STATEMENT OF

DR. P. PATRICK LEAHY

U.S. GEOLOGICAL SURVEY

U.S. DEPARTMENT OF THE INTERIOR

BEFORE THE

COMMITTEE ON RESOURCES

SUBCOMMITTEE ON WATER AND POWER

U.S. HOUSE OF REPRESENTATIVES

ON

S.214/H.R. 469, "UNITED STATES-MEXICO TRANSBOUNDARY AQUIFER ASSESSMENT
ACT"

May 10, 2006

Mr. Chairman and Members of the Subcommittee, thank you for the
opportunity to participate in this hearing to discuss the important role
of water in the U.S.-Mexico Border Region and to provide the
Administration\'s views on S.214 and H.R. 469, the \"United
States-Mexico Transboundary Aquifer Assessment Act.\" The Administration
supports the provisions of S.214/H.R. 469, however, we note that we
currently are undertaking some work in the areas covered by the bills
and that no new authorities are needed. The program authorized in these
bills would need to compete among the Administration's other priorities
for funding.

**Background**

The international border region of the United States and Mexico (border
region) has, during the past decade, experienced significant economic
expansion accompanied by rapid population growth and urban development.
The removal of international trade barriers quickly transformed the
region\'s several small to mid-size cities into some of the fastest
growing population centers in both countries. As a result, the people
residing on both sides of the border now face numerous complex social,
political, economic, infrastructure, public health, natural resource,
and environmental-quality challenges. Along the entire length of the
mostly arid international border region, perhaps the greatest challenge
is how to effectively address the need for safe, sustainable supplies of
good quality water for public, industrial, and agricultural uses, while
maintaining a delicate balance with the needs of a very fragile
natural-resource system.

The limited surface-water supplies along the border have been allocated
for several decades under international treaties and domestic laws.
However, allocation of ground water in the border region is poorly
regulated because little is known about its availability,
sustainability, and quality; about how ground water interacts with
surface-water bodies; and about the susceptibility of ground water to
contamination. Ground water also is an important source of
life-sustaining base flow to many streams and essential for maintaining
critical aquatic habitats.

Ground-water pumping has lowered the water table, depleted aquifers, and
reduced the base flow of many streams, thus decreasing the quantity of
water available to people and critical riparian habitats. Excessive
ground-water pumping in some major urban centers, such as in the El
Paso/Juarez metropolitan region, has caused land subsidence that has
damaged homes and essential urban infrastructure. In addition to the
effects of ground- and surface-water depletion, degradation of water
quality has reduced habitat suitability for the region\'s diverse biota.
The problems associated with limited water quantity and competing uses
of water also have resulted in impaired and degraded water quality and
serious issues related to human health on both sides of the border.
Water quantity and quality will most likely be the determining and
limiting factors that ultimately control future economic development,
population growth, and human health along the United States-Mexico
border.

**S.214/H.R. 469**

S.214 and H.R. 469 direct the Secretary of the Interior to establish a
United States-Mexico Transboundary Aquifer Assessment Program to
systematically assess priority transboundary aquifers and provide the
scientific foundation necessary for State and local officials to address
pressing water resource challenges in the border region. The bills
further direct the Secretary of the Interior to implement this program
in cooperation with the Border States as well as with other appropriate
entities, including affected Indian tribes.

The proposed, collaborative scientific investigations and research
efforts would address critical water supply, environmental, and
natural-resource issues in the border region, and contribute to an
improved understanding of the relations between the border region\'s
many water, natural-resource, biological, and human-health related
issues. Additionally, these studies would develop and document the
tools, scientific methodologies, and procedures for collecting and
integrating hydrologic, geologic, biologic, and other spatial data into
a binational geographic information system for analysis and modeling
applications. We agree that a multi-discipline, binational, scientific
approach is needed to address these complex, interrelated transboundary
issues. Accordingly, the USGS Border Environmental Health Initiative,
now in its third year, has developed a framework for a borderwide
integrated binational database for water quality and quantity
information.

The objectives of S.214 and H.R. 469 include expanding existing
agreements between the USGS, Border States, State Water Resources
Research Institutes, and appropriate authorities in the United States
and Mexico to conduct joint investigations; document, manage, and share
data; and carry out the necessary binational work efforts. Such
collaboration would produce timely, widely accepted scientific products
and understanding of each priority binational aquifer that is needed by
water and natural-resource managers to effectively accomplish their
missions.

The role identified for the Department of the Interior in these bills is
consistent with the USGS leadership role in monitoring, interpretation,
research, and assessment of the health and status of the water and
biological resources of the Nation. As the Nation\'s largest water,
earth, and biological science, and civilian mapping agency, the USGS
provides the largest single non-regulatory hydrologic investigative and
research capability in the Nation.

This proposed scientific collaboration by Federal, State, Tribal, and
academic institutions touches on many of the interdisciplinary core
competencies of the USGS. For example, current efforts, such as working
with Mexico and Canada on the North America Atlas to develop
standardized fundamental geospatial data layers, and with Mexican
federal agencies (INEGI - Instituto Nacional de Estadística, Geografía e
Informática; IMTA - Instituto Mexicano de Tecnología del Agua; and CNA -
Comisión Nacional del Agua) to develop standardized approaches for
delineating watersheds and defining hydrologic characteristics, are
currently being implemented in this region and others. At its heart,
such collaboration effectively capitalizes on the collective scientific
capability and resources of the partnering institutions. The integration
of this relevant science addresses pressing and complex natural resource
and environmental problems in these very fragile landscapes and complex
ecosystems.

The USGS has been active in a number of relevant programs and
investigations in the arid southwest and, hence, has a working knowledge
of proven methods and innovative technologies for effectively
characterizing, monitoring, and mapping the border region\'s
ground-water resources. We believe we have the authority to implement
the activities called for in these identical bills and would continue to
provide resources to address the goals of S.214 and H.R. 469, provided
these activities successfully compete against other USGS priorities.

USGS scientists working from offices in each of the four Border States
actively participate in ongoing programs and investigations, and are
called upon by the States and border communities to provide essential
technical insight and understanding for solving critical water-supply
and natural-resource problems. Our scientists serve on a large number of
relevant committees, task forces, and advisory groups in the border
region. Regional coordination and communication of USGS programs and
activities along the international border is further enhanced internally
through our Borderlands Workgroup, as well as within the Department of
the Interior as a result of our active participation on the U.S.-Mexico
Field Coordination Committee.

Talking with our partners in the Border States and communities, in the
other Interior Bureaus, and other Federal agencies, as well with
scientists and government officials in Mexico, it is widely acknowledged
that the lack of a standardized, binational database on the
availability, use, and quality of transboundary ground-water resources
is perhaps the most significant impediment in addressing the Border
region\'s numerous complex water-supply and natural-resource challenges.
The lack of basic inventory and monitoring information pertaining to
border water resources and water-dependent environments prevents a
comprehensive understanding of watershed and regional processes and
issues, and hinders the ability of science to provide the essential
predictive capability to characterize or describe potential cause and
effect relations associated with alternative land and water use and
management actions.

The program and investigations called for in these bills would support
the development and maintenance of such a standardized, binational
hydrologic database and associated data analysis tools. Early into the
program, it would be essential that binational consensus be reached on
common investigative approaches, common field data collection protocols,
laboratory methodologies, and data management, documentation, and
reporting systems. Once these technical issues are resolved, it would be
much easier to streamline the binational requirements related to the
review and public release of impartial, transboundary scientific data.
Such consensus has been reached in the past for transboundary
investigations having limited scope. Obtaining this consensus for the
entire Border region would greatly enhance transboundary scientific
collaboration in the future.

**Summary**

The proposed investigations and pertinent research efforts authorized by
S. 214 and H.R. 469 would address critical water, environmental, and
health issues in the Border region and contribute to a more
comprehensive understanding of the relations between the region\'s many
water, natural-resource, biological, and health-related issues. It is
important that a bi-national, multi-discipline scientific approach be
taken to address these interrelated issues. Additionally, these
binational studies would develop and document the tools, methodologies,
and procedures to collect and integrate hydrologic, biologic, and other
spatial data into the USGS Border Environmental Health Initiative
geographic information system for analysis and modeling applications.

Thank you, Mr. Chairman, for the opportunity to present this testimony.
I will be pleased to answer questions you and other Members of the
Subcommittee might have.