During excavation for the 540-foot-long conduit in the 1950s, Reclamation added a concrete liner around sections where the earth foundation was not quite structurally sound, though the liner was not added to the entire stretch of the conduit.
Reclamation provided a three-month timeline to Barnard to complete the work. Crews are working in 40-foot sections to limit the conduit’s exposure to inclement weather. As they do so, 10-foot-tall mechanically stabilized earth walls are placed on both sides of the conduit to create a fixed support system. These walls are made of a plastic geogrid allowing for 18-inch layers of compacted earth material to be placed to stabilize the conduit. Then, a rebar and concrete encasement is added around the pipe for reinforcement.
The outage began on Sept. 25 and is anticipated to be complete by Dec. 18.