Great Salt Lake, Utah: record-low level on 7 November 2022 and the attribution of the decline

The US Geological Survey (USGS) states that on 7 November 2022 the southern arm of the Great Salt Lake had receded to a record low water surface elevation of 4,188.5 feet above NGVD 1929, "after years of much lower-than-average precipitation". USGS gives the lake's area as approximately 2,300 square miles in 1986, when the lake was at a record high, and "less than 1,000 square miles" in 2022. The State of Utah's Great Salt Lake site gives the 1986 record high as 4,211.65 feet with a surface of about 3,300 square miles, and says the lake covered roughly 800 square miles at the November 2022 low. The Utah Division of Wildlife Resources (DWR) page states that between 1875 and the lowest level it lists (4,191.35 feet) the lake dropped about 8.5 feet from a historic high of 4,211.6 feet, which "resulted in a loss of about 44% of the lake's surface area"; that page does not mention the 2022 record.

The lake has since stood above that record. A Salt Lake Tribune article of 7 January 2026 put the southern end at 4,191.6 feet, with the north arm about half a foot lower, about 800 square miles of lakebed exposed and salinity at around 12%, against about 16% at the January 2022 elevation (4,190.4 feet), according to Bonnie Baxter of Westminster University. KUER reported the lake at about 4,190 feet in early August 2026, about eight feet below the minimum target range in the 2024 strategic plan. DWR's page showed 4,189.8 feet at Saltair Boat Harbor on 26 October 2026.

Wurtsbaugh and seven co-authors (Nature Geoscience, 23 October 2017) report that "there has been no significant long-term change in precipitation or streamflow from mountain tributaries" since 1847, while "water development and river diversions since 1847 have produced a persistent reduction of flow into the lake, approaching 40% in recent years", and that lake area has shrunk about 50%. Their water-balance model, run without consumptive uses, gives a flat long-term trend at a natural mean elevation of 1,282 m (4,206 feet). The text states that water consumption is responsible for an observed lowering of approximately 3.4 m (11 feet) and a reduction in lake volume of 48%; the caption of their Figure 3 gives 3.6 m. The paper also records the lake's lowest level at that time in November 2016 and says climate change "does indeed represent a pervasive long-term problem" for saline lakes.

Other bodies give other attributions. The Great Salt Lake Strike Team (Utah State University, the University of Utah and the Utah Departments of Natural Resources, Agriculture and Food, and Environmental Quality) wrote on 8 February 2023 that "Human and natural consumptive water use explain over two-thirds of low lake levels", estimating the contribution to the current record-low elevation at 67-73% for natural and human consumptive use, 15-23% for natural variability and 8-11% for direct evaporation from climate warming. USGS Circular 913 (1984) states that the lake "would have been about 5 feet higher in 1983 had there been no consumptive use of water owing to man's activities in the lake basin since 1847". The DWR page states: "In fact, it is estimated that the lake is 11 feet lower due to human diversions." In the lawsuit filed in 2023 the plaintiffs allege that upstream diversions are "by far the most significant cause" of the decline; the court's ruling of 27 March 2025 recorded the allegation and did not decide causation.

On who used the water, Wurtsbaugh et al. cite state evaluations of total consumptive use of approximately 1.8 billion m3, composed of agriculture (63%), lake water extraction for salt-pond mineral production (13%), municipal and industrial uses (11%), evapotranspiration from constructed wetlands (10%) and reservoir evaporation (3%). The New York Review of Books, citing a 2025 study, reported that alfalfa in the basin accounts for about 56 percent of water depletions but only 0.07 percent of Utah's GDP. The Salt Lake Tribune reported in September 2024 that mineral companies "deplete about 7% of its water"; the two shares have different bases and the sources do not reconcile them. The State of Utah says the lake contributes more than $2 billion to the state's economy annually; Wurtsbaugh et al. cite a 2012 estimate of US$1.32 billion per year from mineral extraction, brine shrimp cyst production and recreation.