Great Salt Lake

Great Salt Lake, located in the northern part of the U.S. state of Utah, is the largest salt water lake in the western hemisphere, the fourth-largest terminal lake in the world, and the 37th-largest lake on Earth. In an average year the lake covers an area of around 1,700 square miles (4,400 km2), but the lake's size fluctuates substantially due to its shallowness. For instance, in 1963 it reached its lowest recorded level at 950 square miles (2,460 km²), but in 1987 the surface area was at the historic high of 3,300 square miles (8,500 km2).

The lake is the largest remnant of Lake Bonneville, a pluvial lake which covered much of western Utah in prehistoric times. The Great Salt Lake is endorheic (has no outlet besides evaporation) and has very high salinity, far saltier than sea water. The Jordan, Weber, and Bear rivers (the three major tributaries) deposit around 1.1 million tons of minerals in the lake each year, and since water (but not the minerals) is constantly being evaporated, the concentration of minerals increases further. Because of its unusually high salt concentration, most people can easily float in the lake as a result of the higher density of the water, particularly in the saltier north arm of the lake, Gunnison Bay. The lake's shallow, warm waters cause frequent, sometimes heavy lake-effect snows during late fall, early winter, and spring.

Although it has been called "America's Dead Sea", the lake provides habitat for millions of native birds, brine shrimp, shorebirds, and waterfowl, including the largest staging population of Wilson's Phalarope in the world.

Island

Categorically stating the number of islands is difficult, as the method used to determine what is an island is not necessarily the same in each source. Since the water level of the lake can vary greatly between years, what may be considered an island in a high water year may be considered a peninsula in another, or an island in a low water year may be covered during another year. According to the US Dept of the Interior/US Geological Survey, "there are eight named islands in the lake that have never been totally submerged during historic time. All have been connected to the mainland by exposed shoals during periods of low water." In addition to these eight islands, the lake also contains a number of small islands, rocks, or shoals which become fully or partially submerged at high water levels.

The Utah Geological Survey, on the other hand, states "the lake contains 11 recognized islands, although this number varies depending on the level of the lake. Seven islands are in the southern portion of the lake and four in the northwestern portion."

The size and whether they are counted as islands during any particular year depends mostly on the level of the lake. From largest to smallest, they are Antelope, Stansbury, Fremont, Carrington, Dolphin, Cub, Badger, Strongs Knob, Gunnison, Goose, Browns, Hat (Bird), Egg Island, Black Rock and White Rock. Dolphin, Gunnison, Cub, and Strongs Knob are in the northwest arm. The rest are in the southern portion. There are also a number of small, unnamed islands.

Commerce

With its sudden storms and expansive spread, the lake is a great test of sailing skills. Single mast, simple sloops are the most popular boats. Sudden storms and lack of experience on the part of boatmen are the two most dangerous elements in boating and sailing on the Great Salt Lake.

The lake's north arm contains deposits of oil, but it is of poor quality and it is not economically feasible to extract and purify it. As of 1993, around 3,000 barrels (480 m3) of crude oil had been produced from shallow wells along the shore.

Solar evaporation ponds at the edges of the lake produce salts and brine (water with high salt quantity). Minerals extracted from the lake include: sodium chloride (common salt), used in water softeners, salt lick blocks for livestock, and to melt ice on local roadways; potassium sulfate (potash), used as a commercial fertilizer; and magnesium-chloride brine, used in the production of magnesium metal, chlorine gas, and as a dust suppressant. Food-grade salt is not produced from the lake, as it would require further costly processing to ensure its purity. Mineral-extraction companies operating on the lake pay royalties on their products to the State of Utah, which owns the lake.

The harvest of brine shrimp cysts during fall and early winter has developed into a significant local industry, with cysts selling for as high as $35 a pound. Brine shrimp were first harvested during the 1950s and sold as commercial fish food. In the 1970s the focus changed to their eggs, known as cysts, which were sold primarily outside of the United States to be used as food for shrimp, prawns, and some fish. Today, these are mostly sold in the Orient and South America. The amount of cysts and the quality are affected by several factors, but salinity is most important. The cysts will hatch at 2 to 3% salinity, but the greatest productivity is at salinities above about 10%. If the salinity drops near 5 to 6%, the cysts will lose buoyancy and sink, making them more difficult to harvest.

A large resort called Saltair has been operated on the southern shore of the lake off and on for many years. Rising and lowering water levels have affected Saltair, and it has burned down twice. Currently it serves as a concert venue. The new resort, built in 1981 after large fires completely destroyed the second and largest in the 1960s, is only a shadow of the resort's former grandeur.

Dramatically fluctuating lake levels have inhibited the creation and success of tourist-related developments. There is a problem with pollution of the lake by industrial and urban effluent. Also, especially when the waters are low, decay of insects and other wildlife give the shore of the lake a distinctive odor which may keep some tourists from coming near the lake. Despite these issues, the lake remains one of Utah's largest tourist attractions. Antelope Island State Park is a popular tourist destination that offers panoramic views of the lake, hiking and biking trails, wildlife viewing and access to beaches.

Miscellaneous

The Great Salt Lake as seen looking north towards Antelope Island from Sunset Beach

Spiral Jetty

The northwest arm of the lake, near Rozel Point, is the location for Robert Smithson's work of land art, Spiral Jetty (1970), which is only visible when the level of Great Salt Lake drops below 4,197.8 feet (1,280.2 m) above sea level.

Oolitic sand

The lake and its shores contain oolitic sand, which are small, rounded, or spherical grains of sand made up of a nucleus (generally a small mineral grain) and concentric layers of calcium carbonate (lime) and look similar to very small pearls.

Lake monster

In mid-1877, J.H. McNeil was with many other Barnes and Co. Salt Works employees on the lake’s north shore in the evening. They claimed to have seen a large monster with a body like a crocodile and a horse’s head in the lake. They claimed this monster attacked the men, who quickly ran away and hid until morning. This creature is regarded by some to have simply been a buffalo in the lake. Thirty years prior, "Brother Bainbridge" claimed to have sighted a creature that looked like a dolphin in the lake near Antelope Island. This monster is called by some the North Shore Monster.

History

While the lake was well known by local Native Americans, it entered the annals of written history through the records of Silvestre Vélez de Escalante, who learned of its existence from the Timpanogos Utes in 1776. No name was given to it at the time, and it was not shown on the map by Bernardo Miera y Pacheco, the cartographer for the expedition. It was first seen by Europeans in 1824, apparently independently, by Jim Bridger and Etienne Provost. Shortly thereafter other trappers saw it and walked around it.

Most of the trappers, however, were illiterate and did not record their discoveries. As oral reports of their findings made their way to those who did make records, some errors were made. Escalante had been on the shores of Utah Lake, which he named Laguna Timpanogos. It was the larger of the two lakes that appeared on Miera's map. Other cartographers followed his lead and charted Lake Timpanogos as the largest (or larger) lake in the region. As people came to know of Great Salt Lake, they interpreted the maps to think that "Timpanogos" referred to Great Salt Lake. On some maps the two names were used synonymously. In time "Timpanogos" was dropped from the maps and its original association with Utah Lake was forgotten.