The Great Salt Lake in Utah is experiencing a severe reduction in its water levels. This decline threatens the lake’s unique ecosystem and surrounding human communities. Its diminishing size highlights a complex environmental challenge with far-reaching implications.
The Great Salt Lake’s Decline
The Great Salt Lake has undergone a profound transformation, marked by a substantial decrease in its water volume and surface area. Historically, the lake’s average elevation was about 4,200 feet above sea level, covering 1,700 square miles. In 1986, it reached a high of 4,211.65 feet, encompassing around 3,300 square miles.
However, the lake’s levels have dropped significantly in recent years. By October 2021, the elevation fell to a record low of 4,190.2 feet, surpassed in November 2022 at 4,188.5 feet. This shrinkage has exposed over 54% of the lakebed, roughly 800 square miles of dry land.
Driving Factors Behind Water Loss
The primary reasons for the Great Salt Lake’s shrinking involve a combination of human water usage and changing climatic conditions. Water diversion from the rivers that feed the lake stands as a major contributor to its decline. Agriculture accounts for a significant portion, typically between 70% and 82% of Utah’s total diverted water, primarily for irrigation. Municipal and industrial sectors collectively utilize about 25% of the diverted water within the Great Salt Lake Basin.
These diversions mean that between 2020 and 2023, the lake received less than one-third of its natural streamflow. Historically, human diversions have contributed to the lake being an estimated 11 feet lower than it would otherwise be. Climate change exacerbates the situation through prolonged drought conditions, reduced snowpack in the surrounding mountains, and increased evaporation rates due to warming temperatures.
The region’s growing population further intensifies water demand, placing additional strain on an already depleted water supply. The consistent downward trend since the 1870s has been primarily driven by these upstream water diversions. The combined effect of reduced inflow and increased evaporative loss creates a deficit that the lake cannot naturally overcome.
Far-Reaching Consequences
The desiccation of the Great Salt Lake presents a range of serious consequences that extend across ecological, public health, economic, and even meteorological domains. Ecologically, the shrinking lake poses a direct threat to its unique food web, particularly to brine shrimp and brine flies, which are foundational species. The increased salinity resulting from reduced water volume can exceed the tolerance thresholds for these organisms, leading to impacts on their reproduction and survival.
Millions of migratory birds rely on the lake and its wetlands as a vital stopover point along their flyways, and the loss of habitat and food sources endangers these populations. The exposed lakebed also contributes to significant air quality issues. Dust storms originating from the dry lakebed carry heavy metals, including arsenic, cadmium, lead, copper, and mercury, which have accumulated in the sediment over time from industrial, agricultural, and urban pollution sources. These fine particulate matter (PM2.5, PM10) can be inhaled, leading to increased risks of respiratory conditions, heart disease, lung disease, and even cancer in nearby communities.
Economically, industries dependent on the lake, such as mineral extraction (magnesium, salt) and brine shrimp harvesting, face disruptions and losses. The lake contributes an estimated $1.5 billion to $1.9 billion annually to Utah’s economy and supports thousands of jobs. Furthermore, the lake’s size influences local weather patterns, contributing to lake-effect snow in the Wasatch Mountains, which typically accounts for 5% to 10% of the snowpack. A smaller lake could diminish this effect, potentially impacting winter tourism and water resources.
Ongoing Conservation Efforts
Various initiatives and legislative actions are underway to address the declining levels of the Great Salt Lake and mitigate its impacts. Water conservation measures are being emphasized across different sectors, including efforts to reduce agricultural and urban water use. Incentives and structured water rates are being explored to encourage homeowners and businesses to adopt water-saving practices.
Policy and legislation play a significant role in these conservation efforts. Recent laws, such as HB 453 and SB18, aim to protect the lake’s water by ensuring that conserved water reaches the lake and remains there. These legislative changes also seek to establish a more comprehensive regulatory framework for water usage, including for mineral extraction industries, to reduce their water consumption. The state is working on a Great Salt Lake Basin Integrated Plan to understand the complex water supply and demand dynamics.
Technological solutions and improved water management strategies are also being explored, such as better measurement and accounting models for water flow, a process sometimes called “water shepherding.” This ensures that water saved upstream is directed to the lake rather than being used elsewhere. Public awareness and education campaigns are also being utilized to foster community involvement and understanding of the lake’s plight and the importance of conservation.