State facing ‘critically dry year’
Sierra snowpack at 59% of average; drought-like conditions in Bay Area
San Francisco is in the second-driest two-year period in recorded history, and the just ending rainy season is the third driest ever in California.
That sobering news came as the annual April 1 Sierra Nevada snowpack survey registered a disappointing 59% of the historical average, a low number for the second straight year.
That double whammy means the “D” word — drought — will likely be uttered more and more in the months to come and raises the possibility of future water use restrictions in the Bay Area, though local water districts on Thursday expressed hope those won’t be necessary.
Sean de Guzman, chief of snow surveys for the California Department of Water Resources, called the conditions “droughtlike” and said California’s reservoirs are at about half of their normal capacity.
“There is no doubt California is in a critically dry year,” Water Resources Director Karla Nemeth said in a statement. “State
agencies, water suppliers and Californians are more prepared than ever to adapt to dry conditions and meet the challenges that might be ahead.”
For now, that means asking Californians to be water efficient without requiring them to do so.
Bay Area meteorologist Jan Null said the rainfall over the bulk of the past two seasons is now the second driest in the 170 years on record in San Francisco, the only area in the Bay Area with uninterrupted records and the most historically accurate figure.
De Guzman said the statewide rainfall total over the past season was the third driest ever recorded.
According to Null, the 21-month total rainfall for San Francisco from July 1, 2019, through Wednesday was 20.46 inches. Null said that figure is 45% of the historical rainfall for that period and marks a deficit of 24.52 inches from the historical average.
The two-year rainfall total is barely more than a full rainfall total for one season, Null said. The average rainfall total in a normal year is
23.65 inches.
Null said the only 21-month period that has ever been worse was from 1975-77, when only 18.53 inches of rain fell.
Santa Clara Valley Water Board Chair Tony Estremera took those figures, as well as those at the U.S. Drought Monitor, and said Santa Clara County is now in a “moderate drought.”
He also expressed optimism, along with other water districts in the area, that preparation and knowledge gained from previous droughts should make 2021 bearable without a ton of sacrifice.
“Despite the lack of rain and snow, Santa Clara County’s water supply outlook appears adequate for the remainder of the year,” he said via email. “We anticipate sufficient supplies to meet demands in 2021. Our current groundwater levels are good, and we are maximizing our withdrawals of water from the Semitropic Groundwater Storage Bank near Bakersfield.
Valley Water is also actively working to purchase additional water supplies to help meet demands.”
Thursday’s measurement of the Sierra snowpack at 59% of historical average came a year after the 2020 survey was at 53%.
The April 1 reading is the most important one of the year for state water managers, because it signals the end of the rain and snow seasons.
The snowpack total is also down from a month ago, when on March 1 it was at 61% of its historical average. The few storms California has received this winter have brought more snow than rain, and that’s affected the state’s lakes and reservoirs, de Guzman said.
Shasta Lake is at 65% of its historical average and currently is only filled to 53% of its capacity. Lake Oroville is at 53% of its historical average for the date and is only 41% filled.
“We’re well below average with snow and precipitation, so we’d expect the runoff into the reservoirs to be at the same level,” de Guzman said.
Nevertheless, local water districts said they are also taking a wait-and-see approach on water restrictions.
“Overall, this year’s precipitation levels are disappointing but not as bad as 2013-2015,” spokeswoman Andrea Pook of the East Bay Municipal Utility District said in a statement. “The good news is that EBMUD has more water stored this time compared to the last drought. Our goal, always, is to refill our reservoirs — and though its less likely, it’s still possible.”
Water districts now will keep their eyes on how much of that snow actually runs off into streams and rivers and how much of it is absorbed into the vegetation.
“Right now, we feel we have enough to meet our customers’ needs,” Contra Costa Water District spokeswoman Jennifer Allen said. “It’s dry, no question. But that’s why we look at infrastructure and storage and prepare for the dry times.”