Drought-stricken California could save up to 14 million acre-feet of water; enough to supply all the state's cities annually

Water Online: California could be saving up to 14 million acre-feet of untapped water – providing more than the amount of water used in all of California’s cities in one year – with an aggressive statewide effort to use water-saving practices, reuse water, and capture lost stormwater, according to a new analysis released today by the Pacific Institute and the Natural Resources Defense Council.

“Our current approach to water use is unsustainable, but that doesn’t mean there isn’t enough water to meet our needs,” said Kate Poole, NRDC senior attorney with the water program. “At a time when every drop counts, we need to employ sensible and cost-effective 21st century solutions that will help us reduce uses today while promising new, resilient supplies for cities and farms tomorrow.”

“As climate change brings more extreme weather, including droughts, ramping up forward-thinking solutions now will help us be more resilient,” said Peter Gleick, president of the Pacific Institute. “With widespread adoption of available water conservation and efficiency improvements, demand can be met more readily, less expensively, and with less pressure on our tapped-out rivers and groundwater basins. Moreover, water reuse and stormwater capture can help boost local supplies.”

NRDC and the Pacific Institute’s issue brief, The Untapped Potential of California’s Water Supply, is a first-of-its-kind statewide analysis examining the significant potential contributions achievable from a combination of improved efficiency in agricultural and urban water use, water reuse and recycling, and increased capturing of local rainwater.

The research also examines the large and growing gap between water use in California and the available water supply. The state suffers from a water deficit in excess of 6 million acre-feet. That amount is unsustainably drawn from the state’s two primary water resources – groundwater and surface waters – each year. On average, the state diverts approximately 5 million acre-feet per year more from the Sacramento-San Joaquin watershed than can be sustained by the estuary, and it overdrafts groundwater by at least 1 to 2 million acre-feet annually. The water deficit is even higher during a drought. Excessive water diversions from the state’s drying rivers and chronic groundwater overdraft have in turn led to shortages for some users, degraded ecosystems, and compromised water quality.

Robert Wilkinson of UC Santa Barbara, report co-author noted, “We have an unprecedented opportunity to do more with less – and we need to take every possible step to do so. By rethinking water management strategies so we work in harmony with the environment and our economy, we’ll be rewarded with dramatic water savings that will offer us local and more sustainable supply for decades to come....

From the National Archives, a 1972 Tomas Sennett photo of a railroad water tank in California