Water Authority Completes San Vicente Pipeline Tunnel

Short Title
Water Authority Completes San Vicente Pipeline Tunnel
$342 million project will enhance region’s emergency water storage and conveyance system

The San Vicente Pipeline Tunnel, a key component of the San Diego County Water Authority’s $1.5 billion Emergency Storage Project, is now complete. The 11-mile-long, 8.5-foot-diameter pipeline stretches from Lakeside to Mira Mesa and connects the San Vicente Reservoir to the Water Authority’s Second Aqueduct.

The $342 million San Vicente Pipeline will improve emergency water distribution to water agencies in the southern half of the county.  The project also enhances the Water Authority’s ability to move large quantities of water into storage when imported water supplies are abundant. The pipeline can deliver up to 200,000 gallons of water per minute.

“Completion of the San Vicente Pipeline marks another major step forward for the region’s long-term water reliability,” said Michael T. Hogan, Water Authority Board Chair. “This new pipeline provides greater flexibility for how the Water Authority can store and move water around the county.”

The Water Authority’s Emergency Storage Project is a storage and conveyance system to protect the San Diego region if imported water supplies are disrupted by an earthquake or other disaster.  The project will result in a 90,100 acre-feet increase in emergency water storage, enough to provide an emergency supply of water to the region for up to six months.  The San Vicente Pipeline complements other major pieces of the Emergency Storage Project already in place, including the Olivenhain Pipeline, the Olivenhain Dam, the Olivenhain-Hodges Pipeline and the San Vicente Pump Station.

Final components of the Emergency Storage Project include the raising of the city of San Diego’s San Vicente Dam by 117 feet and building a pump station on the Second Aqueduct in North County. The dam raise project, the tallest dam raise in the nation, is under construction.  The raising of San Vicente Dam is scheduled to be complete in early 2013. 

About 100 local water and business leaders gathered today near San Vicente Reservoir in Lakeside to commemorate the pipeline’s completion and its impact on the region.

“Having a water supply that can be counted on at all times is critical for our region’s $174 billion economy,” said Vincent Mudd, chair of the San Diego Regional Chamber of Commerce and a Water Authority Board member. “Investing in these kinds of visionary, forward-thinking water projects is critical, for in the long run they benefit all of our residents and businesses and help sustain our quality of life.”

Construction on the San Vicente Pipeline began in 2005 at four access points between Mira Mesa and Lakeside. To significantly reduce impacts to nearby communities, construction crews used underground tunneling machines instead of trenching to install the pipe.  Three giant tunneling machines worked 24 hours a day on separate geologic regions of the tunnel. In September 2009, the last tunneling machine broke through the final stretch of rock near the midpoint of the tunnel.

After the tunneling was complete, crews at two of the access points lowered 17-ton, 50-foot sections of steel pipe into the tunnel and moved them – often several miles – into position.  Crews placed 1,145 pipe sections in all.  Once in position, workers encased the exterior of the pipeline in grout to stabilize it and lined the inside with concrete to resist corrosion. Testing was completed in December 2010 to ensure the finished pipe was ready for service. To learn more about the project’s construction, click here.