The largest concrete dam raise in the United States

San Vicente Dam Raise

In the early 90s, the San Diego region was importing more than 90% of their water from hundreds of miles away using pipelines, tunnels, and pump stations. But because of the constant risk of natural disasters (ranging from wildfires to earthquakes) coupled with global climate change effects and the California drought, the reliability of this water supply system was threatened.

Ensuring the community would have an adequate and dependable supply of local water storage was the highest priority for the San Diego County Water Authority (SDCWA). To be proactive, the SDCWA executed a 20-year, $1.5 billion emergency and carryover storage project (E&CSP).

During the final phase of the project, we designed the 117-feet-raise (35.7 metre) of the existing 219-feet-high (67 metre) San Vicente Dam. The dam was raised using roller-compact concrete (RCC)—a time-saving alternative that enabled construction to proceed around the clock. By using an on-site quarry to provide aggregates for the RCC, we promoted environmental stewardship and eliminated more than 100,000 truck deliveries from off-site sources.

Working beside the SDCWA, our team helped double the size of the existing San Vicente Reservoir, providing an additional 152,000 acre-feet of water storage capacity for emergencies and future droughts.