Custom Built Installation Equipment for Relining Pre-stressed Concrete Cylinder Pipe Minimizes Construction Schedule

The San Diego County Water Authority (Authority) is a water wholesaler delivering imported water to the San Diego region. The imported water is delivered through several large diameter pipelines, sized up to nine-feet in diameter, to meet 70 to 90 percent of the regions annual demand. As part of the Authority's mission "to provide a safe and reliable supply of water to San Diego County", and to mitigate deteriorating pre-stressed concrete cylinder pipe (PCCP), approximately 686 meters (2,250 feet) of welded steel liner was installed inside the Second Aqueduct's 1753 mm (69-inch) diameter Pipeline 3. Installation occurred in the community of Rancho Penasquitos within the Authority's right-of-way. The pipeline was taken out of service to perform liner installation. An aggressive construction schedule of six months was implemented to restore service to Pipeline 3 and to meet seasonal demand increases on the Aqueduct System. Liner installation was identified during project design as the critical task for completion of construction on schedule. The Authority's estimated construction schedule allowed for installation of three liners per day, or approximately two months total, leaving four months to complete all other construction tasks.