Project Description


Read an article on the restoration from Bay Nature Magazine, a quarterly magazine dedicated to the exploration of nature in the S.F. Bay Area


An estimated 85 to 90 percent of the historic tidal marshes in the San Francisco Bay-Delta Estuary have been filled or significantly altered over the past two centuries, for urban development, agriculture, and salt production. Commercial salt production in the San Francisco Bay began in 1854. The entire South Bay salt pond complex is spread over an area of approximately 26,000 acres. Salt ponds surround nearly the entire Bay south of the San Mateo Bridge. Cargill operated the ponds in five salt production “plants”: Alviso, Baumberg, Newark #1, Newark #2, and Redwood City.

See a background report on the Cargill Salt Ponds

View Salt Pond acquisition documents

In October 2000, Cargill proposed to consolidate its operations and sell lands and salt production rights on 61 percent of its South Bay operation area. Negotiations headed by Senator Dianne Feinstein led to the signing of a Framework Agreement setting forth the understanding of the parties for public acquisition of these South Bay salt ponds, along with 1,400 acres of crystallizer ponds along the Napa River. The Framework Agreement for the acquisition of these South Bay salt ponds and the 1,400 acres of crystallizer ponds along the Napa River was signed in May 2002 (press release) by the California Resources Agency, Wildlife Conservation Board, California Department of Fish and Wildlife (DFG), California State Coastal Conservancy (Conservancy), US Fish and Wildlife Service (USFWS), Cargill, and Senator Dianne Feinstein (press release). Negotiations regarding the Conveyance Agreement and Phase-out Agreement, which lay out the specific details regarding the property to be acquired and the responsibilities of Cargill for phase-out of salt production operations, were completed in December of 2002. The state of California approved purchase of the property on February 11, 2003.

The USFWS and DFG are the landowners and land managers, and with Cargill’s technical assistance, are currently conducting the initial stewardship of the salt ponds.

See our list of partners

The acquisition and restoration of the South Bay salt ponds has long been a goal of legislators, resource agencies, and non-governmental organizations (NGOs) working to protect San Francisco Bay. Supporters and signatories of the framework agreement include the San Francisco Bay Joint Venture, Save The Bay, National Audubon Society, Citizens Committee to Complete the Refuge, and many other agencies, organizations, and individuals.

Image STS111-376-3. Courtesy of Earth Sciences and Image Analysis Laboratory, NASA Johnson Space Center (

Project Description

See maps of the project area

The State of California and the Federal government are embarked on the restoration of 15,100 acres of Cargill’s former salt ponds in South San Francisco Bay. In the North Bay, 1,400 acres of salt crystallizer ponds are also being restored on the east side of the Napa River (The Napa Salt Ponds are part of a different planning and restoration effort, and are conducted separately from this South Bay Restoration Project).

Acquisition of the South Bay salt ponds provides an opportunity for landscape-level wetlands restoration, improving the physical, chemical, and biological health of the San Francisco Bay. The loss of approximately 85 to 90 percent of the tidal marsh in the San Francisco Bay has led to dramatic losses of fish and wildlife in tidal marsh habitat, decreased water quality and increased turbidity in the Bay. As the Estuary shrank, there were changes to physical processes, increasing the need for dredging and the hazards of flooding.

The South Bay Salt Pond Restoration Project is integrating restoration with flood management, while also providing for public access, wildlife-oriented recreation, and education opportunities. The Project is restoring and enhancing a mosaic of wetlands, creating a vibrant ecosystem. Restored tidal marshes will provide critical habitat for the endangered California clapper rail and the salt marsh harvest mouse. Large marsh areas with extensive channel systems will also provide habitat for fish and other aquatic life and haul out areas for harbor seals. In addition, the restored tidal marshes will help filter out and eliminate pollutants. Many of the ponds will remain as managed ponds and be enhanced to maximize their use as feeding and resting habitat for migratory shorebirds and waterfowl traveling on the Pacific Flyway.

Flood management is integrated with restoration planning to ensure flood protection for local communities. Where feasible, flood capacities of local creeks, flood control channels, and rivers will be increased by widening the mouths of the waterways and reestablishing connections to historical flood plains. As ponds are opened to the tide, levees between the newly created tidal marsh and local communities are built or enhanced to provide flood protection.

The acquisition of such a large area of open space in the South Bay allows for the provision of public access, wildlife-oriented recreation, and education opportunities, being planned concurrently with restoration and flood management. Public uses could include creation of Bay Trail segments for biking and hiking, and provision of hunting and angling opportunities, bird watching, environmental education, and other recreational opportunities.

Project Goals

The South Bay Salt Pond Restoration Project provides the opportunity to improve the physical, chemical and biological health of the San Francisco Bay. The Conservancy will work closely with the USFWS and DFG in meeting the goals of the project: 

  • Restore and enhance a mix of wetland habitats,
  • Provide for flood management, and
  • Provide wildlife-oriented public access and  recreation opportunities.

Project Management

View the project management structure to learn more about the individuals, agencies, and organizations playing a role in the planning process. See Project Managment for key project management documents.

USFWS and DFG are the landowners/managers and, with Cargill’s technical assistance, are currently conducting the interim stewardship of the salt ponds. The Conservancy facilitates long-term restoration planning in partnership with DFG and USFWS. The Conservancy is working closely with the partner agency staff, and is engaging trustee and regulatory agencies, local governments, NGOs, and the public to produce a scientifically-sound, widely-supported plan for implementation.

Project Activities and Timeline

1. Analyze Existing Conditions
A detailed analysis of existing conditions was conducted including topographical/bathymetric surveys of the project area, water and sediment sampling, hydrogeomorphic conditions (sediment, flow, salinity), mapping of existing infrastructure (PG&E towers, Hetch Hetchy aqueduct, etc.), existing wildlife use of salt ponds and adjacent habitats (including birds, mammals, aquatic organisms, and vegetation), flood management needs, capacity and condition of existing water control structures, interim management practices, cultural resources, and existing public access and wildlife oriented recreation opportunities.

2. Develop Restoration Goals and Objectives
The Project Management Team has developed project goals and objectives in coordination with the Stakeholder Forum, Science Team, and Regulatory Agencies. Alternatives are being evaluated to see how well they meet the project objectives. The following regional planning efforts have also guided the development of alternatives:

3. Develop Strategy for Integrating Flood Management
The project team is working with the Santa Clara Valley Water District, Alameda County Flood Control District, San Mateo County Flood Control District, City of San Jose and other affected communities, and the US Army Corps of Engineers to integrate the restoration planning with the flood management planning. See the Shoreline Study website.

4. Develop Alternatives for Habitat Restoration
Restoration alternatives have been defined based upon the overall goals and objectives. Alternatives include phasing options, with and without use of dredged materials, and different long-term habitat mixes of managed ponds and tidal marsh. See Restoration Alternatives for the latest on alternatives development and analysis.

5. Conduct Technical Analysis of Alternatives
Predictive modeling will be conducted to assist in designing an effective restoration strategy and is being used to analyze the impacts of the alternatives. Geotechnical analysis and predictive modeling is being undertaken to evaluate the flood management capabilities of the project. Engineering and design, along with cost estimates of alternatives, will allow the project management team to determine the construction impacts of each alternative, compare the costs and benefits of the alternatives, and determine the feasibility of implementation. See Restoration Alternatives for the latest on alternatives development and analysis.

6. Conduct Environmental Review of Alternatives
Under the CEQA/NEPA process, the project team will develop a comprehensive programmatic EIR/EIS that would also provide sufficient project-specific detail for implementation of the first phase of restoration. As subsequent phases are ready for implementation, project-specific CEQA and NEPA reviews are being completed.

7. Select Preferred Alternative and Design Selected Alternative
Through the technical and environmental analysis, a preferred alternative is chosen for implementation. The alternative is designed for a phased implementation, with the first phase receiving the most detailed design work.

8. Development of a Monitoring, Maintenance, and Adaptive Management Plan
Restoration of the ponds is certain to be conducted in a phased approach over a fairly lengthy period of time. As the project is conducted, problems or opportunities may arise that call for changes in the restoration plan. Adaptive Management will allow for each phase to be conducted based upon the results of previous phases and taking into consideration new understanding of restoration techniques. Monitoring will be critical to ensure that the restoration is achieving its objectives, meeting the requirements of permits, and analyzing future phases of restoration, allowing for adaptive management decisions to be made. See Science for more information about adaptive management and monitoring

9. Acquire all Necessary Federal, State, and Local Permits
The restoration project requires numerous permits. Throughout the project, the Project Management Team is working closely with designated regulatory agency staff to identify all needed permits and ensure that all permits can be obtained.

10. Complete Project Work to Ready Project for the Following Next Steps:
The Project Management Team and Executive Leadership Group, with partner agencies and organizations, will develop an implementation and funding strategy for the restoration, enhancement, and long-term maintenance of the project area.

Opportunities for Public Education and Outreach

Individuals and organizations desiring to contribute technical and scientific expertise in developing the restoration plan should contact Ariel Ambruster at 510-815-7111 or

Communication with and input from the community and interested organizations is being achieved using public meetings and workshops, a website, an email newsletter, press releases, and presentations, to ensure that the public remains informed about project status and is involved in the planning process. The Stakeholder Forum serves as a key forum for public input into the project. See Events and Meetings to find out about upcoming Forum meetings, workshops, and tours, and sign up on our mailing list to stay informed about project activities.

Project Challenges

The restoration and management of the South Bay Salt Ponds presents scientific and technological challenges. Currently there are conflicting goals for restoration of the South Bay Salt Ponds among resource agencies and organizations. Management or infrastructure constraints may also not allow for restoring marsh or retaining ponds in the desired amounts. Restoration involves many complex issues – such as determining the desired mix of managed pond and tidal marsh habitat, the availability of sediment to create dikes and levees, designing flood management structures, protection of existing infrastructure (such as power lines), and controlling invasive plant and animal species. And the ecological and habitat goals must be balanced with human needs, such as opportunities to provide for wildlife oriented recreation. Currently the San Francisco Bay wetlands are frequented by recreational anglers, kayakers, canoeists, birdwatchers, nature photographers, hikers, bicyclists, hunters, environmental educators and their students, and tourists from around the world.