The restoration of degraded ecosystems requires assessment throughout the restoration effort. This information is used to help direct resource management activities to support restoration. A focus of the California Water Science Center is research which contributes to the restoration of tidal wetlands. Expanding towns and cities have claimed major parts of California's tidal wetlands. Restoring these wetlands will have benefits for ecosystems that have declined during the last century. Successful efforts will also promote greater ecological health for the benefit of everyone.