California's Colorado Desert is a part of the larger Sonoran Desert. It encompasses approximately 7 million acres (28,000 km2), including the heavily irrigated Coachella and Imperial valleys. It is home to many unique flora and fauna.
The Colorado Desert is a subdivision of the larger Sonoran Desert encompassing approximately 7 million acres (28,000 km2). The desert encompasses Imperial County and includes parts of San Diego County, Riverside County, and a small part of San Bernardino County.
Most of the Colorado Desert lies at a relatively low elevation, below 1,000 feet (300 m), with the lowest point of the desert floor at 275 feet (84 m) below sea level, at the Salton Sea. Although the highest peaks of the Peninsular Ranges reach elevations of nearly 10,000 feet (3,000 m), most of the region's mountains do not exceed 3,000 feet (900 m).
In this region, the geology is dominated by the transition of the tectonic plate boundary from rift to fault. The southernmost strands of the San Andreas Fault connect to the northernmost extensions of the East Pacific Rise. Consequently, the region is subject to earthquakes, and the crust is being stretched, which will result in a sinking of the terrain over time.
The Colorado Desert's climate distinguishes it from other deserts. The region experiences greater summer daytime temperatures than higher-elevation deserts and almost never experiences frost. In addition, the Colorado Desert experiences two rainy seasons per year (in the winter and late summer), especially toward the southern portion of the region; the more northerly Mojave Desert usually has only winter rains.
The west coast Peninsular Ranges, or other west ranges, of Southern California–northern Baja California, block most eastern Pacific coastal air and rains, producing an arid climate. Other short or longer-term weather events can move in from the Gulf of California to the south, and are often active in the summer monsoons. These include remnants of Pacific hurricanes, storms from the southern tropical jetstream, and the northern intertropical convergence zone.
The region's terrestrial habitats include creosote bush scrub; mixed scrub, including yucca and cholla cactus; desert saltbush; sandy soil grasslands; and desert dunes. Higher elevations are dominated by pinyon pine and California juniper, with areas of manzanita and Coulter pine. In addition to hardy perennials, more than half of the desert's plant species are herbaceous annuals, and appropriately timed winter rains produce abundant early spring wildflowers. In the southern portion of the region, the additional moisture supplied by summer rainfall fosters the germination of summer annual plants and supports smoketree, ironwood, and palo verde trees.
Common desert wildlife include mule deer, bobcat, desert kangaroo rat, cactus mouse, black-tailed jackrabbit, Gambel's quail, and red-diamond rattlesnake. Among sensitive species are flat-tailed horned lizard, Coachella Valley fringe-toed lizard, desert tortoise, prairie falcon, Andrews' dune scarab beetle, peninsular bighorn sheep, and California leaf-nosed bat. The best place to spot wildlife is at the wetland refuges along the Colorado River, Cibola National Wildlife Refuge and Imperial National Wildlife Refuge.
In the Colorado Desert's arid environment, aquatic and wetland habitats are limited in extent but are critically important to wildlife. Runoff from seasonal rains and groundwater springs forms desert arroyos, desert fan palm oases, freshwater marshes, brine lakes, desert washes, ephemeral and perennial streams, and desert riparian vegetation communities dominated by cottonwood, willow, and non-native tamarisk. Two of the region's most significant aquatic systems are the Salton Sea and the Colorado River. While most desert wildlife depend on aquatic habitats as water sources, a number of species, such as the arroyo toad, desert pupfish, Yuma rail, and southwestern willow flycatcher, are restricted to these habitats. In some places, summer rains produce short-lived seasonal pools that host uncommon species like Couch's spadefoot toad.
Desert fan palm oases are rare ecological communities found only in the Colorado Desert. They occur only where permanent water sources are available, such as at springs or along fault lines, where groundwater is forced to the surface by the movement of hard impermeable rock, and can be found in the San Jacinto, Santa Rosa, and Little San Bernardino mountains, in the canyons of Anza-Borrego Desert State Park, and along the San Andreas Fault in the Coachella Valley. The only palm native to California, Washingtonia filifera (desert fan palm), grows at the oases.
Some sub-regions of the Colorado Desert contain endemic flora. Along the Lower Colorado River Valley, in-flow side canyons, flatlands, or low-to-higher level elevations, at least three such flora occur: Hesperocallis undulata (desert lily), Nolina bigelovii (Bigelow's nolina), and Peucephyllum schottii (desert fir).
The Colorado Desert is one of the least-populous regions in California, but human activities have had substantial impacts on the region's habitats and wildlife. Many unique communities, particularly aquatic and dune systems, are limited in distribution and separated by vast expanses of inhospitable, arid desert terrain. Even limited human disturbances can have markedly deleterious effects on the endemic and sensitive species supported by these unique regional systems.
Some of the greatest human-caused effects on the region have resulted from the water diversions and flood control measures along the Colorado River. These measures have dramatically altered the region's hydrology by redistributing the region's water supply to large expanses of irrigated agriculture and metropolitan coastal areas such as Los Angeles and San Diego. The once-dynamic Salton Sea and Colorado River ecosystems are now controlled by human water management. Because of the scarcity of water resources in the desert environment, these alterations have had substantial impacts on regional wildlife and habitats. In addition, portions of the region are experiencing substantial growth and development pressures, most notably the Coachella Valley.
Anza-Borrego Desert State Park (ABDSP) is a California state park located within the Colorado Desert of southern California, United States. The park takes its name from 18th century Spanish explorer Juan Bautista de Anza and borrego, the Spanish word for sheep. With 600,000 acres (240,000 ha) that includes one-fifth of San Diego County, it is the largest state park in California.
The park occupies eastern San Diego County and reaches into Imperial and Riverside counties, enveloping two communities: Borrego Springs, which is home to the park's headquarters, and Shelter Valley.Area codes 760 and 442
Area code 760 is a California telephone area code that was split from area code 619 on March 22, 1997. Area code 442 is an overlay of 760 that became effective on November 21, 2009. It encompasses much of the southeastern and southernmost portions of California. The area includes Imperial, Inyo, and Mono counties, as well as portions of San Diego, Riverside, San Bernardino, Los Angeles and Kern counties.Big Maria Mountains
The Big Maria Mountains are located in the southeastern part of the U.S. state of California, near the Colorado River and Arizona. The range lies between Blythe and Vidal, and west of U.S. Route 95 in California and east of Midland. The mountains are home to the Eagle Nest Mine and reach an elevation of 1,030 meters, (3,379 ft). A power line that runs from Parker Dam to Yuma, Arizona runs through the range. A smaller range, the Little Maria Mountains, lie to the west of the Big Marias.Cahuilla
The Cahuilla, also known as ʔívil̃uqaletem or Ivilyuqaletem, are a Native American people of the inland areas of southern California. Their original territory included an area of about 2,400 square miles (6,200 km2). The traditional Cahuilla territory was near the geographic center of Southern California. It was bounded to the north by the San Bernardino Mountains, to the south by Borrego Springs and the Chocolate Mountains, to the east by the Colorado Desert, and to the west by the San Jacinto Plain and the eastern slopes of the Palomar Mountains.Chiriaco Summit, California
Chiriaco Summit is a small unincorporated community and travel stop located along Interstate 10 in the Colorado Desert of Southern California. It lies 19 miles (31 km) west of Desert Center on the divide between the Chuckwalla Valley and the Salton Sea basin at an elevation of 1,706 feet (520 m).
The ZIP Code is 92201, and the community is inside area codes 442 and 760.
The town has a general aviation airport, Chiriaco Summit Airport. A California Department of Transportation rest stop on Interstate 10, west of Chiriaco Summit, is called "Cactus City", an ironic name referring to a non-existent city.Chuckwalla Mountains
The Chuckwalla Mountains are a mountain range in the transition zone between the Colorado Desert—Sonoran Desert and the Mojave Desert, climatically and vegetationally, in Riverside County of southern California.Desert Palms, California
Desert Palms is a census-designated place in the Coachella Valley of eastern Riverside County, southern California.Deserts of California
The Deserts of California have unique ecosystems and habitats, a sociocultural and historical "Old West" collection of legends, districts, and communities, and they also form a popular tourism region of dramatic natural features and recreational development. All of the deserts are located in eastern Southern California, in the Western United States.Dos Palmas Spring
Dos Palmas Spring is an artesian spring in Riverside County, California where it lies at the foot of the Orocopia Mountains. It is only one of several such springs in the area that create an oasis in the Colorado Desert there.Indio Hills Palms
Indio Hills Palms Park Property and the Coachella Valley Preserve, located in the Indio Hills, contain the 1,000 Palms Oasis and are a protected area in the Coachella Valley, located east of Palm Springs near Palm Desert, California. The Coachella Valley National Wildlife Refuge is contained within the Coachella Valley Preserve, and all are in the Colorado Desert section of the Sonoran Desert and adjacent to the Lower Colorado River Valley region.Lake Havasu
Lake Havasu is a large reservoir formed by Parker Dam on the Colorado River, on the border between California and Arizona. Lake Havasu City sits on the lake's eastern shore. The reservoir has an available capacity of 619,400 acre feet (764,000,000 m3). The concrete arch dam was built by the United States Bureau of Reclamation between 1934 and 1938. The lake's primary purpose is to store water for pumping into two aqueducts. Prior to the dam construction, the area was home to the Mohave Indians. The lake was named (in 1939) after the Mojave word for blue. In the early 19th century, it was frequented by beaver trappers. Spaniards also began to mine the areas along the river.Lower Colorado River Valley
The Lower Colorado River Valley ("LCRV") is the river region of the lower Colorado River of the southwestern United States in North America that rises in the Rocky Mountains and has its outlet at the Colorado River Delta in the northern Gulf of California in northwestern Mexico, between the states of Baja California and Sonora. This north–south stretch of the Colorado River forms the border between the U.S. states of California/Arizona and Nevada/Arizona, and between the Mexican states of Baja California/Sonora.
It is commonly defined as the region from below Hoover Dam and Lake Mead to its outlet at the northern Gulf of California (Sea of Cortez); it includes the Colorado River proper, canyons, the valley, mountain ranges with wilderness areas, and the floodplain and associated riparian environments. It is home to recreation activities from the river, the lakes created by dams, agriculture, and the home of various cities, communities, and towns along the river, or associated with the valley region. Five Indian reservations are located in the LCRV: the Chemehuevi, Fort Mojave and Colorado River Indian Reservations; at Yuma are the Quechan and Cocopah reservations.Ocotillo Wells, California
Ocotillo Wells is an unincorporated community in San Diego County, California. It is 3 miles (4.8 km) west of the Imperial County line on State Route 78 at an elevation of 163 feet (50 m). The name became official in 1962 when it was adopted for federal use by the Board on Geographic Names. A federally recognized variant name, Ocotillo, can cause confusion. The community of Ocotillo, in Imperial County, is only 29 miles (47 km) to the southeast.
The ZIP Code is 92004 and the community is in area code 760. The prefix for wired telephones is 767, which is shared with Borrego Springs.Palo Verde Mountains
The Palo Verde Mountains are a mountain range in northeastern Imperial County, California.The Palo Verde Mountains are located along the west side of the Colorado River in the Lower Colorado River Valley and Colorado Desert.Parker Valley
The Parker Valley is located along the Lower Colorado River within the Lower Colorado River Valley region, in southwestern Arizona and southeastern California.
Its natural habitats are within the Sonoran Desert (Arizona) and Colorado Desert (California) ecoregions. Riparian zone habitats on the river include Mesquite Bosques. The river has supported irrigated agricultural conversion of the valley's landscape.Riverside Mountains
The Riverside Mountains are a mountain range in Riverside County, California. The town of Vidal, California is located in the West Riverside Mountains.Sand to Snow National Monument
Sand to Snow National Monument is a U.S. National Monument located in San Bernardino County and into northern Riverside County, Southern California.
It protects diverse montane and desert habitats of the San Bernardino Mountains, southern Mojave Desert, and northwestern Colorado Desert.Santa Rosa Wilderness
The Santa Rosa Wilderness is a 72,259-acre (292.42 km2) wilderness area in Southern California, in the Santa Rosa Mountains of Riverside and San Diego counties, California. It is in the Colorado Desert section of the Sonoran Desert, above the Coachella Valley and Lower Colorado River Valley regions in a Peninsular Range, between La Quinta to the north and Anza Borrego Desert State Park to the south. The United States Congress established the wilderness in 1984 with the passage of the California Wilderness Act (Public Law 98-425), managed by the both US Forest Service (San Bernardino National Forest, 13,801 acres) and the Bureau of Land Management (58,458 acres ). In 2009, the Omnibus Public Land Management Act (P.L. 111-11) was signed into law which added more than 2,000 acres (8.1 km2). Most of the Santa Rosa Wilderness is within the Santa Rosa and San Jacinto Mountains National Monument.
The Santa Rosa Mountains have areas of cultural significance containing primitive trails, roasting pits, milling stations, rock shelters and examples of rock art. Native Americans have identified areas that are currently used for temporary habitation, resource collection and ritual hunting. Remains of historical early settlement and mining include quarry sites, mining prospects and water improvements associated with natural springs.Turtle Mountains (California)
The Turtle Mountains (Amat 'Achii'ar in the Mojave language), are located in northeastern San Bernardino County, in the southeastern part of California.
Colorado Desert Region