The U.S. Bureau of Reclamation announced Friday, March 22, that farm water districts south of the Sacramento-San Joaquin Delta would only get 20 percent of their contracted allocations from the federal Central Valley Project water system. A Feb. 25 announcement estimated those district would get 25 percent of their contracted supply.
Even in a relatively wet year, it is typical for supplies to be below 100 percent for West Side farmers, who are among the first in the state to have their supplies cut if there are restrictions on how much water is pumped through the Delta-Mendota from the Delta.
According to David Murillo, the U.S. Bureau of Reclamation’s Mid Pacific regional director, the most recent curtailment results from sparse rain and snowfall, which will cause as runoff from the Sierra snowpack to be less than usual.
In addition, bureau officials expect there will be less water in reservoirs this summer and some other water will be lost as the bureau meets state mandates to push fresh water through the Delta to address salinity issues.
Despite the challenges, the reclamation bureau is looking for opportunities to enhance water supplies through water transfers, exchange programs and other arrangements, Murillo said.
“We are exploring all options to assist in alleviating the serious impacts of these drought conditions,” he said.
No shortage of challenges
Following an extremely wet December, the rains mostly came to a halt in January.
Meanwhile, the Sierra snowpack, which provides runoff that feeds into the Delta and is pumped into the Central Valley Project, was 54 percent of normal as of Tuesday, March 26, according to the state Department of Water Resources.
Irrigation districts also lost 15 percent of their annual supply this year because of restrictions to water pumping from the Delta in efforts to preserve the Delta smelt, an inch-long endangered fish, according to local irrigation district representatives.
A total of 256 adult smelt have been killed at a federal pumping plant near Tracy since late last year, according to U.S. Fish and Wildlife Service officials. Biologists say the fish is an “indicator species,” meaning its well-being is reflective of the overall health of the Delta.
While operators at the plant turned off four of five pumps Feb. 8 to comply with a mandate from the U.S. Fish and Wildlife Service, restrictions have since been eased. On Tuesday, March 26, three of the pumps were operational, but that has not made up for the early cutbacks.
Feds seek alternative sources
The Yuba County Water Agency has agreed to provide extra water to federal Central Valley Project contractors, and an “intertie project” uses a new pump station near Tracy to transfer water between the state-run California Aqueduct to the Delta-Mendota Canal. Neither effort has staved off cutbacks, however.
The bureau has outlined several other alternative sources in a water plan updated this month.
For instance, the bureau could store some Central Valley Project water intended for San Joaquin River Exchange Contractors, who could receive additional water deliveries during periods of high water demand. The exchange contractors, which are based in Merced and Fresno counties, agreed in the 1930s to trade off their rights to draw from the San Joaquin and Kings rivers for guaranteed deliveries of “substitute” water from the Delta-Mendota Canal and other federal facilities. As a result, they are guaranteed most of their allocations, even in dry years.
Regulators also may consider using alternative sources to meet wildlife refuge water requirements, such as that Los Banos-based Grasslands Water District where wells were recently dug, rather than solely depending on water from the Central Valley Project.
Water district concerns
The reductions in water supply could pinch local farmers.
Many growers who receive water from the Del Puerto Water District, which receives all of its normal water supply from the Delta-Mendota Canal, already were making plans to cut back plantings when officials announced the 25 percent allocations.
Bill Harrison, general manager of the district, was out of the office this week, but said in February the district likely would seek to alternative water supplies, though they might come at a hefty price.
Even some water districts that have rights to pull water from the San Joaquin River, such as the West Stanislaus Irrigation District and Patterson Irrigation District, will be affected.
Bobby Pierce, general manager of the Westley-based West Stanislaus Irrigation District, indicated river water might not always be reliable this year due to dry conditions.
“With current hydrology in the southern Sierras at roughly 70 percent of average for this time of year,” Pierce wrote, “it will be difficult for the district to divert from the San Joaquin River at peak demand periods, thereby increasing the importance for a reliable water supply from the Delta-Mendota Canal.”
Reclamation officials say they are doing what they can to ensure a stable supply for CVP contractors, though time might be running out for this year.
Typically, the reclamation bureau issues its final allocation in May. But major rainfall could change allocations, bureau spokesman Pete Lucero said. In addition, he said no changes may be made to allocations if they are unwarranted.
“What we’re looking at is the snow melt,” Lucero said. “By the time we reach May, the snow melt has all come down.”
• Jonathan Partridge can be reached at 892-6187, ext. 26, or email@example.com.