A synthesis of aquatic science for management of Lakes Mead and Mohave: U.S. Geological Survey Circular 1381

Lake Mead provides many significant benefits that have made the modern development of the southwestern United States possible. The lake also provides important aquatic habitat for a wide variety of wildlife including endangered species, and a diversity of world-class water based recreational opportunities for more than 8 million visitors annually. It is one of the most extensively used and intensively monitored reservoirs in the United States. The largest reservoir by volume in the United States, it supplies critical storage of water supplies for more than 25 million people in three western states (California, Arizona, and Nevada). Storage within Lake Mead supplies drinking water and the hydropower to provide electricity for major cities including Las Vegas, Phoenix, Los Angeles, Tucson, and San Diego, and irrigation of greater than 2.5 million acres of croplands. Due to the importance of Lake Mead, multiple agencies are actively involved in its monitoring and research. These agencies have a long history of collaboration in the assessment of water quality, water-dependent resources, and ecosystem health. In 2004, the National Park Service obtained funds from the Southern Nevada Public Lands Management Act to enhance this partnership and expand monitoring and research efforts to increase the overall understanding of Lake Mead and Lake Mohave. Participating agencies included the National Park Service, Southern Nevada Water Authority, U.S. Geological Survey, Nevada Department of Wildlife, Bureau of Reclamation, U.S. Fish and Wildlife Service, University of Nevada, Las Vegas, and University of Nevada, Reno. Results of these important efforts have been presented in Lake Mead Science Symposia conducted in 2009 and 2012. The relationships forged by the collaboration led to the development in 2012 of the Lake Mead Ecosystem Monitoring (LaMEM) Work Group, which has formalized the partnership and documented an interagency purpose and mission statement with common objectives for protection of Lake Mead and Lake Mohave water quality and water-dependent resources. This Circular has been developed to summarize the state of the knowledge related to the interests and objectives of the LaMEM Work Group, to inform management and the public of current lake conditions, and identify future needs for monitoring and research. It is hoped that this report will provide a framework for continued long-term investigations and analysis of the environmental health of Lakes Mead and Mohave