Groundwater Experts Find Cadiz Valley Water Conservation Project Sustainable

Panel’s findings aid design of southern Calif. groundwater protection program

The Santa Margarita Water District (SMWD) in California announced that the Groundwater Stewardship Committee (GSC) for the Cadiz Valley Groundwater Conservation, Recovery and Storage Project concluded that the project can offer a significant water supply to southern California communities and avoid environmental harm.

The GSC’s report, which includes recommendations for the inclusion of a groundwater protection program, also found that the project can feasibly recover 1.3 million acre-ft of clean groundwater from impending evaporation over a 50-year period of operation, with a continuing conservation benefit of an additional 900,000 acre-ft occurring thereafter. The project proposes to provide a new, reliable water supply for SMWD and other southern California communities by capturing and conserving millions of acre-ft of native groundwater currently being lost to evaporation from an aquifer system in California’s Mojave Desert.

The 12-member GSC reached its conclusions after an extensive review of technical studies conducted as part of the environmental review process. Members of the committee were drawn from various sectors of the professional community, including regulatory institutions, nongovernmental organizations, academia and the groundwater industry.

As part of its work, the panel considered in-depth technical analysis of four potential impact areas: springs, subsidence, air quality and water quality. At the request of SMWD, in consideration of the range of historical estimates of groundwater recharge for the area, the technical analysis was conducted under three different recharge scenarios; 5,000 acre-ft per year (AFY), 16,000 AFY and 32,000 AFY. Even assuming the lowest, most conservative estimate of natural recharge, the group concluded that with long-term management and monitoring, the project will not cause harm to the desert environment due to the unique geologic and hydrologic properties of the watershed and project area.