LOS ANGELES (AP) A plan to restore the largest coastal wetlands complex in Los Angeles County has received state approval as it advances through a lengthy process.

The California Department of Fish and Wildlife said that it has certified the final environmental impact to restore the Ballona Wetlands Ecological Reserve.

The project aims to restore the ecological function of 566 acres of the reserve, which lies between the Santa Monica Bay community of Playa del Rey and sprawling Marina del Rey.

The area once included 2,000 acres of marshes, mud flats, salt pans and sand dunes, but currently only 577 acres remain, according to Fish and Wildlife.

The department said the wetlands has been hugely degraded by human impacts, and the restoration will not only preserve sensitive habitat but build in resilience against sea level rise.

Restoration planning by Fish and Wildlife and partners has been under way for years and will now proceed toward a final design, but will still need an estimated two and a half years to win a permit from the U.S. Army Corps of Engineers and complete a federal environmental review document, the department said.

Other approvals, including by the California Coastal Commission, also are required.