The Northridge earthquake caused high shaking intensities for several million persons in the northern Los Angeles region, centered in the San Fernando Valley. Fire protection for the heavily damaged area is furnished primarily by Los Angeles City Fire Department and, to a lesser extent, Los Angeles County, Santa Monica, and other departments. The earthquake resulted in about 110 fires, about 80% of which were structure fires. Of these, most were in single-or multi-family dwellings. All of the initial fires were out before noon despite impaired communications, wide-scale failure of firefighting water supply in large parts of the San Fernando Valley, and other problems. Alternative water supplies, such as backyard swimming pools, were employed in some cases. Mutual aid was requested by fire departments in the affected area, but resources from outside the Los Angeles metropolitan area were not required.