Southern California Needs a Varied Approach to Reduce Dependence on Imported Water, Report Says

Southern California Needs a Varied Approach to Reduce Dependence on Imported Wat

Southern California should adopt a diverse range of water conservation strategies and a regional groundwater plan to reduce its dependence on imported water, according to a newly-released report from the University of Southern California.

The report, “Water Supply Scarcity in Southern California,” was published by the USC Center for Sustainable Cities. It examined water management strategies over a two-year period in three large water districts in Southern California – the Los Angeles Department of Water and Power (LADWP), the Cucamonga Valley Water District and the Huntington Beach Utilities Department. 

The analysis found the districts still rely on imported water from the Sacramento-San Joaquin River Delta and the Colorado River as their main water source. In the case of LADWP, 52% of its water is imported through the Metropolitan Water District of Southern California, 36% comes from the Los Angeles Aqueduct, 11% from groundwater and less than 1% of its water is recycled.

The report stressed while the districts have water conservation strategies in place, they may not be aggressive enough to meet water supply challenges that will be created by climate change, possible disruptions of water from the Sacramento-San Joaquin Delta and diminishing snowpack in the Sierra Nevada. The report credited LADWP for its plan to grapple with water shortages in the future. Strategies include cleaning up the San Fernando Basin – its source of groundwater – and implementing tiered pricing for water use.

The report also found that water conservation strategies vary in cost-effectiveness, with some strategies working in one district, but not in another. The report made several recommendations including: investing in technological innovations to reduce urban outdoor water irrigation, having water agencies meter outdoor water use for all accounts, improving existing pricing structures to more fully realize reductions in water use and developing a Southern California regional groundwater strategy.

The full report is available here.

The research was funded by the Haynes Foundation. Lowell Stout of USC, Marina Alberti of the University of Washington and Joshua Newell of the University of Michigan contributed to the report.