Second Addendum to the Final Environmental Impact Report for the Delta Conveyance Project

The California Department of Water Resources (DWR) is proposing refinements to the Delta Conveyance Project previously evaluated in the Delta Conveyance Project Final Environmental Impact Report (Final EIR) certified in December 2023. Specifically, DWR is proposing design or construction refinements that would modify the configuration of the intake structural design and construction methods of the project intakes; lower the tunnel profile extending from Lower Roberts Island to the Bethany Reservoir Surge Basin; reduce the thickness of the diaphragm walls, shaft liners, shaft slab thickness, and diameters of the intake outlet shafts and maintenance and reception shafts; reconfigure the foundation and below-ground structural layout at the Bethany Reservoir Pumping Plant; modify the foundation design for the Bethany Reservoir Surge Basin slab at the Bethany Complex; and reduce the diameter and spacing between the four pipelines that compose the Bethany Reservoir Aqueduct. The project refinements described in the Second Addendum to the Final Environmental Impact Report for the Delta Conveyance Project, in consideration of potential changed circumstances and new information, do not have the potential to create any new significant adverse environmental effects outside of the scope of the analyses already contained in the previously certified Final EIR or substantially increase the severity of effects previously analyzed in the Final EIR. Because no new or substantially more severe effects will occur, a subsequent EIR or supplement to the certified Final EIR is not required pursuant to CEQA.