Coachella Valley is a large valley landform in Southern California. The valley extends for approximately 45 miles (72 km) in Riverside County southeast from the San Bernardino Mountains to the saltwater Salton Sea, the largest lake in California. It is approximately 15 miles (24 km) wide along most of its length, bounded on the west by the San Jacinto Mountains and the Santa Rosa Mountains and on the north and east by the Little San Bernardino Mountains. The San Andreas Fault crosses the valley from the Chocolate Mountains in the southeast corner and along the centerline of the Little San Bernardinos. The fault is easily visible along its northern length as a strip of greenery against an otherwise bare mountain.
The Chocolate Mountains are home to a United States Navy live gunnery range and are mostly off-limits to the public. In comparison to the “Inland Empire” (Riverside-San Bernardino area and the California desert), some people refer to the IE ’s sub-region Coachella Valley as the “Desert Empire” to differentiate it from the neighboring Imperial Valley. Geographers and geologists sometimes call the area, along with the Imperial Valley to the south, the “Cahuilla Basin” or the “Salton Trough”.
Geographically, it is the agricultural and recreational desert valley in Southern California, United States (U.S.), east of Riverside and San Bernardino. Populated by nearly 600,000 people, the valley is part of the 14th largest metropolitan area in the United States, the Inland Empire. The Coachella Valley is the second largest sub-region in the Inland Empire metropolitan area, after the Greater San Bernardino Area.
Visible landmarks are the Salton Sea (230ft below sea level) at rear left, along towards the center the Santa Rosa Mountains behind Indio and the San Jacinto Mountains behind Palm Springs. In the valley floor, the San Andreas Fault is clearly visible. At the rear right is the 11,500 ft (3,500 m) San Gorgonio MountainThe area is surrounded on the southwest by the Santa Rosa and San Jacinto mountain ranges, and the Little San Bernardino Mountains on the northeast. These mountains peak at around 11,000 feet (3,400 m) and tend to average between three to five thousand feet. This effectively blocks the marine layer familiar to most other Southern Californian areas. Sometimes a weather system can come through one of the narrow passes, or up from the Gulf of California as Hurricane Kathleen did in September 1976. Daily high temperatures in the summer rarely go lower than 105 °F. During winter, the daytime temperatures range from 70 °F (21 °C) to 80 °F (27 °C), making it a popular winter resort destination.
Although geographically the valley is the northwestern extension of the Colorado Desert to the southeast, the irrigation of over 100,000 acres (405 km²) of the valley since the early 20th century has allowed widespread agriculture. In its 2006 annual report, the Coachella Valley Water District listed the year’s total crop value at over $576 million or almost $12,000 per acre.2 The Coachella Canal, a concrete-lined aqueduct built between 1938 and 1948 as a branch of the All-American Canal, brings water from the Colorado River to the valley. The Colorado River Aqueduct, which provides drinking water to Los Angeles and San Diego, crosses the northeast end of the valley along the base of the Little San Bernardino Mountains (the Joshua Tree National Park).
The San Andreas Fault runs down the Valley’s east side. Because of this fault, the Valley has many hot springs. The Santa Rosa Mountains to the West are part of the Lake Elsinore Fault zone. The results of a prehistoric sturzstrom can be seen in Martinez Canyon. The Painted Canyons of Mecca feature smaller faults as well as Precambrian, Tertiary and Quaternary rock formations, unconformities, badlands and desert landforms. Seismic activity is what triggers earthquakes, a natural, but on occasion, destructive phenomena in the Coachella Valley. Fault lines cause hot water springs or geysers to rise from the ground. These natural water sources are what made inhabitation and development possible in the otherwise inhospitable desert environment of the Coachella Valley. There have been major earthquakes that have affected the Coachella Valley. For instance, the Landers Earthquake in 1992 caused some damage in the valley. An earthquake of local origin which caused considerable damage was the 1986 North Palm Springs earthquake, which registered at a magnitude of 6.0, injuring 29 people and destroying 51 homes. 12
This desert environment hosts a variety of flora and fauna, including the endangered California Fan Palm, Washingtonia filifera.3, the Bighorn sheep a species of rams live in the Santa Rosa and San Jacinto mountain ranges, and the fringe-toed lizard, an indigenous desert reptile whose numbers are increasingly under the U.S. Endangered Species Act. Desert wildlife in the Coachella Valley includes localized subspecies of ants, bats, beetles, blackbirds, bobcats, cougars, coyotes, diamondbacks, fleas, foxes, gnats, gophers, hawks, horseflies, jackrabbits, kangaroo rats, mosquitoes, mountain lions, owls, pigeons, quails, rattlesnakes, ravens, roaches, roadrunners, scorpions, spiders, termites, ticks, vipers, wasps, whip scorpions or “vinegaroons”, and wildcats.