Appendix A: Watershed Summaries Preface California’s watersheds supply water for drinking, recreation, industry, and farming and at the same time provide critical habitat for a wide variety of animal species. Conceptually, a watershed is any sloping surface that sheds water, such as a creek, lake, slough or estuary. In southern California, rapid population growth in watersheds has led to increased conflict between human users of natural resources, dramatic loss of native diversity, and a general decline in the health of ecosystems. California ranks second in the country in the number of listed endangered and threatened aquatic species. This Appendix is a “working” database that can be supplemented in the future. It provides a brief overview of information on the major hydrological units of the South Coast, and draws from the following primary sources: • The California Rivers Assessment (CARA) database (http://www.ice.ucdavis.edu/newcara) provides information on large-scale watershed and river basin statistics; • Information on the creeks and watersheds for the ESU of the endangered southern steelhead trout from the National Marine Fisheries Service (http://swr.ucsd.edu/hcd/SoCalDistrib.htm); • Watershed Plans from the Regional Water Quality Control Boards (RWQCB) that provide summaries of existing hydrological units for each subregion of the south coast (http://www.swrcb.ca.gov/rwqcbs/index.html); • General information on the ecology of the rivers and watersheds of the south coast described in California’s Rivers and Streams: Working Toward Solutions. State Water Resources Control Board; • Interviews with County resource managers and planners; • The US Environmental Protection Agency’s “Surf Your Watershed” (http://www.epa.gov/surf/hucinfo) and their index of watershed indicators (http://www.epa.gov/surf/iwi); • The California Environmental Resources Evaluation System (CERES) (http://ceres.ca.gov); • University of California Natural Reserve System (http://nrs.ucop.edu/reserves.html); and • General restoration and conservation plans, materials and information for particular watersheds. Because the presence of wild southern steelhead trout or salmon is an excellent indicator of the general health and integrity of an aquatic system and watershed, the table below also describes Creeks that contain suitable habitat for the species. The ESU for the southern steelhead includes several Gaviota creeks down to Malibu Creek in the greater Santa Monica Bay watershed. A-1 WRP Regional Strategy Appendix A: Watershed Summaries This section does not include a profile of the wetlands of the south coast (available at CWIS) or data from the California Watershed Projects Inventory. The focus of the Appendix is on the 23 major hydrological units of the south coast, which are depicted below: Hydrological Units and Watersheds Associated Wetlands 1. Tijuana River Tijuana Estuary 2. San Diego Bay (key tributaries: Otay River, South San Diego Bay (including Sweetwater Sweetwater River) marsh) 3. San Diego River Famosa Slough 4. Mission Bay (key tributaries: Rose Creek, Mission Bay (Kendall-Jackson marsh) Tecolote Creek) 5. Los Penasquitos Creek Los Penasquitos Lagoon 6. San Dieguito River San Dieguito Lagoon 7. Carlsbad Hydrologic Unit Escondido Creek San Elijo Lagoon San Marcos Creek Batiquitos Lagoon Agua Hedionda Creek Aqua Hedionda Lagoon Buena Vista Creek Buena Vista Lagoon 8. San Luis Rey River San Luis Rey River Estuary 9. Santa Margarita River Santa Margarita River Estuary 10. San Juan Hydrologic Unit San Mateo Creek San Mateo Lagoon San Juan Creek Aliso Creek 11. Santa Ana Hydrologic Unit San Diego Creek Upper Newport Bay, San Joaquin Marsh Santa Ana River Santa Ana River Estuary Huntington Beach Wetlands Bolsa Chica Wetlands Anaheim Bay 12. San Gabriel River Los Cerritos Wetlands 13. Los Angeles River 14. Ballona Creek Ballona Wetlands 15. Santa Monica Bay Hydrologic Unit Topanga Creek Topanga Lagoon Malibu Creek Malibu Lagoon Solstice Creek Trancas Creek Trancas Lagoon 16. Calleguas Creek Mugu Lagoon 17. Oxnard Plain Ormond Beach 18. Santa Clara River Santa Clara River Estuary McGrath Lake 19. Ventura River Ventura River Estuary 20. South Coast Hydrologic Unit Rincon Creek Franklin Creek Carpinteria Salt Marsh 21. Goleta Slough (Atascadero, San Jose, Las Goleta Slough Vegas, San Pedro, Carneros, Tecolotito Creeks) 22. Devereux Creek 23. Gaviota Coast Creeks Devereux Lagoon A-2 WRP Regional Strategy Appendix A: Watershed Summaries Watershed Tijuana River Existing The Tijuana River Watershed is a binational watershed on the westernmost portion of conditions the US - Mexico border. The watershed encompasses approximately 1700 square miles (1245 in Mexico and 455 in the US). The basin contains three surface water reservoirs, various flood control works, and a National Estuarine Sanctuary which is home to several endangered species and is protected by the US federal government. The major drainages include Cottonwood and Campo creeks in the US, and the Rio Las Palmas system in Mexico. Annual precipitation varies from less than 11 inches to 25 inches farther inland near the Laguna mountains. Runoff is captured by the Morena Reservoir and Barrett Lake on Cottonwood creek. There are 3 dams in the watershed controlling 78% of the area: Morena was built in 1912 and Barrett in 1922. In Mexico, Rodriguez dam was built in 1936. The watershed includes eight hydrological areas, including the Tijuana Valley, Potrero, Barrett Lake, Monument, Morena, Cottonwood, Cameron, and Campo areas. The major problem in the watershed is poor water quality. Although discharges from the Tijuana River account for only a small percentage of total gauged runoff to the Southern California coastal ocean, it contains the highest concentrations of suspended solids and cadmium (Cd), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn) among the eight largest creeks and rivers in Southern California. Surface water quality has been affected by runoff from Mexico while ground water contamination has occurred as a result of seawater intrusion and waste discharges. Many of the water quality problems in the Tijuana River watershed are due to diffuse, non-point sources of pollution which may be addressed more effectively through a watershed approach. The water quality problem has worsened in recent years with the substantial growth of Tijuana’s population, along with intensive industrial development associated with the maquiladora (in-bond manufacturing and assembly plants) program in Mexico. Moreover, an industrial pretreatment program similar to one implemented in the US has not been initiated in Mexico. No program equivalent to the US EPA’s National Pollutant Discharge Elimination System (NPDES ) stormwater permitting program exists in Mexico, so the threat of chemical contamination of the Tijuana Estuary is high. Additionally, inadequate infrastructure for the collection, treatment, and disposal of sewage originating in Tijuana has long plagued the watershed, as wastewater flows have chronically outpaced the ability of the infrastructure to handle them. These elements yield transboundary and cross-cultural water quality management challenges. The estuary is one of the largest and most studied wetlands in the South Coast, and is part of the National Estuarine Research Reserve and National Wildlife Refuge programs. The reserve is home to eight threatened and endangered species, including the Light-footed clapper rail, California least tern, Least Bell’s vireo, salt marsh bird’s beak, white and brown pelicans, and numerous shorebirds. Description of Area: 299640.87 acres Watershed Naturally Occurring Waterways: 549.59 miles Resources Percentage of Free Flowing River Miles: 93 % Percentage of River Miles in Protected Lands: 9 % Protected Lands: 7 % Number of Dams: 5 A-3 WRP Regional Strategy Appendix A: Watershed Summaries Number of Stream Crossings: 407 Near-Stream Roads: 181.24 miles Average Precipitation per Year: 19.08 inches Percentage Area above 15% Slope: 18.9 % Number of CalWater Units: 18 WBS TMDL Rivers 1 Number of Special Status Species: 43 Status of The Tijuana River National Estuarine Research Reserve (NERR) encompasses Watershed approximately 2,531 acres of tidally flushed wetland, riparian, and upland habitats Planning lying immediately north of the U.S. - Mexico border. These lands are owned and Efforts managed cooperatively by the California Department of Parks and Recreation (CDPR), U.S. Fish and Wildlife Service (FWS), the City of San Diego, the County of San Diego, and the U.S. Navy. The reserve encompasses 2,500 acres of beach, dune, mudflat, saltmarsh, riparian, coastal sage and upland habitats. Three quarters of the reserve’s watershed is in Mexico. Critical issues confronted by the reserve include habitat restoration, endangered species management, management of wastewater from Mexico, sediment management, and the integration of recreation and habitat conservation and restoration. Hydrological and biological inventories and assessments were conducted and a geographic information system database developed as a foundation for restoration planning. A long-range plan for restoring the estuaries tidal prism and intertidal wetlands was developed and the plan was reviewed in a programmatic EIR/EIS approved and adopted by FWS and the Coastal Conservancy. The plan calls for approximately 500 acres of intertidal wetland restoration to be undertaken in increments using an adaptive management design process, wherein the monitoring and evaluation of projects influence design