Interstate 405 at San Gabriel River Bridge Scour Mitigation Project

Interstate 405 at San Gabriel River Bridge Scour Mitigation Project

The California Department of Transportation (Caltrans) proposes a bridge scour maintenance project at the Interstate 405 (I-405) / Interstate 605 (I-605) interchange - a complex of three (3) bridges that traverse the San Gabriel River at the Los Angeles County/Orange County line. Two of the three bridges exist within the jurisdiction of Caltrans District 7 - Los Angeles (Bridge No. 53-1185 and Bridge No. 53-1737H from post mile 0.2/0.3), and the third bridge exists within the jurisdiction of Caltrans District 12 - Orange County (Bridge No. 53-413F at post mile 24.11). The scope of work for all three bridges includes 1) retrofit of bridge substructure foundation by constructing pier footing extensions at Pier 3 and Pier 4 at each bridge, 2) reinforcement of new footing extensions through placement of new Cast-In-Drilled-Hole (CIDH) piles, and 3) armoring of substructure retrofit through placement of rip-rap/rock protection around each pier.

Long Beach, Los Alamitos, Seal Beach

Los Angeles, Orange

Southern California

California Air Resources Board (ARB), California Coastal Commission (CCC), California Department of Conservation (DOC), California Department of Fish and Wildlife, Marin Region 7 (CDFW), California Department of Fish and Wildlife, South Coast Region 5 (CDFW), California Department of Forestry and Fire Protection (CAL FIRE), California Department of Parks and Recreation, California Department of State Parks, Division of Boating and Waterways, California Department of Toxic Substances Control (DTSC), California Department of Transportation, District 7 (DOT), California Department of Transportation, Division of Aeronautics (DOT), California Department of Transportation, Division of Transportation Planning (DOT), California Department of Water Resources (DWR), California Energy Commission, California Governor's Office of Emergency Services (OES), California Highway Patrol (CHP), California Native American Heritage Commission (NAHC), California Natural Resources Agency, California Public Utilities Commission (CPUC), California Regional Water Quality Control Board, Los Angeles Region 4 (RWQCB), California State Lands Commission (SLC), Office of Historic Preservation, San Gabriel and Lower Los Angeles Rivers and Mountains Conservancy (RMC), State Water Resources Control Board, Division of Water Quality

Use Permit, Coastal Permit

Aesthetics, Biological Resources, Coastal Zone, Cultural Resources, Cumulative Effects, Drainage/Absorption, Flood Plain/Flooding, Geology/Soils, Greenhouse Gas Emissions, Hazards & Hazardous Materials, Hydrology/Water Quality, Mineral Resources, Public Services, Recreation, Transportation, Vegetation, Wetland/Riparian, Wildlife