As water year ends, Great Salt Lake expected to hit annual low

SALT LAKE CITY (Utah News Dispatch) — A “really good” water year came to an end this week as the Great Salt Lake likely hit its annual low, with officials expecting levels to rebound in the coming months. 

The water year, also called the hydrological year, runs from Oct. 1 to Sept. 30 — the 2025 water year started on Tuesday. It’s a way for the federal government to measure precipitation and snowpack, starting from when lake levels and stream flows are usually at their lowest, in the fall. Snow generally begins to accumulate in the fall, melting in the spring and summer and boosting lake and stream levels with runoff. The goal of a water year is to give a comprehensive measurement of that cycle. 

That’s reflected in Great Salt Lake levels, which often bottom out in October and then slowly rebound through the winter, hitting peak levels in the spring. On Wednesday, Great Salt Lake Commissioner Brian Steed said he expects the lake to hit its lowest point this week. 

“We are really looking forward to that fall precipitation, making sure we can start the recovery of the lake,” Steed said Wednesday. 

Having two good water years in a row has been a gamechanger for the beleaguered lake, which hit a historic low of 4,188.5 feet in November 2022. The lake is separated by a causeway that divides the north and south arms — as of Wednesday, the south arm was at 4,192.6 feet, and the north arm at 4,191.8 feet. 

That’s the closest the two sections of the lake have been in two years, according to state data, all thanks to a historic winter in 2023 and an above-average winter in 2024. Water managers intentionally kept water in the south arm, where the lake’s main tributaries enter, in an attempt to reduce high salinity levels. But this summer, Steed said the berm that controls the flow of water from the south arm into the north arm was left open, allowing the two sections to equalize. 

“That’s actually something that’s interesting and important to us, because we manage the lake as a whole,” he said. “Having those two good consecutive water years has actually been what facilitated that recovery.” 

But the lake still has a ways to go before it’s considered “healthy.” One bad water year could put the lake back on the verge of ecological collapse, and Steed reminded reporters on Wednesday that levels need to rise about two feet to be on the bottom end of the “healthy” spectrum. 

What should Utahns expect for the new water year? It’s a toss-up, Steed said. Some experts told him good water years come in threes, and that the upcoming winter will bring above-average precipitation — other experts point to historical tree ring data that suggests megadroughts, like the one Utah is currently in, don’t pause for long. 

“We will continue to make sure we have policy options on the table, as well as leasing options on the table, to get water to where it needs to be, in the lake,” he said, referring to two recent donations that are expected to give a boost to lake levels — an agreement with Compass Minerals that could leave up to 200,000 acre-feet in the lake, and a donation by users in the Jordan Valley Water Conservancy District to help convey about 10,000 acre-feet to the lake. 

An acre-foot is enough water to submerge an acre of land by one foot. 

“We all have to understand that we are living in a desert. And as we live in a desert, it really matters how we use our water, and people’s actions can make a difference, even if we don’t have a good water year,” Steed said. “It’s going to take a change of behavior from all Utahns in the watershed.”