Utah enjoys its deepest snowpack in years, but water officials are not quite ready to declare an end to the drought

Ken’s Lake in Grand County is barely a puddle of its normal self, currently holding just 20 percent of its 13,000 acre-foot capacity, thanks to seven straight dry years in southern Utah.

The level of this reservoir near Moab is expected to dramatically rise in the coming weeks as the La Sal Mountains sheds a snowpack that is holding twice as much water as it usually does this time of year.

“It’s official: Utah’s snowpack is fantastic this year!” federal hydrologists crowed in a water report released Thursday. “Statewide, this snowpack ranks substantially better than 2017, and almost as good as the banner years of 2005 and 2011. While the whole state is doing quite well, southern Utah is having a particularly excellent winter.”

The water stored in the snowpacks of San Juan, Grand and eastern Uintah counties is 207 percent of normal as of Thursday, while it is 191 percent for southwestern Utah, according to the Natural Resources Conservation Service, or NRCS.

Barely six months ago, Utah was in a drought emergency, coming after the driest, second-warmest year on record, which was particularly hard on southeast Utah. In hindsight, Gov. Gary Herbert’s official drought declaration on Oct. 15 seems to have wakened the rain gods.

Consistent precipitation has been falling across the state ever since, building up snowpacks across Utah’s 15 hydrologic basins, which collectively stand at 140 percent of the 30-year mean, promising to fill depleted reservoirs and bring relief to southern Utah ranchers and farmers stressed by persistent drought.

(Christopher Cherrington | The Salt Lake Tribune)

The repeat storms had the added benefit of improving Utah’s air quality by repeatedly breaking up the inversions that trap pollution in the valleys.

Meanwhile, the snowpack is still growing, and that could spell trouble if rain and hot temperatures trigger a chaotic runoff later this spring.

“If it keeps going like this and cold and wet through April, it will keep adding to high elevation snowpack, and we’ll have a runoff like we had in 2011. We will see some loss in the lower elevations, and that might be a good thing because that will free up some room to mitigate that flooding risk,” said Troy Brosten, the NRCS hydrologist who supervises the water supply outlook reports. “It’s a double-edged sword because now we will worry about flooding, but there are a lot of reservoirs that really need the water.”

These monthly reports are based on data generated from 96 “Snotel” monitoring stations scattered around Utah’s mountain ranges, sited to give a representative snapshot of the state’s seasonal water supply. Each Snotel, a contraction of the term snow telemetry, is equipment with instruments that record snow depth, water equivalence, air temperature, precipitation and soil moisture at depths of 2, 8 and 20 inches.

The lowest snowpack is on the Uinta Mountains’ north slope, drained by the Bear River, which is barely above normal. The Central Wasatch snowpack, which feeds Utah’s urban core, is 142 percent of the 30-year average.

The La Sals Snotel station, located at 9,578 feet above sea level, indicates 21.5 inches of water equivalent in its snowpack, a huge leap from the 10 inches it achieved last year at its peak.

The Grand Water & Sewer Service Agency, which operates Ken’s Lake at the foot of the La Sals, anticipates robust runoff.

“We hope the temperatures stay cool and the runoff comes down at a steady rate. A steady runoff ensures dam safety by not filling the lake too quickly,” said agency manager Dana Van Horn. “We hope the runoff will supply the lake with enough water for this season and some in storage for next year.”

Statewide, reservoirs are standing at 65 percent of capacity, down from 77 percent at this time last year. Thursday’s report predicts that most of the small- to medium-size reservoirs will completely fill and the larger reservoirs should see a substantial improvement.

Down 135 feet from its peak level, Lake Powell, the state’s largest reservoir and farthest downstream on the Colorado River, is not expected to fully rebound.

This winter was ideal for several reasons in addition to large amounts of snowfall, according to Jon Meyer, a research climatologists with the Utah Climate Center.

“Unlike the recent years, there hasn’t been a split in the state’s snowpack picture where parts of the state miss out while others enjoy a better winter. This year it’s been all good news; just in time, thankfully, following the dire water year we had last year,” Meyer said. “If we could order up a season like we’ve had this year, I can’t think of a better order to place.”

But Meyer is waiting to see how the spring runoff plays out before he crowns 2018-19 the perfect water year.

Soil moisture levels are down in some areas, which could make for a less efficient runoff, according to Brosten. This is because it would take more water to saturate soil before it can run into streams.

And if the snowpack melts rapidly, as it did in 1983, streams could overflow their banks and that water might not even reach a reservoir, warned Rachel Shilton, section manager for river basin planning for the Utah Division of Water Resources.

Utah water honchos like Shilton aren’t ready to declare an end to the drought, although they remain “cautiously optimistic.”

“There is talk about that, but when we talk with the farmers, the boots on the ground, they are pretty cautious,” Shilton said. “One good year doesn’t mean rejuvenation of their fields and livestock. I don’t want to promote that because I want them to still be conscientious about their water use. We still want to have that water-wise ethic.”