For more than 150 years, humans have been taking more water out of the Salt Lake watershed than is flowing into it. They are now diverting about 40 percent of the river water (which would normally fill the lake) and using it for farming, industry, and human consumption. In October 2016, the Great Salt Lake reached its lowest recorded level: 1277.5 meters (4,191.2 feet), averaged between the lake’s north and south arms.

Five years of drought in the American West have contributed to the recent drop in the water line, as have higher-than-normal temperatures. But the region has seen dry cycles before, and according to scientists, there has not been a significant long-term change in precipitation in the basin. Nonetheless, the volume of water in Great Salt Lake has shrunk by 48 percent and the lake level has fallen 3.4 meters (11 feet) since 1847.