
The
environment of
California describes results of human habitation of the American State of
California.
History of environmental action

California's
Mediterranean climate makes vegetation susceptible to
wildfires through the dry summers. Aboriginal Californians used fire to control brush, promote growth of seed-producing plants important to subsistence, and perhaps as an aid to hunting wildlife. These periodic fires kept woodland areas relatively open until 20th century laws curtailed burning in an effort to protect structures.
European crops and livestock were introduced with
missions
Mission (from Latin ''missio'' "the act of sending out") may refer to:
Organised activities Religion
* Christian mission, an organized effort to spread Christianity
*Mission (LDS Church), an administrative area of The Church of Jesus Christ of ...
along the coast from
San Diego to
San Francisco Bay
San Francisco Bay is a large tidal estuary in the U.S. state of California, and gives its name to the San Francisco Bay Area. It is dominated by the big cities of San Francisco, San Jose, and Oakland.
San Francisco Bay drains water from a ...
through the late 18th and early 19th century. The
California Gold Rush
The California Gold Rush (1848–1855) was a gold rush that began on January 24, 1848, when gold was found by James W. Marshall at Sutter's Mill in Coloma, California. The news of gold brought approximately 300,000 people to California fro ...
caused explosive population growth making
San Francisco the only 19th century city west of
St. Louis, Missouri.
[Donley, Allan, Caro, and Patton ''Atlas of California'' (1979) pp.9-19] Water soon became the limiting factor for population growth, and early laws established
water rights for
irrigation and
hydraulic mining
Hydraulic mining is a form of mining that uses high-pressure jets of water to dislodge rock material or move sediment.Paul W. Thrush, ''A Dictionary of Mining, Mineral, and Related Terms'', US Bureau of Mines, 1968, p.560. In the placer mining of ...
. The
Great Flood of 1862
The Great Flood of 1862 was the largest flood in the recorded history of Oregon, Nevada, and California, occurring from December 1861 to January 1862. It was preceded by weeks of continuous rains and snows in the very high elevations that began in ...
washed
gravel
Gravel is a loose aggregation of rock fragments. Gravel occurs naturally throughout the world as a result of sedimentary and erosive geologic processes; it is also produced in large quantities commercially as crushed stone.
Gravel is classifi ...
displaced by gold mining downstream to cover riparian cropland and fill formerly navigable stream channels serving as transportation corridors to San Francisco Bay. The damage encouraged passage of water pollution control legislation, broadly regulating disposal of waste to include relatively innocuous materials like gravel. These California laws provided a template for the
United States Environmental Protection Agency National Pollutant Discharge Elimination System.
Population and transportation

California's aboriginal population of about 300,000 was distributed in relatively self-sufficient groups with subsistence resources on the coastal wetlands near the mouth of the
Smith River, along the
Klamath River and its interior wetlands, on the coastal wetlands surrounding
Humboldt Bay
Humboldt Bay is a natural bay and a multi-basin, bar-built coastal lagoon located on the rugged North Coast of California, entirely within Humboldt County, United States. It is the largest protected body of water on the West Coast between Sa ...
, on the wetlands surrounding
San Francisco Bay
San Francisco Bay is a large tidal estuary in the U.S. state of California, and gives its name to the San Francisco Bay Area. It is dominated by the big cities of San Francisco, San Jose, and Oakland.
San Francisco Bay drains water from a ...
and the rivers of the
California Central Valley
The Central Valley is a broad, elongated, flat valley that dominates the interior of California. It is wide and runs approximately from north-northwest to south-southeast, inland from and parallel to the Pacific coast of the state. It covers ...
, along the
Salinas River, and along the coastal wetlands between
Morro Bay and
San Diego Bay
San Diego Bay is a natural harbor and deepwater port located in San Diego County, California near the U.S.–Mexico border. The bay, which is long and wide, is the third largest of the three large, protected natural bays on California's of c ...
. Early European trade was by ship, but
El Camino Real extended northward along the southern California coast and through the
California Coast Ranges from
Mexico to San Francisco Bay to link individual missions with seaports. San Francisco Bay became the most important seaport for the gold rush and
ferries of San Francisco Bay carried trade between the seaport and mining areas. The
California Trail
The California Trail was an emigrant trail of about across the western half of the North American continent from Missouri River towns to what is now the state of California. After it was established, the first half of the California Trail f ...
became the first important land link between San Francisco Bay and the eastern United States during the gold rush and became the route of the
First transcontinental railroad
North America's first transcontinental railroad (known originally as the "Pacific Railroad" and later as the " Overland Route") was a continuous railroad line constructed between 1863 and 1869 that connected the existing eastern U.S. rail netwo ...
in 1869. The gold rush brought approximately 200,000 new residents to California, and 36% of Californians lived around San Francisco Bay by 1870.
Lumber from
coastal redwood forests was transported to San Francisco by ships. Redwood proved poorly suited for
railroad ties, so fast-growing
Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
n
eucalypts were widely planted to provide future supplies.
San Francisco Bay remained the focus of a railway network extending north and south until
Atchison, Topeka and Santa Fe Railway completed a transcontinental rail link to
Los Angeles and
San Diego in 1885. Eastbound rail shipment of
citrus began in 1890.
Petroleum was discovered in 1892, and the first
offshore drilling occurred at
Summerland Oil Field in 1896.
Hollywood
Hollywood usually refers to:
* Hollywood, Los Angeles, a neighborhood in California
* Hollywood, a metonym for the cinema of the United States
Hollywood may also refer to:
Places United States
* Hollywood District (disambiguation)
* Hollywood, ...
's
film industry and shift of the
United States Navy Battle Fleet home port to
San Pedro in 1919 accelerated growth of southern coastal cities to 36% of the state population by 1920.

As California petroleum production peaked, the United States Highway System of 1925 included routes paralleling older transportation corridors.
U.S. Route 101
U.S. Route 101, or U.S. Highway 101 (US 101), is a north–south United States Numbered Highway that runs through the states of California, Oregon, and Washington, on the West Coast of the United States. It is also known as (The Royal Roa ...
followed El Camino Real and extended through the redwoods to Humboldt Bay.
U.S. Route 99
U.S. Route 99 (US 99) was a main north–south United States Numbered Highway on the West Coast of the United States until 1964, running from Calexico, California, on the US–Mexico border to Blaine, Washington, on the U.S.-Canada border ...
extended northward from Los Angeles following railways through the Central Valley; and the
Lincoln Highway and
U.S. Route 66 followed the transcontinental rail routes from San Francisco Bay and Los Angeles, respectively.
Popularity of automobile travel encouraged construction of
California Route 1 connecting
California State Beaches,
U.S. Route 395 through the
Sierra Nevada
The Sierra Nevada () is a mountain range in the Western United States, between the Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primarily ...
, and the
Arroyo Seco Parkway as the first
freeway.
Smog
Smog, or smoke fog, is a type of intense air pollution. The word "smog" was coined in the early 20th century, and is a portmanteau of the words ''smoke'' and '' fog'' to refer to smoky fog due to its opacity, and odor. The word was then inte ...
was recognized as an
air pollution problem in 1954 as
Los Angeles Railway,
Pacific Electric Railway and
Key System
The Key System (or Key Route) was a privately owned company that provided mass transit in the cities of Oakland, Berkeley, Alameda, Emeryville, Piedmont, San Leandro, Richmond, Albany, and El Cerrito in the eastern San Francisco Bay Area fr ...
public transport facilities were dismantled during the
great American streetcar scandal. Southern California cities were home to 51% of Californians when the
Interstate Highway System arrived in 1959, while 26% lived around San Francisco Bay. Lincoln Highway became
Interstate 80
Interstate 80 (I-80) is an east–west transcontinental freeway that crosses the United States from downtown San Francisco, California, to Teaneck, New Jersey, in the New York metropolitan area. The highway was designated in 1956 as one o ...
, Route 66 became
Interstate 40, and
Interstate 5 extended from San Diego through Los Angeles and north up the
rain shadow
A rain shadow is an area of significantly reduced rainfall behind a mountainous region, on the side facing away from prevailing winds, known as its leeward side.
Evaporated moisture from water bodies (such as oceans and large lakes) is carrie ...
ed western side of the Central Valley and the eastern end of San Francisco Bay.
Modern commuter rail service includes
Bay Area Rapid Transit
Bay Area Rapid Transit (BART) is a rapid transit system serving the San Francisco Bay Area in California. BART serves 50 stations along six routes on of rapid transit lines, including a spur line in eastern Contra Costa County which uses ...
,
Caltrain,
Muni Metro,
Metro Rail (Los Angeles County),
San Diego Trolley,
Sacramento Regional Transit District,
Santa Clara Valley Transportation Authority light rail, and
Amtrak's ''
Pacific Surfliner'' and ''
Capitol Corridor''. In 2010, 9 million Californians (24% of the population) lived around San Francisco Bay and 21 million (57% of the population) lived in the southern coastal cities.
Water transfers

Unsuccessful gold prospectors soon recognized California's agricultural potential and their mining equipment began adjusting timing and location of stream flows to increase food production.
Mono Lake and
Tulare Lake shrank as flows were diverted to irrigation. Little Lake was drained to form the town of
Willits, California in 1874, and
Laguna de Santa Rosa was drained to bring rail service to Sonoma County. The
Klamath Project
The Klamath Project is a water-management project developed by the United States Bureau of Reclamation to supply farmers with irrigation water and farmland in the Klamath Basin. The project also supplies water to the Tule Lake National Wildlif ...
drained large shallow lakes for conversion to cropland in 1905. The
Potter Valley Project diverted water from the
Eel River to the
Russian River in 1906 to provide hydroelectric power to
Ukiah, California; and
Lake Pillsbury was formed behind Scott Dam in 1922 to increase summer flows allowing irrigation of Potter Valley.
California Water Wars opened with the
Los Angeles Aqueduct
The Los Angeles Aqueduct system, comprising the Los Angeles Aqueduct (Owens Valley aqueduct) and the Second Los Angeles Aqueduct, is a water conveyance system, built and operated by the Los Angeles Department of Water and Power. The Owens Valley ...
in 1913 as the first large-scale transfer of water from northern mountains to meet population needs of southern California's coastal cities.
Hetch Hetchy Aqueduct transferred water to San Francisco in 1932 after
John Muir's unsuccessful efforts to preserve
Yosemite National Park's
Hetch Hetchy Valley. The 1922
Colorado River Compact allowed completion of the
Colorado River Aqueduct to
Los Angeles in 1941.
[Donley, Allan, Caro, and Patton ''Atlas of California'' (1979) pp.142-145]
U.S. Bureau of Reclamation
The Bureau of Reclamation, and formerly the United States Reclamation Service, is a federal agency under the U.S. Department of the Interior, which oversees water resource management, specifically as it applies to the oversight and opera ...
public works projects included
Friant Dam
Friant Dam is a concrete gravity dam on the San Joaquin River in central California in the United States, on the boundary of Fresno and Madera Counties. It was built between 1937 and 1942 as part of a U.S. Bureau of Reclamation (USBR) water pr ...
on the
San Joaquin River in 1942 and
Shasta Dam on the
Sacramento River in 1945. These dams reduced winter flooding and summer salinity of the
Sacramento-San Joaquin Delta encouraging crop production on drained
wetlands
A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The ...
. The
Central Valley Project continued with
Folsom Dam on the
American River,
Trinity Dam on the
Trinity River, and
Oroville Dam on the
Feather River. Construction of the
California Aqueduct has been completed to Southern California except for a
Peripheral Canal which might restore pre-dam delta salinity concentrations.
A major fraction of water transferred to southern California is used for production of food. Irrigation
return flow
Return flow is surface and subsurface water that leaves the field following application of irrigation water. While irrigation return flows are point sources, in the United States they are expressly exempted from discharge permit requirements unde ...
s like the
New River may contain
pesticide
Pesticides are substances that are meant to control pests. This includes herbicide, insecticide, nematicide, molluscicide, piscicide, avicide, rodenticide, bactericide, insect repellent, animal repellent, microbicide, fungicide, and lampri ...
s and elevated concentrations of dissolved minerals, and may accumulate in
endorheic basins like
Kesterson Reservoir. The
Salton Sea was enlarged by diversion of water from the
Colorado River.
New environments

Aside from simple agricultural environments, water transfer has created a unique southern California
urban area. The relatively low urban
population density encouraged by automobile mobility features
edge effect habitats including a broad range of
landscaping plants.
Omnivore
An omnivore () is an animal that has the ability to eat and survive on both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize the nutr ...
s able to cross
street
A street is a public thoroughfare in a built environment. It is a public parcel of land adjoining buildings in an urban context, on which people may freely assemble, interact, and move about. A street can be as simple as a level patch of dirt, ...
s,
roads, and freeways thrive in this spatially fragmented habitat with dry season water available from landscape irrigation.
Columbidae,
Corvidae,
house sparrow
The house sparrow (''Passer domesticus'') is a bird of the sparrow family Passeridae, found in most parts of the world. It is a small bird that has a typical length of and a mass of . Females and young birds are coloured pale brown and grey, a ...
,
European starling and
gulls fly between isolated habitat segments, while
raccoons,
opossum
Opossums () are members of the marsupial order Didelphimorphia () endemic to the Americas. The largest order of marsupials in the Western Hemisphere, it comprises 93 species in 18 genera. Opossums originated in South America and entered North ...
s,
skunk
Skunks are mammals in the family Mephitidae. They are known for their ability to spray a liquid with a strong, unpleasant scent from their anal glands. Different species of skunk vary in appearance from black-and-white to brown, cream or ginge ...
s and
rat
Rats are various medium-sized, long-tailed rodents. Species of rats are found throughout the order Rodentia, but stereotypical rats are found in the genus ''Rattus''. Other rat genera include ''Neotoma'' ( pack rats), ''Bandicota'' (bandicoot ...
s travel under bridges and through culverts and
storm drain
A storm drain, storm sewer (United Kingdom, United States, U.S. and Canada), surface water drain/sewer (United Kingdom), or stormwater drain (Australia and New Zealand) is infrastructure designed to Drainage, drain excess rain and ground water ...
s. Animals killed during unsuccessful crossing attempts are a food source for scavengers also seeking garbage or food intended for pets or wild birds and
squirrel
Squirrels are members of the family Sciuridae, a family that includes small or medium-size rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and flying squirrels. Squ ...
s. Domestic
cats and
dogs kill small animals for recreation and have established
feral predator populations.
Coyote
The coyote (''Canis latrans'') is a species of canis, canine native to North America. It is smaller than its close relative, the wolf, and slightly smaller than the closely related eastern wolf and red wolf. It fills much of the same ecologica ...
s prey on these smaller predators.
[Wolch, West and Gaines ''Transspecies Urban Theory'' from Satiety and Space 1995. volume 13, pages 735-760]
Legislation
*
California Environmental Quality Act
*
California Proposition 23
*
California Proposition 50 (2002)
*
California Proposition 65 (1986)
*
Electronic Waste Recycling Act
*
Electronic Waste Recycling Fee
Organizations
*
California Air Resources Board
*
California Coastal Commission
The California Coastal Commission (CCC) is a state agency within the California Natural Resources Agency with quasi-judicial control of land and public access along the state's coastline. Its mission as defined in the California Coastal Act is " ...
*
California Coastal Conservancy
*
California Department of Pesticide Regulation The California Department of Pesticide Regulation, also known as DPR or CDPR, is one of six boards and departments of the California Environmental Protection Agency (Cal/EPA).
The stated mission of DPR is "to protect human health and the environmen ...
*
California Department of Toxic Substances Control
The California Department of Toxic Substances Control (or DTSC) is an agency of the government of the state of California. The mission of the DTSC is to protect public health and the environment from toxic harm. DTSC is part of the California En ...
*
California Environmental Protection Agency
*
California State Lands Commission
The California State Lands Commission is a unit of state government that is responsible for management and protection of natural and cultural resources, as well as public access rights, on some of California's publicly owned lands.
The members of ...
*
Water Education Foundation The Water Education Foundation is a nonprofit organization whose goal is to provide unbiased, balanced information on water issues in California and the Southwestern United States.
The Foundation's mission, since its founding in 1977, has been "to ...
Climate change
See also
*
CoolCalifornia.org
CoolCalifornia.org is a website for Californians with resources to help them reduce their impact on the environment and combat climate change. The website is geared towards different audiences, including: individuals, small businesses, local gover ...
*
Pollution in California
*
Ecology of California
The ecology of California can be understood by dividing the state into a number of ecoregions, which contain distinct Ecology, ecological community (ecology), communities of plants and animals in a contiguous region. The ecoregions of California ...
*
Environment of the United States
*
Environmental issues in the United States
*
List of Superfund sites in California
*
San Francisco Mandatory Recycling and Composting Ordinance
References
External links
Green CaliforniaCalifornia Department of Resources Recycling and Recovery(CalRecycle)
{{DEFAULTSORT:Environment Of California