The Great Salt Lake is in crisis

Northern Utah’s Great Salt Lake—the largest saltwater lake in the western hemisphere—is rapidly disappearing and by some estimates may be totally gone within just a few years despite frantic efforts to save it. 

Since 1850, the lake has lost 73 percent of its water and 60 percent of its surface area, and as more people move to the region, the water that typically feeds the lake is increasingly being diverted for agricultural, municipal, and industrial needs. What’s more, over the past few decades, a series of challenges—including climate change and the worst megadrought in at least 1,200 years—has impacted the cyclical climatic conditions that have sustained the lake for millennia. 

Now, with 2026 shaping up to be Utah’s worst snowpack year on record, the federal government is eyeing ways to shore up the Great Salt Lake. Utah officials also recognize the growing threat, and in recent years, the state legislature has passed laws to help increase the lake’s water levels while earmarking more funding for water conservation programs. Some officials have also proposed large-scale projects to bring water back to this increasingly desiccated landscape.

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This legislative urgency is warranted because the disappearance of Great Salt Lake would be a multifaceted disaster. Nearly 80 percent of Utah’s population lives within the Great Salt Lake’s watershed, and the lake contributes roughly $1.3 billion to Utah’s GDP each year through the mining and aquaculture industries as well as recreational activity. Its shrinking footprint has increased the frequency of toxic dust storms, leading some experts to regard the lake’s possible demise as an “environmental nuclear bomb.” And lower water levels boost the lake’s salinity through evaporation, which threatens this already fragile ecosystem by drying out critical habitat. 

“Great Salt Lake [is] a very present symbol of how we need to change the way we understand, predict, manage, and use water resources in the West,” says Paul Brooks, a hydrologist at the University of Utah. Humans, Brooks says, must adopt “a broader and longer-term perspective.”

How did the Great Salt Lake get so salty?

There is no Great Salt Lake without the 200,000-square-mile basin it calls home. The Great Basin, which covers most of Nevada and parts of Utah, Wyoming, California, and Oregon, formed tens of millions of years ago as part of the northern section of North America’s Basin and Range Province, a series of mountain ranges and valleys that took shape as the North American tectonic plate began to stretch apart.

“Because of the stretching of the crust, [the plate] broke up into individual blocks—mountain range-sized blocks,” says Jack Oviatt, a former geologist at Kansas State University. As the plate continued to expand, these blocks lifted up, and basins formed in between. “There’s the possibility that if there is enough precipitation, lakes will form in those basins,” Oviatt says. 

The Great Salt Lake emerged from one such lake, a much larger body of water known as Bonneville Lake. This massive, ancient freshwater reservoir, which formed around 30,000 years ago, covered roughly 20,000 square miles of the Great Basin at its height, rivaling the size of Lake Michigan today. 

Around 16,000 years ago, as global temperatures rose toward the tail end of the Ice Age, Lake Bonneville began to shrink. Because the Great Basin watershed is terminal (or endorheic), meaning no water can flow out of the basin into external rivers or oceans, Lake Bonneville, like many other salt lakes found throughout the West and around the world, slowly dried up, which increased its salinity as water evaporated.

Over the span of a few thousand years, the modern-day shoreline of the Great Salt Lake emerged, and around the same time, humans arrived in the region. “Great Salt Lake has never existed without people—as the margins formed, people were appearing,” says Bonnie Baxter, a biologist at Westminster University and director of the Great Salt Lake Institute. The first inhabitants likely saw a different landscape with sprawling wetlands, gushing springs and even megafauna such as giant ground sloths, mammoths, and saber-toothed cats. 

For thousands of years, Indigenous Shoshone, Ute, Goshute, and Paiute communities have gathered along the lakeshore and served as its stewards, harvesting salt and other resources. When pioneers from the Church of Jesus Christ of Latter-Day Saints—a religious movement commonly referred to as Mormonism—settled in Utah in the mid-19th century, they began diverting water from the Jordan, Bear, and Weber rivers that flow from the Wasatch and Uinta mountain ranges to the Great Salt Lake. “This was their Dead Sea,” Baxter says, referring to the Middle East’s famously salty inland sea that’s frequently mentioned in the Bible. “Making it their homeland meant diverting water.”  

This practice continued to expand as Salt Lake City’s population increased over the following century, but diverting water wasn’t the only anthropogenic change. In 1959, the construction of a rock-filled railroad causeway effectively carved the lake in two, creating a northern and southern arm. Because the structure cut off the north arm from all three rivers that infuse the lake with life-sustaining freshwater, salinity levels there rose even higher. Now, the north arm is roughly 10 times saltier than the ocean, with a salinity level of around 34 percent. (For comparison, the south arm has a salinity level of around 12 percent.) Some types of algae and bacteria thrive in this hypersaline environment and give the north arm’s water a pinkish hue—a visual distinction that can even be seen from space. Because of remarkably high salinity, only unicellular archaea and bacteria are known to survive in the north arm’s waters.

Today, the lake’s elevation hovers at about 4,191 feet above sea level—around 20 feet lower than its highest level, recorded in 1983, during which the West experienced a remarkably strong El Niño climactic event. It has been steadily shrinking since the beginning of the region’s megadrought in 2000.  A difference of 20 feet might not seem like a lot, but the Great Salt Lake is extremely wide and shallow compared to many other terminal lakes, which only increases its rate of evaporation. Annually, the lake loses around 2 million acre-feet of water. 

With the watershed's growing population requiring more water, a long-lasting megadrought drying out the region, and climate change raising temperatures around the world, the Great Salt Lake is not likely to survive—at least not without some serious help.

Troubled Waters

The Great Salt Lake is no stranger to change. Because the region is influenced by fluctuating periods of wet and dry conditions, driven by both the El Niño–Southern Oscillation and the Pacific Quasi-Decadal Oscillation—ocean systems that influence weather across the West—water levels have naturally risen and fallen for millennia. But in the era of climate change, that climatic machine is slowly malfunctioning. “Over the last 25 or 30 years, the dry periods are a little bit drier and longer and the wet periods are a little bit shorter,” Brooks says. “That is probably the biggest sign of climate change.” 

It’s a one-two punch. Drier sediments means the Great Salt Lake needs more water to fill to a healthy elevation while snowpack similarly first seeps into the ground up in the mountains, which greatly reduces runoff to the lake's three main tributaries. 

But scientists aren’t just worried about filling the lake, they’re also concerned about what may be lurking in the exposed lakebed. Increasingly frequent dust storms have kicked up sediment containing heavy metals such as lead, copper, and arsenic, a mix of natural and anthropogenic toxins fed largely by decades of industrial and agricultural runoff. That dust, a report from Brigham Young University claims, could contribute to a concerning increase in respiratory illness along with potential “developmental defects, cognitive impairment, cardiovascular damage, and cancer” while also damaging crops and causing premature snowmelt in nearby mountains.

Of course, desiccation also impacts the animals that call the area home. The Great Salt Lake has become a critical habitat for hundreds of migratory bird species such as the threatened Wilson’s Phalarope and Eared Grebe, both of which could face extinction if the ecosystem were to collapse. It’s “probably the most important body of water in the Pacific Flyway,” a migratory path that stretches from Alaska to Patagonia, Baxter says. But this important avian pitstop—a vital habitat for brine flies, an insect that many bird species rely on for food—is drying out. 

The lake’s increasing salinity is also disrupting another resident: the south arm’s population of native brine shrimp. The Great Salt Lake produces 40 to 50 percent of the world’s brine shrimp, a critical component of the global aquaculture industry. Their eggs are a major food source for much of the world’s farmed fish and shrimp. While brine shrimp typically thrive in saline waters, too much salt (salinity levels of 160 grams/ liter, or more than 16 percent salinity) can stress them out and prevent them from growing and reproducing properly.

To avoid this environmental catastrophe, a patchwork of agencies and organizations across the state are working to help Utah residents manage their water use, which relies heavily on the rivers that feed the lake. Utah Water Savers offers rebates for low-flow appliances and encourages residents to swap out water-hungry lawns for drought tolerant plants, such as yarrow, Utah agave, and Rocky Mountain Juniper. The Utah Department of Agriculture and Food’s water optimization program is helping farmers transition from thirsty crops like alfalfa to sorghum or millet. And a new $815-million water reclamation facility will return millions of gallons of treated wastewater a day to Farmington Bay, an arm of Great Salt Lake, when it opens in the summer of 2026.

And with the possibility of $1 billion in federal aid flowing to Utah to salvage the lake, state officials have begun proposing a slew of ambitious plans to restore the Great Salt Lake—including developing a network of pipelines that could funnel water from wetter regions of the U.S., such as the Great Lakes or the Mississippi River Valley, and constructing desalination plants in California to similarly pipe water to the lake. 

But both Brooks and Baxter say these projects wouldn’t be completed in time to save the lake, which recent estimates suggest may dry out completely by the end of the decade if the region’s stroke of bad climate luck continues unabated. “We’ve really reached a tipping point,” Brooks says. “There’s no silver bullet. Everyone is going to have to contribute, and we’re going to have to think about water differently.”