Less than a year after Gov. Jerry Brown declared the end of a statewide drought in April 2017, people are conserving less water and California’s water systems are once again vulnerable to drought.

Following an unusually dry winter, water conservation this year has fallen far below the mandated levels during the state’s recent multiyear drought, resulting in a combination of factors that may potentially lead to another drought.

“We only saved 0.8 percent of water in 2018 as compared to January 2013,” said George Kostyrko, director of the Office of Public Affairs of the California State Water Resources Control Board. “The board expressed concern about that because we need to have some level of conservation happening if we continue to have dry weather.”

Joe Charbonnet, a campus doctoral candidate in environmental engineering and a researcher at the Berkeley Water Center, said California has a “Mediterranean climate,” with especially heavy rainfall in “wet” months and very low rainfall in “dry” months.

Charbonnet said California’s rainfall conditions make the state particularly vulnerable to a drought when regular “wet” months suddenly show less rainfall than expected — especially as water consumption levels rise back up.

According to Doug Carlson, information officer for the California Department of Water Resources, water reservoir levels are filled to their averages, but another concern for the state’s water supply is the condition of the “snowpack” in the Sierra Nevada.

“The snowpack is the snow that essentially constitutes a high elevation reservoir that stretches across the Sierra Nevada. … On average, the state gets about 30 percent of its water from the melted snow,” Carlson said.

As of March 14, the water content of the snowpack is only 38 percent of the historical average on that date, compared to last year’s water content of 172 percent of the March 14 average, Carlson said.

According to Charbonnet’s research, enabling the use of stormwater as a freshwater source is a potential way to reduce vulnerability to drought. The challenge lies in removing the unwanted contamination in the water to reduce reliance on imported water.

“It’s really exciting that cities are starting to say that, ‘Wait, this is a new local source of water that we can get without importing it over long distances; let’s make use of it,’ ” Charbonnet said.

According to Charbonnet, the No. 1 use of electricity in California is pumping water from Northern California to Southern California. He cited this as an advantage of having a local water source for conservation efforts.

Carlson said the best way an individual can help is to “never let go of conservation as a California way of life.” Kostyrko similarly emphasized the importance of maintaining high reservoir levels unless Californians begin conserving again.

“It’s a lot less expensive to stretch a water supply than to create a new water supply,” Kostyrko said.