Lower Wildcat Creek Restoration Project, CP#25-31

Lower Wildcat Creek Restoration Project, CP#25-31

The purpose of the Lower Wildcat Creek Restoration Project (Project) is to restore flood conveyance capacity of an approximately 4,500-foot stretch of lower Wildcat Creek to restore fish passage within that reach, and to enhance the vegetated riparian habitat. This will be accomplished by removing excess sediment and vegetation so that water can move more freely through the low-flow channel and adjacent high-flow floodplain of the creek. The Project consists of the following elements: • Remove excess sediment and debris from select reaches of the creek. Within the creek’s previously excavated low-flow channel, recently accumulated sediment which has deposited to depths up to approximately 2-6 feet and debris jams or other obstructions that impede fish passage and/or flows will be removed. Within the north floodplain between the low-flow channel and the trail, silt and other recent deposits will be excavated up to approximately 1-5 feet where necessary to improve flood capacity. • Remove vegetation and trees, predominantly willows, that have spread onto the northern floodplains beyond established maintenance zones of the riparian forest that flanks the established low-flow channel. The Project will promote a shift of species in the riparian corridor to ecologically desired native species with lower hydraulic roughness that do not significantly impede stream flows. This will be done by removing willows that trap sediment, and planting tree species that allow sediment to flow through. Trees growing in the channel that block the flow of the creek will also be removed. • Install several small drainage swales within the floodplain to help return water back to the creek’s low-flow channel and reduce the formation of unwanted secondary low-flow channels on the floodplain. Where they connect to the low-flow channel, these drainage swales will create habitat alcoves that add ecological value and help to reduce fish stranding following high-flows. Several other channel stabilizing measures are proposed to prevent a secondary low-flow channel from forming on the unshaded floodplain. • Create in-stream habitat features for fish, including two log habitat structures that also help to retain baseflow within the low-flow channel and fish resting pools. • Enhance the adjacent riparian corridor habitat through removal of invasive plants and installation of native vegetation. • Increase the level of flood protection from approximately 700-800 cubic feet per second (cfs) to approximately 1,130 cfs in the Project reach.

Unincorporated North Richmond

Contra Costa

Northern California, San Francisco Bay Area, Unincorporated

Contra Costa