The American West’s Salt Lakes Are Turning to Dust

This story originally appeared on High Country News and is part of the Climate Desk collaboration.

Last summer, scientists at the National Oceanic and Atmospheric Administration observed dust blowing 85 miles from its source, Lake Abert and Summer Lake, two dried-up saline lakes in southern Oregon. This has happened before: Saline lakebeds are some of the West’s most significant sources of dust. California’s Owens Lake is the nation’s largest source of PM10, the tiny pollutants found in dust and smoke, while plumes blowing off the 800 square miles of the Great Salt Lake’s exposed bed have caused toxin-filled dust storms in Salt Lake City.

Saline lakes are rapidly losing water to climate change and agricultural and urban uses, becoming some of the West’s most threatened ecosystems. Now, new legislation is offering some support. On December 27, President Joe Biden signed the bipartisan Saline Lake Ecosystems in the Great Basin States Program Act, which allocates $25 million in funding for research and monitoring at saline lakes across the Great Basin. While this funding is an important step, it cannot give the lakes what they really need: more water.

The Interior West is full of salt lakes, created when snowmelt pools in the valley bottoms of the Basin and Range region. The valleys have no outflow, so the water remains until it evaporates, leaving behind the particles that were suspended in it. These accumulate over time, giving the lakes a high salinity.

“It creates a unique system that supports brine shrimp and alkali flies that can feed incredible populations of migratory birds,” said Ryan Houston, executive director of the Oregon Natural Desert Association, which seeks to conserve Oregon’s high desert, including Summer Lake and Lake Abert.

Yet this balance of runoff, salts, and evaporation also makes saline lakes highly sensitive to climate change. Decreasing snowpack and increasing evaporation due to higher temperatures means that there is less water in the lakes and a higher concentration of salt. That stresses shrimp and flies, which have adapted over time to specific salinities, and it also exposes dry lakebeds, creating dangerous dust storms.

Decades of diversions for agricultural and municipal use have also taken the lakes’ water. California’s Owens Lake, for instance, has been almost completely dry for nearly a century since its water was diverted to Los Angeles. A report released this month by Utah scientists and conservation organizations warned that the combination of water diversions and climate change has put the Great Salt Lake on track to disappear within five years. 

Many see poor air quality as the main reason to save the lakes. But the dust is a sign that the entire ecosystem is withering. Saline lakes are key stops on the Pacific Flyway, the bird migration route that extends from Alaska to Patagonia, Chile. “That we’re worried about dust says to me that we’ve already gone past the point of Lake Abert being lost as part of the Pacific Flyway, its most important ecological value,” said Houston. Over 80 species of birds either inhabit or migrate through Lake Abert, and 338 species depend on the Great Salt Lake.