The San Diego River Bridge Double Track (SDRDT) project is located on the main line of the Los Angeles‐San Diego‐San Luis Obispo (LOSSAN) Corridor in San Diego, the second busiest intercity passenger rail corridor in the nation. The purpose of the SDRDT project was to construct a 1-mile segment of second main track to connect existing double track segments at each end of the project limits. The centerpiece is an approximately 920-foot-long new double track bridge that replaced an existing segment.

Compatibility Between Projects

The SDRDT project was constructed at the same time, within the same footprint, and combined CMGC delivery with the Mid-Coast Corridor Transit Project, a proposed double track segment of LRT adjacent to the SDRDT. Design, permitting, and construction schedule compatibility between the projects was critical. Site conditions at the bridge crossing presented several technical challenges. Seismic hazard was significant, and the site was underlain with alluvium susceptible to liquefaction spreading to a depth of 85 feet and associated lateral spreading and post-earthquake settlement.

Overcoming Potential Hazards

The preferred alignment and structure were selected through an evaluative criteria approach. Twin steel plate through girder bridges were chosen to minimize foundation costs and construction time. Substructure seismic and geotechnical hazards were overcome with large diameter deep foundations and extensive ground improvement.

Project Results

The Kleinfelder team worked closely with the client to proactively mitigate schedule risk and ensure compatibility with the adjacent project. Construction was completed in 2020.

Project Details

Location:
San Diego, California

Owner:
San Diego’s Regional Planning Agency (SANDAG)