The Salton Sea, 35 miles long and between nine and 15 miles wide, is the largest lake by surface area in California. Its history is complex—and an anomaly in the natural world.
Today’s Salton Sea lies 228 feet below sea level, on the site of the much-larger ancient Lake Cahuilla. Peaking at 40 feet above sea level, Lake Cahuilla encompassed much of the Imperial, Mexicali and Coachella valleys, most recently between 500 and 1,000 years ago.
With evaporation and no outlet, over the years, Lake Cahuilla dried up, leaving a huge 2,000-square-mile desert sink—from the Gulf of California to the Banning Pass. A horizontal dark band from the earlier shoreline is easily spotted along the cliffs near today’s Salton Sea. The ancient shoreline also left distinct terraces and tufa deposits around Travertine Point. The oral histories of the local bands of Native Americans include the existence of a large lake about 500 years ago.
In the 1850s, the dry Salton Sink attracted the attention of Oliver M. Wozencraft, a former Indian agent and member of the California Constitutional Convention. He theorized that instead of desert sand, the earth under the former lake was alluvial soil, which would welcome farming, given enough water. In 1859, the California Legislature granted Wozencraft all rights in the Salton Sink. He died in 1887 before attracting investors to help him get water to the area.
However, his efforts caught the attention of three men: George Chaffey, Charles R. Rockwood and Anthony H. Heber. In 1896, they formed the California Development Company, and by 1901, they were able to divert a portion of the Colorado River’s flow to begin irrigating the desert. The water flowed from near Yuma, into Mexico, and then north into the Imperial Valley.
Chaffey designed the canal diverting the water. In the 1880s, along with developing the California communities of Etiwanda and Ontario, he created the idea of mutual water companies and built the first hydroelectric plant in California. A world-renowned engineer, Chaffey had previously provided irrigation water in Australia to help colonize arid regions. Thanks to Chaffey, the irrigation of the Imperial Valley led to a boom, and by the end of 1904, more than 100,000 acres of land had been reclaimed.
Chaffey eventually severed his relationship with the others, and after he left, Rockwood especially grew impatient with the rate of water flow designed by Chaffey. He ordered a canal cut to bypass the gate controlling the water flow. The initial Colorado River water flow was low due to below-average winter storms. Also, Mexico was slow to put a gate on its side of the new bypass canal.
With heavier rainfall, disaster was inevitable.
Early in 1905, the first of five floods surged down the diversionary canal, and attempts to close it became futile. By the end of June, 14,000 cubic feet of water per second was settling into the below-sea-level Salton Sink. Ironically, one of the flooding victims was the California Development Company itself, which was later taken over by the Southern Pacific Railroad to prevent bankruptcy.
The water created not only the Salton Sea, but irrigated much of the Imperial Valley, attracting both farmers and wildlife. In 1930, the Salton Sea Wildlife Refuge was established for the protection of ducks, geese and shore birds. The sea became a key location on the Pacific Flyway, as more than 400 species stop there on their annual migration.
During the 1930s and 1940s, the All-American Canal and Coachella Canal were constructed to better harness the water. During World War II, commercial fishermen caught mullet in the Salton Sea to help supply coastal fish markets.
The 1950s and ’60s marked the heyday of the Salton Sea for tourism and recreation. The lake attracted fishermen, water-skiers and campers. The Salton Sea State Recreation Area opened in 1955; while not very heavily trafficked today, the park is still open and features an informative visitor center.
Communities came into being. Salton City was established as a residential town on the northwest shore. Also on the west side, Desert Shores and Salton Sea Beach were developed, while Bombay Beach was established on the eastern shore. In 1962, the North Shore Beach and Yacht Club Estates opened. In the early 1950s, corvina and gulf croaker were successfully established in the Salton Sea, creating a sports fishery that thrived for a couple of decades. Sargo (a silvery grunt) were also introduced and became the most abundant fish caught in Salton Sea until their numbers begin declining.
As the years went by, the Salton Sea got saltier and saltier. By the early 1960s, the California Department of Fish and Game predicted that the Salton Sea would eventually die by 1980 or 1990 because of salinity levels. Diking systems were discussed to reduce salinity levels, but in 1976, Hurricane Kathleen flooded the Imperial Valley farmland and increased the level of the Salton Sea. Above-average rainfall for the next few years flooded many of the shoreline resorts.
By the early 1980s, the Salton Sea’s salinity exceeded 40 parts per thousand, considerably greater than nearby oceans. Fishing was discouraged due to selenium and other pollutants.
Evaporation has been offset somewhat by nearby irrigation, keeping a large shallow lake there, although its salinity has remained very high. The Salton Sea is also full of toxic chemicals from fertilizers and sewage—making it one of Southern California’s biggest pollution concerns—and its rotten-egg-like hydrogen sulfide smell sometimes wafts into the Coachella Valley.
In 1993, the Salton Sea Authority was formed by Riverside County, Imperial County, the Coachella Valley Water District and the Imperial Irrigation District to address the myriad problems, including damage to wildlife. Throughout the years, conservation efforts on both the state and federal levels have tried to manage the Salton Sea water level and salinity to improve its habitat and recreation usage.
Today, the state-led Salton Sea Management Program is tackling the problems with a multi-faceted approach, which includes restoring parts of the sea, creating wetlands for habitat restoration, and planting vegetation to help suppress dust. The goal is to cover nearly 30,000 acres of exposed lakebed with projects by 2028.
Some recent news about the Salton Sea could be a game-changer. It was discovered that the Salton Sea contains one of the largest lithium brine deposits in the world—with an estimated 18 million metric tons of lithium, at a value of about $540 billion. According to Newsweek magazine, “California Gov. Gavin Newsom has described the region as the Saudi Arabia of lithium mining. … If harnessed successfully, it could cement California’s leadership in clean energy technology.”
With the introduction of lithium, the future of the Salton Sea promises to be as fascinating as its past.
Sources for this article include It Happened in Southern California by Noelle Sullivan (Falcon Publishing, 1996); Roadside History of California by Ruth Pittman (Mountain Press Publishing, 1995); The Desert Revolution by Lowell L. Blaisdell (University of Wisconsin Press, 1962); Imperial Valley by Tracey Henderson (Neyenesch Printers, 1968); “What Next for California’s Salton Sea After $540Bn ‘White Gold’ Discovery,” Newsweek, April 6, 2025.