[Lower Walnut Creek] is a highly-engineered trapezoidal channel that requires extensive maintenance, which is often in conflict with habitat values present in the creek. The objective of this study is to identify the best way to balance the competing needs for flood protection and ecosystem restoration. This may include modifying the channel cross section and building setback levees along the lower reaches of the creek to recreate a larger floodplain. The alternatives we develop and evaluate will focus on providing the capacity necessary for flood risk reduction while creating additional wetlands, riparian habitat, and the potential for revegetation throughout the floodplain. The study will also explore the feasibility of providing fish passage beyond the first major drop structure for listed species such as Steelhead and Chinook salmon as well as improving recreation in the area.
The costs of the planning process are shared equally between the federal government (as a special appropriation from Congress) and the Flood Control District. The project’s progress depends heavily on whether Congress provides sufficient funding for the federal side of the project.