The Earliest Printed Map of the Salton Sea
Fine early map of the Salton Sea area, published shortly after flooding from the Colorado River and poorly designed irrigation canals caused the flooding of what had previously been the town of Salton and vicinity, creating one of the largest inland lakes west of the Mississippi River over the course of several years in the first decade of the 20th Century.
The map was first issued in 1906, shortly after the Salton Sea was created, and updated in 1907 and 1908, by which time the Salton Sea had further grown and changed shape. The 1908 edition was re-issued several times over the following decades.
While the 1908 map is relatively common, the original 1906 map is quite scarce.
History of the Salton Sea
The area was once part of a vast inland sea that covered a large area of Southern California. Geologists estimate that for three million years, at least through all the years of the Pleistocene glacial age, a large delta was deposited by the Colorado River in the southern region of the Imperial Valley. Eventually, the delta reached the western shore of the Gulf of California, creating a barrier that separated the area of the Salton Sea from the northern reaches of the Gulf. Were it not for this barrier, the entire Salton Sink along with the Imperial Valley would be submerged as the Gulf would extend as far north as Indio.
Evidence that the basin was occupied periodically by multiple lakes includes wave-cut shorelines at various elevations preserved on the hillsides of the east and west margins of the present lake, the Salton Sea.
Throughout the Spanish period of California's history, the area was referred to as the "Colorado Desert" after the Colorado River. In a railroad survey completed in 1855, it was called "the Valley of the Ancient Lake". On several old maps from the Library of Congress, it has been found labeled "Cahuilla Valley" (after the local Native American tribe) and "Cabazon Valley" (after a local Native American chief – Chief Cabazon). "Salt Creek" first appeared on a map in 1867 and "Salton Station" is on a railroad map from 1900, although this place had been there as a rail stop since the late 1870s. Until the advent of the modern sea, the Salton Sink was the site of a major salt-mining operation.
In 1900, the California Development Company began construction of irrigation canals to divert water from the Colorado River into the Salton Sink, a dry lake bed. After construction of these irrigation canals, the Salton Sink became fertile for a time, allowing farmers to plant crops.
Within two years, the Imperial Canal became filled with silt from the Colorado River. Engineers tried to alleviate the blockages to no avail. In 1905, heavy rainfall and snowmelt caused the Colorado River to swell, overrunning a set of headgates for the Alamo Canal. The resulting flood poured down the canal, breached an Imperial Valley dike, and ran down two former dry arroyos: the New River in the west, and the Alamo River in the east. Over about two years, these two newly created rivers sporadically carried the entire volume of the Colorado River into the Salton Sink.
The Southern Pacific Railroad tried to stop the flooding by dumping earth into the canal's headgates area, but the effort was not fast enough, and the river eroded deeper and deeper into the dry desert sand of the Imperial Valley. A large waterfall formed as a result and began cutting rapidly upstream along the path of the Alamo Canal that now was occupied by the Colorado. This waterfall was initially 15 feet high, but grew to 80 feet high before the flow through the breach was stopped. Originally, it was feared that the waterfall would recede upstream to the true main path of the Colorado, becoming up to 100 to 300 high, at which point it would be practically impossible to fix the problem.
As the basin filled, the town of Salton, a Southern Pacific Railroad siding, and Torres-Martinez Native American land were submerged. The sudden influx of water and the lack of any drainage from the basin resulted in the formation of the Salton Sea.
OCLC locates the following examples: US Geological Survey (Denver and National Center), UCLA, University of Chicago, University of Washington and University of Wisconsin (American Geographical Society collection).