Responding to California’s extreme drought, state water regulators have ordered many farmers, agricultural water districts and cities to stop diverting water from rivers and streams along the San Joaquin River.
Starting Wednesday, the State Water Resources Control Board is making “significant, very deep cuts” for water users, primarily in the San Joaquin River watershed, said Erik Ekdahl, deputy director of the state water board’s water rights division.
In all, 4,571 water rights and claims are being curtailed in the Sacramento-San Joaquin Delta watershed, affecting more than 2,000 water rights holders, state officials said. That includes 212 public water systems that supply drinking water, among them San Francisco, as well as a list of large agricultural irrigation districts and hundreds of individual farmers.
The state sent curtailment notices to a larger group of about 4,500 water rights holders in August. Records show that’s out of a total of more than 16,000 water rights holders.
The latest curtailments affect water supplies of the San Francisco Public Utilities Commission as well as East Bay Municipal Utility District and other municipal suppliers. Others with supplies being cut include agricultural water districts such as Merced Irrigation District, Oakdale Irrigation District, Turlock Irrigation District and El Dorado Irrigation District, according to state records.
San Francisco’s affected water rights are on the Tuolumne River and have been used since before 1914. The San Francisco Public Utilities Commission relies on the Tuolumne River for 85% of its supplies; the rest comes from local supplies in the Bay Area.
“Our main drinking water reservoir on the Tuolumne, the Hetch Hetchy Reservoir, is full, as is Cherry Reservoir,” said Joseph Sweiss, a spokesperson for SFPUC. “To date, we have called for an 11% reduction in demand in our 2.7 million customer service area overall as our primary drought response.”
The last three years have been some of the driest on record in California, and scientific research shows global warming has been intensifying the extreme aridity throughout the West over the last 22 years.
According to the state water board, the curtailments will reduce diversions by about 443,000 acre-feet during June — which for comparison is nearly 90% of the average annual water use in Los Angeles.
State records show that 3,349 water rights are being curtailed in the San Joaquin watershed, while an additional 1,222 rights are being cut in portions of the Sacramento River watershed, including along Bear Creek, Cache Creek and Putah Creek, among others.
Some of the entities with large numbers of rights curtailed include the Sierra National Forest, Stanislaus National Forest and other public lands, as well as Pacific Gas & Electric Co.
California’s water rights system allows for regulators to curtail rights and halt diversions based on the year that a right holder started using water. The latest cuts affect many lower-priority junior water rights, but some with senior rights dating to the early 1900s are also affected.
“In the San Joaquin, we anticipate that the curtailments will go down as far as 1900 in terms of priority, with some subwatersheds in the 1910s to 1920s,” Ekdahl said Tuesday during a state water board meeting. “In the Sacramento watershed, we actually don’t anticipate significant curtailments at this time,” with the exception of some smaller tributaries.
Large quantities of water are typically diverted to supply vast farmlands growing almonds, pistachios, grapes, alfalfa for cattle and other crops. Water deliveries for agriculture have already been cut back substantially during the drought, forcing growers to leave some lands dry or pump more groundwater, which has been rapidly declining in many areas.
The latest curtailments will have major effects in farming areas, said Danny Merkley, director of water resources for the California Farm Bureau.
“It’s a big impact, and it’s a big impact on all those communities that rely on it,” Merkley said. He said given the current situation, the curtailments were inevitable. The state water board’s members, he said, are “dealing with the hand that’s been dealt with them, with the other priorities that the state has put on water.”
Merkley said he hopes the cuts don’t lead to food shortages or significant hikes in food prices, “because I really do not want to rely on China or Mexico or South America for my food supply.”
He said the cutbacks show California should move more quickly on projects to store water, including the proposed Sites Reservoir project, as well as projects to capture water during wet years to recharge groundwater aquifers.
On Friday, under a separate order, Ekdahl said, an additional 125 water users in the Sacramento-San Joaquin watershed were told to stop diverting water.
The state water board on Tuesday also approved an agreement that allows those who have water rights along the Upper Russian River to voluntarily use less water and share the water they have available. Sam Boland-Brien, a supervising engineer with the state board, praised the cooperation that made the deal possible, saying it “shows what can be accomplished when state and local entities work together to come up with solutions.”