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What We Do

The Delta Ecosystem Enhancement Section is an interdisciplinary team of scientists and engineers who develop, enhance, and maintain ecologically effective habitats that benefit the overall ecological health of the region and its native species by:

  • Coordinating environmental compliance requirements for the Delta Levees Program, including Habitat Mitigation.
  • Implementing the Delta Levees Program's ecosystem enhancement mandate, serving as the Program’s environmental arm and having a primary role in providing environmental oversight for Reclamation District projects funded by the Program.
  • Working with other local, state, and federal entities to improve habitat conditions in the Delta and Suisun Marsh.
  • Planning and coordinating habitat monitoring and land management of Program Habitat Enhancement sites.
  • Reviewing and managing Demonstration projects designed to test the feasibility and effectiveness of new environmentally friendly methods of providing flood protection, levee stability, and habitat benefits. This was established by California Senate Bill 1065 (March 26, 1992), stating that the Reclamation Board, Resources Agency, Department of Fish and Wildlife (then Department of Fish and Game), and Department of Water Resources coordinate the implementation of Demonstration Projects.

Delta Ecosystem Enhancement staff work directly with the DWR Delta Levees Office, in partnership with staff in the California Department of Fish and Wildlife's Delta Levee Habitat Improvement Program, reclamation districts, and other government and local agencies.

The Delta Levees Office includes the Delta Levees Program (Special Projects and Subventions) in addition to programs focusing on habitat impacts and development in the North Delta and West Delta. The Delta Ecosystem Enhancement section's environmental responsibilities arise from the State's support for mitigating environmental effects of levee maintenance and habitat improvement in the Delta under the California Water Code. View Foundations in State Law for more information pertaining to the Delta Levees Program's specific authorization.

The California Department of Fish and Wildlife's Delta Levee Habitat Improvement Program is the regulatory program ensuring that SB 34 (1988) and AB 360 (1966) habitat impacts occurring from the Delta Levee Program's projects are accounted for and mitigated. The California Department of Fish and Wildlife works closely with Delta Ecosystem Enhancement to benefit aquatic species in the Delta and to implement the net long-term habitat improvement mandate.


The Delta Ecosystem Enhancement Section operates as the environmental arm of the Delta Levees Program and has a primary role in providing environmental oversight for Reclamation District projects funded by the Program. Staff review and manage habitat mitigation, enhancement, and demonstration projects. The primary objective of these projects is to provide habitat and ecosystem benefits (such as improved hydrology and nutrient supply) for native species.


Mitigation projects are implemented to offset habitat impacts from levee maintenance and improvement projects. California Water Code §12314(c) and §12987(c) state that the Delta Levees Program projects will not result in a net long-term loss of riparian, fisheries, or wildlife habitat. For further information about habitat types, see Delta Levees Significant Habitat Types.

Mitigation needs for individual islands are accomplished either through sites built on-island or through the purchase of habitat offsets from approved mitigation banks. The Delta Ecosystem Enhancement Section supports a variety of habitat mitigation projects in partnership with reclamation districts, the California Department of Fish and Wildlife, and other local, State, and federal entities.

Historically, most reclamation districts' mitigation obligations have been met through individual on-island mitigation projects. It is becoming increasingly encouraged for reclamation districts to obtain their mitigation obligation through larger, more biologically appropriate mitigation opportunities, such as established mitigation banks.

The Bulk Credit Program is the Delta Levees Program's first effort in assisting participating reclamation districts with mitigation requirements resulting from their Subventions and Special Projects levee repair and improvement projects. Reclamation District 830, Jersey Island, was awarded funding to purchase approximately 100 acres (credits) from the Cosumnes Floodplain Mitigation Bank at a discounted (bulk) rate. These mitigation credits are now available for all qualified reclamation districts through RD 830. The Bulk Credit Program provides high-quality, biologically-effective, and cost-effective mitigation credits for the Delta Levees Program participants' needs.

For more information about habitat mitigation projects for the Delta Levees Program, email or call 916-651-7005.


The mission of the Delta Levees Program Habitat Enhancement is "to restore and enhance sustainable and diverse habitats (particularly shaded riverine aquatic, channel margin, wetlands, riparian forest, scrub-shrub, and uplands) in a mosaic that benefits the overall ecological health of the region and its native species."

Long-term habitat enhancement through the Delta Levees Program is primarily the responsibility of the California Department of Fish and Wildlife and DWR's Delta Ecosystem Enhancement environmental and engineering staff. California Water Code §12314(d) and §12987(d) requires the Program to contribute to long-term habitat improvement in the Delta, with net benefit for aquatic species.

An enhancement project may be independent of a levee project or it may be part of a multi-benefit project that includes both levee work and a habitat enhancement component. Program funds are used to implement an enhancement project on behalf of the Delta Levees Program and all participating reclamation districts.

Reclamation districts have the option of directly implementing enhancement projects through Directed Actions, or through submitting a proposal under DWR's Project Solicitation Process; either option utilizes the Program's "local assistance" funding granted to a district.

Active Projects