Reposted from the College of Science.
In 1991, Utahns and visitors flocked to the eastern end of the Syracuse causeway-which connects Davis County to Antelope Island-waiting for the historically high water levels of Utah's Great Salt Lake to fall. Submerged under more than five feet of water in a swollen Farmington Bay, the causeway had been closed for eight years.
The water levels did fall as people hoped. But the water has since kept dropping and dropping. By 2022, the lake reached its lowest elevation on record of 4,188.5 feet above sea level. This 23-foot drop diminished the lake by 2,350 square miles, an area larger than the state of Delaware.
These days, Farmington Bay is bone dry aside from its confluence with the Jordan River to the south. Now, many Utahns are hoping-and even praying-for the Great Salt Lake to rise.
The widespread decline of terminal lakes
Terminal lakes around the world are in decline, and many have fared far worse than the Great Salt Lake. The Aral Sea in Uzbekistan and Kazakhstan was once the world's fourth-largest freshwater lake at 23,600 square miles. But during the 1950s, the Soviet Union began diverting the lake's water sources to grow cotton.
As by design, the newly irrigated fields produced high yields of cash crops, along with a sizable, but transitory economic boost to the region.
The vast lake soon lost its magnificent deep-blue color. Once home to plentiful fish and thriving wetlands, the lake has since been replaced by barren playa. The Aral Sea is so depleted that less than 10% remains today. Now, dust storms wreak havoc, Aral trout and endemic sturgeon have died off, the once fresh waters are saline, and millions of birds have either perished or moved elsewhere.
Devastating outcomes like the Aral Sea's should serve as a warning. When a natural resource is depleted to exhaustion, something else in that system collapses. University of Utah researchers from across the scientific spectrum are investigating how this warning applies to Utah's own inland sea.
Cataloguing through sedimentation
Great Salt Lake's water sources have been under pressure since Mormon pioneers began settling Utah in 1847. Gabriel Bowen's research tells a clear story of human influence on the lake. The chair of the U's Department of Geology & Geophysics, Bowen, studies the sedimentation of the Great Salt Lake, the terminal point for not only water, but solid particles (sand, mud, organic bits). His research catalogues events and land uses impacting the lake via that sedimentation.
During the mid-19th century, Mormon settlers arrived in the Salt Lake Valley via Emigration Canyon and soon planned and installed irrigation projects on a grand scale. Wetlands gave way to canals that delivered water to freshly tilled farmland. The valley that was once a desert turned green. Bowen found that around this time, an unprecedented amount of organic matter reached the lake-a clear indication of agricultural runoff.
A century later, the Union Pacific Railroad built the Lucin Cutoff, dividing the lake into the North and South arms. Prior to 1959, the sediments deposited indicate that the South Arm had an equal ratio of water evaporation to inflow-a state of equilibrium.
After 1959, two different systems emerged: a South Arm that now acts like an open system (exorheic) and a North Arm that remains a terminal lake (endorheic). As a result, the South Arm remains fresher with salinity levels today averaging 12.5%, while the North Arm is nearly three times as salty-around 33%.
Water can hold up to 360 grams of salt per liter at room temperature, less if it's colder. Currently, salt levels in the North Arm hover around 330 grams per liter. In certain parts of the North Arm, saturation levels have already been reached and halite salt crystals can be seen floating in the water.
Extreme conditions still harbor life
Great Salt Lake today is reaching a level of extreme that feels beyond extreme. It can be hard to believe that this lake can still harbor aquatic life, such as brine shrimp and brine flies. Then in 2024, U postdoctoral researcher Julie Jung and Michael Werner, assistant professor of biology, discovered a new critter: microscopic roundworms known as nematodes.
A species new to science inhabits the reef-like microbialites that cover a fifth of the lakebed. This is the most saline environment where nematodes have ever been found. A recent study by Werner's lab described the new species, dubbing it Diplolaimelloides woaabi, the Indigenous word for "worm," as a tribute to the Shoshone tribe whose ancestral lands include the lake.
The hypersaline North Arm also harbors abundant life, just not animals. Its waters are pink due to halophilic bacteria. As waters in the North Arm receded, many gypsum crystals, which can be capsules of life, were exposed. The outer layer of these crystals has been known to protect and enclose microbial ecosystems. U doctoral candidate Paulina Martinez-Koury and Westminster University professor Bonnie Baxter are investigating the organisms living inside those ecosystems. Within the minerals, they found microbes, pollens and 200 bacterial species-a testament to life's innate ability to survive. Scientists say their findings may hold clues for life on other planets, especially Mars, which was once replete with salty lakes that dried up as the Red Planet lost its atmosphere and magnetism.
Dust in the wind
The newly dried lakebed also provides opportunities for discovery, but at its core, this exposed playa is a serious environmental issue. The playa emits high levels of particulate matter PM10 and PM 2.5, the latter of which can penetrate deeply and be fully absorbed by our lungs to deleterious effect. Kevin Perry, a professor of atmospheric sciences who has surveyed dust hotspots around the lake, found that every playa soil measurement of arsenic exceeded the EPA's recommendations for routine exposure by a factor of 10.
Perry has worked alongside his colleague Derek Mallia to understand where the dust is likely to be blown. The hardest hit areas are the northwestern part of Salt Lake County and cities immediately northeast of Farmington Bay, such as Layton, Syracuse, Clearfield and Ogden, but everyone along the Wasatch Front is downwind of the lake, putting more than 2.5 million people at risk.
Perry is now trying to figure out how to prevent this dust from becoming airborne in the first place by restoring the lakebed crusts that naturally hold sediments in place. His latest research project indicates these crusts can re-form when water is applied to the unstable hotspots. Interestingly, one potential source of this water could come from below the lake itself.
The presence of phragmites on the playa suggests there is freshwater underneath feeding these invasive reeds. Geology professors Bill Johnson and Michael Zhdanov confirmed the presence of groundwater using airborne electromagnetic surveys and piezometers. Freshwater is contained within tightly packed sediments that start 30 feet below the surface and descend 10,000 feet. But more work needs to be done to determine if there is water across this entire range or just a portion.
Team Great Salt Lake
Watering the playa could be a viable temporary solution, but experts at the Great Salt Lake Strike Team have determined that the most cost-effective long-term method of lake recovery is to simply increase inflows to the lake. The Strike Team was formed in 2022 and now includes faculty from the U like biologist William Anderegg and atmospheric scientist John Lin of the Wilkes Center for Climate Science & Policy, as well as Johnson, Perry and atmospheric scientist Court Strong. Also on board are state leaders and researchers from Utah State University. Together, the team is working to combine reliable data and actionable policy to make the recovery of the Great Salt Lake a reality.
The lake's decline is more than concerning; it's an emergency underscored by an intimidating list of "what ifs." Many from the U are actively navigating this complex dilemma in search of solutions.
Bringing the lake back to its historically healthy levels of 4,198 feet above sea level will require major investment and sacrifice. But dedicating time and energy to the lake pays dividends. A stable lake means greater lake effect snow, millions of migratory birds and clean air. Additionally, taking the time to understand the lake can teach us about Utah's hydrology, extreme organisms that live within the lake, and even life on the planet of Mars, 140 million miles away. Unless we take the road of discovery and action, we might find ourselves in a predicament similar to the Aral Sea. It is clear that the true sacrifice here would be to lose our lake.
Banner image: University of Utah biologists Michael Werner, left, and Julie Jung inspect microbialite samples they collected off Antelope Island in March 2026. Jung, who discovered nematodes in the microbialites as a U postdoctoral researcher, is now an assistant professor at Weber State University. Photo credit: Dave Titensor.
The author Nathan Murthy, BS'26, Earth & Environmental Science, is an intern for the Wilkes Center for Climate Science & Policy and the College of Science, where he is a science writer. He was the selected student speaker at the 2026 College of Science convocation.
See related stories:
Airborne dust from Great Salt Lake playa has bigger impact on communities of color
The battle for breath: Controlling Great Salt Lake dust
Toxins from Great Salt Lake dust are absorbed by plants, soils and human bodies
Great Salt Lake roundworm gets Shoshone name
Freshwater under Great Salt Lake playa
