Salton Sea
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The Salton Sea is an inland saline lake, located in the Colorado Desert in Southern California, north of the Imperial Valley. The lake covers a surface area of approximately 376 square miles (974 km²), making it the largest lake in California. It varies in dimensions and area due to changes in agricultural runoff and rain. It averages 15 by 35 miles (24 by 56 km). Its maximum depth is 51 feet and its total volume is about 7.5 million acre-feet (9.3 km³). Sea inflow averages 1.36 million acre-feet per year (53 m³/s).
The Salton Sea falls within the territories of both Riverside County and Imperial County. Like Death Valley, it is located below sea level, with the current surface of the Sea at about 220 ft (65 m) below sea level. The deepest point in the Sea is only 5 feet higher than the lowest point in Death Valley. The Sea is fed by the New, Whitewater, and Alamo rivers, as well as a number of minor agricultural drainage paths and creeks.
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[edit] History
The creation of the Salton Sea of today started in 1905, when heavy rainfall and snowmelt caused the Colorado River to swell and breach an Imperial Valley dike. It took nearly two years to control the Colorado River’s flow into the formerly dry Salton Sink and stop the flooding. Once part of the vast inland sea which covered the area, the endorheic Salton Sink was the site of a major salt mining operation. As the basin filled, the town of Salton, a Southern Pacific Railroad siding and Torres-Martinez Indian land were submerged. The result of the sudden influx of water and the lack of any drainage from the basin resulted in the formation of the Salton Sea.
Though the current Salton Sea is a man-made (and accidental) creation of the 20th century, the Salton Sink has held significant bodies of water some times in the past. For example, scientists believe that 300 years ago a short-lived body of water, called Lake Cahuilla, existed in the valley. The area was briefly flooded in 1891. But all those bodies of water eventually disappeared through evaporation. The Salton Sea, on the other hand, is constantly replenished by more than one million acre-feet (1.2 km³) of runoff water from surrounding irrigated farming communities, sustaining its water level.
In the 1920s, the Salton Sea developed into a tourist attraction, because of its water recreation, and the waterfowl attracted to the area. The Salton Sea remains a major resource for migrating and wading birds. It has also had some success as a fishery in the past, with species such as mullet, corvina, sargo, and tilapia being introduced to the Sea from the 1930s to the 1950s. It has had some success as a resort area, with Salton City, Salton Sea Beach, and Desert Shores being built on the western shore and Desert Beach, North Shore, and Bombay Beach built on the eastern shore in the 1950s. The town of Niland is located 2 miles (3 km) southeast of the Sea as well. The evidence of geothermal activity is also visible. There are mud pots and mud volcanoes on the eastern side of the Salton Sea.
The lack of an outlet means that the Salton Sea is increasingly becoming an unstable system: variations in agricultural runoff cause fluctuations in water level (and flooding of surrounding communities in the 1950s and 1960s), and the relatively high salinity of the agricultural runoff feeding the Sea has resulting in an ever increasing level of salinity. By the 1960s, it was becoming apparent that the salinity of the Salton Sea was continuing to rise, jeopardizing some of the species living in it. The Salton Sea currently has a salinity exceeding 40‰ (parts per thousand), making it saltier than ocean water, and many species of fish are no longer able to survive in the Salton. It is believed that once the salinity surpasses 44‰, only the tilapia will be able to survive. Fertilizer runoff combined with the increasing salinity and inflow of highly polluted water from the northward-flowing New River have resulted in large algal blooms and elevated bacteria levels. The New River is considered to be the single most polluted river in America.
The high level of bacteria resulting from fish die-offs are a major threat to the avian population. In 1992 and 1996 large scale die-offs of grebes and pelicans occurred, demonstrating the unstable nature of the ecosystem.
High levels of selenium have also been found in the Sea and are thought to contribute to mortality and birth defect problems in the local bird populations. In 1997, investigators researching the death of fish discovered a parasite dinoflagellate known as Amyloodinium ocellatum in 22 of 23 dead fish. Algal blooms also lead to massive die-offs of the fish population due to oxygen starvation. There are often thousands of dead fish, mostly tilapia, lining the shore.
Many efforts, both governmental and grassroots, have arisen to find a solution for the pollution and salinity problems of the Sea. Without further human intervention, both the Salton Sea and the animal populations using it are threatened. Plans for large desalination plants, evaporation ponds, outlet pipelines to the ocean, and causeways dividing the lake into portions have been investigated as possible solutions.
Much of the current interest in the sea was spearheaded in the 1990s by Congressman Sonny Bono. His widow, Mary, was elected to fill his seat and has continued the fight, as has Representative Jerry Lewis (not the entertainer of the same name) of Redlands.
The increasing salinity, algae, and bacteria levels have taken their toll on tourism, and many of the Salton Sea resorts are now closed and abandoned. Before recent water control measures were implemented, the Salton Sea's surface tended to rise and fall severely, causing flooding problems in some of the surrounding communities. The area still draws over 150,000 vacationers a year, primarily to the local campsites, trailer parks, and the Salton Sea State Recreation Area.
The future of the Salton Sea is unclear, as intervention is required to manage the increasingly unstable system. Such intervention would require massive policy and financial commitments from the state and federal governments. The growth of San Diego, and its willingness to pay high prices for water, entices water districts to sell their water rather than dedicate it to agricultural purposes. As the Salton Sea is nearly completely dependent on agricultural water runoff, the lake is highly dependent on the path of water politics in the coming years.
[edit] Bird use at the Salton Sea
The Salton Sea has been termed a "crown jewel of avian biodiversity" (Dr. Milt Friend, Salton Sea Science Office). Over 400 species have been documented at the Salton Sea. Amazingly, the Salton Sea supports 30% of the remaining population of the endangered American White Pelican. [1] The Salton Sea is a major resting stop on the Pacific Flyway. The sea's rising salinity threatens to eliminate the habitat value for fish-eating birds, such as pelicans. Without restoration actions, the sea will also eventually fail to support the microorganisms necessary to support the many shorebirds that depend on the Salton Sea. Recently, a Ross's Gull, an Arctic bird, was sighted and photographed here.
[edit] Saving the Salton Sea
[edit] Past efforts and Proposals for a Sea Level Canal
Alternatives for "saving the Salton Sea" have been evaluated since the 1950s. Early concepts included costly "pipe in/pipe out" options, which would import lower salinity seawater from the Gulf of California or Pacific Ocean and export higher salinity Salton Sea water; evaporation ponds that would serve as a salt sink, and large dam structures that would partition the sea into a marine lake portion and a brine salt sink portion. Others advocate building a sea level canal to the Salton Sea from the Gulf of California. Given that the Sea is over 200 feet below sea level, a sea level canal would allow thousands of tons of lower salinity sea water to flow into the Sea without costly pumping or pipelines. Such a canal could be built large enough for recreational use and by ocean going vessels. A sea level canal would promote dual purposes as an inland port for Southern California and also serve as a recreational/environmental asset along its course for humans and wildlife in Mexico and the U.S. A sea level canal would also likely provide a way to regulate the shoreline of the Sea in a predictable manner.
In the late 1990s, the Salton Sea Authority, a local joint powers agency, and the U.S. Bureau of Reclamation, spearheaded efforts to evaluate and develop an alternative to save the Salton Sea. A Draft Environmental Impact Report/Environmental Impact Statement, which did not specify a preferred alternative, was released for public review in 2000.
Since that time, the Salton Sea Authority has developed a preferred concept [2] that involves the construction of a large dam that would impound water to create a marine sea in the northern and southern parts of the sea and along the western edge. The plan has been subject to some criticism for failing to properly address ecosystem needs, and for engineering practicality concerns such as local faulting, potentially devastating to such a plan.
Criticisms of the preferred plan issued by the Salton Sea Authority included:
- Construction failure when identified 200 feet of sediments fail to hold up the rock structures placed on top of them.
- Geological catastrophe when a major earthquake hits the nearby San Andreas Fault (feet away from the east end of the dike).
- Physical catastrophic failure as water is depleted from the south pond and water pressure pushes across the north pond against the soft sedimentary underlayment.
- Possible catastrophic failure by water blowing under the dike as water from the higher north pond etches its way under the dike.
- Massive alkali storms blowing across the area destroying crops from the south basin [3] exposing dried salt sediments resulting in crop damage and increased respiratory problems.
Many other concepts have been proposed [4], including piping water from the Sea to a wetland in Mexico, Laguna Salada, as a means of salt export, and one by Aqua Genesis Ltd to bring in sea water from the Gulf of California, desalinate it at the Sea using available geothermal heat, and selling the water to pay for the plan. [3] This concept [5] would involve the construction of over 20 miles (30 km) of pipes and tunneling, however, with the increasing demand for water at the coastline would provide an additional 1,000,000 acre feet (1.2 km³) of water to Southern California coastal cities each year, according to SDSU Professor Ronald A. Newcomb, SDSU College of Sciences, Center for Advanced Water Technologies.
[edit] Current state restoration process
The California State Legislature, by legislation enacted in 2003 and 2004 (SB 277 [6], SB 317 [7], SB 654 [8]and SB 1214 [9]), directed the Secretary of the California Resources Agency to prepare a restoration plan for the Salton Sea ecosystem, and an accompanying Environmental Impact Report. As part of this effort, which is based on State legislation enacted in 2003 and 2004. The Secretary for Resources has established an Advisory Committee to provide recommendations to assist in the preparation of the Ecosystem Restoration Plan, including consultation throughout all stages of the alternative selection process. The California Department of Water Resources and California Department of Fish and Game are leading the effort to develop a preferred alternative for the restoration of the Salton Sea ecosystem and the protection of wildlife dependent on that ecosystem. The Secretary of Resources is required to submit a report to the legislature, including a preferred alternative, by December 31, 2006.
[edit] Criticisms
Opponents of Salton Sea restoration say that with water so sparse in the area of the southwest, preserving a fluid inland lake is a waste of a critical resource. They believe that migrating wildlife would return to their original flyways and migration patterns.
Some believe that the most natural event for inland seas that exist in terminal basins is for the lakes to desiccate and become salt flats or dry lakebeds. Others have wondered how the area can be of such environmental concern when it was a manmade creation to begin with.
Proponents of preservation point to the potential economic damage to local agriculture, as the air pollution from the fine salts might destroy local crops and impact human health. Also of concern is the entire Coachella Valley area, which includes Palm Springs. It could be subjected to windstorm damage, as well as salts and odors blown in by such storms.
Proponents of preservation also point out that significant loss of habitat throughout the Pacific Flyway places increased importance on current remaining habitats, including the Salton Sea. For many species "original flyways" no longer exist. Many bird species that rely substantially on the Salton likely utilized ephemeral and permanent habitat throughout the Colorado River Delta and California's Central Valley, but this habitat is no longer supported, due to management of water resources within the U.S. (and, to a lesser degree, Mexico). Those who question how the area can be "of such an environmental concern" fail to consider the avian population implications and the extent of habitat loss throughout the Pacific Flyway - now covered mostly by urban development and freeways.
[edit] Media attention
The 2006 documentary film Plagues and Pleasures on the Salton Sea (narrated by John Waters) documented the lives of the inhabitants of Bombay Beach, Niland, and Salton City, as well as the ecological issues associated with the Sea.
[edit] Additional photos
Dead Tilapia |
Near Obsidian Butte |
Where the New River enters the Salton Sea |
Abandoned Buildings |
Sign on the west shore |
More ruins on the east shore |
Sunset in Salton Sea |
White Pelicans on the North Coast |
[edit] External links
- Salton Sea Authority
- Salton Basin chronology
- Salton Basin overview
- Salton Sea overview
- Hydrologic information
- US House Committee on Resources, which includes reports on the Salton Sea.
- Salton Sea data and other resources
- A Joint Powers Authority focused on restoring the Salton Sea
- US Bureau of Reclamation's Salton Sea Restoration Project Office
- National Geographic photos of the Salton Sea
- Geothermal energy generation in Imperial Valley
- Documentary - "Plagues & Pleasures on the Salton Sea" - narrated by John Waters
- http://www.fdungan.com/salton.htm One man's idea to save Salton Sea]
- Calexico New River Committee, New River Tributary
- Maps and aerial photos
- WikiSatellite view at - WikiMapia
- Satellite image from Google Maps, Windows Live Local
- Street map from Google Maps, or Yahoo! Maps, or Windows Live Local
- Topographic map from TopoZone
- Aerial image or topographic map from TerraServer-USA
cs:Saltonské moře de:Saltonsee fr:Salton Sea (lac) he:ימת סולטן fi:Salton Sea
Categories: Articles lacking sources from September 2006 | All articles lacking sources | Depressions | Endorheic lakes | Engineering failures | Geography of the Colorado Desert | Imperial County, California | Lakes of California | Riverside County, California | Shrunken lakes | Disasters in the United States
