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The North Delta Flood Control and Ecosystem Restoration Project presents unique opportunities for synergy in achieving flood control and ecosystem restoration goals. Components considered for the flood control such as setback levees and flood bypass areas may also be configured to create quality habitat for species of concern in the North Delta area. Through well-integrated flood control and ecosystem restoration, win-win solutions can be achieved that maximize benefits for both. Opportunity for these synergistic benefits is provided in large part by McCormack-Williamson Tract and Staten Island.

McCormack-Williamson Tract plays a key role in North Delta hydraulics and provides potential for well-combined flood control and habitat creation. The property typically floods by overtopping at the Northeast end during large flood events and then breaches downstream in an uncontrolled fashion, causing stress on and failure of adjacent levees and local marina moorings. A North Delta flood solution will allow passing of flood flows through McCormack-Williamson in a way that minimizes flood impacts to the system. Because McCormack-Williamson Tract’s topography varies from roughly minus four to plus five above sea-level, the Tract provides an ideal landscape gradient for a continuum of habitat types as part of the flood control solution.

McCormack-Williamson Tract is owned by the Nature Conservancy (TNC) who is an active participant in the North Delta Improvements planning process. TNC is partnering with UC Davis and DWR North Delta staff to explore integrated flood control and ecosystem restoration on McCormack-Williamson Tract. A key to success of these efforts is addressing scientific uncertainties that affect project planning and design. Uncertainties will be addressed by developing conceptual models, implementing research and pilot projects, and building an adaptive management framework into project planning and implementation.

Staten Island also presents potential opportunities for well-integrated flood control and ecosystem restoration through setback levees or by providing bypass areas for flood waters. The Island currently supports a valuable Sandhill Crane habitat that can be further enhanced. Staten Island is also owned by TNC.

Throughout the planning process, staff will seek opportunities for well-integrated flood control and ecosystem components from willing participants in the North Delta area. These efforts will be supported by ongoing research into critical scientific uncertainties and will provide synergy in achieving flood control and ecosystem restoration in the North Delta area.


  • Addressing changes in land use patterns, i.e. agricultural to non-urban uses such as flood protection and habitat
  • Long-term owner for McCormack-Williamson Tract
  • Funding the Project
  • Federal partner for the Project

Species of Concern

Area Wildlife Area Plantlife
Wildlife Plantlife