Some northern Utah irrigators will see their water deliveries reduced this summer thanks to a skimpy snowpack that has left many reservoirs only two-thirds full at the peak of runoff season.
The Weber Basin Water Conservancy District board last week approved a 20 percent reduction in deliveries starting immediately. The board also voted to end irrigation season two weeks early on Oct. 1 and to ask retail customers to voluntarily reduce their outdoor water use by 20 percent.
“Along the Wasatch Front we were above normal snowfall levels” during the winter, said Scott Paxman, Weber Basin assistant general manager. “But storms moved in a north-south direction and very little of that snow got on the Wasatch Back where our reservoirs are. We only got a 70 percent snowpack.”
It wasn’t just low snowfall that reduced supply across the Wasatch, but also the way the snowpack melted, according to Brian McInerney, a National Weather Service hydrologist.
“It melted early and inefficiently,” McInerney said, referring to a heat wave in late April followed by a cold snap. Without a steady runoff, more water was absorbed into the ground and transpired through vegetation than reached the streams.
“We produced 50 percent of normal runoff in these areas,” McInerney said. “The reservoirs are expected to be half to the two-thirds full in the northern parts of the state.”
The small irrigation companies that rely on stream flows, as opposed to stored water, are also bracing for shortages.
“We are on a pressure system and a holding pond,” said Gene Bailey, president of the Liberty Irrigation Co. serving about 300 homes and several farms in the north end of the Ogden Valley. “When that fails to fill we have cut back watering a half a day or a day and half.”
The southern half of the state is in not much better shape; some areas had nearly shed their entire snowpacks by the end of April, according to last month’s water outlook report by the Natural Resources Conservation Service. Many reservoirs were expected to achieve only half their capacity.
The Weber Basin district, which manages water stored in seven reservoirs on the Weber and Ogden rivers, is wasting no time in taking steps to avoid a crisis.
Most of the 200,000 acre feet the district is contractually obligated to deliver each year goes to irrigators, but about one-third goes to residential users.
The measures announced Tuesday — the district’s first season-long irrigation cutback in 10 years — are expected to reduce overall deliveries by 7.5 percent.
“This is a precautionary measure,” Paxman said. “We are not touching culinary contracts yet. We don’t believe we will be out of water, but we are looking to next year also. We want to save as much this year for next year’s use.”
While residential conservation measures are voluntary, some watering restrictions are mandatory. Homeowners may not water their yards between 10 a.m. and 6 p.m. or use “excessive” amounts. Those who fail to comply risk losing secondary water service for the season.