 However, it generally remains 10 degrees hotter than the coastal plains below the Conejo Grade, in the communities of Santa Rosa Valley, Camarillo, and Ventura among others.The 2010 United States Census reported that the self-incorporated portion of Westlake Village, on the Los Angeles County side, had a population of 8,270.The population density was 1,502.4 people per square mile (580.1/km²).