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Haven Or Hazard: the Ecology and Future of the Salton Sea

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Haven Or Hazard: the Ecology and Future of the Salton Sea Haven or Hazard: The Ecology and Future of the Salton Sea Michael J. Cohen Jason I. Morrison Edward P. Glenn A report of the PACIFIC INSTITUTE FOR STUDIES IN DEVELOPMENT, ENVIRONMENT, AND SECURITY February 1999 Prepared with the support of the U.S. Environmental Protection Agency, Region IX The Compton Foundation The Turner Foundation and the Oracle Corporate Giving Program Haven or Hazard: The Ecology and Future of the Salton Sea © Copyright 1999 by the Pacific Institute for Studies in Development, Environment, and Security All Rights Reserved Pacific Institute for Studies in Development, Environment, and Security 654 13th Street Preservation Park Oakland, California 94612 www.pacinst.org (510) 251-1600 (telephone) (510) 251-2203 (fax) Printed on 100-percent recycled paper About the Pacific Institute The Pacific Institute for Studies in Development, Environment, and Security is an inde- pendent, non-profit center created in 1987 to do research and policy analysis in the areas of environment, sustainable development, and international security. Underlying all of the Insti- tute’s work is the recognition that the pressing problems of environmental degradation, region- al and global poverty, and political tension and conflict are fundamentally interrelated, and that long-term solutions must consider these problems in an interdisciplinary manner. The Institute’s mission is to conduct and distribute meaningful and usable research and policy sug- gestions on the interactions among these issues. The organization seeks to produce quality, impartial research and to make sure it is accessible not only to public and private-sector deci- sion-makers, but also to community groups and the public at large. The ultimate objective of the Pacific Institute’s work is to contribute to equitable and sound development, the reversal of environmental degradation, and regional and international peace and security. About the Authors Michael Cohen is a Research Associate of the Pacific Institute. He holds a Master’s degree in Geography, with a concentration in Resources and Environmental Quality, from San Diego State University. His graduate studies focused on the impacts of institutions on the environ- ment, especially water use in the West. He received a B.A. in Government from Cornell Uni- versity, and served as a Peace Corps Volunteer in Guatemala, prior to working as a Legislative Assistant on Capitol Hill. His current research focuses on the sustainable management of freshwater resources and water planning in the southwestern U.S. and the Colorado River bor- der region. Jason Morrison is a Senior Associate of the Pacific Institute. He holds a Master’s Degree from Boston University’s Center for Energy and Environmental Studies and a B.A. in Philosophy from the University of California, San Diego. In 1994, Mr. Morrison was a fellow with the Amer- icans and World Affairs Fellowship Program in Berkeley, California. Mr. Morrison has published widely in scholarly and popular publications, and is the lead author of a United Nations-funded report entitled The Sustainable Use of Water in the Lower Colorado River Basin. In addition to working on issues relating to western water policy, he heads the Pacific Institute’s Economic Globalization and the Environment Program, where he is currently studying the public policy implications of the international environmental management standards − ISO 14000. Professor Edward P. Glenn is an environmental biologist in the Department of Soil, Water and Environmental Science at the University of Arizona. Since 1991, he has worked with Mexican and other United States scientists on studies of the ecology of the Colorado River delta and upper Gulf of California marine zone. The focus of their research has been to define the water needs of the remaining riparian and wetland habitats of the delta region and develop restora- tion strategies for the delta, using waste flows of water from the United States and Mexico. Their research has been published in Conservation Biology, Ecological Engineering, Aquatic Botany, Southwestern Naturalist and other scientific journals. Special thanks to Dale Pontius, who worked as a consultant on the project. Mr. Pontius is an attorney and consultant specializing in western water, natural resources, and endangered species law and policy. Most recently, he completed a report on the critical issues in the Colorado River iii Haven or Hazard: The Ecology and Future of the Salton Sea basin for the Western Water Policy Review Advisory Commission. From 1992 to 1995, he was Vice President for Conservation Programs and Southwest Director for American Rivers, a national con- servation organization. He served as Executive Assistant to Governor Bruce Babbitt of Arizona from 1978 to 1980, where he was involved in the development and enactment of the Arizona Groundwater Management Act. Mr. Pontius received his law degree from the University of Ari- zona and his B.A. and M.A. in Political Science from Indiana University. Acknowledgments This report of the Pacific Institute for Studies in Development, Environment, and Security is the result of a yearlong effort on the part of many people. Funding for this report was provided by the U.S. Environmental Protection Agency, Region IX, the Compton and Turner Founda- tions, and the Oracle Corporate Giving Program. We gratefully acknowledge their support. Valuable comments on an earlier draft were provided through formal reviews by Daniel Ander- son, Fred Cagle, Eric Connally, David Czamanske, William deBuys, Milton Friend, Tom Kirk, Tsui Meidou, Karen O’Haire, and Jim Setmire. Any errors are our own. Also, special thanks to Milt Friend, Jim Setmire, and Ken Sturm for the use of their photographs. We also would like to thank the following people for their wide range of advice, criticisms, guid- ance, and help: James Abbott, Tina Anderholt, Jose Angel, Sherry Barrett, Mary Belardo, Patricia Brenner, Summer Bundy, Wil Burns, Caitha Calvello, Les Canterbury, Beth Chalecki, Bart Christensen, Brian Cohen, Joan Dainer, Colleen Dwyer, Kevin Fitzsimmons, Daniel Frink, Melinda Gaddis, Peter Gleick, Mary Henry, David Hogan, Stuart Hurlbert, Chris Igbinedion, George Kourous, Patti Kroen, Wendy Laird-Benner, Libby Lucas, Cheryl Mason, Eugenia McNaughton, Doug Mende, Sandra Menke, Lorelei Muenster, Nadine Mupas, Bud Robbins, David Shaari, William Steele, Ken Sturm, Merlin Tostrud, Don Treasure, Carlos Valdes, Linda Vida-Sunnen, Peter Vin- cent, and Arlene Wong. Graphic design: Pope Graphic Arts Center, Berkeley, California Printer and bindery: Alonzo Printing Co., Inc., Hayward, CA, using recycled paper and soy based inks. Cover image: The Salton Basin, showing the Coachella, Imperial, and Mexicali valleys. The city of Mexicali is visible as a gray-blue area in the lower central portion of the image, with a distinct upper boundary marking the U.S.-Mexico border. In this false color composite image, green vegetation appears red. The North American Landscape Characterization (NALC) image was obtained from the Earth Resources Observa- tion Systems (EROS) Data Center Distributed Active Archive Center (EDC DAAC), located in Sioux Falls, South Dakota. This Landsat 4 Multispectral Scanner (MSS) Satellite image was acquired on June 30, 1992 (Path 39 Row 37). The NALC MSS data were resampled to 60-meter pixels in a UTM projection. EDC DAAC' s Home Page provides detailed technical and ordering information about each data set distributed. The URL address is: http://edcwww.cr.usgs.gov/landdaac Special thanks to Aljean Klaassen for helping to obtain this image. iv Executive Overview Haven or Hazard: The Ecology and Future of the Salton Sea Executive Overview he Salton Sea, the largest inland body of water in the state of California, lies 35 miles north of the U.S.-Mexico border in one of the most arid regions in North America. With Ta surface elevation approximately 227 feet below that of the ocean, the Salton Sea is a study in contrasts: it is an agricultural drainage repository that provides vital habitat for more than 380 species of birds, a lake twenty-five percent saltier than the ocean yet teeming with fish, a productive ecosystem marred by frequent fish and bird die-offs. These contrasts reflect the variety of agricultural, ecological, and recreational values provided by the Salton Sea and are emblematic of the challenges faced by those attempting to preserve and enhance them. The objective of this study is to assess and offer guidance on the complex challenges con- fronting the Salton Sea and the current efforts to restore it. From a public interest perspective, we evaluate the federal/state strategy for restoring the Salton Sea and propose an alternative, long-term framework for preserving and enhancing the regional ecosystem. The Salton Sea can only be understood in the context of its physical attributes and the human activities in its watershed. The development of large-scale irrigation projects in the Imperial and Coachella valleys has changed the face of the Salton basin, transforming a desert into a productive agricultural region. Today, approximately 1.35 million acre-feet 1(maf) of water enters the Sea annually, more than 75 percent of which is U.S. agricultural drainage. The quantity of this agricultural drainage sustains the Sea, yet the quality of drainage is responsible for many of the Sea’s problems. The Salton Sea is a terminal lake - the only outflow for its waters is through evaporation. As water evaporates, salts, selenium, and other contaminants are concentrated in the Sea and its sediments. Since 1992, hundreds of thousands of birds have died at the Salton Sea. In the first four months of 1998 alone, 17,000 birds at the Sea, representing 70 species, died from a variety of diseases. Deteriorating ecological conditions have generated concern about the continued via- bility of the Sea as a stopover for migratory birds on the Pacific Flyway. Massive fish die-offs, linked to eutrophic conditions at the Sea, are also a frequent occurrence. The Salton Sea is also becoming increasingly saline, jeopardizing the future existence of fish in the Sea.
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