Water users in the Roza Irrigation District and other junior rights holders will have to be more careful with the water they have this summer.
The U.S. Bureau of Reclamation’s monthly forecast issued Thursday shows junior rights water users will get 74 percent of their entitlements between now and Sept. 30. It’s about a percentage point below May’s forecast, which showed junior water rights users getting three-quarters of their entitlements.
“Most years are better than this year,” said Chris Lynch, a hydraulic engineer with the bureau’s Yakima Field Office.
For junior water rights holders, such as the Roza, it means their allotment of water is reduced, while senior rights holders — those who claimed a right to use water prior to May 10, 1905 — receive their full entitlement.
“For water users, they need to be a little more judicious in how they use their water. Run a few more sets and a few less sprinklers,” said Wayne Sonnichsen, Roza’s engineering manager. He said Roza has started rationing water in the system, limiting users to 3.3 gallons per minute per acre.
He does not anticipate Roza shutting down its system for a couple of weeks to conserve water, as it did in 2015 when a drought pushed junior users’ allotment to 47 percent.
“We wouldn’t consider shutting it off until we get to the 65 percent situation,” Sonnichsen said.
Lynch, with the Bureau of Reclamation, attributed the situation to a combination of below-normal reservoir levels at the start of the water year in October, reduced winter runoff during the winter and below-average snowfall in the mountains that has already melted off. He said the area’s total capacity is at 81 percent of normal.
While the Yakima Valley experienced a blizzard earlier this year that killed almost 2,000 dairy cows in the Lower Valley, the storms did not drop as much snow in the mountains, where it would feed the reservoirs, such as Rimrock and Bumping lakes, Lynch said.
Gov. Jay Inslee has declared a drought emergency for nearly half of Washington state, including the Lower Yakima and Naches river basins.