The Great Salt Lake, the largest saltwater lake in the Western Hemisphere, is shrinking at a dramatic pace. This terminal lake in Utah is a significant ecological and economic engine currently facing an unprecedented crisis. Its decline represents a profound shift in one of the American West’s most recognizable natural features. This urgent situation has drawn attention due to the substantial risks associated with its continued desiccation.
The Evidence of Decline Quantifying the Loss
The crisis is confirmed by decades of quantifiable data showing a substantial reduction in water levels and volume. The lake hit its historic low in November 2022, when its average daily water elevation dropped to 4,188.5 feet above sea level. This is far below its historic average of approximately 4,200 feet.
This drop translates to an immense loss of water volume, estimated to be around 73% of its historical content. Because the lake is extremely shallow, a small decline in elevation results in massive exposure of the lakebed. The surface area has shrunk by about 60% from its historical high, reducing its footprint from approximately 3,300 square miles to around 950 square miles in 2022.
Primary Drivers of Water Depletion
The severe depletion of the Great Salt Lake results from a combination of human activity and intensifying climate factors. The largest single driver is the diversion of water from the rivers and streams that feed the lake. Upstream water consumption is responsible for an estimated two-thirds of the lake’s overall decline.
The vast majority of this diverted water, up to 82% of Utah’s total water use, is allocated to agriculture. This water is primarily used for irrigating water-intensive crops like alfalfa and hay. These diversions prevent streamflow from the Bear, Weber, and Jordan rivers from replenishing the lake, which is necessary to balance natural evaporation.
Climate factors, particularly drought and increased temperatures, are accelerating the problem. The remaining loss, not accounted for by reduced streamflow, is attributed to increased evaporation. Warmer air and water temperatures cause more water to escape directly from the lake’s surface into the atmosphere. Because the lake’s surface area is vast, even small increases in air temperature lead to significant water loss.
Environmental and Health Ramifications
The shrinkage has profound effects on the regional ecosystem and poses a direct threat to public health. Ecologically, the most immediate consequence is the skyrocketing salinity levels in the remaining water, which threatens the lake’s keystone species: the brine shrimp. These crustaceans form the base of the lake’s food web and are harvested for a multi-million dollar industry, but they cannot survive in hypersaline conditions.
The lake is a globally recognized stopover point for up to ten million migratory birds, including phalaropes and avocets, which rely on the brine shrimp and brine flies for food. The loss of this habitat due to low water levels and increased salinity puts these bird populations at risk.
The exposure of the lakebed, often called the “playa,” is the most significant public health concern. This newly exposed lakebed contains a high concentration of toxic elements, including arsenic, mercury, and lead. As the playa dries, wind events can pick up this fine sediment and carry it as airborne dust across the Wasatch Front. This toxic dust threatens the air quality for the 1.2 million residents in the nearby Salt Lake City metro region, increasing the risk of respiratory illnesses and heart disease.
State and Local Response Measures
In response to the crisis, state and local authorities have begun implementing measures focused on water conservation and efficiency. The Utah legislature has dedicated substantial funding, including a $200 million appropriation, toward agricultural water optimization projects. These efforts aim to help farmers adopt more efficient irrigation technologies that use less water while maintaining crop yields.
A significant shift in water policy occurred with legislation that altered the state’s historic “use it or lose it” water rights doctrine. This change allows water right holders, particularly in agriculture, to conserve water without fear of forfeiting their rights, providing a direct incentive to leave more water in the rivers. Industrial users have also committed to conservation, with companies like Compass Minerals and Morton Salt agreeing to forgo hundreds of thousands of acre-feet of future water use.
A dedicated Great Salt Lake Strike Team, composed of policy and scientific experts, has been established to provide data-informed guidance to state policymakers. This team supports efforts to increase water flow, which has included voluntary water donations and releases from reservoirs, such as approximately 10,000 acre-feet from Utah Lake via the Jordan River. These actions represent a growing recognition that coordinated, multi-sector efforts are necessary to stabilize the lake’s elevation.