California Aqueduct Milepost 65.77R Canal Liner Repair

California Aqueduct Milepost 65.77R Canal Liner Repair

This canal liner repair will be constructed in conjunction wit the ongoing project at MP 62.26R. The outage in pool 12 for the MP 62.26R project lowered the Aqueduct to Elevation 214.5. The sprinkler system that was installed along pool 12 for the MP 62.26R project will keep exposed concrete above the waterline wet during the outage. A FOC will be relocated by verizon. About 2,200 ft of FOC will be excavated out and relocated in a different alignment. The trench for the new location will be excavated with a backhoe and will be about 3 ft deep, 18 in wide, and 2,300 long Cofferdams will be installed inside the repair site at PM 65.77R; an approx 1,000 ft area between cofferdams will be completely dewatered. About 700 ft of the Aqueduct embankment will be repaired; the failed embankment and concrete lining will be excavated 7 ft below the canal invert and 30 ft into the embankment, as needed, at a 2.5:1 slope. The concrete will be disposed of at an appropriate location and the excavated soil will be placed in a temporary stockpile area. Approx 90,000 cy of soil will be excavated from the embankment. Approx 90,000 cy of soil will be used to backfill the aqueduct embankment and will be sourced either from suitable soils from the embankment excavation or the primary or secondary borrow areas. The primary borrow area is located adjacent to the construction site and the secondary borrow area is located adjacent to the MP 62.26R project site. At the end of the project, excavated and backfilled areas will be re-contoured to conform to the surrounding topography. New PVC pipe will be installed in the groundwater relief system GWRS at MP 62.78R if needed. Ready mix concrete will be delivered and a concrete pump truck will be used to cast the concrete for the liners in place. The outage, which began April 16, 2018, will continue through the end of May 2018. During the outage, work will be conducted 24 hours a day, 7 days per week. After the outage has ended, the remaining work outside the Aqueduct will be conducted during daylight hours. The target date for refilling pool 12 is June 1, 2018. Repairs are needed to ensure efficient State Water project operation.

Merced