The U.S. Forest Service has emptied Hume Lake to allow a contractor to repair and upgrade the historic dam.
The lake remains under a Rough fire closure order, but Hume Lake Ranger District planner Marianne Emmendorfer said the Forest Service is working to modify that directive. When the lake does reopen, the area near the dam will remain closed because of the construction.
People will be allowed to visit the area and walk in the dry lake bed if they want once the closure order is lifted, Emmendorfer said. The lake was drained last week, and Emmendorfer expects the repairs to be completed before the winter storms hit in late December.
The dam was built in 1908 and is the world’s first concrete multiple-arch dam. It created Hume Lake, which originally was used as a water source for a logging operation. The lake is now owned and operated by the Sequoia National Forest and serves as a recreation and tourist destination.
Contractors will inject grout into cracks in the dam’s bedrock foundation to stop water from seeping under the dam. They also will check the dam for any other cracks or abnormalities. When water gets into these crevices, it can erode the concrete.
The construction team will install a waterproof membrane on the upstream face of the dam to prevent water leakage.
Emmendorfer said Hume Lake was last drained in the 1980s and again in the early ’90s for repair work on the dam’s outlet valves. This is the first time a waterproof membrane has been installed, she said, which was a tactic used recently on Shaver Lake’s dam to improve its function.
Meanwhile, Hume Lake Christian Camps’ staff is working to clean up its facilities in the aftermath of the Rough fire. Fall programs through Nov. 20 were canceled as a result of the fire, which burned up to the camp but did not destroy any structures.