Caples Lake Dam
Syblon Reid was awarded an emergency design/build contract for modifications to El Dorado County Irrigation District’s Caples Lake dam. In partnership with GEI Consultants, Inc., the contract was awarded to support EID in developing plans to lower and store reservoir water, assist in obtaining resource agency permits, and replace two aging slide gates to restore the safety and operational reliability of the malfunctioning reservoir regulating gates in the outlet shaft system.
In order to gain access to the low level outlet tunnel, a cofferdam system needed to be installed to not only provide a means to access the gates, but also retain adequate amounts of stored water to maintain minimum stream flows below the dam. Once the reservoir was brought down to minimum levels, two 8’ high water filled bladder dams were installed. Not only are these dams extremely environmentally friendly, they are quick to install, taking only one day for the installation. Stream flow was obtained with 3200’ of bypass piping from the cofferdams to the downstream side of Cables Lake Dam. Since the lack of stream flows, even for a short amount of time, would be a major notice of violation, the bypass was installed with automatic backup systems which operated 24/7 for the bulk of the 2 month project duration. Once dewatering occurred, Syblon Reid supported fish rescue operations for the portions of the reservoir that needed to be dewatered.