Chumash/pre-colonial period Simi Valley's name is derived from the Chumash word Shimiyi, which refers to the stringy, thread-like clouds that typify the
region. The name could have originated from the strands of mist from coastal fog that move into the
Oxnard Plain and wind their way up the
Calleguas Creek and the Arroyo Las Posas into Simi Valley. The origin of the name was preserved because of the work of the anthropologist
John P. Harrington, whose brother, Robert E. Harrington lived in Simi Valley. Robert Harrington later explained the name:
"The word Simiji in Indian meant the little white wind clouds so often seen when the wind blows up here and Indians living on the coast, would never venture up here when those wind clouds were in the sky. The word Simiji was constructed by whites to the word Simi. There are other explanations about the name Simi, but this one was given to me by my brother who worked over 40 years for the Smithsonian Institution and it seems most plausible to me". Three Chumash settlements existed in Simi Valley during the Mission period in the late 18th and early 19th century: Shimiyi, Ta'apu (present-day
Tapo Canyon), and Kimishax or Quimicas (
Happy Camp Canyon west of
Moorpark College). There are many Chumash cave paintings in the area containing pictographs, including the
Burro Flats Painted Cave in the Burro Flats area of the
Simi Hills, located between the Simi Valley,
West Hills, and
Bell Canyon. The cave is located on private land owned by NASA. Other areas containing Chumash Native American pictographs in the Simi Hills are by Lake Manor and
Chatsworth.
The Rancho period was granted in 1795 to the
Pico family of California. Pictured is the
Simi Adobe. The first Europeans to visit Simi Valley were members of the Spanish
Portolá expedition (1769–1770), the first European land entry and exploration of the present-day state of
California. The expedition traversed the valley on January 13–14, 1770, traveling from
Conejo Valley to San Fernando Valley. They camped near a native village in the valley on the 14th.
Rancho Simí, also known as Rancho San José de Nuestra Señora de Altagracia y Simí, was a
Spanish land grant in eastern
Ventura and western
Los Angeles counties granted in 1795 to Santiago Pico. After Santiago Pico's death in 1815, the Rancho was regranted to Santiago's sons Javier Pico and his two brothers, Patricio Pico and Miguel Pico, members of the prominent
Pico family of California. It was the largest Spanish or Mexican land grant given in Ventura County, and one of the largest given in California. The
Simi Adobe-Strathearn House, later the home of Robert P. Strathearn and family, served as the headquarters of the rancho.
José de la Guerra y Noriega, a Captain of the
Santa Barbara Presidio, who had begun to acquire large amounts of land in California to raise cattle, purchased Rancho Simí from the Pico family in 1842. After Jose de la Guerra death in 1858, the sons of Jose de la Guerra continued to operate the ranchos. The end of their prosperity came when several years of drought in the 1860s caused heavy losses. In 1865, the De la Guerras lost the ownership of El Rancho Simí excluding the Rancho Tapo. El Rancho Tapo was part of the original 113,009-acre Rancho Simí grant, but sometime around 1820–1830, the Rancho Tapo came to be thought of as a separate place within Rancho Simí. The earliest Anglo American ranchers showed up in Simí Valley in the late 1860s into the 1870s. Charles Emerson Hoar was given the title of "first American farmer" by early Simí historian Janet Scott Cameron. He had purchased the Hummingbird's Nest Ranch in the northeast corner of the Valley, and he leased land from the new owners of the Simí Rancho for raising sheep, already a proven way of making a living. Much of the Simí Rancho land continued, as in Spanish days, to be used for raising sheep, cattle and grain. Wheat was more likely to prosper here than in the rest of the county, being free of
wheat leaf rust, a fungal disease. Barley soon became the predominant grain crop. Agriculture and ranching dominated the landscape through the 1950s. Citrus, walnuts and apricots were all grown in Simi Valley. In the early 1960s modern residential development began to take place.
Modern residential development When Simí was an agricultural community, there were ranch houses that dotted the Valley. Four distinct communities also were located in the Valley (see 'Four Communities of Simi Valley' section below) prior to modern residential development. Though 1957 and 1958 brought the first 'tract' housing developments when the Dennis and Ayhens, Wright Ranch and Valley Vista tracts were built, the tremendous 'boom' in residential development took place beginning in 1960. The population which was 4,073 in 1950 doubled to 8,110 in 1960. By 1970 the population in Simi is reported by the census as 59,832.
Four communities prior to modern residential development The pioneers arrived in the late 1860s – 1870s and ever since, this has been 'The Valley of Simi.' But, not all the communities in the valley were known as 'Simi.' There was the township of Simi (known as 'Simiopolis' for about a six-month period in 1888). In the valley there were also the communities of Santa Susana, Community Center and the Susana Knolls (known first as Mortimer Park) at different points in time.
Simi – In late 1887–1888, the incorporation of Simi Land and Water Company came about. El Rancho Simí was divided into ranches and farms by that corporation, and advertised for sale to midwestern and New England states. An investor group, the California Mutual Benefit Colony of Chicago, purchased land and laid out a townsite (located between First and Fifth Streets and from Los Angeles south to Ventura Ave), named it 'Simiopolis' and shipped twelve pre-cut, partially assembled houses from a lumberyard in Chicago via rail to Saticoy, then brought by wagon to Simi. These are known as 'colony houses.' This was the first 'neighborhood' in Simi. Stores sprung up on Los Angeles Ave, and the first Simi School was built in 1890 on Third and California Streets, and was used until Simi Elementary was built in the mid-1920s.
Santa Susana – In 1903 the
Santa Susana Train Depot was built, and the railroad was complete through Simi Valley, except for the tunnel, which was completed in 1904. A small business community grew up near the Santa Susana Train Depot, which was located on the north side of Los Angeles Ave, just east of Tapo Street. Over time residential developments followed and the town of Santa Susana was born. The Depot was moved in 1975 by Rancho Simi Recreation and Park District to its current location off of Kuehner.
Community Center – In 1922 L.F. Roussey laid out the small development which became known as Community Center. The driving force behind this development was the need for a High School in Simi Valley, as well as an elementary school in a more central location in the valley. The first graduating class from Simi High School was 1924, Simi Elementary was completed in 1926, The Methodist Church (which is now the Cultural Arts Center) was built in 1924. Numerous houses were built in Community Center in the 1920s and 1930s. The Simi Valley Woman's Club was located there as well (the building which served as the clubhouse for the Woman's Club was moved from the town of Simi). The Woman's Club club house was used by many individuals and organizations as a community meeting place.
Mortimer Park (the Susana knolls) – The area that is now the Knolls was a nearly that was purchased by Mr. and Mrs. Lewis T. Mortimer in the early 1920s. They planned on selling the lots for cabins, or vacation homes. The lots were very small (30 x 50 feet), and the Mortimers did not take the mountainous nature of the land into account, so quite often the lots were not buildable. Oftentimes several lots were needed to build structures. In 1944 the Garden Club, an active community organization in the area petitioned the county supervisors to change the name of Mortimer Park to the Susana Knolls. ''The first attempt to incorporate the towns of Simi, the area known as Community Center (93065) and Santa Susana (93063) in 1966 was unsuccessful. The second attempt in 1969 was successful, with residents voting 6,454 to 3,685 in favor of incorporation. 59% of eligible voters turned out for this vote. Susana Knolls is an unincorporated area of the Valley. Voters also voted whether to call this newly incorporated city 'Santa Susana' or 'Simi Valley.' The name Simi Valley garnered 2,000 more votes than Santa Susana. when it powered the city of
Moorpark (the government owned
BORAX-III reactor had previously powered
Arco, Idaho for around an hour in 1955). The last nuclear reactor operated at SSFL in 1980 and the last rocket engine was produced in 2006. The SSFL has been closed to development and testing. The site is undergoing investigation and removal of the nuclear facilities and cleanup of the soil and groundwater. The Boeing Company, the US DOE, and NASA are responsible for the cleanup. In July 1959, the
Sodium Reactor Experiment suffered a serious incident when 13 of the reactor's 43 fuel elements partially melted resulting in the controlled release of radioactive gas to the atmosphere. The reactor was repaired and returned to operation in September 1960. The incident at the Sodium Reactor Experiment has been a source of controversy in the community. Technical analysis of the incident intended to support a lawsuit against the current landowner (
The Boeing Company) asserts the incident caused the much greater release of radioactivity than the accident at
Three Mile Island. Boeing's technical response concludes the monitoring conducted at the time of the incident, shows only the allowable amount of radioactive gasses were released, and a Three Mile Island-scale release was not possible. The case was settled, it is reported, with a large payment by Boeing. In September 2009, The U.S. Department of Energy sponsored a public workshop where three nuclear reactor experts shared their independent analysis of the July 1959 incident. The Santa Susana Field Laboratory also hosted the
Energy Technology Engineering Center. The center performed the design, development and testing of liquid metal reactor components for the
United States Department of Energy from 1965 until 1998. The Santa Susana Field Laboratory includes sites identified as historic by the
American Institute of Aeronautics and Astronautics and by the
American Nuclear Society. The
National Register of Historic Places listed
Burro Flats Painted Cave is located within the Santa Susana Field Laboratory, on a portion of the site owned by the
U.S. Government. The drawings within the cave have been termed "the best preserved Indian pictograph in Southern California". in background ==Geography==