Salton Sea: The Accidental Lake

Salton Sea is a shallow, saline and endorheic rift lake located in California’s San Andreas Fault in the Imperial and Coachella Valleys. The lake accidentally formed on a salt sink, after the diversion controls of the Colorado River broke and flooded the area for almost 2 years.

Salton Sea Stats

Lake NameSalton Sea
CountryUnited States
Surface area956.860
Maximum depth15.0
Average depth8.9
Lake typeRift lake
Catchment area20050.80
Altitude-71.0
Volume8.560
InflowsAlamo River, New River, Whitewater River
OutflowsNone
Shore length201.88
SettlementsBombay Beach, Desert Beach, Desert Shores, Salton City, Salton Sea Beach, North Shore
Residence time3888.2
Trophic stateEutrophic
Average discharge25.481

Geologic History and Formation

The Salton Sink is a complex of ancient drainages, hills and faults, an extension of the Gulf of California which is entirely surrounded by land. It was once part of an inland sea, which used to cover a large area of Southern California. Geologists affirm that for approximately 3 million years and through all of the Pleistocene epoch, there was a large delta here, which was deposited by the Colorado River in the Southern Region of the Imperial Valley. This delta ultimately reached the western bank of the Gulf of California, creating a barrier which separated the Salton Sea from the northern reaches of the Gulf. If this barrier hadn’t been created, the entire Salton Sea, together with the Imperial Valley and the Anza-Borreg Desert State Park would all be submerged now, and the Gulf would extend all the way to the city of Indio in the North.

Since the lake has been separated from the ocean with the help of this natural barrier, the Salton Basin has been, in turn, a freshwater lake, an increasingly saline lake, and a dry desert basin. Its aspect changed according to the inflowing rivers and the balance between this inflow and the evaporation the basin witnessed. The lake only existed during times when it would fill up with rain water and river flow, a cycle which has been repeating itself for thousands of years.

Wave-cut shorelines at various elevations which can be seen on the eastern and western hillsides which border the lake testify for the fact that the basin was periodically occupied by multiple lakes at a time. This reveals that the basin has been occupied intermittently merely a couple of hundred years ago. The descendants of the Native people confirmed that the latest cycle occurred sometimes between 1600 and 1700.

The last lake of the Pleistocene Epoch which occupied the basin was called Lake Cahuilla (after the local Native American Tribe), also referred to as Lake LeConte or the Black Sea on old maps. During the Spanish period of California’s history, the area was cited as the “Colorado Desert” and in a railroad survey published in 1885 it was called “The Valley of the Ancient Lake”. On the old maps courtesy of the Library of Congress the area is called “Cahuilla Valley” and Cabazon Valley (named after a local Native American Chief, Cabazon). The name “Salt Creek” is first observed on a map dating from 1867, whilst “Saltous Station” can be found on a railroad map from 1900.

The Accidental Creation

Salton Sea currently occupies the lowest elevation of the Salton Sink in Southern California. It is mainly fed by the New, Whitewater and Alamo rivers, along with agricultural runoffs as well as smaller streams and creeks. In 1900 the California Development Company started constructing a large set of irrigation canals with the goal of diverting water from the Colorado River into the dry lakebed of Salton Sink. After the irrigation canal was successfully constructed, the dry land became fertile and local farmers planted crops there. But unfortunately within 2 years’ time the Imperial land was filled with silt from the Colorado River. Engineers rushed to alleviate the blockages without any success.

A heavy rainfall and snowmelt in 2005 caused the extreme swelling of the Colorado River, which quickly overran a set of headgates for the Alamo Canal. The flood came pouring down the canal, breaching an important dike, running down two creeks which were formerly dry. When the heavy rainfall occurred, a project was under works, aiming to increase the flow of water to surrounding farmlands, irrigation canals were dug from the Colorado River into the heart of the valley. Instead of risking the buildup of silt, engineers decided to cut into the bank of the Colorado River to further increase waterflow. This resulted in an overwhelmed outflow which went past the finished canal system and poured into the Salton Basin for nearly 2 years, filling up the dried lakebed, thus creating a modern sea.

The Southern Pacific Railroad tried to stop the massive flooding by dumping earth into the headgates of the canals, but this method proved to be too slow as the river rolled deeper and deeper into the dry desert land. When the water first reached the Imperial Valley, it formed a waterfall and began cutting rapidly upstream along the path of the Alamo Canal. This waterfall was said to be 4.6 meters tall, and managed to grow to up to 24 meters before the flow through the beach was halted. At that time it was feared the waterfall would recede upstream to the Colorado River, which would’ve made it too tall to be fixed. Numerous towns were submerged as the water filled up the basin, including the Southern Pacific Railroad siding of Salton and the Native-American Torres-Martinez.

The lake’s exact size often varies, depending on water fluctuations, agricultural runoff and rainfall. The salinity of the lake 44 g/l, much more than the Pacific Ocean’s salinity (35 g/l). This concentration grows at a rate of 1% each year, which means that 4 million short tons of salt are deposited in the valley yearly.

Earthquake Zone

The lake and the surrounding basin are located on the San Andreas Fault, the San Jacinto Fault, and the Imperial Fault Zone. Geologists have confirmed the fact that numerous earlier floodings of the Colorado River were linked to earthquakes occurring along the San Andreas Fault. With the help of sonar maps specialists have also determined that when the basin was filled by Lake Cahuilla, strong earthquakes higher than a magnitude of 7 ruled over the region every 180 years.

Computer remodeling tests have shown that the normal faults located in the area are susceptible to deviatoric stress loading by the filling of water. A risk of 7-8 magnitude earthquakes happening continuously exists in the region. The rise of the sea level in the past is partially to blame for the increased salinity of the lake and potential changes in the sea level might also occur in the future. Hydrothermal vents and diffusion of salts are also contributing factors to the salinity level of Salton Sea.

Local People

The Cahuilla Natives have occupied the area for thousands of years together with other California Indians. When they arrived, the Salton Sea was a much larger body of water and they referred to it as Lake Cahuilla. The ancient lake’s existence is confirmed by the early house pits, middens and other artifacts that have been discovered by archaeologists.

Local legends say that the lake once covered the whole valley, and as it began to shrink, people started moving closer and closer to the lake, moving their villages and houses down from the mountains. They survived mostly by building fish traps of stones in the shallower areas of the lake.

They probably met the first Europeans in 1540, when the early Spanish explorer Melchior Diaz prospected the region for Hernan Cortez, the Spanish Conquistador. In 1774 Juan Bautista de Auza crossed the area looking for the trade route.

The locals’ first encounter with the Anglo-Americans was in 1840, when they allowed travellers to pass through their lands. This kindness took an unexpected turn when the land of the locals was taken by the new settlers by 1850, leaving them without the necessary resources to survive. Although once more than 10,000 Cahuilla natives populated the area, there are less than 3,000 descendants living there today.

Flora and Fauna

The lake and its surroundings boast a diverse collection of wildlife. Although it once had a booming fish population, because of the increased salinity of the waters, the main fish present in the lake are Tilapia. Other species of fish can be found in the rivers and canals feeding the lake, such as threadfin shads, carps, red shiners, channel catfish, white catfish, largemouth basses and mosquitofish.

These fish feed the majority of the wintering birds, including white pelicans, kingfishers, egrets and herons. The lake serves as a meeting point of birds, giving a temporary home to more than 400 species, boasting the most diverse and significant population of bird life in the Continental USA. The pray species, such as the peregrine falcons, osprey and ferruginous hawks usually arrive in Fall. The fields located in the proximity of Salton Sea support flocks of snow geese, ducks, sandhill cranes and the biggest population of burrowing owls in the state. Gambel’s quail, greater roadrunner and the endangered Yuma clapper rails are some of the resident birds.

The dominant vegetation in the lake’s precinct is made up of drought-tolerant desert scrubs, creosote bush, desert salt bush, fan palms and tamarirks. Cottonwoods and willows grow alongside streams and springs.

Dangers and Issues

The Salton Sea area was once a highly successful resort complex, with Salton City, Desert Shores, Salton Sea Beach on the west, Desert Beach on the east and Bombay Beach bordering the lake from the north. The resort towns were mostly built in the 1950’s and after their initial success many shrunk in size and were later abandoned, mostly because of the lake’s increase in salinity levels and the pollution which originated from agricultural runoff. Many of the fish died off due to the heavy pollution, washing up on the shores of the lake in large quantities. The stench of fish and the smell of the eutrophic lake boasting booming algae caused a definite decline in tourism. Many people visit the lake area for the sole purpose of exploring the abandoned structures left in the ghost resort towns.

Evidence of geothermal activity has been observed in the Salton Sea area, and mudpots and mud volcanoes can also be found on the eastern shores of the lake. On the southeastern shore one can find numerous geothermal electricity generation plants. The 11 commercial power stations within the Salton Sea geothermal field produce 186.62 megawatts of electricity.

The variations of agricultural runoff often cause fluctuations in the lake’s water levels, which occasionally flooded the surrounding areas in the 1950’s and 1960’s. As the lake became an increasingly saline body of water by the ‘60s, it put the lives of numerous species in jeopardy. The fertilizer runoff also caused a high level of eutrophication in the lake, which in change caused large algal blooms and high bacteria levels. By 2014 large strips of the lakebed were exposed and because of mandated water transfers to the metropolitan areas, the salt levels in the lake increased even more. But the shrinking of the lake doesn’t only kill fish, it also interrupts bird migration, causes dust clouds to form and has a negative impact on local tourism as well.

Remediation Proposals and Plans

Proposals for saving the lake have been suggested since 1955. The current involvement in remediation efforts for Salton Sea has been sparked by Congressman Sonny Bono in 1990. After his death his wife took over the activity and founded the Sonny Bono Salton Sea Restoration Project in 1998. In the late ‘90s the Salton Sea Authority along with the US Bureau of Reclamation began their efforts to estimate and prepare a solution to save the problematic lake. A draft of the Environmental Impact Report was released to the public in 2000, but it didn’t actually offer any concrete solutions. The Salton Sea Authority then developed a preferred concept, suggesting the construction of a dam which would impound water in order to create a marine sea at the northern and southern parts of the lake. Other suggestions include piping water from the sea to a Mexican wetland, Laguna Salada, as a form of salt export. Another concept suggested brining in seawater from the Gulf of California, desalinating at the sea through geothermal heat and sell the water.

In 2003 the Imperial Irrigation District settled to sell a part of its allotment from the Colorado River to the San Diego County Water Authority for 45 years. The California State Legislature led the Secretary of California Resources Agency to put together a restoration plan for the Salton Sea Ecosystem. The California Department of Water Resources and the California Department of Fish and Game aim to develop a preferred alternative to the restoration of the lake’s ecosystem. In January 2008 the California Legislative Analyst’s Office released a report entitled “Restoring the Salton Sea” with its main objectives being the reduction of the water amount, the erection of a barrier and perimeter dikes. Plans also included the reconstruction of the lake’s southern part to a saline habitation complex and reduce the agricultural runoff in order to replenish the sea.

Movies and Pop Culture References

The documentary film entitled “Plagues and Pleasures of the Salton Sea” covers the first 100 years of the Salton Sea’s existence, and its environmental issues. The short film “The Accidental Sea” presents the history of the lake, whilst a whole episode of the History Channel’s “Modern Marvels” is dedicated to describing the natural and man-made events that led to the formation of the lake.

The motion picture of 2002 entitled “The Salton Sea” stars Val Kimmer, while one of the most famous Michael Jackson videos “In the Closet” was actually filmed at the lake. An episode of the “Life after People” series focuses on how resort towns would decay at Salton Sea, whilst another of “Journey to Planet Earth” showcases that the plight of the sea might lead to another Aral Sea-like disaster.

Fragments of the 1954 crime drama called “Highway Dragnet” were filmed at the lake, and Salton Sea also served as the setting for the 1957 United Artists science-fiction movie entitled “The Monster that Challenged the World”. The alternative American rock band, Linkin Park, posed for their third album cover at Salton Sea and the lake also served as an inspiration for the Alamo Sea in the popular Grand Theft Auto V video game. The lake was present in Curtis Harrington’s 1948 short film called “On the Edge” and was also featured in an independent drama from 2011 entitled “Little Birds”.

Tourism and Leisure

The Salton Sea area is visited by more than 150,000 tourists each year. The region boasts 5 campgrounds, numerous boat launches, campsites, designated picnic areas and even RV hookups. The most popular activities are fishing, bird-watching, kayaking, waterskiing, swimming, picnicking, and hiking on the numerous nature trails the area has to offer. The best time to visit the Salton Sea is between October and May. Although from June to September the weather can be very hot, it is actually the best time for fishing. Tilapia can be caught both from the shore and from boats. A part of the lake is a designated national wildlife refuge area.

Salton Sea Map