FRESNO  (AP) — A group of public water agencies that serves millions of Californians asked the state on Tuesday to order farmers in the Sacramento-San Joaquin River Delta to stop irrigating their crops amid the relentless drought.

The State Water Contractors, which has 27 members that include the Metropolitan Water District of Southern California, filed a complaint with state officials, accusing some Delta farmers of illegally using water that the public agencies have stored in reservoirs. The agencies say they are forced to release water from the reservoirs to prevent salty bay water from intruding into the Delta.

“We’re depending on stored water to meet environmental needs,” said Stefanie Morris, acting general manager of the State Water Contractors. “Keeping the Delta water fresh this summer will be like trying to fill a bucket with a hole in the bottom.”

The water agencies provide water to 26 million residents from the San Francisco Bay area to Southern California and 750,000 areas of farmland through a vast system of canals and reservoirs. The public water agencies say they have provided proof to the State Water Resources Control Board showing farmers last year took in excess of their legal right an amount equaling the water needed to serve more than 2 million people for one year.

Cutbacks from drought and other environmental standards allowed State Water Contractors this year to send its customers 20 percent of their contracted allocations, requiring its members to draw down other supplies, the association said.

The state water board will next decide whether to investigate the complaint. George Kostyrko, a spokesman for the state water board, declined to comment.

In its fourth drought year, cities and businesses are being required to cut their water use by a quarter, and thousands of farmers have been ordered to stop irrigating from rivers, including some farmers with near iron-clad rights.

John Herrick, manager of the South Delta Water Agency, said farmers he represents in the Delta south of the San Joaquin River have every right to the water. Because the Delta is connected to the San Francisco Bay, Herrick said there is always water available for farmers to use. He said it is not breaking the law for farmers there to use lower-quality water.

“They’re just factually incorrect,” Herrick said of the complaint. “Even if the rivers got down to nothing, we still have water.”