Atascadero is a city in San Luis Obispo County, California, United States. It lies in the inland part of the Central Coast, between the Salinas River and the Santa Lucia Range, at the junction of U.S. Route 101 and State Route 41. Its population was 29,773 at the 2020 census.
The area has historical connections to the Salinan and Northern Chumash peoples. Publisher Edward Gardner Lewis founded the Atascadero Colony in 1913 as a planned agricultural community. Its development included orchards, a water system, a printing plant and a civic center. The colony also imposed racially restrictive property covenants. Atascadero incorporated as a city in 1979.
The former colony administration building serves as City Hall. Other institutions include Atascadero State Hospital, the Central Coast Zoo and the Atascadero Unified School District. Major employment sectors include healthcare and social services, retail, accommodation and food services, and education. Parks and open spaces include Atascadero Lake Park, Sunken Gardens and Stadium Park. The city has a Mediterranean climate, with hot, dry summers and cooler, wetter winters.
Name The Spanish name Atascadero means "bog" or "mire". The Obispeño name has been recorded as tsiskikiye, meaning "place of much water".
History Indigenous history Atascadero lies in an area associated with both Salinan and Northern Chumash histories. A cultural resources study prepared for the city's general plan describes historical Salinan occupation and the neighboring Obispeño Chumash to the south. It notes disagreement among ethnographers over the boundary between their territories and the possibility that boundaries changed over time. Salinan communities traded with the Yokuts to the east and Chumash communities to the south.
Oak woodlands, streams and the surrounding hills provided food and materials. The city's interpretation of Salinan history at Atascadero Lake describes the preparation of acorns with mortars and pestles and the use of willow, tule and fern roots in basketry. It identifies plants around the lake that Salinan people continue to use, including several species of oak, and also describes pine nuts, buckeye nuts and choke cherries as food resources.
Spanish colonization and the mission system disrupted Indigenous communities throughout the region. Introduced diseases reduced Salinan and Chumash populations, while livestock and colonial agriculture displaced hunting and gathering areas. After mission secularization in the 1830s, land grants transferred much of the territory to private owners.
Indigenous communities maintain connections with the area. The Salinan Tribe of San Luis Obispo and Monterey Counties has an office in Atascadero. The tribe describes its members' continuing hunting, fishing and gathering practices and its educational work to preserve cultural knowledge and protect ancestral lands. In the wider San Luis Obispo County region, the YTT Northern Chumash Tribe conducts language revitalization and cultural preservation work. Its language program provides learning opportunities, mentors and other resources for tribal members.
Ranchos and the planned colony During the Mexican period, Governor Juan Alvarado granted Rancho Atascadero to Trifon Garcia in 1842. The neighboring Rancho Asuncion was granted to Pedro Estrada in 1845. Land that became the Atascadero Colony subsequently formed part of J. H. Henry's ranch. In 1913, Edward Gardner Lewis, who had previously developed University City, Missouri, purchased land at $37.50 an acre and began promoting a planned settlement. He hired specialists in agriculture, engineering and town planning.
The colony's design combined residential lots, orchard tracts and a central business and civic district. Water lines and roads were installed as the property was subdivided. In her account of the settlement, colonist Marguerite Travis described a tent camp prepared for prospective buyers in 1914 and another for arriving settlers in 1915. Temporary facilities included shops, a laundry and a tent for public meetings and entertainment. Orchards included pears, peaches, apples, apricots and plums. A road through the Santa Lucia Mountains connected the colony to the coast at Morro Bay. Lewis's associated development company built the Cloisters hotel and beach cottages there.
The colony's property system excluded nonwhite residents. A 1914 deed restricted purchases to white people, and a 1920 deed also barred nonwhite occupancy and transfers. Such covenants were later made unenforceable by the 1948 Supreme Court ruling in Shelley v. Kraemer and prohibited by the Fair Housing Act of 1968. A 2023 county review of discriminatory property records identified these Atascadero deeds among the county's early examples.
The Printery, completed in 1915, housed the Woman's Publishing Company. It operated rotogravure presses that produced the Illustrated Review, women's magazines and newspaper inserts. Architect Walter D. Bliss designed the building, whose interior included murals by Ralph Holmes. The printing operation employed both men and women. The Atascadero News began publication in the Printery in 1916.
Civic buildings and later development The colony administration building, now City Hall, was constructed between 1914 and 1918. Designed by Bliss & Faville, it used locally manufactured bricks with concrete, steel and terra cotta. The building contained colony offices and later housed schools, county offices and veterans' facilities. It is California Historical Landmark No. 958. Its plan takes the form of a Greek cross, with central rotundas. The Colony Holding Corporation's bankruptcy in the 1920s ended its use as the corporation's headquarters.
The Carlton Hotel developed as a commercial and hotel building in the late 1920s. Its lower floor contained shops, with hotel rooms above. A renovation completed in 2004 restored much of the exterior and added a third floor. Atascadero State Hospital opened in 1954. Atascadero incorporated on July 2, 1979, as a general-law city.
A house in Atascadero was used to test inventor Harold Hay's Skytherm system of passive solar heating and cooling. Shallow, enclosed water ponds on the roof were alternately covered and exposed by movable insulation panels. Exposure to sunlight provided winter heating, while exposure to the night sky allowed summer cooling. The occupied experimental house was documented in the Los Alamos Scientific Laboratory's 1976 Pacific Regional Solar Heating Handbook.
On December 22, 2003, the magnitude 6.5 San Simeon earthquake severely damaged City Hall. The upper portion of the building had less reinforcement than the lower floors, complicating its repair. Restoration included rebuilding damaged upper masonry, strengthening the structure and reinstating historic architectural features. The city used a converted bowling alley as temporary City Hall during the repairs. After ten years of closure, City Hall reopened in August 2013. The Printery was also left vacant after the earthquake. A nonprofit foundation formed in 2015 and acquired the property in 2017 to undertake stabilization and restoration.
Geography Atascadero occupies part of the upper Salinas Valley, with the Salinas River to the east and the Santa Lucia Range to the west. Its landscape includes oak woodland, grassland and chaparral. The city's open spaces provide habitat within the developed area; Atascadero Lake is a stopover for migrating waterfowl.
According to the Census Bureau's 2020 gazetteer, Atascadero covers , including of land and of water. Water accounts for approximately 0.24 percent of the total area. The United States Geological Survey records an elevation of for the populated place.
The city's open-space system includes both public parks and land held by conservation organizations. Oak woodland and chaparral occur on hillsides around the developed valley, while riparian habitats follow the river and creeks. The biological resources assessment for the general plan identifies blue oak–foothill pine, coast live oak woodland, annual grassland and freshwater habitats among the area's vegetation communities.
Climate Atascadero has a Mediterranean climate, with hot, dry summers and cool, wet winters. Its inland conditions differ from those of the county's coastal communities. There is a substantial difference between daytime and nighttime temperatures. The water company's 2020 urban water management plan describes days with afternoon temperatures of followed by nights and early mornings in the range. Irrigation produces a strong seasonal variation in water demand: the plan reports summer monthly use at roughly three to four times winter use.
Demographics
The 2020 census counted 29,773 residents, compared with 28,310 in 2010. Figures before the city's 1979 incorporation refer to the unincorporated community.
2020 census The population density in 2020 was . The census reported that 98.7 percent of residents lived in households, 0.8 percent in noninstitutionalized group quarters and 0.5 percent in institutional group quarters. Of the population, 90.5 percent lived in urban areas and 9.5 percent in rural areas.
The median age was 41.5 years. Residents under 18 accounted for 20.9 percent of the population; 6.6 percent were aged 18–24, 26.7 percent were 25–44, 25.4 percent were 45–64 and 20.4 percent were 65 or older. There were 95.7 males for every 100 females, and 93.2 males for every 100 females aged 18 or older.
The census counted 21,947 White residents, 462 Black or African American residents, 361 American Indian and Alaska Native residents, 910 Asian residents, 38 Native Hawaiian and other Pacific Islander residents, 1,894 residents of some other race and 4,161 residents of two or more races. Hispanic or Latino residents of any race numbered 5,850, or 19.6 percent of the population.
There were 11,670 households, of which 30.0 percent included children under 18. Married-couple households accounted for 52.5 percent, cohabiting-couple households for 6.9 percent, female householders without a spouse or partner for 24.2 percent, and male householders without a spouse or partner for 16.4 percent. People living alone made up 23.7 percent of households; 10.8 percent consisted of someone aged 65 or older living alone. The average household size was 2.52. There were 8,030 family households, representing 68.8 percent of all households.
The city had 12,227 housing units, with an average density of . Of these, 11,670 units (95.4 percent) were occupied and 557 (4.6 percent) were vacant. Owner-occupied units accounted for 64.6 percent of occupied housing, and rented units for 35.4 percent. The homeowner vacancy rate was 0.9 percent and the rental vacancy rate was 4.4 percent.
2020–2024 estimates The American Community Survey (ACS) estimated a population of 29,712 for the 2020–2024 five-year period. Approximately 21.0 percent of residents were under 18 and 18.5 percent were 65 or older. The estimated median age was 40.4 years.
+ Racial composition, 2020–2024 ACS estimates Race Estimated population Percentage White alone 21,061 70.9% Black or African American alone 307 1.0% American Indian and Alaska Native alone 121 0.4% Asian alone 1,214 4.1% Native Hawaiian and other Pacific Islander alone 4 <0.1% Some other race alone 2,240 7.5% Two or more races 4,765 16.0% The ACS separately estimated that 6,692 residents, or 22.5 percent, were Hispanic or Latino of any race. These survey estimates cover a five-year period and are distinct from the 2020 census counts.