The Great Salt Lake - Facts and Information

What is the Great Salt Lake?:

Great Salt Lake, located in the northern part of the U.S. state of Utah, is the largest salt lake in the western hemisphere, the fourth-largest terminal lake in the world, and the 37th-largest lake on Earth.

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 the balance of evaporated water is mineral-free, concentrating the lake 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.

Great Salt Lake differs in elevation between the south and north parts. The Union Pacific Railroad causeway divides the lake into two parts. The water-surface elevation of the south part of the lake is usually 0.5 to 2 feet (0.6 m) higher than that of the north part because most of the inflow to the lake occurs from the south. (The split actually causes the north and south halves to be different colors)

Just how big is it?

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)(8,547 km²).

The Ecology of the GSL:

Brine shrimp

Brine shrimp are not only the most visible inhabitants of Great Salt Lake and are very important to the ecology of the lake, serving as a major source of food for migratory birds. They are also valuable for the hard-walled eggs they produce, which are commercially harvested and used worldwide in the aquaculture industry.

Birds

Birds: Great Salt Lake supports between 2 and 5 million shorebirds, as many as 1.7 million eared grebes, and hundreds of thousands of waterfowl during spring and fall migration. Because of its importance to migratory birds, the lake was designated a part of the Western Hemisphere Shorebird Reserve Network in 1992. The lake and its marshes provide a resting and staging area for the birds, as well as an abundance of brine shrimp and brine flies that serve as food.

Planktonic and benthic habitats

The planktonic and benthic habitatin Great Salt Lake consists of the open water inhabited by brine shrimp, phytoplankton (algae), bacteria, and other small zooplankton. These organisms are all free-swimming or float in the water. The benthic habitat consists of the bottom substrate of the lake and its associated organisms. These organisms are primarily brine-fly larvae and benthic algae.

Boating:

Since the very salty water of the lake is corrosive to metal, motorized craft (other than the shrimp harvesting fleet) are not common on Great Salt Lake. Water skiing and jet skis are very rare on this lake, but an occasional sea kayak appears near Saltair Marina. (Can you imagine the impact of a skier falling at 30 mph in water that is much denser than fresh water?). While there are few speedboats, sailboats are popular on the lake and the Saltair Marina is where they hang out. Boat slips (boating map of Great Salt Lake) are available for seasonal rental and the Great Salt Lake Yacht Club is an active organizer of skill and racing events. Note that winds on the lake are erratic. You may be able to go where you planned but return may be difficult. The lake is very shallow and there is considerable hazard of running aground in areas near the shoreline or any of the islands.

The Salt Industry:

The salts of the lake are primarily sodium chloride (common salt), although small amounts of other elements and salts are also present, including magnesium, potassium, sulfate, and carbonate. There are about 4.5 to 4.9 billion tons of salt in the lake, and about 2.2 million tons of salt enter the lake annually from surface-and ground-water flow. The salt industries extract about 2.5 million tons of sodium chloride and other salts and elements from the lake annually.

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.

Facts:

The largest U.S. lake west of the Mississippi River

The 4th largest terminal lake (no outlet) in the world

A remnant of Lake Bonneville, a prehistoric freshwater lake that was 10 times larger than GSL

About 75 miles long, and 28 miles wide, and covers 1,700 square miles

Has a maximum depth of about 35 feet

Typically 3 to 5 times saltier than the ocean

Fish free, the largest aquatic critters are brine shrimp and brine flies

One of the largest migratory bird magnets in Western North America