Castaic has the last traditional cattle roundup—with horses, lariats, and branding irons—in Los Angeles County. It has been held by the Cordova family since 1834, when the family first settled here. Members of the Cordova family were scouts for the U.S. Army during the Mexican War in 1846 and helped identify bodies during the St. Francis Dam disaster in San Francisquito Canyon in 1928. Operations scaled back in 1967 when the government seized around , including the ancestral ranch-house, for the planned Castaic Lake and dam. Geography Seismology The area is seismically active. On January 3, 2015, a pair of earthquakes of magnitude 3.1 (location: , depth: ) and 4.2 (location: , depth: ), respectively, were reported about north of Castaic. The epicenter was from Santa Clarita, California. Climate This region experiences hot and dry summers, and cool, moderately rainy winters. During the months of June though September, the average high temperature ranges from the 90s F (30s C) to above . According to the Köppen Climate Classification system, Castaic has a hot-summer Mediterranean climate, abbreviated "Csa" on climate maps. Demographics The 2010 United States Census reported that Castaic had a population of 19,015. The population density was . The racial makeup of Castaic was 13,607 (71.6%) White (57.1% Non-Hispanic White), 630 (3.3%) African American, 119 (0.6%) Native American, 2,162 (11.4%) Asian, 26 (0.1%) Pacific Islander, 1,466 (7.7%) from other races, and 1,005 (5.3%) from two or more races. Hispanic or Latino of any race were 4,716 persons (24.8%). The Census reported that 18,946 people (99.6% of the population) lived in households, 69 (0.4%) lived in non-institutionalized group quarters, and 0 (0%) were institutionalized. According to the 2010 United States Census, Castaic had a median household income of $106,538, with 7.0% of the population living below the federal poverty line. The population was spread out in age, with 5,761 people (30.3%) under the age of 18, 1,717 people (9.0%) aged 18 to 24, 5,144 people (27.1%) aged 25 to 44, 5,302 people (27.9%) aged 45 to 64, and 1,091 people (5.7%) who were 65 years of age or older. The median age was 35.6 years. For every 100 females, there were 101.2 males. For every 100 females age 18 and over, there were 99.8 males. There were 5,932 housing units at an average density of , of which 4,843 (84.2%) were owner-occupied, and 908 (15.8%) were occupied by renters. The