Dry spells come and go in California, where the difference between a wet and dry year often depends on how much precipitation the state gets from just a few storms during winter.
During the period of recorded water history, California's most significant statewide droughts were 1929-34, 1976-77, 1987-1992, 2007-09 and the recent five-year drought, according to the state department of water resources. The 2007-09 drought was was the first for which a statewide emergency was declared.
Note that the measurements cover only a small part of California history because rainfall data and other information did not begin until around the start of the 20th Century.
These photos, including images of the state's major reservoirs, show changing conditions dating from the mid-1970s through January 2017, one of the state's wettest months in years.