A worrying study published last month in Environmental Challenges claims that nearly two-thirds of the Great Salt Lake’s shrinkage is attributable to human use of river water that otherwise would have replenished the lake.
Utah’s Great Salt Lake is a relic of a once-vast lake that occupied the same site during the Ice Age. The lake’s level has fluctuated since measurements of it began in 1847, but it’s about 75 miles (120 kilometers) long by 35 miles (56 km) wide with a maximum depth of 33 feet (10 meters). The Great Salt Lake’s water levels hit a record low in 2021, which was usurped the following year.
According to the recent paper, about 62% of the river water that otherwise would have refilled the lake has instead been used for “anthropogenic consumption.” The research team found that agricultural use cases were responsible for 71% of those human-driven depletions; furthermore, about 80% of the agricultural water is used for crops to feed just under one million cattle.
“The research highlights the alarming role of water consumption for feeding livestock in driving the lake’s rapid depletion,” said William Ripple, an ecologist at Oregon State University and co-author of the paper, in a university release.
The lake is no stranger to change; One Utah State University report indicated that the lake’s water levels have been in decline since the mid-19th century. As the United States Geological Survey’s Utah Water Science Center reports, the lake’s bisection by a railroad causeway in 1959 significantly changed the salinity levels in the newly created halves of the lake, and because the water body has no outlet rivers or inflow, its water levels change dramatically due to evaporation or substantial rain.
“Abnormally large snowmelt inflow during the 1980s and 1990s served to temporarily obscure the long-term decline in lake levels, and the lake actually reached its highest level in more than a century in 1987,” Ripple said. “But it has been dropping by roughly 4 inches per year on average since then.”
The researchers proposed a goal of reducing anthropogenic river water consumption in the area by 35% to begin refilling the lake, as well as a detailed breakdown of specific reductions within livestock feed production.
“We find that the most potent solutions would involve a 61% reduction in alfalfa production along with fallowing of 26–55% of grass hay production,” the team wrote, “resulting in reductions of agricultural revenues of US$97 million per year, or 0.04% of the state’s GDP.” The team added that Utah residents could be compensated for their loss of revenue. It’s an easier plan to propose on paper than sell folks on as a reality, but it is a pathway towards recovery for the Great Salt Lake.
As the team added, the lake directly supports 9,000 jobs and $2.5 billion in economic productivity, primarily from mining, recreation, and fishing of brine shrimp. Exposed saline lakebeds (as the Great Salt Lake’s increasingly are with its decreasing water levels) are also associated with dust that can pose health risks due to its effects on the human respiratory system.
For now, the Great Salt Lake’s average levels and volume continue to decrease. But the team’s research has revealed a specific pain point and suggested ways to reduce the strain on the great—but diminishing—water body.
This post was originally published on here
