Surveying Flash Flood Response in Mountain Streams

During the winter season of 2005, Southern California was besieged by a series of heavy precipitation events that caused widespread flash flooding, mud slides, debris flows, and significant damage. The first event began in December (28 December 2004 to 4 January 2005), triggered mudflows and flooding in the San Bernardino Mountains, and produced a record daily rainfall total for the city of Los Angeles. The second period of heavy rainfall occurred in January (7–12 January 2005) and was widespread, extending from west of Santa Barbara to the San Bernardino Mountains in San Bernardino County and to the south including San Diego County. The peak rainfall total during the January 2005 event exceeded 700 millimeters (30 inches) over the six-day period. Impacts included the disastrous La Conchita landslide in Ventura County, which killed 10 people and destroyed or damaged over 35 homes.