A project to maintain dam safety and increase reservoir capacity by removing and hauling away sediment from upstream of one of Yuba Water Agency’s diversion dams is the winner of the 2018 American Society of Civil Engineers, Sacramento Section Outstanding Construction Project of the Year award.
In less than two months, the agency removed approximately 12,000 cubic yards of sediment from behind Log Cabin Dam, which is located in the Yuba County foothills in the remote community of Camptonville. The sediment buildup was a result of previous winters’ storms and heavy flows in the creek.
In addition to working in steep terrain, the project also required careful cooperation with the California Department of Fish and Wildlife and all of the agencies involved to rescue and relocate foothill yellow-legged frogs, fish, and other aquatic vertebrates using the waterway. To do this, water was diverted from the creek to bypass the dam, and then a road was constructed to gain access to where the sediment had built up.
“It was challenging to bypass the water in this remote location because we had to do it without any interruption in flows to maintain habitat downstream,” said Yuba Water Agency Chief Dam Safety Engineer Tim Truong. “It could not have been done without the support, communication, and coordination between all the agencies, consultants, and the contractor.”
After successfully diverting the water away from the dam, the sediment was excavated and allowed to dry at a temporary location before it was then loaded into trucks and transported to a final stockpile near Yuba Water Agency’s New Bullards Bar Dam and Reservoir.
The Log Cabin Sediment Removal Project was completed without any injuries to workers, while successfully rescuing and relocating wildlife, and maintaining flows to avoid harming downstream habitat.