Pacific Southwest, Region 9
Serving: Arizona, California, Hawaii, Nevada, Pacific Islands, Tribal Nations
Watershed Priorities
National Links
San Francisco Bay Delta Estuary
On this page:
- Hot Topics
- Watershed Information
- EPA Activities
- Watershed & Technical Documents
- Pollutants
- Total Maximum Daily Loads
- Partners
- Contact Information
Hot Topics
- Vulnerability Assessments in Support of the Climate Ready Estuaries Program: A Novel Approach Using Expert Judgment, Volume I: Results for the San Francisco Estuary Partnership
- Climate Ready Estuaries, Volume I: Tables and Figures
Watershed Information
The San Francisco Bay Delta Estuary (Bay Delta) is the largest estuary on the west coast of North America. Its 4-million acre watershed covers more than 40% of California and includes the drainage basins for the Sacramento and San Joaquin Rivers, the Sacramento-San Joaquin Delta, and the San Francisco Bay (including Suisun and San Pablo Bays).
The Bay Delta is a valuable economic and ecological resource. It provides drinking water to 25 million Californians, irrigation to 4.5 million acres of agriculture, and hosts important economic resources such as the hub of California's water supply infrastructure, Port of Oakland, deep water shipping channels, major highway and railroad corridors, and energy lines. The Bay Delta ecosystem supports 750 species of plants, fish, and wildlife including several endangered and threatened aquatic species such as delta smelt, steelhead, spring run Chinook salmon, winter run Chinook salmon, and others. Two-thirds of California's salmon pass through Bay Delta waters, and at least half of its Pacific Flyway migratory water birds rely on the region's wetlands.
The Bay Delta Estuary is confronted by a wide range of challenges that are magnified and concentrated in the Delta, the heart of California's water system. Delta resources are in a state of crisis. Decades of pollution and resource extraction have lead to sharp declines in Bay Delta fisheries contributing to the collapse of California's salmon fishing industry. Multiple years of drought conditions have reduced water supply for agriculture and cities contributing to difficult economic conditions. Sub-sea level Delta islands, protected by aging levees, leave homes, communities, farms, transportation corridors, and energy infrastructure vulnerable to sea level rise, levee collapse, and flooding. A major earthquake would cause a catastrophic failure of the levee system jeopardizing lives, cities, and water supplies from the Delta to San Diego.
EPA Activities
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- Ensuring that water quality regulations in the Delta sufficiently protect beneficial uses, such as drinking water, fish and wildlife habitat, and agriculture.
- Assessing the effectiveness of water quality programs in protecting Bay Delta Estuary aquatic species and ecosystem.
- Administrating the San Francisco Bay Water Quality Improvement fund. This is a competitive grant program to support water quality improvement projects for the San Francisco Bay Area.
- Advanced Notice of Proposed Rulemaking for Water Quality Issues in the San Francisco Bay/Sacramento-San Joaquin Delta Estuary Comment period open until April 25, 2011.
- Reviewing Water Quality Control Plans produced by California's State Water Resources Control Board and Regional Water Quality Control Boards for Bay Delta, San Francisco Bay, and Central Valley
- Providing technical, financial and regulatory assistance for the development and implementation of Total Maximum Daily Load (TMDL) objectives and watershed plans to restore impaired waters and protect aquatic ecosystems.
- Assessing the effectiveness of water quality programs in protecting Bay Delta Estuary aquatic species and ecosystem.
- Supporting the State's priority activities that will address water supply and environmental problems in the Bay Delta.
- California State Water Resources Control Board approved a report determining new flow criteria for Delta ecosystem that are necessary to protect public trust resources.
- Delta Flow Criteria Presentation (PDF) (24 pp, 2.3M): Presentation by Dr. Bruce Herbold, EPA R9 Fisheries Biologist, to the State Water Resources Control Board at the March 22 – 24 Delta Flow Criteria hearing.
- Delta Flow Criteria Written Comments (PDF) (4 pp, 54K): Written comments by Dr. Bruce Herbold, EPA R9 Fisheries Biologist, to the State Water Resources Control Board following the March 22 – 24 Delta Flow Criteria hearing.
- EPA written comments on SWRCB Strategic Workplan for Activities in the San Francisco Bay/Sacramento-San Joaquin River Delta July 9, 2008 (PDF) (4 pp, 40K)
- EPA comments at SWRCB March 19, 2008 public workshop on development of San Francisco Bay/Sacramento-San Joaquin River Delta Strategic Workplan (PDF) (3 pp, 30K)
- California State Water Resources Control Board approved a report determining new flow criteria for Delta ecosystem that are necessary to protect public trust resources.
- Engaged in a renewed federal partnership focused on identifying long-term solutions for Delta resource management problems by working with the State of California (State) and a diverse set of stakeholders.
- Interim Federal Action Plan Status Update for the California Bay Delta: 2011 and Beyond (PDF) (23 pp, 1.2M)
- Interim Federal Action Plan for the California Bay Delta (PDF) (23 pp, 216K, )
- California Bay - Delta Memorandum of Understanding among Federal Agencies (PDF) (5 pp, 2.5M )
- Participation in the Bay Delta Conservation Plan and other large-scale Bay Delta projects.
- Coordination with Delta Stewardship Council
- Improving comprehensive water quality monitoring & assessment in the Central Valley to provide a sound scientific basis for targeting water quality improvement activities with a special emphasis on the San Joaquin River Basin.
- Ongoing support for the San Francisco Estuary Partnership , one of 28 estuaries receiving support nationally from EPA as part of the National Estuary Program.
- Ongoing participation with key partnerships such as the Interagency Ecological Program , San Joaquin Restoration Program , Central Valley Joint Venture.
Watershed & Technical Documents
- State Water Resources Control Board Strategic Work Plan for Activities in the San Francisco Bay/Sacrament-San Joaquin Delta Estuary (PDF) (97 pp, 3.7M)
- California Department of Fish and Game Quantifiable Biological Objectives and Flow Criteria for Aquatic and Terrestrial Species of Concern Dependent on the Delta (23 November 2010)
- Managing Freshwater Discharge to the San Francisco Bay/Sacramento-San Joaquin Delta Estuary, the Scientific Basis for an Estuarine Standard: Conclusions and Recommendations of the Scientific, Policy, and Management Communities of the Bay/Delta Estuary. San Francisco Estuary Project (1993) (PDF) (126 pp, 6.0M)
- Vulnerability Assessments in Support of the Climate Ready Estuaries Program: A Novel Approach Using Expert Judgment, Volume I: Results for the San Francisco Estuary Partnership (PDF)
- Climate Ready Estuaries, Volume I: Tables and Figures
- Water Quality Control Plan for the SF Bay Delta Estuary 2006 (PDF) (60 pp, 11.7M)
- Water Quality Control Plan for San Francisco Bay (PDF) (294 pp, 62M, very large file)
- Water Quality Control Plan for the Sacramento and San Joaquin River Basins
- Bay Delta Conservation Plan
- Delta Vision
- San Francisco Estuary Project CCMP (PDF) (245 pp, 853K)
- San Joaquin Restoration Program
Water Quality Impairments
Section 305(b) of the Clean Water Act requires states to assess and report on the water quality status of waters within the states. Section 303(d) requires states to list waters that are not attaining water quality standards. This is also known as the list of impaired waters. This information is reported to Congress on a nationwide basis.
Poor water quality in the Bay Delta Estuary and its tributaries affects terrestrial and aquatic ecosystems, drinking water, recreation, industry, agriculture, and the local and state economy. The State of California collects data on contaminants that degrade water quality to generate its Clean Water Act Section 303(d) list of water bodies with designated use impairments.
All of the waters within the Bay Delta Estuary are listed as impaired by at least one factor, either due to the presence of pollutants at unacceptable levels or the lack of maintaining certain conditions such as adequate levels of dissolved oxygen. Impairments in Bay Delta Estuary waters include:
- Pesticides (e.g., diazinon, DDT)
- Metals (e.g., mercury, zinc, selenium)
- Manufacturing compounds (e.g., dioxin, polychlorinated biphenyls, furan)
- Pathogens (e.g., fecal coliform)
- Nutrients (e.g, ammonia, organic carbon)
- Low dissolved oxygen
- Trash
- Exotic Species
- Salinity
- Temperature
- Toxicity from unknown sources
Some pesticides and metals are legacy problems, such as the banned organochlorine pesticide DDT and mercury from abandoned mines. Most contaminants contributing to poor water quality in the Bay Delta Estuary are the result of current-use compounds from industrial, agricultural, urban, transportation, and natural sources. In addition, there is growing concern about new classes of contaminants, such as pyrethroid pesticides, pharmaceuticals and personal care products.
A 2010 list of water quality impairments in Bay Delta Estuary waterways and other California waterways is available at the California State Water Resources Control Board web site. And more information regarding EPA activities with impaired waters is available on EPA Region 9’s Monitoring, Assessment, and TMDLs webpage.
Total Maximum Daily Load (TMDL) Programs
A “total maximum daily load” (TMDL) program identifies the maximum amount of a pollutant that can be added to a water body without exceeding water quality standards. States must establish TMDLs for waters where pollutants are “preventing or expected to prevent attainment of water quality standards.” Under Section 303(d)(2), EPA is required to review and approve or disapprove TMDLs established by states for listed waters. In its review, EPA takes into consideration the legal and technical adequacy of the TMDL, which includes wasteload allocations for point sources, load allocations for nonpoint sources, and an implementation schedule. Implementation is the responsibility of states. In California, the Porter Cologne Act requires that a TMDL include an implementation plan.
TMDLs established pursuant to Section 303(d)(1) for impaired waters are not self-executing. Limitations in loadings identified for point sources (“waste load allocations”) are enforced through permits issued pursuant to Section 402 of the CWA. Limitations in loadings identified for non-point source pollution (i.e., “load allocations”), on the other hand, may only be “required” under state law.
TMDLs are developed by the San Francisco Bay and Central Valley Regional Water Quality Control Boards for waters within the Bay Delta Estuary but are not final until approved by the California State Water Resources Control Board and EPA. EPA has approved TMDLs for salinity, boron, mercury, selenium, diazinon, chlorpyrifos, pathogens and low dissolved oxygen to address impairments affecting the Delta. The Central Valley RWQCB is developing a TMDL for salinity in the San Joaquin River upstream of Vernalis, as well as a pesticides TMDL for the Central Valley. Below are links to the Central Valley and San Francisco Bay Regional Water Quality Control Board TMDL web sites that contain detailed information about pending and approved TMDLs for waters in the Central Valley, including the Bay Delta Estuary and its upper watershed, and in the San Francisco Bay which includes Suisun Bay immediately downstream of the Delta. More information regarding EPA Region 9 activities with TMDLs in California is available on EPA Region 9’s Monitoring, Assessment, and TMDLs webpage.
TMDLs in the Central Valley
TMDLs in the San Francisco Bay
Partners
Federal
- Army Corps of Engineers Sacramento District
- Bureau of Reclamation
- Central Valley Joint Venture
- National Marine Fisheries Service Sacramento Office
- Natural Resources Conservation Service
- US Fish and Wildlife Service Bay Delta Office
- USGS Water Quality of the San Francisco Bay
State
- California Dept. of Fish and Game Ecosystem Restoration Program
- Central Valley Regional Water Quality Control Board
- Delta Science Program
- Delta Stewardship Council
- Department of Water Resources Bay Delta Office
- Interagency Ecological Program
- San Francisco Bay Regional Water Quality Control Board
- San Francisco Bay Conservation and Development Commission
- State Water Resources Control Board Bay Delta Program
Other
- National Academy of Sciences, National Research Council
- San Francisco Estuary Partnership
- San Francisco Estuary Institute
- San Joaquin Restoration Program
SF Bay Delta Team EPA Contacts
Erin Foresman (foresman.erin@epa.gov), Bay Delta Environmental Scientist & Policy Coordinator
(916) 557-5253
Bruce Herbold (Herbold.Bruce@epa.gov), Bay Delta Fisheries Biologist & Senior Scientist
(415) 972-3460
Carolyn Yale (Yale.Carolyn@epa.gov), San Joaquin River Basin Lead
(415) 972-3482
Luisa Valiela (Valiela.Luisa@epa.gov), San Francisco Bay Lead
(415) 972-3400
Erica Yelensky (Yelensky.Erica@epa.gov), San Francisco Bay Outreach Coordinator
(415) 972-3021
Sam Ziegler (Ziegler.Sam@epa.gov), Watersheds Office Manager
(415) 972-3399
Tim Vendlinski (Vendlinski.Tim@epa.gov), Senior Policy Advisor, Water Division
(415) 972-3469
Karen Schwinn (Schwinn.Karen@epa.gov), Associate Director, Water Division
Bay Delta Team Manager
(415) 972-3472
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