Research: Human Use Shrinking the Great Salt Lake

October 26, 2017

These two images reveal the shrinking Great Salt Lake shoreline between 1989 and 2015. (Courtesy of Johnnie Moore)

MISSOULA – A University of Montana geosciences professor emeritus recently contributed to research that reveals human water consumption, rather than long-term climate change, has greatly reduced the size of Utah’s Great Salt Lake.

Johnnie Moore said the work of his multiagency team shows the Great Salt Lake is shrinking as a result of human water use upstream. The team’s analysis indicates that water consumption has lowered the lake by about 11 feet, representing a reduction of lake volume of 48 percent.

"Continued removal of moisture from the Great Salt Lake will cause huge direct ecological effects, as well as economic and social losses, for 2 million people in the nearby Salt Lake metropolitan area,” Moore said. “These are problems occurring worldwide as nearly all saline lakes are desiccated by human actions.”

The work was published online by Nature Geoscience at https://www.nature.com/articles/ngeo3052.

“Although not often thought of as important, Earth’s large saline lakes provide a wide range of benefits to humans and wildlife,” he said. “But these unique environments are under threat as saline lakes worldwide shrink at alarming rates, reducing wildlife habitat and economic benefits while threatening human health.”

Moore said the Great Salt Lake produces $1.32 billion per year from mineral extraction, brine shrimp cyst production, and recreation. Its abundant food and wetlands attract millions of shorebirds and several million migrating waterfowl, making it a mecca for bird watching and hunting.

He said there is a tendency for many water managers and users to invoke climate change as the culprit for the decline of saline lakes. Although climate change has an impact, water development in arid basins represents a larger and more immediate challenge.

“Saving these unique and important resources will come only from reductions in consumptive water use by improved efficiency,” Moore said. “We also need a much deeper understanding of how saline lake systems respond to climate change and direct human actions.”

Moore’s partners in the research came from Utah State University, the Utah Division of Water Resources, the Rocky Mountain Research Station in Ogden and Salt Lake Community College.

Contact: Johnnie Moore, emeritus professor, UM Department of Geosciences, 406-243-2341, johnnie.moore@umontana.edu.