A new but little-known change in California law designating aquifers as “natural infrastructure” promises to unleash a flood of public funding for projects that increase the state’s supply of groundwater.

The change is buried in a sweeping state budget-related law, enacted in July, that also makes it easier for property owners and water managers to divert floodwater for storage underground.

It was exactly the sort of deluge California groundwater agencies have been counting on to replenish their overworked aquifers.

The start of 2023 brought a parade of torrential Pacific storms to bone dry California. Snow piled up across the Sierra Nevada at a near-record pace while runoff from the foothills gushed into the Central Valley, swelling rivers over their banks and filling seasonal creeks for the first time in half a decade.    

Suddenly, water managers and farmers toiling in one of the state’s most groundwater-depleted regions had an opportunity to capture stormwater and bank it underground. Enterprising agencies diverted water from rushing rivers and creeks into manmade recharge basins or intentionally flooded orchards and farmland. Others snagged temporary permits from the state to pull from streams they ordinarily couldn’t touch.

Managers of California’s most overdrawn aquifers were given a monumental task under the state’s landmark Sustainable Groundwater Management Act: Craft viable, detailed plans on a 20-year timeline to bring their beleaguered basins into balance. It was a task that required more than 250 newly formed local groundwater agencies – many of them in the drought-stressed San Joaquin Valley – to set up shop, gather data, hear from the public and collaborate with neighbors on multiple complex plans, often covering just portions of a groundwater basin.

To survive the next drought and meet the looming demands of the state’s groundwater sustainability law, California is going to have to put more water back in the ground. But as other Western states have found, recharging overpumped aquifers is no easy task.

Successfully recharging aquifers could bring multiple benefits for farms and wildlife and help restore the vital interconnection between groundwater and rivers or streams. As local areas around California draft their groundwater sustainability plans, though, landowners in the hardest hit regions of the state know they will have to reduce pumping to address the chronic overdraft in which millions of acre-feet more are withdrawn than are naturally recharged.

Although Santa Monica may be the most aggressive Southern California water provider to wean itself from imported supplies, it is hardly the only one looking to remake its water portfolio.

In Los Angeles, a city of about 4 million people, efforts are underway to dramatically slash purchases of imported water while boosting the amount from recycling, stormwater capture, groundwater cleanup and conservation. Mayor Eric Garcetti in 2014 announced a plan to reduce the city’s purchase of imported water from Metropolitan Water District by one-half by 2025 and to provide one-half of the city’s supply from local sources by 2035. (The city considers its Eastern Sierra supplies as imported water.)