Enhanced recharge project secures local water resources

The San Bernardino Valley Municipal Water District’s Santa Ana River Enhanced Recharge Project was designed to divert 500-cubic-foot per second of water from the Santa Ana River released from the Seven Oaks Dam, located in Highland, California. GHD’s team prepared the final design documents for Phase 1A of the project, including a new facility for a diversion structure, inlet channel, sedimentation basin, effluent structure, flow control structure, and effluent pipeline. The new facilities enable the Valley District to divert clarified Santa Ana River water to their existing groundwater recharge basins, or directly into the Metropolitan Water District of Southern California Foothill Feeder, through a new 96-inch steel pipeline.

Outcomes

• Provided the Valley District operational flexibility to maximize the local water supply and increase the overall water quality
• Reinforced concrete diversion structure fitted with five 60-inch tall motor operated slide gates to regulate flow
• Approximately 500-linear foot of new 66-foot wide trapezoidal inlet channel armored with ¼-ton rock
• Approximately 800-foot long by 194-foot wide sedimentation basin with a 25-acre-foot capacity with rock armored sloped walls to mitigate turbidity levels from the Santa Ana River
• Installed floating debris boom system across 194-foot wide section of the sedimentation basin for protection of downstream facilities
• Reinforced concrete effluent structure measuring 167-foot long by 17-foot wide by 22-foot deep, fitted with a 143-foot long weir to decant clarified river water and divert effluent flows
• Reinforced concrete flow control valve vault measuring 32-foot long by 26-foot wide by 17-foot deep housing a 78-inch motorized butterfly valve and pipeline maintenance access hatch
• Approximately 3,300-linear-foot of 96/78-inch welded steel water transmission piping