what is the history if the great salt lake?

Answer 1

Great Salt Lake

Satellite Photo of the Great Salt Lake as it looked in the summer of 2003
The Great Salt Lake as seen looking north towards Antelope Island from Sunset Beach
Great Salt Lake from airspace over Salt Lake CityGreat Salt Lake is an endorheic saline lake in northern Utah, much saltier than the ocean. It is the remnant of the prehistoric pluvial Lake Bonneville in the Great Basin. It covers an area of around 1,700 square miles, but this is subject to substantial fluctuations. The lake has very high salinity because it has no outlet to the sea. Three feeder rivers deposit around 1.1 million tons of minerals in it each year; the balance of evaporated water is mineral-free, concentrating the lake further.


Geography
Salt Lake City and its suburbs are located to the southeast and east of the lake, between the lake and the Wasatch Mountains, but land around the north and west shores are almost uninhabited. The Great Salt Lake Salt Flats lie to the west, and the Oquirrh Mountains rise to the south.

The Great Salt Lake is fed by three major rivers and several minor streams. The Bear River starts in the Uinta Mountains and flows in to the northeast arm of the lake. The Weber River also starts in the Uinta Mountains and flows into east edge of the lake. The Jordan River starts at freshwater Utah Lake and flows into the southeast corner of the lake. A railroad line—the Lucin Cutoff—runs across the lake, crossing the southern end of Promontory Peninsula. The mostly-solid causeway supporting the railway divides the lake into three portions: northeast arm, northwest arm and southern. This causeway prevents the normal mixing of the waters of the lake due to it's lack of water passages, and since there are no rivers, with the exception of a few minor streams, flowing directly into the northwest arm (also called "Gunnison Bay"), it is now noticeably saltier than the rest of the lake.

Water levels have been recorded since 1843, averaging about 1,280 m (~4,200 ft) above sea level. Since the Great Salt Lake is a shallow lake with gently sloping shores around all edges except on the south side, small variations in the water level can greatly affect the extent of the shoreline. During low levels, the lake is difficult to approach because it is fringed by long and sometimes quite odorous mud flats.

Because the water level is variable, it can rise dramatically in wet years and fall during drought years. The water level is also affected by the amount of water flow diverted for agricultural and urban uses. The Jordan and Weber rivers are particularly diverted for other uses. In the 1880s Grove Karl Gilbert predicted that the lake — then in the middle of many years of recession — would virtually disappear except for a small remnant between the islands. Record high levels in the 1980s caused massive property damage for owners on the eastern side, and started to erode the base of Interstate 80. In response, the state built pumps on the western side of the lake to pump dangerously high water out into the west desert, but as of 2004 these pumps are dry and miles away from the lake's shore. They are, however, maintained in the event the lake rises to those levels again.


Islands
There are ten named islands in the Great Salt Lake. From largest to smallest, they are Antelope, Stansbury, Fremont, Carrington, Dolphin, Cub, Badger, Strongs Knob, Gunnison, Hat (Bird) and Egg Island. Dolphin, Gunnison, Cub, and Strongs Knob are in the northwest arm, and the rest are in the southern portion. There are also a number of small, unnamed islands whose size and number greatly depends on the level of the lake.

Antelope and Fremont Islands are extensions of the Oquirrh mountain range. Stansbury Island and other smaller islands are extensions of the Stansbury mountain range. The lake is deepest in the area between these island chains, about 10.7 m (~35 ft) deep at the 1,280 m (~4,200 ft) level. The lake averages 4 m (~13 ft) deep at the same level. When the water levels are low (as they were in late 2004 averaging under 1279 m (~4195 ft)), Antelope island becomes connected to the shore as a peninsula, as do some of the other islands. In fact, "Stansbury Island" and Strongs Knob remain peninsulas unless the water level rises above average. At high levels, some of the smaller islands become completely submerged. (See also "Commonly Asked Questions About Utah's Great Salt Lake and Ancient Lake Bonneville" at Utah Geological Survey.)


Great Salt Lake ecosystem
The high salinity of the lake makes it uninhabitable for all but a few species. However, the fresh- and salt-water wetlands along the eastern and northern edges of the Great Salt Lake provide critical habitat for millions of migratory shorebirds and waterfowl in western North America. These marshes account for approximately 75 percent of the wetlands in Utah. Some of the birds that depend on these marshes include: Wilson's phalarope, red-necked phalarope, American avocet, black-necked stilt, marbled godwit, snowy plover, western sandpiper, long-billed dowitcher, tundra swan, American white pelican, white-faced ibis, California gull, eared grebe, peregrine falcon, bald eagle, plus large populations of various ducks and geese.


American avocets at Bear River Migratory Bird RefugeGreat Salt Lake wetland/wildlife management areas include the Bear River Migratory Bird Refuge; Gillmor Sanctuary; Great Salt Lake Shorelands Preserve; Salt Creek, Public Shooting Grounds, Harold Crane, Locomotive Springs, Ogden Bay, Timpie Springs and Farmington Bay Waterfowl Management Areas.

Several small island in the lake provide critical nesting areas for various birds. Access to Hat, Gunnison and Cub islands is strictly limited by the State of Utah in an effort to protect nesting colonies of American white pelican (Pelecanus erythrorhynchos).

The only aquatic animals able to live in the lake are tiny brine shrimp (Artemia franciscana). Their tiny, hard-walled eggs or cysts (diameter of about 200 micrometers) are harvested in quantity during the fall and early winter. They hatch easily, and are fed to prawns in Asia. They are also are sold as novelty "Sea-Monkeys." There are also two species of salt flies and some bacteria and algae.

Salinity differences between the sections of the lake separated by the railroad causeway result in significantly different biota. A phytoplankton community dominated by blue-green or green algae tint the water south of the causeway a greenish color. North of the causeway, the lake is dominated by halophilic bacteria which gives the water an unusual reddish or purplish color. These color differences are especially noticeable in satellite photographs. Although brine shrimp can be found in the arm of the lake north of the causeway, studies conducted by the Utah Division of Wildlife Resources seem to indicate that these animals are likely transient. Populations of brine shrimp are mostly restricted to the lake's south arm.



Pink Floyd the flamingo
As of 2005, a solitary Chilean flamingo named Pink Floyd winters at the Great Salt Lake. It escaped from Salt Lake City's Tracy Aviary in 1987 and now lives in the wild, eating brine shrimp and socializing with gulls and swans. Utah residents have suggested petitioning the state to release more flamingos in an effort to keep Floyd company and as a possible tourist attraction. Wildlife biologists have resisted these efforts, saying that deliberate introduction of a non-native species would be ecologically unsound and might have detrimental consequences. See Christian Science Monitor article


Commerce
Shallow artificial ponds at the edge of the lake are used to produce salt magnesium and other minerals for commercial sale.

The harvest of brine shrimp cysts during fall and early winter has developed into a significant local industry.

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.

A resort called Saltair has been operated on the southern shore of the lake. Rising and lowering water levels have affected Saltair, and it has burned twice.

Dramatically fluctuating lake levels has inhibited the creation and success of tourist-related developments. Despite this, 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, wildife viewing and access to beaches.

The northwest arm of the lake, near Rozel Point, is the location for Robert Smithson's significant work of land art, Spiral Jetty (1970).