What a difference a month can make.
During the first manual measurement in January, the Department of Water Resources revealed a dire snapshot of water content of the Sierra Nevada snowpack, which was found to be just 6 inches — only 53 percent of the early-January average. Nearly one month later, things are looking up as the latest snow survey conducted at the Philips Station in the Sierra Nevada range revealed a snow water equivalence of 28.1 inches.
“We’ve got a very good snowpack, a very robust snowpack on the ground right now,” said chief of the California Cooperative Snow Surveys Program Frank Gehrke, who conducted the survey on Thursday.
This snow water equivalence is not only a significant increase from January’s reading, but it is also more than the average that has been measured at Phillips since 1964, which is 18.4 inches.
Snow water equivalence roughly equates to the amount of water that would hypothetically result if the entire snowpack suddenly melted. The snowpack on average provides about 30 percent of California’s water once it melts in the spring and early summer. The greater the snowpack water content, the greater the likelihood California’s reservoirs will receive ample runoff as the snowpack melts to meet the State’s water demand in the summer and fall.
According to DWR’s electronic readings from 101 stations throughout the Sierra Nevada Thursday, water content came in at 26 inches for the northern Sierra snowpack, 32 inches for the central Sierra snowpack, and 32 inches for the southern Sierra snowpack. These readings are 144 percent, 173 percent, 200 percent of the multi-decade average for the date, respectively. Statewide, the snowpack had a snow water equivalent of 31 inches, which is 173 percent of the Feb. 2 average of 18.1 inches. On Jan. 1 before a series of storms, the snow water equivalent of the statewide snowpack was 6.5 inches, which was just 64 percent of the New Year’s Day average.
DWR said that the first four months of the 2017 water year, which began in October, were wet due to atmospheric river storms and rainfall from lesser storms that drenched the state. However, while the latest reading reflects an exceptionally wet year, storms can cease. For example, after the previous drought declaration ended in March 2011, severe drought returned, leading to the driest four year period in California’s history.
“In the last 10 water years, eight have been dry, one wet, one average,” said State Climatologist Mike Anderson. “Hopefully this year will end up being wet, but we cannot say whether it will be one wet year in another string of dry ones.”