Review of the
Edwards Aquifer Habitat
Committee to Review the Edwards Aquifer Habitat Conservation Plan
Water Science and Technology Board
Division on Earth and Life Studies
A Report of
THE NATIONAL ACADEMIES PRESS
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This activity was supported by the Edwards Aquifer Authority under Contract No. 13-666-HCP. Any opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of any organization or agency that provided support for the project.
International Standard Book Number-13: 978-0-309-45155-0
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Digital Object Identifier: 10.17226/23685
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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2017. Review of the Edwards Aquifer Habitat Conservation Plan: Report 2. Washington, DC: The National Academies Press. doi: 10.17226/23685.
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COMMITTEE TO REVIEW THE EDWARDS AQUIFER HABITAT CONSERVATION PLAN PHASE 2
DANNY D. REIBLE, Chair, Texas Tech University, Lubbock
JONATHAN D. ARTHUR, Florida Department of Environmental Protection, Tallahassee
M. ERIC BENBOW, Michigan State University, East Lansing
ROBIN K. CRAIG, University of Utah, Salt Lake City
K. DAVID HAMBRIGHT, University of Oklahoma, Norman
LORA A. HARRIS, University of Maryland Center for Environmental Science, Solomons
TIMOTHY K. KRATZ, University of Wisconsin, Madison
ANDREW J. LONG, U.S. Geological Survey, Rapid City, South Dakota
JAYANTHA OBEYSEKERA, South Florida Water Management District, West Palm Beach
KENNETH A. ROSE, Louisiana State University, Baton Rouge
LAURA TORAN, Temple University, Philadelphia, Pennsylvania
GREG D. WOODSIDE, Orange County Water District, Fountain Valley, California
National Academies Staff
LAURA J. EHLERS, Study Director, Water Science and Technology Board
BRENDAN McGOVERN, Senior Program Assistant, Water Science and Technology Board
WATER SCIENCE AND TECHNOLOGY BOARD
GEORGE M. HORNBERGER, Chair, Vanderbilt University, Nashville, Tennessee
EDWARD J. BOUWER, Johns Hopkins University, Baltimore, Maryland
DAVID A. DZOMBAK, Carnegie Mellon University, Pittsburgh, Pennsylvania
M. SIOBHAN FENNESSY, Kenyon College, Gambier, Ohio
BEN GRUMBLES, Maryland Department of the Environment, Baltimore, Maryland
ARTURO A. KELLER, University of California, Santa Barbara
CATHERINE L. KLING, Iowa State University, Ames
LARRY LARSON, Association of State Floodplain Managers, Madison, Wisconsin
DINAH LOUDA, Veolia Institute, Paris, France
STEPHEN POLASKY, University of Minnesota, St. Paul
JAMES W. ZIGLAR, SR., Van Ness Feldman, Potomac, Maryland
ELIZABETH EIDE, Acting Director
LAURA J. EHLERS, Senior Staff Officer
STEPHANIE E. JOHNSON, Senior Staff Officer
ED DUNNE, Staff Officer
M. JEANNE AQUILINO, Financial/Administrative Associate
BRENDAN R. McGOVERN, Senior Project Assistant
The Edwards Aquifer in south-central Texas is an important drinking water resource but also provides critical habitat for threatened and endangered species that inhabit the freshwater that forms the San Marcos and Comal Rivers. The unique habitat afforded by these spring-fed rivers has led to the evolution of species that are found in no other locations on Earth. Because of the potential for variations in spring flow due to both human and natural causes, the Edwards Aquifer Authority (EAA) and stakeholders have developed a Habitat Conservation Plan (HCP) to protect these unique threatened and endangered species. The HCP seeks to effectively manage the river-aquifer system to ensure the viability of the endangered species in the face of future water quantity concerns, such as drought and increased demand from population growth, as well as water quality threats to the aquifer.
The National Academies of Sciences, Engineering, and Medicine were asked by the EAA to assist in this process by forming a committee of expert volunteers that could review the implementation of HCP activities. The National Academies’ study was planned in three phases, with the first phase being a review of the scientific efforts conducted to help build a better understanding of the river-aquifer system and its relationship to the endangered species, including monitoring and modeling. The first phase led to a report published in 2015 that provided an evaluation and recommendations for strengthening those efforts.
The current report is the culmination of the second phase. This report reviews the progress in implementing the recommendations from the Committee’s first report, seeking to clarify and provide additional support
for implementation efforts where appropriate. The current report also reviews selected Applied Research projects and minimization and mitigation (M&M) measures to help ensure their effectiveness in meeting the goals of the HCP. This report does not evaluate the adequacy of the goals and objectives of the HCP to protect the endangered species nor the capability of the M&M measures to meet those goals. These topics are expected to be part of the third and final report.
A committee was established under the auspices of the Water Science and Technology Board (WSTB) of the National Academies with the title Committee to Review the Edwards Aquifer Habitat Conservation Program. The Committee included 12 individuals representing expertise in all areas relevant to the Statement of Task, including the hydrogeology of the aquifer and the physics, chemistry, and biology of river systems. Four meetings were held over the past year since the release of the Committee’s first report. The first two meetings were held in San Antonio and included presentations on current EAA and HCP activities relevant to the Statement of Task. I would like to thank the following individuals for giving presentations to the Committee during one or more of its meetings: Nathan Pence, Executive Director of the Habitat Conservation Program, EAA; Alicia Reinmund-Martinez, EAA; Jared Morris, EAA; Jim Winterlee, EAA; Mark Hamilton, EAA; Ed Oborny, BIO-WEST; Tim Osting, AquaStrategies; Mark Enders, the City of New Braunfels; George Ward, University of Texas; Bill Grant and Rose Wang, University of Texas; Todd Swannack, Engineer Research and Development Center; and Thom Hardy, Texas State University. I would also like to thank the many people who helped organize and run the three field trips taken by the Committee, particularly Nathan Pence, EAA; Ed Oborny, BIO-WEST; Zac Martin, City of New Braunfels; Melani Howard, City of San Marcos; and Steve Bereyso, SAWS.
Although Committee members represented many diverse perspectives and areas of expertise, which varied from river-aquifer hydrology to biology, we reached consensus on all recommendations included in the report. We hope that the EAA will find these recommendations useful as they guide the scientific initiatives designed to provide a solid foundation for effective management of the river-aquifer system and protection of the endangered species.
This report has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise. The purpose of this independent review is to provide candid and critical comments that will assist the institution in making its published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their review of this report:
James J. Anderson, University of Washington, Seattle
John D. Bredehoeft, NAE, The Hydrodynamics Group, LLC., Sausalito, CA
Stephen R. Carpenter, NAS, University of Wisconsin, Madison
Wendy D. Graham, University of Florida Water Institute, Gainesville
Jessie C. Jarvis, University of North Carolina, Wilmington
Keith P. Johnston, NAE, University of Texas, Austin
Stavros S. Papadopulos, NAE, S.S. Papadopulos & Associates, Inc. Bethesda, MD
Steven F. Railsback, Lang Railsback & Associates, Arcata, CA
Although the reviewers listed above have provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations nor did they see the final draft of the report before its release. The review of this report was overseen by Patrick L. Brezonik, University of Minnesota, Minneapolis; and R. Rhodes Trussell, Trussell Technologies, Inc., who were responsible for making certain that an independent examination of this report was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content of this report rests entirely with the authoring Committee and the institution.
Danny D. Reible, Chair
Committee to Review the Edwards Aquifer
Habitat Conservation Plan
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