California Farms Dried Up a River for Months. Nobody Stopped Them.

During California’s most recent drought, officials went to great lengths to safeguard water supplies, issuing emergency regulations to curb use by thousands of farms, utilities and irrigation districts.

It still wasn’t enough to prevent growers in the state’s agricultural heartland from draining dry several miles of a major river for almost four months in 2022, in a previously unreported episode that raises questions about California’s ability to monitor and manage its water amid worsening droughts.

It’s not uncommon, during dry spells, for farmers and other water users in California to draw streams down to a trickle in places. But the severity and duration of the 2022 decline of the river in this case, the Merced, where one stream gauge showed zero water moving past it nearly every day from June to early October, stood out even to experts.

“I was very surprised to see a river of this size without water,” said Jon Ambrose, a biologist with the National Oceanic and Atmospheric Administration’s fisheries service who visited the Merced’s parched riverbed that August. “This just isn’t something we see. This isn’t something that should be seen as normal.”

The Merced River originates in Yosemite National Park. It rushes through glacier-carved canyons and winds for about 60 miles through the Central Valley before pouring into the San Joaquin River, which nourishes the valley’s southern half.