The Great Salt Lake is the largest saltwater lake in the Western Hemisphere, and the eighth-largest terminal lake in the world. It lies in the northern part of the U.S. state of Utah, and has a substantial impact upon the local climate, particularly through lake-effect snow. It is a remnant of Lake Bonneville, a prehistoric body of water that covered much of western Utah.
In an average year the lake measures approximately 1,700 square miles, but its area can fluctuate substantially due to its low average depth of 16 feet. In the 1980s, it reached a historic high of 3,300 square miles and the West Desert Pumping Project was established to mitigate flooding by pumping water from the lake into the nearby desert. In 2021, after years of sustained drought and increased water diversion upstream of the lake, it fell to its lowest recorded area at 950 square miles, falling below the previous low set in 1963.
Its three major tributaries, the Jordan, Weber, and Bear rivers together deposit around 1.1 million tons of minerals in the lake per year. Having no outlet besides evaporation, these minerals accumulate and give the lake very high salinity and density.