Groundwater Recharge in the San Joaquin Valley

Overdraft has caused big problems in the San Joaquin Valley—and in our drought-prone state, groundwater recharge is one of the most promising ways to protect ourselves against hotter, longer dry periods. So are we socking away enough water during the wet periods? That was the subject of our event on Tuesday, June 11, “Replenishing Groundwater in the San Joaquin Valley.”

In 2023, we asked San Joaquin Valley water agencies about their recharge activities and compared their responses to a similar survey from 2017, which was a comparably wet year. In an event last week, PPIC Water Policy Center associate director Caity Peterson kicked things off with a presentation of findings from the updated survey.

Has much changed since the first survey? In 2017, the Sustainable Groundwater Management Act had yet to get off the ground. Now, said Peterson, groundwater sustainability agencies (GSAs) are fully formed, and groundwater sustainability plans (GSPs) are complete. The data show that recharge volumes rose by a whopping 17%: some 7.6 million acre-feet (maf) of water was put toward recharge valley-wide in 2023.

Many factors contributed to this impressive growth, Peterson said. Among them was groundwater accounting, which was once a rarity in the valley. “It’s difficult to overstate,” she said, “how much progress has been made on groundwater accounting methods.”

The panelists shared anecdotal evidence that backed up the conclusion that recharge is on an upswing in the valley. Jeevan Muhar, manager-engineer of the Arvin-Edison Water Storage District, said that new infrastructure helped his district recharge an additional 35,000 acre-feet of water in 2023, compared to 2017. The district also participated in more on-farm recharge than in the past.

Money, Muhar said, was key: “We incentivized some of our growers to farm with water. We paid them $40 an acre-foot to put water on fallowed fields.” And he said that building partnerships paid off: the district even got three CalTrans basins hooked up and ready to take water for recharge.

Jon Reiter, a grower and solar developer who’s worked in western and eastern Fresno County and southern Kern County for years, echoed Muhar’s comments. “I’ve seen two key things evolve since SGMA’s passage,” he told the virtual audience. “One is the development of landowner recharge programs, and the second is the evolving market for buying water for recharge in a wet year in preparation for dry years.”

Reiter said that some water agencies’ inexperience with recharge didn’t appear to block efforts in 2023. He cited the example of Westlands Water District, which had almost no history of groundwater banking or recharge. Reiter said that in 2022, the newly elected board focused its platform on recharge, launching a landowner recharge program in 2023. It incentivized landowners with pumping credits, cash payments, or a combination—and it was a roaring success. By the end of the water year, the district went from zero to 400,000 acre-feet of recharge.

Stephanie Anagnoson, director of water and natural resources for Madera County, concurred with Reiter’s assessment that incentives are key—and she also stressed the importance of groundwater accounting. “Because we have allocations and a groundwater accounting system,” she said, “we had people who were very eager to take water.” Anagnoson said she’d like to see more districts embrace the idea of a water budget and an allocation and accounting system. “Everybody needs to be on allocations; it’s how you manage your water.”

Growing familiarity with the practice helped, too. “People used to think recharge could only be done on grapes, but now people are doing it on […]

Full article: www.ppic.org