.2 PEIS Preparation .................................................................................................... 3-3 26

LIST OF TABLES 27

Table I-2.1 Potential Changes Relative to Current O&M Practices ................................................... 2-2 28 Table I-2.2 Opportunities and Constraints for Project Improvement ................................................. 2-3 29 Table I-2.3 Measure Organization by Categories used in the Formulation of Alternatives ............... 2-7 30 Table I-3.1 Technical Personnel Responsible for PEIS Preparation ................................................. 3-3 31 Table I-3.2 PEIS Reviewers............................................................................................................... 3-4 32

8/1/2007 ii USIBWC

LIST OF FIGURES 1

Figure 1 Location of Flood Control Projects .................................................................................. 1-6 2 Figure 2 Upper Reach of the Rectification Flood Control Project.................................................. 1-7 3 Figure 3 Lower Reach of the Rectification Flood Control Project.................................................. 1-8 4 Figure 4 Presidio-Ojinaga Flood Control Project Location ............................................................ 1-9 5 Figure 5 Presidio-Ojinaga Flood Control Project – Aerial Photography ...................................... 1-10 6 Figure 6 Lower Rio Grande Flood Control Project Location........................................................ 1-11 7 Figure 7 Lower Rio Grande Flood Control Project, Upper River Reach and Main Floodway ..... 1-12 8 Figure 8 Lower Rio Grande Flood Control Project, Lower River Reach...................................... 1-13 9 Figure 9 Lower Rio Grande Flood Control Project, North and Arroyo Colorado Floodways....... 1-14 10

8/1/2007 iii USIBWC

ACRONYMS AND ABBREVIATIONS 1

Ac-ft acre feet ac-ft/yr acre feet per year

ANSI American National Standards Institute

AQCR Air Quality Control Region

ARPA Archaeological Resource Protection Act

CEQ Council on Environmental Quality cfs cubic feet per second

DNL day-night average sound level

E.O. executive order

EOM enhanced operation and maintenance

FCP Flood Control Project

FM farm-to-market

HCCRD Hudspeth County Conservation and Reclamation District

HPA high probability area

IH Interstate

INS Immigration and Naturalization Service

IWR Integrated water resources management

JTF-6 Joint Task Force - Six

LRGV Lower Rio Grande Valley

Mg/L milligrams per liter mgd million gallons per day

MOU memorandum of understanding

MPM Multi-purpose project management

MSL mean sea level

MxIBWC Mexico Section International Boundary and Water Commission

NAAQS National Ambient Air Quality Standards

NEPA National Environmental Policy Act

NHPA National Historic Preservation Act

NOI Notice of Intent

NRCS National Resources Conservation Service

NRHP National Register of Historic Places

NWR National Wildlife Refuge

O&M operation and maintenance

PEIS Programmatic Environmental Impact Statement

PM10 particulate matter greater than 10 micrometers

8/1/2007 iv USIBWC

Presidio FCP Presidio-Ojinaga Flood Control Project

RCRA Resource Conservation and Recovery Act

Rectification FCP Rio Grande Rectification FCP

ROW right of way

Santa Ana NWR Santa Ana National Wildlife Refuge

SIP state implementation plan

SPCC spill prevention, control, and countermeasures

T&E threatened and endangered

TAC Texas Administrative Code

TARL Texas Archeological Research Laboratory

TPWD Texas Parks and Wildlife Department

TWDB Texas Water Development Board

USACE U.S. Army Corps of Engineers

USBP U.S. Border Patrol

USC U.S. Code

USBR U.S. Bureau of Reclamation

USDA U.S. Department of Agriculture

USEPA U.S. Environmental Protection Agency

USDA U.S. Department of Agriculture

USFWS U.S. Fish and Wildlife Service

USIBWC

United States Section International Boundary and Water Commission

WBC World Birding Center

WMA Wildlife Management Areas

1-1 USIBWC

SECTION 1 1

PURPOSE OF AND NEED FOR ACTION 2

This section describes the background associated with the action, purpose of and need for 3 the action, the scope of the environmental evaluation, and gives a summary description of each 4 project. Figures illustrating location and main features of flood control projects are presented 5 at the end of Section 1 (Figures 1 to 9). 6

1.1 BACKGROUND 7

1.1.1 Scope of the Environmental Review 8

Federal agencies are required to take into consideration the environmental consequences of 9 proposed and alternative actions in the decision-making process under the National 10 Environmental Policy Act (NEPA) of 1969, as amended. The President’s Council on 11 Environmental Quality issued regulations to implement NEPA that include provisions for both 12 the content and procedural aspects of the required environmental analysis. In 1978, the Council 13 on Environmental Quality issued regulations implementing the process (40 Code of Federal 14 Regulations 1500-1508). 15

The United States Section, International Boundary and Water Commission (USIBWC) 16 regulations for implementing NEPA are specified in Operational Procedures for Implementing 17 Section 102 of the National Environmental Policy Act of 1969, Other Laws Pertaining to 18 Specifics Aspects of the Environment and Applicable Executive Orders (46 FR 44083, 19 September 2, 1981). These federal regulations establish both the administrative process and 20 substantive scope of the environmental impact evaluation designed to ensure that deciding 21 authorities have a proper understanding of the potential environmental consequences of a 22 contemplated course of action. 23

This Programmatic Environmental Impact Statement (PEIS) evaluates a range of 24 alternatives for maintenance activities and future improvements to three of the USIBWC flood 25 control projects (FCP) located in Texas, along the Rio Grande. Those flood control projects 26 are: 27

• Rio Grande Rectification Project extending 84.4 miles along the Rio Grande, 28 downstream from American Diversion Dam to Fort Quitman, Texas. For the pusposes 29 of this PEIS, this project is identified as Rectification FCP. 30

• Presidio-Ojinaga Flood Control Project extending over 13.1 river miles of the Rio 31 Grande near Presidio, Texas. Throughout the PEIS this project is abbreviated as 32 Presidio FCP. 33

• Lower Rio Grande Flood Control Project extending 186 river miles on the Rio Grande, 34 from Peñitas, Texas to the Gulf of Mexico, and including 120 miles of interior 35 floodway. Throughout the PEIS this project is abbreviated as Lower Rio Grande FCP. 36

1-2 USIBWC

The PEIS evaluates, at a programmatic level, potential environmental consequences that 1 may result from implementation of a No Action Alternative and three Action Alternatives. The 2 following environmental resources are assessed in the PEIS: water resources, biological 3 resources land use, air quality, noise public health and environmental hazards cultural 4 resources, socioeconomic resources, and cumulative impacts. 5

The PEIS has been prepared by the USIBWC as the lead agency, in cooperation with the 6 U.S. Army Corps of Engineers (USACE) Galveston District, U.S. Bureau of Reclamation 7 (USBR), El Paso Field Office, and U.S. Fish and Wildlife Service (USFWS), New Mexico 8 Ecological Services Office. 9

1.1.2 USIBWC Authority 10

The International Boundary and Water Commission (IBWC), which before 1944 was 11 known as the International Boundary Commission, was created by the Convention of 1889, and 12 consists of a United States Section (the USIBWC) and a Mexican Section (MxIBWC). The 13 IBWC was established to apply the rights and obligations the Governments of the United States 14 and Mexico assumed under the numerous boundary and water treaties and related agreements. 15 Application of the rights and obligations is accomplished in a way that benefits the social and 16 economic welfare of the people on both sides of the boundary and improves relations between 17 the two countries. The mission of the USIBWC has five components, as follows: 18

• Regulation and conservation of waters of the Rio Grande for use by the United States 19 and Mexico through joint construction, operation, and maintenance of international 20 storage dams and reservoirs and plants for generating hydroelectric energy at the dams, 21 and regulation of the Colorado River waters allocated to Mexico; 22

• Distribution of waters of the Rio Grande and the Colorado River between the two 23 countries; 24

• Protection of lands along the Rio Grande from floods through levee and floodway 25 projects and solution of border sanitation and other border water quality problems; 26

• Preservation of the Rio Grande and Colorado River as the international boundary; and 27

• Demarcation of the land boundary. 28

1.2 PURPOSE OF AND NEED FOR ACTION 29

The USIBWC is proposing a range of alternatives for maintenance activities and future 30 improvements to three of its flood control projects located in Texas, along the Rio Grande: the 31 Rectification FCP, Presdio FCP and Lower Rio Grande FCP. The PEIS is being prepared to 32 evaluate these maintenance improvement alternatives that would allow USIBWC to minimize 33 potential environmental impacts and take advantage of environmental and recreational 34 opportunities while meeting its mandate for flood protection, boundary stabilization, and water 35 delivery. 36

Over a 20-year planning period, the USIBWC anticipates the need to improve capabilities 37 or functionality the Rectification FCP, Presidio FCP and Lower Rio Grande FCP. While some 38

1-3 USIBWC

improvements to the flood control projects are already in a planning stage or have been 1 developed at a conceptual level, others represent measures considered feasible but not currently 2 envisioned for implementation. Known or anticipated improvements are typically associated 3 with the projects’ core mission of flood control, boundary stabilization and water delivery. 4 Other improvements are associated with additional goals adopted by the USIBWC in support of 5 the projects’ core mission. Those goals include improvements in water use, quality or 6 conservation, and multipurpose utilization of the projects in support local or regional initiatives 7 for recreational use or environmental improvement. 8

In compliance with NEPA requirements, the USIBWC routinely prepares environmental 9 evaluations of proposed actions, typically in the form of an Environmental Assessment or, 10 when warranted by significance of potential effects, an Environmental Impact Statement (EIS). 11 Because preparation of those environmental evaluations requires specific definition of the 12 proposed action’s characteristics, extent and location, the USIBWC has taken a broad 13 programmatic look at the potential environmental implications of measures to be considered for 14 future implementation. The PEIS documents the affected environment over an entire flood 15 control project area, and assesses potential environmental consequences. 16

The USIBWC will apply the programmatic evaluation of potential impacts as an overall 17 guidance for future environmental evaluations of individual improvement projects whose 18 implementation is anticipated or possible within a 20-year timeframe. Once any given 19 improvement project is identified for future implementation, site-specific environmental 20 documentation will be developed based on project specifications and PEIS findings. 21

For the PEIS evaluation, measures identified as feasible were organized in three action 22 alternatives that reflect the following project goals: 23

1. Measures associated with projects’ mission of flood control, boundary stabilization and 24 water delivery, evaluated under the Enhanced Operation and Maintenance (EOM) Alternative; 25

2. Measures intended to improve water use, quality and conservation, considered under the 26 Integrated Water Resources Management (IWR) Alternative; and 27

3. Measures in support of local or regional initiatives for increased utilization of the project 28 or to improve environmental conditions, evaluated under the Multipurpose Project 29 Management (MPM) Alternative. 30

The PEIS compares potential environmental consequences of the EOM, IWR and MPM 31 alternatives with those expected from continued use of current management and operational 32 practices, evaluated under the No Action Alternative. 33

1.3 INDIVIDUAL PROJECT DESCRIPTION 34

Figure 1 indicates the location of four flood control projects operated by the USIBWC 35 along the United States-Mexico border, three in in Texas, along the Rio Grande, and a fourth 36 one in southern California, the Tijuana River Flood Control Project. Rio Grande flood control 37

1-4 USIBWC

projects under evaluation in the PEIS are illustrated in Figures 2 to 9, and their main features of 1 the described below. 2

1.3.1 Rio Grande Rectification Project 3

The Rio Grande Rectification Project, identified in the PEIS as Rectification FCP, was 4 constructed between 1934 and 1938; it extends 86 river miles from El Paso to Fort Quitman, 5 Texas. The purpose of the project is to stabilize the international river boundary and to provide 6 flood protection for both countries in urban, suburban, and agricultural areas. Figures 2 and 3 7 show the project location and main geographic features and structures along the upper and 8 lower reaches of the Rectification FCP, respectively. 9

The Rectification FCP was constructed by straightening the river channel and developing a 10 narrow floodway by constructing levees on both sides of the river. The channel straightening 11 process removed several meanders and resulted in a reduction in the river length from 155 to 12 86 miles. Four grade control structures were also installed: Island, Tornillo, Alamo, and 13 Guayuco. The average channel depth along the Rectification FCP is 3 to 5 feet. The width of 14 the channel is between 66 and 100 feet and its capacity is 1,000 cfs. The floodway width 15 averages about 590 feet and its capacity is 11,000 cfs. The project includes 85.4 miles of 16 levees on the U.S. side, and 83.7 miles of levees on the Mexico side. The average levee height 17 is 7.2 feet, the average top width is 20 feet. 18

1.3.2 Presidio-Ojinaga Flood Control Project 19

The Presidio FCP was implemented in 1975 to protect productive agricultural lands in the 20 Presidio-Ojinaga Valley from frequent flooding. The project was also intended to establish the 21 international boundary as per the Boundary Treaty of 1970. Figures 4 and 5 show the location 22 of the project and key geographic features. 23

The Presidio FCP provided flood protection by augmenting the capacity of the river 24 channel through the construction of cleared berms and levees on both sides of the river. The 25 project extends for 13.1 miles through Presidio, Texas. Rectification also took place at the time 26 of project construction, reducing the channel length by about 6.3 miles. Levees on the north 27 and south sides of Cibolo Creek are each 145 feet wide, from the landside limit of the right-of-28 way (ROW) to the creek side ROW limit. The levees were designed to contain a 25-year flood 29 with 4 feet of freeboard. Downstream of the confluence with the Rio Conchos, the design flow 30 is 42,000 cfs. The levees downstream of the end of the river relocation were raised 4 feet 31 following the September 1978 flood. 32

There are approximately 15 miles of levee length, including the spur levees. The height of 33 the levees varies from 12 to 35 feet, with the higher at the southern end of the project. The 34 crest width was originally designed to be 16 feet, but is currently between 8 and 12 feet, with 35 the narrower crests at the southern end of the project. 36

1-5 USIBWC

1.3.3 Lower Rio Grande Flood Control Project 1

The Lower Rio Grande FCP extends approximately 186 miles from Peñitas, Texas to the 2 mouth of the river in the Gulf of Mexico. The project was the result of a 1932 agreement 3 between the United States and Mexico to provide flood protection to urban, suburban, and 4 agricultural lands in both countries. Figure 6 shows the overall project location, and individual 5 maps are provided for the upper river reach of the Lower Rio Grande FCP and the Main 6 Floodway (Figure 7), the lower river reach of the Lower Rio Grande FCP (Figure 8), and the 7 North and Arroyo Colorado Floodways (Figure 9). 8

The Lower Rio Grande FCP consists of the river channel, flood levees in each country, two 9 diversion dams, and off-river floodways in Mexico and the United States. Some river 10 straightening took place between 1976 an 1977 on a 9,000-foot length of river upstream of 11 Hidalgo and Reynosa. The depth of the river channel varies from 1 to 15 feet. 12

Two diversion dams, Anzalduas and Retamal, were constructed to route most of the flood 13 flows in the off-river floodway systems of the United States and Mexico, respectively. 14 Anzalduas Dam also diverts irrigation flows into Mexico. The interior floodway system in the 15 United States has a total area of 27,013 acres between the levees in Hidalgo, Cameron, and 16 Willacy Counties. 17

The United States portion of the project includes102 miles of levees along the Rio Grande, 18 and 168 miles in an off-stream, interior floodway system. This off-stream system initiates in 19 the Main Floodway which subsequently separates into the North Floodway and the Arroyo 20 Colorado Floodway at the City of Mercedes. The levee system has an average levee height of 21 approximately 15 feet, an average base width of 90 to 120 feet, and an average crown width of 22 14 to 16 feet. Levee separation is between 600 feet to 1 mile. 23

The project was designed and built for a flood of 250,000 cfs at Rio Grande City. During 24 the design flood, 105,000 cfs would be diverted to the United States’ off-river floodways at 25 Anzalduas Dam, and 105,000 cfs would be diverted to Mexico’s off-river floodway system at 26 Retamal Dam. Diversion of flows at the two dams and water losses between Rio Grande City 27 and the diversions would result in the passage of a maximum of 20,000 cfs through the 28 Brownsville-Matamoros area. 29

Lower Rio Grande Flood Control Project

Presidio-Ojinaga Flood Control Project

Rio Grande Rectification Project

Tijuana River Flood Control Project

G ulf of California

Paci fic O cean

Gulf of Mexico

El Paso

Texas

Arizona New Mexico

Oklahoma

California

KansasColorado Utah

Arkansas

Nevada Missouri

Louisiana

Sonora

Chihuahua

Durango

Coahuila De Zaragoza

Sinaloa Nuevo Leon

Baja California Sur

Tamaulipas

Zacatecas

Baja California Norte Rio Grande

Nazas

Conchos

Rio SaladoYa qu i

Ri o

So no ra

Rio Fuerte

Ba vi sp e

Papigochic

M oc te zu m a

Ya qu i

San Lorenzo

RedBrazos

Ri o

G ra nd e

Gila

Pe co s

Arkansas

Canadian

Salt

Colorado

La Paz

Culiacan

Saltillo

Chihuahua

Monterrey

Hermosillo

Tulsa

Austin

Tucson Dallas

Houston

El Paso

Phoenix

Wichita

San Diego

Las Vegas

Fort Worth

San Antonio

Los Angeles

Albuquerque Oklahoma City

Corpus Christi

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Figure 1 Location of USIBWC Projects

Programmatic EIS International Boundary and Water Commission, United States Section¹ 0 100 200 300 400 50050 Miles

0 200 400 600 800100

Scale = 1: 6,200,000

106°30'0"W

106°0'0"W

106°30'0"W

106°0'0"W

31°30'0"N

31°30'0"N

Figure 2 Rio Grande Rectification Project - Upper Reach

Programmatic EIS International Boundary and Water Commission, United States Section¹ 0 2 4 6 81 Miles

0 3 6 9 121.5 Kilometers

Scale = 1: 200,000

Dona Ana County

Otero County

El Paso County Hudspeth County Culberson County

Rio Grande

Chihuahua

MEXICO

Texas

UNITED STATES

New Mexico Juarez

UNITED STATES

Socorro

El Paso

Las Cruces

U ppe r Rea ch

Lo wer Reach

Irrigated Areas

Floodway

Urban Areas

Military Reservation

LEGEND

106°0'0"W

105°30'0"W

31°30'0"N

31°0'0"N

106°0'0"W

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31°0'0"N

Fi gu re 3 Rio Grande Rectification Project - Lower Reach

Programmatic EIS International Boundary and Water Commission, United States Section¹ 0 2 4 6 81 Miles

0 3 6 9 121.5 Kilometers

Scale = 1: 200,000

Dona Ana County

Otero County

El Paso County Hudspeth County Culberson County

Rio Grande

Chihuahua

MEXICO

Texas

UNITED STATES

New Mexico Juarez

UNITED STATES

Socorro

El Paso

Las Cruces

U ppe r Rea ch

Lo wer Reach

Irrigated Areas

Floodway

Urban Areas

Military Reservation

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29°30'0"N104°30'0"W 104°25'0"W

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29°35'0"N

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Figure 4 Presidio - Ojinaga Flood Control Project

Programmatic EIS International Boundary and Water Commission, United States Section¹ 0 0.5 1 1.5 20.25 Miles

0 1 2 30.5

Scale = 1: 200,000

Mile 0

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Fi gu re 5 Pr esi di o - O ji na ga Fl o od C o ntro l P ro jec t, Ae ria l P ho tog raph y

Programmatic EIS International Boundary and Water Commission, United States Section¹ 0 0.5 1 1.5 20.25 Miles

0 1 2 30.5 Kilometers

Scale = 1: 200,000

Ojinaga

Presidio

LRGFCP Upper River Reach and Main Floodway

LRGFCP North and Arroyo Colorado Floodways

LRG

FCP Low er Ri ver R each

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Figure 6 Lower Rio Grande Flood Control Project

Overview Map Programmatic EIS

International Boundary and Water Commission, United States Section¹ 0 4 8 12 162

Miles

0 5 10 15 202.5

Scale = 1: 400,000

98°30'0"W 98°0'0"W

98°0'0"W

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Figure 7 LRGFCP Upper River Reach and Main Floodway

Programmatic EIS International Boundary and Water Commission, United States Section¹ 0 2 4 6 81 Miles

0 2.5 5 7.5 101.25 Kilometers

Scale = 1: 400,000

Irrigated Areas

Floodway

LEGEND

Urban Areas

BEGIN LRGFCP

97°30'0"W

26°0'0"N

26°0'0"N

Figure 8 LRGFCP Lower River Reach

Programmatic EIS International Boundary and Water Commission, United States Section¹ 0 2 4 6 81 Miles

0 2.5 5 7.5 101.25 Kilometers

Scale = 1: 400,000

Irrigated Areas

Floodway

LEGEND

LRGFCP ENDS

Figure 9 LRGFCP No rt h an d Arroyo Col or ado F lo od wa ys

Programmatic EIS International Boundary and Water Commission, United States Section¹ 0 2 4 6 81 Miles

0 2.5 5 7.5 101.25 Kilometers

Scale = 1: 400,000 Irrigated Areas

Floodway

2-1 USIBWC

SECTION 2 1

FORMULATION OF ALTERNATIVES 2

This section describes how the alternatives were initially identified and processed 3 through the USIBWC, interested stakeholders and government agencies. It further identifies the 4 formulation process to arrive at the alternatives evaluated in the PEIS. 5

2.1 INITIAL IDENTIFICATION OF POTENTIAL MEASURES 6

Potential actions and alternatives identified for each flood control project were initially 7 identified by the Engineering, Operations and Environmental Divisions of the USIBWC. A 8 summary description of those actions and alternatives was provided for comment to agencies, 9 state and local governments, organizations, and other potential stakeholders as part of a public 10 scoping process. Findings and conclusions of this process, described in more detail in Section 11 3.1, were compiled by the USIBWC in the 2005 document Scoping Meeting Summary, 12 Programmatic Environmental Impact Statement, Rio Grande and Tijuana River Flood Control 13 Projects. Comments and recommendations submitted during the scoping process were then 14 incorporated into a revised set of preliminary alternatives for evaluation in the PEIS. 15

Measures initially identified during PEIS development and scoping meetings were 16 consolidated to reflect four major objectives of the flood control projects: 17

• Ongoing and future activities associated with the flood control mission of all 18 projects, namely those associated with maintenance and improvements to the levee 19 system and floodways. 20

• Ongoing and future activities specifically associated with the water deliveries and 21 boundary preservation mission, in accordance with regional and international 22 obligations. Those activities are primarily associated with channel maintenance 23 and sediment removal and management, and apply to the three Rio Grande flood 24 control projects. 25

• Activities associated with management of water resources such as water quality, 26 use and conservation. While this is not a goal inherently associated with the flood 27 control and water delivery project mission, it reflects strategic goals adopted by the 28 USIBWC as an integral part of improved project functionality and cooperation with 29 local initiatives. 30

• Activities associated with potential multipurpose use of the projects, such as 31 additional floodway utilization for purposes other than optimization of flood 32 control, as well as regional environmental initiatives outside the USIBWC 33 jurisdiction. These initiatives would be implemented and managed by other 34 agencies or organizations, and supported through cooperative agreements. 35

Table I-2.1 presents a summary of potential measures identified for improvement of the 36 Rio Grande flood control projects. Measures are listed according to the main project 37 objectives. Potential applicability of a measure to a given project is also indicated. 38

2-2 USIBWC

Table I-2.1 Potential Changes Relative to Current O&M Practices 1

FLOOD CONTROL PROJECT

Rectification Presidio LRGFCP

FLOOD CONTROL SYSTEM ALONG THE RIO GRANDE

Levee Improvements Levee height increase X X X Structural levee improvements X X X Partial relocation within ROW or new flood easements X

Changes in Floodway Management Streambank stabilization with vegetation combined with mechanical means Changes in vegetation removal and timing/extent of mowing X Agricultural/grazing use Restricted Use Zones X

Changes in Channel Maintenance Sediment removal and disposal X X X Debris removal Shore/aquatic vegetation removal X New/changes to diversion structures

INTEGRATED WATER RESOURCES MANAGEMENT

Water Use and Conservation Salt cedar management X X Revegetation with low-water use species Irrigation BMPs to increase water delivery efficiency X Wetlands improvement Support maintenance of irrigation structures and drains X

Water Quality Water quality monitoring Modified irrigation drain maintenance X X Limited floodway revegetation to reduce erosion and sediment load

MULTIPURPOSE PROJECT MANAGEMENT

Jurisdictional Floodway Use Non-USIBWC floodway maintenance Parks, nature trails, recreational areas X X Control of invasive/exotic species X X Wildlife habitat conservation Establish/improve riparian corridors

Cooperative Agreements and Regional Initiatives Vegetation removal and timing/extent of mowing X Control of invasive/exotic species outside ROW X X Wildlife habitat conservation inside or outside ROW X X X Increase backwaters at mouth of arroyos to increase aquatic habitat Reconnection of historic, low-elevation meanders for aquatic habitat Levee setbacks at flood prone areas for increased habitat Flow regime modification to provide year-round baseflow X Watershed management for sediment control Upstream sediment control (dams, traps) X X 2

2-3 USIBWC

2.2 BASIS FOR ALTERNATIVES FORMULATION 1

Feasible and likely beneficial measures were identified on the basis of opportunities and 2 constraints for inclusion in the evaluation of potential impacts. The resulting analysis excluded 3 from evaluation those actions that are in conflict with the project objectives, or small-scale 4 measures with minimum potential impacts or environmental benefit. A summary of key 5 considerations for each individual project is presented in Table I-2.2 and briefly discussed 6 below. 7

Table I-2.2 Opportunities and Constraints for Project Improvement 8 Lower Rio Grande Flood Control Project

Opportunities and Constraints

Rio Grande Rectification

Project

Presidio-Ojinaga Flood Control

Project River

Segment Interior

Floodways

Flood control objective Yes Yes Yes Yes

Primary control of floodway management USIBWC USIBWC

Federal and state natural agencies /

Private / NGOs

USIBWC for use as flood easements Water delivery and boundary stabilization Yes Yes Yes No

Dry-weather base flow Minimum, largely used upstream

Low flow, seasonally variable

Continuous, seasonally variable

Agricultural and municipal return flows Scale 86 miles 13 miles 186 miles 120 miles Vegetation and wildlife habitat

Relatively diversified

Relatively diversified

Very diversified

Low diversification

Environmental issues Limited and mostly known issues

Few and mostly known issues

Complex issues partially addressed

Few and mostly known issues

Ongoing environmental initiatives for floodway use

Few Few Multiple by agencies and organizations Small-scale only

Potential for additional multipurpose use Moderate Very limited Moderate Very limited

2.2.1 Flood Control 9

Flood control is a common element to all projects. The need for improved flood control 10 has been identified for the Rectification FCP, Presidio FCP, and Lower Rio Grande FCP. For 11 the Lower Rio Grande FCP, levee improvements are needed, both for the river levee system 12 and for the interior floodways. Implementation of improvements is underway for upstream 13 reach of the levee system, and others are scheduled for implementation in the downstream 14 reach over the next 3 years. Evaluations of potential levee deficiencies have been completed 15 for the Rectification and Presidio FCPs. 16

Floodway management is a key component of flood control that restricts extensive 17 vegetation development. Floodways in the Rio Grande Rectification and Presidio FCPs are 18 almost entirely under USIBWC management control, providing opportunities for 19 implementation of environmental improvements. In the Rio Grande reach of the Lower Rio 20

2-4 USIBWC

Grande FCP, however, USIBWC jurisdiction is largely limited to narrow corridors along the 1 stream bank and flood control levees; most of the floodway is under private ownership for 2 agricultural use or natural resources management agencies and organizations. Management of 3 the Lower Rio Grande FCP interior floodways, largely used for agriculture, is controlled by the 4 USIBWC as flood easements. 5

2.2.2 Water Delivery and…