SciTech

Receding salt lakes cause great economic damage

Utah’s Great Salt Lake, about 75-mile long and 35-mile wide is the largest saltwater lake in North America. Human activity has been causing its levels to deplete drastically which causes other ecological and economic disturbances. (credit: Courtesy of Brigitte Werner via Wikimedia Commons) Utah’s Great Salt Lake, about 75-mile long and 35-mile wide is the largest saltwater lake in North America. Human activity has been causing its levels to deplete drastically which causes other ecological and economic disturbances. (credit: Courtesy of Brigitte Werner via Wikimedia Commons)

Utah’s Great Salt Lake, an iconic 1700-square-mile natural feature that gives the state’s capital its name, is disappearing.

The lake contains about half of the water it did in 1847, and the water level is still dropping. In 2016, it hit its lowest point ever recorded.

Researchers have confirmed that the lake’s present-day water level is not a natural variation of water levels over time: it is a direct consequence of human overuse of the lake’s resources. The lake’s desiccation is a result of a century and a half of diverting water away from the lake for agricultural use.

Large salt bodies of water all over the world are suffering from the same problem. The Aral Sea in Central Asia and Lake Urmia in Iran are some of the more-well known ones, but major salt lakes in places like Argentina, Australia, and Kenya are all drying up as well.

The desiccation of salt lakes has a huge environmental impact. Salt lakes are a crucial part of their local ecosystems. If the water level goes down, the remaining water gets saltier, and the increased salinity can kill off fish species if it gets too high. Salt lakes are also home to brine shrimp, small organisms that serve as important food for migratory birds who use salt lakes as a rest stop on their journey, or even as a nesting site. A decline in the brine shrimp population can cause bird populations to suffer.

When salt lakes disappear because of human activity, it’s not just wildlife that suffers: we’re also harming ourselves. Receding salt lakes leave behind swaths of incredibly dusty soil, which gets picked up by wind and dispersed into the air.

The dust contributes to air pollution and increases local rates of asthma and other respiratory ailments that can be caused or agitated by pollution. Mitigating dust pollution around California’s Owens Lake, another retreating salt lake, is expected to cost the city of Los Angeles $3.6 billion.
Receding salt lakes can also do great economic damage. The industries that directly mine the lake’s resources will suffer: companies that harvest salt from the lake or collect brine shrimp eggs (a surprisingly profitable industry) can’t stay in business if there’s no lake to harvest from. The tourism and recreation economy will also suffer: Activities like swimming and boating lose profit, and fishing and birdwatching become unrewardingly difficult or impossible.
If the lake recedes so far that it no longer touches adjacent towns, it may become difficult just to access it.

The researchers who confirmed the Great Salt Lake’s desiccation hope that by recognizing that the problem is caused by humans and not natural variation in water levels, we will be able to accept our responsibility for sustainable water management and begin seriously working on solutions to the problem.