List of California floods

Remains of the St. Francis Dam in March 1928
The remains of the St. Francis Dam and reservoir floor, which killed more than 400 people after it failed in March 1928

All types of floods can occur in California, though 90 percent of them are caused by river flooding in lowland areas.[1][2] Such flooding generally occurs as a result of excessive rainfall, excessive snowmelt, excessive runoff, levee failure, tsunami, poor planning or built infrastructure, or a combination of these factors. Below is a list of flood events that were of significant impact to California.

A 2022 study found that Climate change in California will increase the extremity of water cycle events such as droughts and megafloods, greatly increasing the severity of future floods due to atmospheric rivers.[2] In part this is due to the expectation that the Sierra Nevada mountains, which typically retain water as snow, will no longer be as cold, reducing snowpack in favor or more runoff.[2] Thus water reserves do not accumulate, leading to drought conditions, even if there is more precipitation.[3]

  1. ^ "Historic Rainstorms in California". California Department of Water Resources. Archived from the original on 2007-08-24. Retrieved 2007-10-23.
  2. ^ a b c Huang, Xingying; Swain, Daniel L. (2022-08-12). "Climate change is increasing the risk of a California megaflood". Science Advances. 8 (32): eabq0995. Bibcode:2022SciA....8..995H. doi:10.1126/sciadv.abq0995. ISSN 2375-2548. PMC 9374343. PMID 35960799.
  3. ^ "Summary of Projected Climate Change Impacts on California – California Climate Adaptation Strategy". climateresilience.ca.gov. Retrieved 2024-07-03.