A flood is an overflow of an expanse of water that submerges land. A flood may be caused by a heavy rainstorm, hurricane, river overflow, a high tide or large tsunami wave in the ocean, or dam failure. A flood can also be caused by blocked sewage pipes, storm drains, and other waterways. Floods are the most frequent type of disaster worldwide. They can occur in San Mateo County because it is located near rivers, dams, and the ocean. Insurance policies rarely offer coverage for floods.
Find out more about floods at Ready.gov.
Download floods checklist from NFPA.
Download Sandbag Resources and Directions.
Download Weather Saftey.