Hydrologic Conditions: Elsewhere in the Southwest, April-May 2016

Lake Oroville

The storage level in Lake Oroville, the primary storage reservoir for California State Water Project, continues to increase. On April 1st, the reservoir held 3,070,013 AF—which is 87% of the total capacity or 114% of the historical average for the date. As of May 1st it had increased to 3,403,047 AF—which is 93% of the total capacity or 118% of the historical average for the date. The storage level exceeds the 1982-83 wet period (see chart).

Oroville chart 05-2016

After a nearly dry February, March storms brought a deluge of water to Northern California nearly filling Lake Oroville, Shasta and Folsom and prompted DWR to increase the SWP allocation to 60%, exceeding the average allocation of 49% from the previous 10 years (2006-2015), but still falling below the long-term average of 69% from 1990 to current. Despite the increased SWP allocation, DWR warns that “the state’s historic drought is far from over.” The department is preparing for the possibility of a dry 2017.