The Great Salt Lake, Utah’s largest saline lake, is an ecosystem of significant ecological and economic value. This vast body of water supports diverse wildlife and industries. However, the lake is shrinking at an accelerating rate, causing widespread concern.
Understanding the Great Salt Lake’s Decline
The Great Salt Lake has experienced fluctuations throughout its history, but recent trends show a sustained decline. Historically, the lake’s average surface elevation was around 4,200 feet above sea level. After reaching a record high of 4,211.6 feet in 1986, its water levels steadily dropped.
The lake hit new historic lows in recent years, falling to 4,190.1 feet in July 2022 and 4,188.5 feet by November 2022. This reduction has exposed over 800 square miles of lakebed, an area comparable to Maui. Over the past three decades, the lake has lost more than 15 billion cubic yards of water, shrinking at about 4 inches per year. This desiccation has resulted in the lake losing an estimated 73% of its water and 60% of its surface area, with shorelines receding up to 20 miles.
Primary Factors Driving Desiccation
The Great Salt Lake’s decline stems from extensive human water diversions and the impacts of climate change. A significant portion of river water that would naturally flow into the lake is diverted for human uses. Approximately 62% of the inflow is diverted before reaching the lake, with agriculture accounting for nearly 75% of this diversion, primarily for irrigating crops like alfalfa and hay.
Municipal and industrial sectors make up about 25% of the diverted water in the Great Salt Lake Basin, largely for residential and commercial landscape irrigation. These human activities are responsible for 67% to 73% of the current lake-level decline, causing an 11-foot drop in the lake’s elevation. Consistent diversion from the Bear, Weber, and Jordan rivers, the main tributaries, prevents the lake from replenishing its volume. This human intervention has altered the lake’s natural state.
Climate change also exacerbates the lake’s decline. Northern Utah has experienced a temperature increase of about 4°F since 1900, intensifying drought conditions. This warming leads to reduced snowpack and increased evaporation from the lake’s surface, diminishing water levels. While human water consumption is the dominant factor, climate change accounts for about 9% of the lake’s decline by reducing runoff and increasing evaporation.
Widespread Consequences of a Shrinking Lake
The Great Salt Lake’s desiccation impacts the region’s ecology, public health, and economy.
Ecological Impacts
The shrinking lake threatens the habitat of millions of migratory birds. Up to 10 million birds from 350 species rely on the lake as a stopover point along the Pacific Flyway. Increasing salinity of the remaining water, a direct result of reduced volume, threatens brine shrimp populations. These shrimp are a primary food source for migratory birds, and their decline could collapse the lake’s food web and broader ecosystem.
Public Health Impacts
Exposure of vast lakebed areas leads to air quality degradation. Dried sediments contain heavy metals and toxic substances, including arsenic, mercury, and lead. Strong winds create dust storms that carry these contaminants into nearby communities. These dust events, particularly from “hot spots” like Farmington and Bear River Bays, can worsen respiratory conditions and contribute to heart and lung diseases. Dried lakebed portions also released about 4.1 million tons of carbon dioxide and other greenhouse gases in 2020.
Economic Impacts
The lake’s decline affects several industries. The brine shrimp harvesting industry, supplying 45% of the world’s brine shrimp eggs, faces challenges as increasing salinity impacts reproduction and requires costly dredging. This industry could face annual losses of $67 million. Mineral extraction operations, producing salt, magnesium, and potash, also depend on lake levels. The lake supplies 100% of U.S. primary magnesium production and 14% globally. Tourism and recreation, including boating and bird watching, are impacted by low water levels, with potential annual losses from $33.8 million to $81.9 million for recreation and up to $9.6 million for ski resorts. The lake’s overall economic value is estimated between $1.32 billion and $1.9 billion per year.
Efforts Towards Preservation and Recovery
Addressing the Great Salt Lake’s decline involves a multi-faceted approach, focusing on water conservation, policy changes, and scientific research.
Water Conservation
Water conservation initiatives reduce demand on the lake’s water sources. Proposals suggest reducing upstream water consumption by 35% to stabilize and refill the lake. Programs incentivizing water-wise landscaping, like turf buyback initiatives, and structured water rates encourage efficient water use by municipalities and residents.
Policy Changes
Policy changes are underway to manage water resources. In 2023, the Office of the Great Salt Lake Commissioner was established to coordinate strategic planning and collaboration. The governor suspended new water appropriations within the Great Salt Lake Basin in November 2022, with exceptions for projects that include mitigation plans. New water distribution plans for mineral extraction companies tie water usage to lake levels and incentivize water direction to the lake. The Great Salt Lake Watershed Enhancement Trust, founded in 2023, facilitates voluntary water transactions to improve water flows and restore wetlands, having secured 68,000 acre-feet of water.
Scientific Research
Scientific research informs conservation and management strategies. The Great Salt Lake Strike Team, a collaboration of academic and state experts, provides data and insights to decision-makers. Ongoing monitoring of air quality, groundwater levels, and stream flow provides data for informed decision-making. New technologies, such as telemetry systems, measure water flow into and out of the lake. Researchers are also exploring hidden underground water systems, or “oases,” that contribute fresh water, seeking to understand their role in the lake’s hydrology.