Will December’s big storms make a difference for the Great Salt Lake?

The state’s snowpack is off to a good start, but the lake will need a lot more to recover.

(Trent Nelson | The Salt Lake Tribune) Dust blows through Antelope Island and the Great Salt Lake on Saturday, June 18, 2022.

After several disappointing years in a row, this winter’s snowpack to date has a lot of Utahns feeling optimistic. But whether it’ll be enough to bring the Great Salt Lake back from the brink remains to be seen.

After hitting a record-low elevation for two years in a row, the lake needs all the water it can get. Rising salinity levels have stressed the ecosystem that millions of migratory birds depend on each year. Mineral companies are having a hard time accessing the brine they need, and brine shrimp companies might not have a harvest next year if something doesn’t change.

There is a reason for optimism — all the watersheds that feed the Great Salt Lake currently have snowpack that’s above average, thanks to some early-season storms and a hefty helping of powder that fell last week. Those storms will need to keep coming all winter, however, for the lake to reverse its collapse.

“This is like having the lead in the first of half of a football game,” said Jim Steenburgh, professor of atmospheric science at the University of Utah. “... We have to hope it keeps continuing.”

For the lake to rise, its rivers will need a surge of snowmelt

The lake’s “Goldilocks zone” for a healthy elevation is around 4,200 feet — about 11 feet higher than its current level. But if the lake climbs to at least 4,195 feet, it would reach a point “where most resources are not significantly compromised,” according to information provided by the Utah Department of Natural Resources.

It would take about five years of average snowpack for the lake to rise to that target elevation, the department’s models show.

But if Utah sees epic snowfall, on par with the 2016-2017 season, it would take only two years for the lake to reach 4,195 feet.

Runoff in 2017 brought 3.2 million acre-feet to the Great Salt Lake, compared to about 2 million acre-feet it sees in a normal year. The winters that followed were much drier, however, which continued to fuel the lake’s long-term rate of decline. Only about 1.2 million acre-feet reached the Great Salt Lake in both 2021 and 2022, according to the Department of Natural Resources.

The Great Salt Lake is a terminal lake, which means water only leaves it through evaporation. But given its massive surface area, that water output is extensive — it loses about 2 million acre-feet a year.

Did the latest storms raise the lake’s elevation at all?

While December’s storms may have felt epic to skiers and snowboarders, they haven’t done much to help the lake so far.

A U.S. Geological Survey gauge on the south side of the lake’s railroad causeway shows its elevation has only risen slightly since bottoming out in November. It’s still about two feet lower than it was at this time last year.

(U.S. Geological Survey website) A screen capture of real-time data beamed from a gauge on the south side of the Great Salt Lake's causeway shows how the lake's elevation over the past year compared to 2021. Snowstorms in December put Utah's snowpack statewide well above average, but have done little to raise the lake level so far.

That doesn’t mean storms play an insignificant role in sustaining the Great Salt Lake until snowmelt season. Because it’s so large, about one-third of the lake’s water input each year comes from direct precipitation.

In 2021, about 573,000 acre-feet fell over the Great Salt Lake in the form of rain or snow, according to the Division of Water Resources. This year it saw about 464,000 acre-feet from direct precipitation.

The current state of snowpack in the Great Salt Lake basin

The lake’s tributary rivers account for about 65% of its input, which means its fate is largely tied to what happens with runoff in the spring.

And all the Great Salt Lake’s tributary watersheds are off to a good start so far.

The Bear River basin, the lake’s largest tributary, has snowpack at 138% above average for this time of year. Both the Weber River and Provo-Jordan basins are at 145% of normal.

(U.S. Natural Resources Conservation Service) Snowpack in the Great Salt Lake's watershed is well above average for this time of year, but storms will need to continue through the winter to boost the lake's elevation.

“Nobody knows where we’re going to end up” this winter, Steenburgh said, “[but] I think the odds are stacked that we’ll end up ahead.”

And it’s not just the Great Salt Lake’s tributaries that need a flurry of above-average storms. The Colorado River Basin has struggled with drought and overconsumption as well, dropping reservoirs like Lake Powell to unprecedented lows and creating tensions among the growing populations that rely on an increasingly scarce resource.

“The Great Salt Lake is obviously important,” Steenburgh said, “but all of our reservoirs are down. It would be great to have a big year for the entire state of Utah.”