Water securityCalifornia Plans to Better Use Winter Storms to Refill Its Aquifers

Published 10 July 2019

With new rules coming into effect, California farmers and municipalities using groundwater must either find more water to support the aquifers or take cropland out of use. To ease the pain, engineers are looking to harness an unconventional and unwieldy source of water: the torrential storms that sometimes blast across the Pacific Ocean and soak California.

With new rules coming into effect, farmers and municipalities using groundwater must either find more water to support the aquifers or take cropland out of use. To ease the pain, engineers are looking to harness an unconventional and unwieldy source of water: the torrential storms that sometimes blast across the Pacific Ocean and soak California.

The general long-term forecast for California as climate change intensifies: more frequent droughts, intermittently interrupted by years when big storms bring rain more quickly than the water infrastructure can handle.

This bipolar weather will have profound implications for the state’s $50 billion agriculture industry and the elaborate network of reservoirs, canals, and aqueducts that store and distribute water. A system built for irrigation and flood protection must adapt to accommodate more conservation. “The effects of climate change are necessitating wholesale changes in how water is managed in California,” the state Department of Stanford’s West Blog notes that water Resources wrote in a June, 2018 white paper.

During droughts, farmers and municipalities pumped groundwater to augment sparse surface supplies. After nearly a century of heavy use, many aquifers are badly depleted. And California’s five-year-old law regulating groundwater basins is nearing a moment of truth: in 2020, sustainability plans are due from agencies managing critically depleted aquifers. They must either find more water to support the aquifers or take cropland out of use. The law – the Sustainable Groundwater Management Act, or SGMA – is beginning to bite. A 2019 study from the Public Policy Institute of California predicted that at least 500,000 acres of farmland will eventually be idled.