In summary

State officials warn some of the state’s most powerful and largest agricultural districts that their plans fail to address how over-pumping could harm local communities’ drinking water supplies.

The state’s water agency today lambasted groundwater plans drafted by some of California’s largest and most powerful agricultural water suppliers in the San Joaquin Valley, indicating that they fail to protect drinking water supplies from over-pumping.

The four large groundwater basins at stake underlie stretches of San Joaquin, Merced, Madera and Fresno counties that are home to nearly 800,000 people and more than a million acres of irrigated agriculture.

The letters sent by the state Department of Water Resources to the local districts that manage the basins have a common theme: a failure to address how pumping, largely for growers, will harm the drinking water supplies of local communities. “That, in some plans, missed the mark,” said Paul Gosselin, deputy director of sustainable groundwater management at the California Department of Water Resources.

“As we sit here in this drought, the need and the promise to make sustainable groundwater management fulfill its mission and promise couldn’t be more important,” Gosselin said.

One of the districts with a plan criticized by the state is the powerful Westlands Water District, the largest agricultural water agency in the nation. It provides water to more than 1,000 square miles of prime farmland in western Fresno and Kings Counties.

A main threat in the San Joaquin Valley’s Westside subbasin, managed by the Westlands Water District, is subsidence: the risk that land could continue to sink when groundwater is pumped. In addition, the state warned that water quality could suffer in parts of the basin.

Shelley Cartwright, a spokesperson for Westlands, said the water district looks forward to reviewing the department’s preliminary findings. She said the plan “ensures groundwater levels stay at or above 2015 levels” and “avoids undesirable results and ensures the beneficial users of groundwater, such as local communities, are not harmed.”

Low-income Latino communities are especially hard hit by well outages in agricultural areas.

Groundwater is the primary source of drinking water for most of the state’s more than 7,400 public water systems, and 6 million people depend on it entirely. The biggest user is agriculture, which taps into about 80% of the groundwater pumped in the state.

It’s a finite resource overdrawn by about 2.5 million acre-feet per year. And supplies are strained even further in dry times.

The problem is especially acute in the San Joaquin and Central Valleys. According to one study, groundwater depletion poses the greatest threat to the San Joaquin Valley’s domestic wells. Another tallied up to 12,000 drinking water wells that could go partially or completely dry by 2040 under the groundwater plans drafted in the region.

Low-income Latino communities are especially hard-hit by well outages.

In response to the thousands of wells going dry during the last drought, the California Legislature enacted a package of laws that became the Sustainable Groundwater Management Act, aimed at slowing the race to deplete California’s aquifers.

Now, seven years later, drought has gripped California once again. Residents have reported more than 950 dry wells already this year — a 1,024% increase over last year.

Under the law, local groundwater districts in the most depleted basins were required by January 2020 to submit plans to reduce over-pumping to sustainable levels over the next 20 years. The state agency’s final assessment of the plans is due in January 2022, but agencies can start implementing them as soon as they’ve adopted them.

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