Last month, California emerged from drought conditions for the first time since December 11, 2011, according to the U.S. Drought Monitor, breaking a 376-week streak.
In response, the California Department of Water Resources increased the amount of water delivered from its State Water Project storage system from 35 percent of contractor requests, which it announced in February, to 70 percent.
So can La Jolla residents similarly up their water use?
That’s the last thing they should do, experts say, and it explains why munipical drought restrictions — three-day weekly lawn-watering, recycled water for ornamental fountains, water served in restaurants only upon request — have not and will not be lifted.
San Diego’s total average rainfall is projected to decrease in the long-term, explained Scripps Institution of Oceanography climate researcher Julie Kalansky, with as much as an 8 percent rain reduction in the next 30 years.
Kalansky was the lead author of the San Diego section of California’s Fourth Climate Change Assessment. Published in August 2018, the report summarized recent climate research, including work sponsored by the California Natural Resources Agency and California Energy Commission.
According to Kalansky, it’s “hard to say” whether any one singular weather event — such as this winter’s unusually heavy rain — results from man-made climate change, “but what we’ve experienced recently is representative of what the climate projections are predicting.”
Those projections, Kalansky said, show wet seasons that are shorter and dryer, yet punctuated by more severe downpours. (The average wettest day every five years is expected to be between 10-25 percent wetter.) This is largely due to more intense atmospheric rivers — filaments of dense moisture transported from the tropics.
At the same time, however, the swings between wet and dry years are going to get “much bigger,” Kalansky said, “with more frequent and intense dry events” as well.
So no, California’s drought is not permanently over. Kalansky said the next one is not only “inevitable,” but will probably be worse because hotter average temperatures — up between 5 to 10 degrees by the end of the 21st century — will dry up vegetation faster.
In other words, more floods and fire risk.
But there is some good news amid all this bad. On Feb. 28, 2008, then-Governor Arnold Schwarzenegger set a 2020 goal to reduce per-capita water use by 20 percent.
“We blew that away,” said San Diego County Water Authority principal water resources specialist Jeff Stephenson, reporting that the County’s water usage is down more than 40 percent since then.
“Going forward, I anticipate water use staying far beneath the levels it used to be,” Stephenson said. “It’s become a lifestyle for most people.”
Even though San Diego’s population is projected to increase 25 percent by 2050 (from 3 million to 4 million, according to 2017 projections from the California Department of Finance), Stephenson said that, according to the Water Authority’s assessment in the 2015 Urban Water Management Plan, “water supplies will meet demands through the year 2040 in its service area.”