Final_EIS.pdf

River Management Alternatives for the Rio Grande Canalization Project

June 2004

Technical Support:

PARSONS

Austin, Texas

Cooperating Agency:

U.S. Department of the Interior

Bureau of Reclamation Albuquerque, New Mexico

Lead Agency:

United States Section, International Boundary and Water Commission El Paso, Texas

FINAL ENVIRONMENTAL IMPACT STATEMENT

FINAL ENVIRONMENTAL IMPACT STATEMENT

River Management Alternatives for the Rio Grande Canalization Project

Lead Agency:

UNITED STATES SECTION,

INTERNATIONAL BOUNDARY AND WATER COMMISSION

Cooperating Agency:

U.S. DEPARTMENT OF THE INTERIOR,

BUREAU OF RECLAMATION, ALBUQUERQUE AREA OFFICE

Albuquerque, New Mexico

Technical Support:

PARSONS

Austin, Texas

June 2004

Cover Sheet

River Management Alternatives for the Rio Grande Canalization Project ( ) Draft (X) Final

Lead Agency United States Section, International Boundary and Water Commission, United States and Mexico (USIBWC) El Paso, Texas.

Cooperating Agency U.S. Department of the Interior, Bureau of Reclamation, Albuquerque Area Office, Albuquerque, New Mexico.

Abstract The USIBWC is evaluating long-term river management alternatives for the Rio Grande Canalization Project (RGCP), a 105.4-mile narrow river corridor that extends from below Percha Dam in Sierra County, New Mexico to American Dam in El Paso, Texas. The RGCP, operated and maintained by the USIBWC since its completion in 1943, facilitates water deliveries and provides flood control.

The No Action Alternative and three action alternatives are evaluated in the EIS. The alternatives were developed in a manner that enhances and partially restores the riparian ecosystem while maintaining the flood control and water delivery requirements of the RGCP.

Alternatives formulation was the result of a 3-year public consultation process that included regulatory agencies, irrigation districts, and environmental organizations.

Measures under consideration as part of the alternatives include modifications to grazing leases, changes in floodway vegetation management, riparian restoration, and aquatic habitat diversification.

Following the public comment period on the Draft EIS, the Integrated USIBWC Land Management was identified as the preferred alternative for RGCP management.

Other Requirements Served This Final EIS is intended to serve other environmental review and consultation requirements pursuant to: 40 CFR 1502.25(a)

Date Draft EIS was made available to EPA and the Public:

December 18, 2003

Date Final EIS was made available to EPA and the Public:

June 29, 2004

Final EIS – River Management Alternatives for the Rio Grande Canalization Project (RGCP) Preface

PREFACE

This document is an abbreviated Final Environmental Impact Statement (Final EIS) for long-term river management alternatives of the Rio Grande Canalization Project (RGCP). An abbreviated Final EIS is one that provides responses to comments provided by agencies and the general public, along with additions and modifications to selected Draft EIS sections. No modifications are needed in the remaining Draft EIS sections and, thus, are not reprinted with the Final EIS. Also provided are an Executive Summary and appendices with additional technical information. The Final EIS content is described below.

Executive Summary The Executive Summary is an update of the version previously provided in the

Draft EIS. It includes additional information on the Draft EIS review process, and USIBWC’s selection of a preferred alternative for long-term management of the RGCP.

Draft EIS Additions and Modifications Chapter I contains additions and modifications to the Draft EIS as follows:

• A more detailed subsection was included on USIBWC authority to adopt a modified management strategy for the RGCP (Subsection 1.1.3).

• Two new sections were added to incorporate information following release of the Draft EIS: Selection of a Preferred Alternative (Section 2.13), and Draft EIS Public Review Period (Subsection 5.1.4).

• Updated sections were included on water quality baseline conditions (Subsection 3.1.3); summary analysis of potential effects on water resources and land use (Subsections 4.1.2 and 4.8.2, respectively); a revised socioeconomic analysis, including potential effects by individual county (Section 4.9); and analysis of cumulative effects of regional plans (Subsection 4.15.1).

Responses to Draft EIS Comments Chapter II of the Final EIS presents responses to comments from agencies and the public received during the Draft EIS review period (December 26, 2003 to March 1, 2004). Responses are presented sequentially by EIS section, following the numbering system used in the Draft EIS. The introduction to Chapter II describes the numbering system used to track comments, and to cross-reference those comments to the EIS section in which they are addressed.

Additional Appendices The Final EIS contains six new appendices, as listed below. These appendices follow the numbering sequence presented in the Draft EIS.

Rio Grande Canalization Project (RGCP) Preface

June 2004

Appendix J, Cross-Reference Index Between Comments and Responses. This appendix provides a cross-reference index to locate responses to individual comments previously discussed in Chapter II. The index lists commentator, comment tracking number, and EIS section in which each comment was addressed. The commentators sequence follows four main categories: Agencies, Organizations, Private Business, and Individual Stakeholders (Codes A, O, P and S, respectively).

Appendix K, Draft EIS Comments. This appendix presents copies of all correspondence submitted by agencies, organizations, and individual stakeholders during the Draft EIS review period. Individual comments identified are numbered in the correspondence for cross-referencing with responses provided (Appendix J).

Appendix L, Public Hearing Transcript. This appendix provides the official Public Hearing transcript. Individual comments made at the end of the hearing are also numbered for cross-referencing with responses provided (Appendix J).

Appendix M, Additional Cultural Resources Consultation. This appendix presents the USIBWC transmittal letter of the 2001 Cultural Resource Report, and comments received from the New Mexico Department of Cultural Affairs, Historic Preservation Division on May 10, 2004, following review of the document. These comments are also numbered for cross-referencing with responses provided (comments identified as A5b in Appendix J).

Appendix N, Socioeconomic Effects Analysis Support Documentation. This appendix presents additional support documentation for the socioeconomic effects analysis. This information was used on the update of Section 4.9.

Appendix O, Act of Congress Authorizing USIBWC to Construct, Operate and Maintain the RGCP. This appendix presents the text of Act of August 29, 1935 (49 Stat.

961) and Act of June 4, 1936 (49 Stat. 1463).

Appendix P, USFWS Letter of Concurrence with Findings of the RGCP Biological Assessment. This appendix presents the text of the June 28, 2004 letter from the U.S.

Fish and Wildlife Service addressing issues identified in the Biological Assessment for the RGCP.

Appendix Q, Final EIS and Technical Support Documents. This appendix, provided in CD format, presents the electronic version of the Final EIS, the December 2003 Draft EIS, and the following technical documentation prepared in support of the EIS: January 2004 Biological Assessment; August 2003 Reformulation of River Management Alternatives; and March 2001 Alternatives Formulation Report (the last two reports were also provided in Appendix I of the Draft EIS).

Rio Grande Canalization Project (RGCP) Executive Summary

ES-1 June 2004

EXECUTIVE SUMMARY

Purpose of and Need For Action The United States Section of the International Boundary and Water Commission

(USIBWC) is evaluating long-term river management alternatives for the Rio Grande Canalization Project (RGCP), a narrow river corridor that extends 105.4 miles along the Rio Grande, from below Percha Dam in Sierra County, New Mexico to American Dam in El Paso, Texas. The RGCP, operated and maintained by the USIBWC since its completion in 1943, was constructed to facilitate water deliveries to the Rincon and Mesilla Valleys in New Mexico, El Paso Valley in Texas, and Juárez Valley in Mexico, and provide flood control. A levee system for flood control extends 57 and 74 miles over the right and left stream banks, respectively. Figure ES-1 shows the RGCP location.

The USIBWC currently implements operation and maintenance procedures to enhance ecosystem functions within the RGCP. However, the river and floodway will remain highly altered from events pre-dating RGCP construction. Thus, the USIBWC recognizes the need to accomplish flood control, water delivery, and operation and maintenance activities in a manner that enhances or restores the riparian ecosystem.

River management alternatives under consideration address practices such as stream bank stabilization, erosion reduction, and flood control as well as environmental measures intended to support restoration of native riparian vegetation and diversification of aquatic habitats along the RGCP. Potential effects of the alternatives were evaluated in a Draft EIS released for agency and public review on December 18, 2003.

Alternatives Considered in Detail Throughout an extended public consultation process, an interdisciplinary team considered several river management alternatives and selected four for detailed analysis.

Features of these alternatives are described below. Alternatives were initially formulated in a March 2001 report issued following an 18-month stakeholder consultation period, and subsequently modified to address further input from representatives of regulatory agencies, irrigation districts, environmental organizations, and the general public. A Reformulation of River Management Alternatives Report documenting those modifications and the rationale for their adoption was completed in August 2003 as the basis for the Draft EIS.

Table ES-1 presents a comparison of measures by management category for the No Action Alternative and three action alternatives. Levee rehabilitation is the core action of the Flood Control Improvement Alternative, along with changes in grazing leases to improve erosion control. These two measures apply to all action alternatives. Most other measures under consideration are associated with floodway management under the Integrated USIBWC Land Management Alternative and Targeted River Restoration Alternative. The latter alternative also considers measures for aquatic habitat diversification such as modified dredging of arroyos and reopening of meanders, as well as riparian vegetation development by induced overbank flows.

ES-2 June 2004

No Action Alternative The No Action Alternative would continue RGCP operation and maintenance activities as currently conducted by the USIBWC. Those activities are directed toward flood protection and water delivery, with some activities involving environmental improvements. Key features of this alternative are management of the levee system, floodway maintenance through mowing, grazing leases and recreational areas;

maintenance of pilot channel and irrigation facilities; and sediment control and disposal.

Mowing of the floodway is conducted annually, or as circumstances warrant, to control weeds, brush, and tree growth, including salt cedar. The USIBWC administers a land lease program that covers approximately 43 percent of the RGCP floodway. Pilot channel maintenance is performed during non-irrigation periods when water levels are lowest by removing debris and deposits, including sand bars. The USIBWC is also responsible for maintaining five NRCS sediment control dams in tributary arroyos and associated access roads. The agency conducts dredging at the mouth of arroyos to maintain grade of the channel bed and ensure the channel conveys irrigation deliveries.

Flood Control Improvement Alternative This alternative takes into consideration a potential increase in flood containment capacity. A 1996 hydraulic modeling study by the U.S. Army Corps of Engineers (USACE) identified a number of potential deficiencies in the RGCP in the event of a 100-year flood. Those findings were partially re-evaluated as part of the Draft EIS to include potential effects of environmental measures such as additional vegetation growth in the floodway. Most of the potential levee deficiencies were identified within urbanized reaches of the RGCP.

The assumption used for the Draft EIS was that existing levees would be raised as needed to meet a 3-foot freeboard design criteria, and new levees would be constructed in unconfined areas where flood levels could extend past the right-of-way (ROW) boundary.

Based on this assumption, levee rehabilitation included 60.1 miles of levees needing a 2-foot average height increase, 6 miles of new levees, and a 2.8-mile long floodwall in the Canutillo area. As part of this alternative, the grazing lease management program would be modified to improve erosion control. The modified program would include a variety of vegetation treatments to control salt cedar in lease areas.

Integrated USIBWC Land Management Alternative In addition to measures for flood control improvement and erosion protection, this alternative incorporates environmental measures within the floodway. All environmental measures would be limited to lands under USIBWC jurisdiction. A key feature of the Integrated USIBWC Land Management Alternative is development of a riparian corridor for bank stabilization and wildlife habitat by planting and stream bank reconfiguration at selected locations. Stream bank reconfiguration would allow overbank flows within the floodway to provide conditions suitable for establishment of native riparian species, particularly cottonwoods. Under this alternative, currently mowed floodway vegetation would be managed to promote native grass development in combination with salt cedar control treatments.

Las Cruces

Doña Ana County

Otero County

Luna County

Sierra County

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Caballo

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Caballo Resevoir

Percha Dam

Mesilla Diversion Dam

Leasburg Diversion Dam

American Diversion Dam

0 10 20 30 405 Kilometers

0 6 12 18 243 Miles

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Location of the Rio Grande Canalization Project (RGCP)

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Figure ES-1

ES-3

Final EIS – R iver Management Alternatives for the

ES-4 June 2004

Table ES-1 Comparison of Alternative Features

Management Category

No Action Alternative

Flood Control Improvement

Alternative

PREFERRED

ALTERNATIVE:

USIBWC Land Management

Targeted River Restoration Alternative

Routine levee and road maintenance No change No change No change

Levee System Management n/a Levee system improvements

Levee system improvements

Levee system improvements

Unmodified grazing leases

Modified leases for erosion control

(3,552 ac)

Modified leases for erosion control

(3,552 ac)

Modified leases for erosion control

(3,493 ac)

Continued mowing (2,674 ac)

Continued mowing (2,223 ac)

Modified grassland management

(1,641 ac)

Modified grassland management

(1,641 ac)

Native vegetation planting (223 ac)

Native vegetation planting (189 ac)

Continue seasonal mowing

(4,657 ac) No change

Steram bank reconfiguration

(127 ac)

Seasonal peak flows / bank preparation

(516 ac)

Floodway Management n/a n/a n/a Voluntary conservation easements (1,618 ac)

Debris removal and channel protection No change No change No change

America Dam and irrigation structures maintenance No change No change No change

Channel and Irrigation Facilities

Management n/a n/a n/a Reopening of six former meanders

(147 ac)

NRS sediment dam maintenance No change No change No change

Sediment removal from arroyos / mitigation actions No change No change

Modified arroyo dredging for aquatic habitat (12 arroyos)

Disposal from dredging channel within ROW*

Disposal mainly outside ROW*

Disposal mainly outside ROW*

Disposal mainly outside ROW*

Sediment Management n/a n/a

Disposal from environmental measure excavation inside

ROW*

Disposal from environmental measure excavation inside ROW*

*ROW of the Rio Grande Canalization Project (lands under USIBWC jurisdiction)

ES-5 June 2004

Targeted River Restoration Alternative This alternative emphasizes environmental measures associated with partial restoration of the RGCP, such as induced overbank flows to promote riparian corridor development, and opening of meanders and modification of the mouth of arroyos to increase aquatic habitat diversification. This alternative includes measures previously identified for flood control improvement and grazing leases modification.

Vegetation management for this alternative includes planting and enhancement of existing native woody vegetation and modified grassland management, as previously indicated for the Integrated USIBWC Land Management Alternative. These measures would be complemented by use of seasonal peak flows to promote natural regeneration of riparian bosque, and the use of conservation easements.

Seasonal peak flows are controlled water releases from Caballo Dam during high storage conditions in Elephant Butte Reservoir to induce overbank flows. Environmental measures would extend beyond the ROW through use of voluntary conservation easements to preserve existing wildlife habitat and encourage native bosque development.

Partial reopening of six former meanders eliminated during construction of the RGCP would be conducted to diversify aquatic habitat required for breeding and spawning of native fish species. In addition, dredging of some arroyos would be modified to create backwaters for diversification of aquatic habitats.

Implementation Strategy Program Management. Use of adaptive management is anticipated in implementing river management alternatives. Adaptive management is a science-based decision process that leads to better management through a systematic process of prediction, application, monitoring, feedback, and improvement.

It is envisioned that adaptive management would be implemented through coordination with the Paso del Norte Watershed Council established by the New Mexico- Texas Water Commission. The Council would serve in an advisory capacity regarding selection, planning, and implementation of environmental measures in accordance with the objectives of the Council, and within the limits of the available manpower and resources. It would also recommend policies for cooperation and sharing information concerning planning and management activities of other projects potentially affecting the operation and management of the RGCP. Guidance for future project needs and measures would be provided by an External Advisory Group to obtain impartial, scientifically informed evaluations based on a long-term monitoring and evaluation program.

Water Acquisition and Cooperative Programs. Because a number of environmental measures under consideration would result in water consumption, water rights acquisition and cooperation with the irrigation districts are critical elements in the viability and long-term sustainability of environmental measures. Given that the USIBWC does not have any water rights within the RGCP, options for acquisition were evaluated. Support of water conservation by financing on-farm water conservation

ES-6 June 2004 programs, was identified as the most viable strategy to secure water. Conservation programs would not only be consistent with stated interests and ongoing programs of the irrigation districts, but would also facilitate seeking funds from high-priority state and federal programs. Cooperation agreements would be established with other agencies for increased sediment control at a watershed level, and to secure and manage voluntary conservation easements.

Implementation Timetable. Levee rehabilitation, improvements in erosion control, establishment of a riparian corridor and diversification of aquatic habitats are envisioned as long-term processes that will evolve as the effectiveness of individual projects are documented. A 20-year timeline was adopted for implementation of alternatives under consideration. During an initial 5-year phase, implementation plans would be developed and funded, agreements would be reached for interagency cooperation and water acquisition, selected projects would be tested at a pilot scale, and monitoring would be conducted. Priority projects would be implemented during a second 5-year phase. A 10-year final phase would be used for implementation of the remaining projects.

Potential Effects of the Alternatives Thirteen resource areas were evaluated to assess potential effects of the river management alternatives. For each resource area, evaluation criteria were identified and applied to the various measures under consideration. Table ES-2 presents a comparison of alternatives in terms of potential effects on resources most likely to be affected by changes in river management under consideration.

Preferred Alternative The USIBWC selected the Integrated USIBWC Land Management Alternative as the agency’s preferred approach for long-term management of the RGCP. In selecting the preferred alternative, the agency reviewed the predicted environmental, economic, and social impacts of three action alternatives and the No Action Alternative; their anticipated environmental and financial ability to be implemented, and quality of life performances; and the risks and safeguards inherent in them. It is believed that the Integrated USIBWC Land Management Alternative will bring actual results in the short and medium term as it:

• Allows the USIBWC to re-assess floodway management within the context of current functions;

• Gradually develops environmental improvements within its jurisdictional area with manageable water consumption;

• Puts in place some agreements with other agencies and, hopefully, water users and environmental organizations; and

• Would not be cost prohibitive.

A Record of Decision (ROD), indicating selection of a river management alternative for the RGCP and rationale for the decision, will be published in the Federal Register 1 month after the Final EIS release date for agency and public review.

ES-7 June 2004

Table ES-2 Summary Comparison of the Effects of the Alternatives

Resource Area

No Action Alternative

Flood Control Improvement Alternative

Integrated USIBWC Land Management Alternative

Targeted River Restoration Alternative

Water Resources No-mow zones would be maintained, with a potential consumption of up to 35.3 ac-ft/yr No effects on water delivery or water quality are anticipated as current practices would be maintained.

A potential 1,078 ac-ft/yr increase in water consumption due to environmental measures. Water consumption would increase.

No effects on water delivery are anticipated for levee system rehabilitation, or changes in grazing leases in uplands.

Water quality could decrease in terms of total suspended solids during construction, but it would improve in the long-term by a reduced sediment load and lower nutrient input from grazing areas with improved vegetative cover.

A potential water consumption increase of 2,203 ac-ft/yr at the completion of the 20-year implementation period. This represents 0.34% of EBID full diversion allocation, or 1.5% in severe drought conditions (as in 2003) Development of riparian vegetation on stream banks would have a long-term positive effect on water delivery by stabilization of stream banks. Short-term increases in debris and sediment in the river would be expected prior to establishment of vegetative cover.

Water quality is likely to improve as more extensive vegetative cover on the RGCP floodway and uplands improve erosion control and nutrient release from grazing areas.

A potential for a water consumption increase of approximately 9,461 ac-ft/yr at the completion of the 20-year implementation period. This value would be equivalent to 1.91% of EBID full diversion allocation (releases would not be possible during drought conditions).

Effects on water delivery and water quality would be similar to those of the Integrated USIBWC Land Management Alternative.

Flood Control The risk of flooding and overtopping the levees from the 100-year flood would remain as currently quantified.

Additional protection would be provided to life and public and private property beyond that which is already provided by the existing levee system.

The potential freeboard increase in levee deficient areas would be approximately 2 feet.

Similar to the Flood Control Improvement Alternative. There would also be a potential for a small reduction in flood containment capacity due to increased vegetation growth along the floodway. The potential freeboard increase in levee deficient areas would increase to approximately 2.5 feet.

Similar to the Flood Control Improvement Alternative. There would also be a potential for a small reduction in flood containment capacity due to increased vegetation growth along the floodway. The potential freeboard increase in levee deficient areas would increase to approximately 2.5 feet.

Soils No change from baseline condition.

Levee rehabilitation would mobilize 898 ac-ft of soil for construction.

Modified grazing leases would reduce uplands erosion 0.45 ac-ft annually and improved riparian conditions by reducing bank erosion and increasing ground cover.

Levee rehabilitation and modified grazing leases would result in similar effects as the Flood Control Improvement Alternative.

An additional 157 ac-ft of soil would be displaced as a result of bank shave-downs. Mitigation procedures were established to reduce erosion.

Levee rehabilitation and modified grazing leases would result in similar effects as the Flood Control Improvement Alternative. An additional 300 ac-ft of soil would be displaced as a result of opening former meanders, excavating arroyos and scour during seasonal peak flows. Mitigation procedures were established to reduce erosion.

ES-8 June 2004

Area

No Action Alternative

Flood Control Improvement Alternative

Integrated USIBWC Land Management Alternative

Targeted River Restoration Alternative

Vegetation and Wetlands

No change from baseline condition.

Modified grazing in uplands and riparian zones would affect 3,552 acres increasing plant species, richness and structural diversity.

Levee construction would have a minor effect on vegetation communities.

Mowing by USIBWC would continue at the same level as the No Action Alternative.

Effects of modified grazing leases and levee construction would be similar to the Flood Control Improvement Alternative.

Mowing by USIBWC would be reduced by 1,983 acres.

Restoration of 350 acres of native bosque by bank shavedowns and plantings, and development of native grasslands (1651 acres) would increase the amount of native vegetation within the ROW.

Wetland areas would increase by 13 acres.

Effects of modified grazing leases and levee construction would be similar to the Flood Control Improvement Alternative.

Mowing by USIBWC would be reduced by 2,434 acres.

Restoration of 1,549 acres of native bosque by seasonal peak flows, opening meanders, plantings and development of native grasslands (1,029 acres) would increase the amount of native vegetation within and outside the ROW.

Wetland areas would increase by 96 acres.

Conservation easements would add 1,601 acres under management.

Wildlife Habitat No change from baseline condition.

Wildlife habitat quality would increase 30% due to modified grazing in 3,552 acres of uplands and riparian areas.

However, the majority of the ROW would continue to be considered as below average to poor wildlife quality due to mowing of vegetation.

Construction associated with levee rehabilitation would be a short minor effect.

Modification of salt cedar management in grazing leases methods would result in long-term beneficial effects.

Wildlife habitat quality would increase 51% due to modified grazing in 3,552 acres of uplands and riparian areas, and development of 350 acres of native bosque and 1,641 acres of native grassland.

Construction associated with levee rehabilitation and environmental measures would be a short minor effect.

Modification of salt cedar management in grazing leases methods would result in long-term beneficial effects.

Wildlife habitat quality would increase 72% due to modified grazing in 3,493 acres of uplands and riparian areas, and development of 1,549 acres of native bosque and 1,929 acres of native grassland. A total of 1,618 acres of conservation easements significantly increases the amount of high quality wildlife habitat.

Construction associated with levee rehabilitation and environmental measures would be a short minor effect

Modification of salt cedar management methods for grazing leases would result in long-term beneficial effects.

ES-9 June 2004

No Action Alternative

Flood Control Improvement Alternative

Integrated USIBWC Land Management Alternative

Targeted River Restoration Alternative

Endangered and Other Special Status Species

No change from baseline condition.

Levee construction activities would not affect endangered and other special status species .

Modified grazing in uplands and riparian would benefit some species of concern (SOCs).

Levee rehabilitation and modified grazing leases would result in similar effects as the Flood Control Improvement Alternative.

Development of native bosque using bank shavedowns could potentially create suitable southwestern willow flycatcher habitat and benefit some SOCs.

Levee rehabilitation and modified grazing leases would result in similar effects as the Flood Control Improvement Alternative.

Development of native bosque along meanders could potentially create suitable southwestern willow flycatcher habitat and benefit some SOCs.

Suitable habitat for listed species may exist within conservation easements outside the ROW.

Aquatic Biota No change from baseline condition.

No significant change from baseline condition would occur.

The RGCP would continue to be characterized as poor aquatic habitat, however modified grazing in the riparian area would beneficially effect stream bank stability, water quality and stream side vegetation.

No significant change from baseline condition would occur.

The RGCP would continue to be characterized as poor aquatic habitat, however modified grazing in the riparian area in conjunction with bosque development would beneficially effect stream bank stability, water quality and stream side vegetation.

Aquatic biota would be beneficially affected as a result of diversifying aquatic habitat through modified dredging of arroyos and opening former meanders. A total of 59 acres of backwater habitat would be developed. In addition, modified grazing in the riparian area and bosque development would beneficially effect stream bank stability, water quality and stream side vegetation.

Land Use Land use in the potential area of influence would remain unaffected relative to current conditions.

Beneficial effects are expected from ongoing recreational initiatives.

The RGCP operation and maintenance would not change from the current practices.

Levee rehabilitation would be the only action with potential effects on land use adjacent to the RGCP. Up to 50 acres of the approximately 149 acres of borrow sites would be likely located in agricultural areas. Land use change would not be significant relative to 19,020 acres of farmlands in the area adjacent to the ROW.

Beneficial effects are expected from ongoing recreational initiatives.

Up to 50 acres of agricultural land would be needed as borrow sites. With implementation of an on-farm water conservation program, no other changes in land use are anticipated.

With direct purchase of water rights, environmental measure implementation could result in 734 acres of cropland retirement (0.97% of EBID irrigated acreage).

Beneficial effects are expected from ongoing recreational initiatives.

Conservation easements would affect up to 288 acres of cropland in addition to 50 acres of borrow sites (in combination, 1.8% of farmland adjacent to the ROW. Current use would be maintained for another 1,330 acres of remnant bosques.

With direct purchase of water rights, measure implementation could result in 3,154 acres of cropland retirement (4.7% of EBID irrigated acreage).

ES-10 June 2004

No Action Alternative

Flood Control Improvement Alternative

Integrated USIBWC Land Management Alternative

Targeted River Restoration Alternative

Socioeconomics and Environmental Justice

No change relative to current conditions

Similar to the No Action Alternative, except there would be additional short-term jobs as a result of levee rehabilitation activities.

Similar to the No Action Alternative, with the addition of short-term jobs as a result of an increase in construction activities.

With on-farm conservation, no adverse effects on agricultural communities are anticipated.

For direct water acquisition, the potential annual loss in crop value would be approximately $900,000, and $1.6 million in indirect effects.

Similar to the No Action Alternative, except there would be additional short-term jobs by increase in construction activities.

With on-farm conservation, no adverse effects on agricultural communities are anticipated.

For direct water acquisition, the potential annual loss in crop value would be approximately $4 million, and $7.3 million in indirect effects.

Cultural Resources No change relative to current conditions

The alternative will not adversely affect, any architectural resources, traditional cultural properties or archaeological resources.

Similar to the No Action Alternative, except there would be a potential for undiscovered sites at two locations near shavedown projects.

Similar to the No Action Alternative, except there would be a potential for undiscovered sites at three sites located near arroyo or meander projects.

Air Quality Emissions generating activities would be the same as the current ongoing activities.

Criteria pollutant increases in the Air Quality Control Region (AQCR) would range from 0.05 to 0.93 percent and would not be regionally significant.

Criteria pollutant increases in the AQCR would range from 0.01 to 1.25 percent and would not be regionally significant.

Criteria pollutant increases in the AQCR would range from 0.12 to 1.62 percent and would not be regionally significant.

Noise No change relative to current conditions

No change in noise levels from maintenance and operation activities.

Noise from additional construction activities would be intermittent and short-term in duration.

No change in noise levels from maintenance and operation activities.

Noise from additional construction activities would be intermittent and short-term in duration.

No change in noise levels from maintenance and operation activities.

Noise from additional construction activities would be intermittent and short-term in duration.

Transportation No change relative to current conditions

The existing level of service (LOS ) of all listed roadways would not change from existing conditions.

The LOS of all listed roadways would not change from existing conditions.

The LOS of all listed roadways would not change from existing conditions.

Cumulative Impacts No change relative to current conditions

No change relative to current conditions

A 1% increase in EBID irrigated land conversion above 18% anticipated for the El Paso-Las Cruces Regional Sustainable Water Project.

A 4.2% increase in EBID irrigated land conversion above 18% anticipated for the El Paso-Las Cruces Regional Sustainable Water Project.

Final EIS – River Management Alternatives for the Draft EIS Additions and Modifications Rio Grande Canalization Project (RGCP) Introduction

CHAPTER I

ADDITIONS AND MODIFICATIONS TO THE DRAFT EIS

This chapter contains sections of the Draft EIS that were updated or modified to address reviewer comments, and two sections added to incorporate information following release of the Draft EIS.

Added and modified sections are presented in subchapters A through G, as follows:

Page

I.A Table of Contents: A revised version from the Draft EIS is provided, highlighting additions and modifications included in the Final EIS

I-1

I.B Section 1: A more detailed description of USIBWC authority is provided (Subsection 1.1.3). I-7

I.C Section 2: A new section is included indicating selection of a preferred river management alternative for the RGCP, and the basis for USIBWC’s decision (Section 2.13). The summary comparison of alternatives and effects (2.12) is updated to reflect Section 4 modifications.

I-9

I.D Section 3: An updated section on water quality baseline is provided (Subsection 3.1.3). I-15

I.E Section 4: Updated sections are provided on the summary of potential effects for water resources and land use (Subsections

4.1.2 and 4.8.2, respectively); revised socioeconomic analysis individually by county (Section 4.9); and updated analysis of cumulative effects of regional plans (Subsection 4.15.1).

I-17

I.F Section 5: A new subsection is included documenting the Draft EIS review period, and the January 27, 2004 public hearing (Subsection 5.1.4).

I-33

I.G An errata table is provided with editorial or non-substantial corrections to the Draft EIS text. I-34

Rio Grande Canalization Project (RGCP) Revised Table of Contents

I-1 June 2004

SUBCHAPTER I.A – ADDITIONS AND MODIFICATIONS TO THE DRAFT EIS,

REVISED TABLE OF CONTENTS

Draft EIS sections that were added or modified in the Final EIS are highlighted in the revised Table of Contents below. The replacement text for each section is provided in subchapters I.B through I.G.

SECTION 1 PURPOSE OF AND NEED FOR ACTION 1-1

1.1 PURPOSE OF AND NEED FOR ACTION 1-1

1.1.1 Proposed Action and Need 1-1

1.1.2 Criteria for Alternatives Formulation 1-2

1.1.3 Authority (Text modified in the Final EIS) 1-3

1.2 BACKGROUND 1-3

1.2.1 USIBWC Organization and Mission 1-3

1.2.2 Rio Grande Canalization Project 1-7

1.3 DRAFT EIS PREPARATION 1-8

1.3.1 Memorandum of Understanding 1-8

1.3.2 Agency and Public Participation 1-9

1.3.3 Significant Issues by Resource Category 1-9

1.3.4 Opportunities and Constraints 1-12

1.3.5 Prior Environmental Evaluations and Support Documents 1-14

1.4 AUTHORITY AND INSTITUTIONAL INVOLVEMENT 1-15

1.5 SCOPE OF THE IMPACT ANALYSIS 1-16

1.6 DOCUMENT ORGANIZATION 1-16

SECTION 2 DESCRIPTION OF ALTERNATIVES 2-1

2.1 ALTERNATIVES SUMMARY 2-1

2.2 THE NO ACTION ALTERNATIVE 2-1

2.2.1 Levee System Management 2-2

2.2.2 Floodway Management 2-5

2.2.3 Maintenance of Pilot Channel and Irrigation Facilities 2-6

2.2.4 Sediment Management 2-7

2.3 FLOOD CONTROL IMPROVEMENT ALTERNATIVE 2-8

2.3.1 Levee System Management 2-8

2.3.2 Floodway Management 2-10

2.3.3 Maintenance of Pilot Channel and Irrigation Facilities 2-11

2.3.4 Sediment Management 2-11

2.4 INTEGRATED USIBWC LAND MANAGEMENT ALTERNATIVE 2-11

2.4.1 Levee System Management 2-12

2.4.2 Floodway Management 2-12

2.4.3 Maintenance of Pilot Channel and Irrigation Facilities 2-17

2.4.4 Sediment Management 2-17

2.5 TARGETED RIVER RESTORATION ALTERNATIVE 2-17

2.5.1 Levee System Management 2-18

2.5.2 Floodway Management 2-18

2.5.3 Maintenance of Pilot Channel and Irrigation Facilities 2-19

2.5.4 Sediment Management 2-20

2.6 PROJECTS ASSOCIATED WITH THE ALTERNATIVE 2-23

2.6.1 Linear Projects 2-23

2.6.2 Point Projects 2-24

2.6.3 Summary of Projects 2-26

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2.7 ALTERNATIVES CONSIDERED BUT NOT CARRIED FORWARD 2-35

2.7.1 RGCP Partial Decommissioning Alternative 2-35

2.7.2 Multipurpose Watershed Management Alternative 2-35

2.7.3 Restoration Alternative Based on Non-Structural Flood Control 2-36

2.8 PROJECTS AND ACTIONS WITH POTENTIAL CUMULATIVE EFFECTS 2-39

2.8.1 Regional Water Management Plans 2-39

2.8.2 Analysis of Structural Condition of the Levees 2-39

2.9 IMPLEMENTATION STRATEGY 2-40

2.9.1 Program Management 2-40

2.9.2 Water Acquisition 2-41

2.9.3 Cooperation Agreements 2-43

2.10 IMPLEMENTATION TIMETABLE 2-44

2.10.1 Linear Projects 2-45

2.10.2 Point Projects 2-46

2.11 CAPITAL COST EVALUATION 2-47

2.11.1 Flood Control Improvements 2-48

2.11.2 Environmental Measure Implementation 2-48

2.11.3 Water Acquisition 2-48

2.12 SUMMARY COMPARISON OF ALTERNATIVES AND EFFECTS

(Text Updated to Reflect Changes in Sections 4.1, 4.8, 4.9 and 4.15) 2-48

2.13 PREFERRED ALTERNATIVE (Section Added to the Final EIS) 2-53

SECTION 3 AFFECTED ENVIRONMENT 3-1

3.1 WATER RESOURCES 3-1

3.1.1 Water Consumption 3-1

3.1.2 Water Delivery 3-6

3.1.3 Water Quality (Text Updated in the Final EIS) 3-9

3.2 FLOOD CONTROL 3-11

3.2.1 Existing Flood Control 3-11

3.2.2 Flood Containment Capacity Evaluation 3-12

3.3 SOILS 3-15

3.3.1 Soil Characterization 3-15

3.3.2 Soil Distribution within the RGCP 3-17

3.3.3 Soil Erosion 3-17

3.4 VEGETATION AND WETLANDS 3-19

3.4.1 Ecological Region 3-19

3.4.2 Riparian Communities 3-19

3.4.3 Vegetation Communities Descriptions 3-24

3.4.4 Invasive Species 3-27

3.4.5 Vegetation Management within the ROW 3-28

3.5 WILDLIFE HABITAT 3-31

3.5.1 Quantification of Habitat Value 3-31

3.6 ENDANGERED AND OTHER SPECIAL STATUS WILDLIFE SPECIES 3-33

3.6.1 Threatened and Endangered Species 3-33

3.6.2 Species of Concern 3-33

3.7 AQUATIC BIOTA 3-37

3.7.1 Habitat Characterization 3-37

3.7.2 Habitat Suitability 3-37

3.7.3 Fish Species Composition 3-41

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3.8 LAND USE 3-43

3.8.1 Land Use Analysis 3-43

3.8.2 Land Use Corridor 3-44

3.8.3 Recreational Use 3-45

3.9 SOCIOECONOMICS AND ENVIRONMENTAL JUSTICE 3-52

3.9.1 Socioeconomic Criteria 3-52

3.9.2 Environmental Justice 3-56

3.10 CULTURAL RESOURCES 3-58

3.10.1 Architectural Resources 3-58

3.10.2 Traditional Cultural Properties 3-60

3.10.3 Archaeological Resources 3-60

3.10.4 Summary of Findings 3-63

3.11 AIR QUALITY 3-64

3.11.1 Air Pollutants and Regulations 3-64

3.11.2 Regional Air Quality 3-67

3.11.3 Baseline Air Emissions 3-67

3.12 NOISE 3-69

3.12.1 Guidelines 3-69

3.12.2 Baseline Noise Levels 3-70

3.13 TRANSPORTATION 3-71

SECTION 4 ENVIRONMENTAL CONSEQUENCES 4-1

4.1 WATER RESOURCES 4-2

4.1.1 Method of Analysis 4-2

4.1.2 Summary of Potential Effects (Text Modified in the Final EIS) 4-2

4.1.3 No Action Alternative 4-2

4.1.4 Flood Control Improvement Alternative 4-4

4.1.5 Integrated USIBWC Land Management Alternative 4-4

4.1.6 Targeted River Restoration Alternative 4-5

4.2 FLOOD CONTROL 4-7

4.2.1 Method of Analysis 4-7

4.2.2 Summary of Effects 4-8

4.2.3 No Action Alternative 4-9

4.2.4 Flood Control Improvement Alternative 4-9

4.2.5 Integrated USIBWC Land Management Alternative 4-9

4.2.6 Targeted River Restoration Alternative 4-10

4.3 SOILS 4-11

4.3.1 Method of Analysis 4-11

4.3.2 Summary of Potential Effects 4-14

4.3.3 No Action Alternative 4-14

4.3.4 Flood Control Improvement Alternative 4-14

4.3.5 Integrated USIBWC Land Management Alternative 4-16

4.3.6 Targeted River Restoration 4-17

4.4 VEGETATION AND WETLANDS 4-18

4.4.1 Method of Analysis 4-18

4.4.2 Summary of Potential Effects 4-23

4.4.3 No Action Alternative 4-23

4.4.4 Flood Control Improvement Alternative 4-25

4.4.5 Integrated USIBWC Land Management Alternative 4-27

4.4.6 Targeted River Restoration Alternative 4-29

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4.5 WILDLIFE HABITAT 4-32

4.5.1 Method of Analysis 4-32

4.5.2 Summary of Effects 4-35

4.5.3 No Action Alternative 4-35

4.5.4 Flood Control Improvement 4-36

4.5.5 Integrated USIBWC Land Management Alternative 4-37

4.5.6 Targeted River Restoration Alternative 4-38

4.6 ENDANGERED AND THREATENED SPECIES OF CONCERN 4-40

4.6.1 Method of Analysis 4-40

4.6.2 Summary of Potential Effects 4-42

4.6.3 No Action Alternative 4-43

4.6.4 Flood Control Improvement Alternative 4-43

4.6.5 Integrated USIBWC Land Management Alternative 4-44

4.6.6 Targeted River Restoration Alternative 4-45

4.7 AQUATIC BIOTA 4-46

4.7.1 Method of Analysis 4-46

4.7.2 Summary of Potential Effects 4-47

4.7.3 No Action Alternative 4-48

4.7.4 Flood Control Improvement Alternative 4-48

4.7.5 Integrated USIBWC Land Management Alternative 4-48

4.7.6 Targeted River Restoration Alternative 4-48

4.8 LAND USE 4-49

4.8.1 Method of Analysis 4-49

4.8.2 Summary of Potential Effects (Text Modified in the Final EIS) 4-50

4.8.3 No Action Alternative 4-50

4.8.4 Flood Control Improvement Alternative 4-51

4.8.5 Integrated USIBWC Land Management Alternative 4-51

4.8.6 Targeted River Restoration Alternative 4-52

4.9 SOCIOECONOMIC RESOURCES AND ENVIRONMENTAL JUSTICE 4-52

4.9.1 Method of Analysis (Text Modified in the Final EIS) 4-53

4.9.2 Summary of Potential Effects (Analysis by Individual County) 4-54

4.9.3 No Action Alternative 4-56

4.9.4 Flood Control Improvement Alternative 4-56

4.9.5 Integrated USIBWC Land Management Alternative 4-57

4.9.6 Targeted River Restoration Alternative 4-58

4.10 CULTURAL RESOURCES 4-59

4.10.1 Method of Analysis 4-60

4.10.2 Summary of Potential Effects 4-61

4.10.3 No Action Alternative 4-61

4.10.4 Flood Control Improvement Alternative 4-62

4.10.5 Integrated USIBWC Land Management 4-62

4.10.6 Targeted River Restoration 4-63

4.11 AIR QUALITY 4-65

4.11.1 Method of Analysis 4-65

4.11.2 Summary of Potential Effects 4-67

4.11.3 No Action Alternative 4-67

4.11.4 Flood Control Improvement Alternative 4-68

4.11.5 Integrated USIBWC Land Management Alternative 4-71

4.11.6 Targeted River Restoration Alternative 4-72

4.12 NOISE 4-73

4.12.1 Method of Analysis 4-73

4.12.2 Summary of Potential Effects 4-74

4.12.3 No Action Alternative 4-74

4.12.4 Flood Control Improvement Alternative 4-75

4.12.5 Integrated USIBWC Land Management Alternative 4-75

4.12.6 Targeted River Restoration Alternative 4-76

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4.13 TRANSPORTATION 4-76

4.13.1 Method of Analysis 4-76

4.13.2 Summary of Potential Effects 4-77

4.13.3 No Action Alternative 4-77

4.13.4 Flood Control Improvement Alternative 4-77

4.13.5 Integrated USIBWC Land Management Alternative 4-79

4.13.6 Targeted River Restoration Alternative 4-79

4.14 MITIGATION MEASURES 4-80

4.14.1 Water Resources 4-81

4.14.2 Flood Control and Soil Excavation 4-82

4.14.3 Biological Resources 4-82

4.14.4 Land Use, Socioeconomics and Cultural Resources 4-84

4.14.5 Air, Noise and Transportation 4-84

4.15 CUMULATIVE EFFECTS 4-85

4.15.1 Regional Plans (Text Updated in the Final EIS) 4-86

4.15.2 Analysis of Structural Condition of the Levees 4-86

4.16 UNAVOIDABLE ADVERSE IMPACTS 4-87

4.17 RELATIONSHIP BETWEEN THE SHORT-TERM USE OF THE

ENVIRONMENT AND LONG-TERM PRODUCTIVITY 4-87

4.18 IRREVERSIBLE AND IRRETRIEVABLE COMMITMENT OF RESOURCES 4-88

SECTION 5 CONSULTATION AND COORDINATION 5-1

5.1 DRAFT EIS PREPARATION OVERVIEW 5-1

5.1.1 Public Scoping Meetings 5-1

5.1.2 Consultation for Formulation of Alternatives 5-2

5.1.3 Reformulation of Alternatives 5-3

5.1.4 Draft EIS Public Review Period (Subsection Added to the Final EIS) 5-11

5.2 LIST OF CONTRIBUTORS 5-6

5.3 DISTRIBUTION LIST 5-8

SECTION 6 GLOSSARY AND REFERENCES 6-1

6.1 GLOSSARY 6-1

6.2 REFERENCES 6-17

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APPENDICES:

Appendix A River Management Unit Description

Appendix B Flood Control Improvement Project Summary (USACE 1996)

Appendix C Aquatic Habitat Evaluation

Appendix D Scientific Name List

Appendix E Flood Containment Capacity Analysis

Appendix F Controlled Water Releases for Overbank Flows

Appendix G Preliminary Cost Estimates for the Alternatives

Appendix H Comments to the Reformulation Report and USIBWC Responses

Appendix I Reformulation of Alternatives Report (CD format)

Appendix J Cross-referencing index of comments and responses (New Final EIS Appendix)

Appendix K Correspondence on Draft EIS (New Final EIS Appendix)

Appendix L Public Hearing Transcript (New Final EIS Appendix)

Appendix M Additional Cultural Resources Consultation (New Final EIS Appendix)

Appendix N Socioeconomic Effects Analysis Support Documentation (New Final EIS Appendix)

Appendix O Acts of Congress Authorizing USIBWC to Construct, Operate and Maintain the RGCP (New Final EIS Appendix)

Appendix P USFWS Letter of Concurrence with Findings of the RGCP Biological Assessment (New Final EIS Appendix)

Appendix Q Final EIS and Technical Support Documents (New Final EIS Appendix, in CD Format)

Rio Grande Canalization Project (RGCP) Section 1: Purpose Of and Need For Action

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SUBCHAPTER I.B – ADDITIONS AND MODIFICATIONS TO SECTION 1,

PURPOSE OF AND NEED FOR ACTION

An expanded version was prepared on the USIBWC’s authority for consideration of environmental improvements in the RGCP, and the agency’s operational procedures for NEPA compliance (Subsection 1.1.3, page 1-3 of the Draft EIS).

1.1 NEED FOR ACTION

1.1.3 Authority

The USIBWC is the lead federal agency for preparation of this Environmental

Impact Statement (EIS). The United States Bureau of Reclamation (USBR, Albuquerque Area Office, New Mexico) is a cooperating agency.

Compliance with the National Environmental Policy Act

Changes under consideration for RGCP operation and maintenance (O&M) and implementation of environmental measures constitute a major federal action requiring preparation of an EIS as stipulated by:

• The National Environmental Policy Act (NEPA) of 1969, as amended (Pub. L.

91-190, 42 U.S.C. 4321-4347, January 1, 1970, as amended by Pub. L. 94-52, July 3, 1975, and Pub. L. 94-83, August 9, 1975);

• The Council on Environmental Quality (CEQ), Executive Office of the President, Regulations for Implementing the Procedural Provisions of NEPA (40 CFR 1500- 1508); and

• The USIBWC Operational Procedures for Implementing Section 102 of NEPA as published in the Federal Register on September 2, 1981 (Federal Register 46, No. 170: 44083-44094). These procedures identify actions that constitute categorical exclusions.

Authority to Accomplish Flood Control, Water Delivery, and Operation and Maintenance Activities In A Manner That Enhances Or Restores the Riparian Ecosystem

The USIBWC has the authority and responsibility to evaluate river management alternatives for future operations and maintenance of the RGCP to enhance ecosystem restoration while accomplishing its flood control and water delivery mission. The authority to construct, operate and maintain works for the canalization of the Rio Grande also includes a responsibility to consider environmental improvements in the project area.

An Act…