April Showers Help Boost Summer Reservoir Levels in the East Bay

Reservoir levels in the East Bay are above average for this time of year, signaling residents won’t have to conserve water – or incur extra drought-related charges – in the coming summer months.

Water storage levels are nearly full at 96%, according to the most recent East Bay Municipal Utility District water supply report. Nelsy Rodriguez, a public information representative for EBMUD, said that an early Sierra Nevada snowpack melt, in addition to a lot of April rain, helped refill reservoirs.

“We are in a strong position heading into summer. We are well above any potential drought trigger,” Rodriguez said. “We have enough storage now to meet our customers’ needs.”

The District, which serves 1.5 million residents in parts of Alameda and Contra Costa counties with drinking water, sources its water from the Mokelumne River watershed 90 miles away in the Sierra Nevada. An April snow survey showed Sierra Nevada snowpack levels were at their second-lowest ever recorded, prompting drought and wildfire concerns by officials.

A subsequent heatwave was good news for users like EBMUD, who use the snowpack to gauge how much water might be available throughout the hotter months.

“We had an early melt and that was great. It brought water down faster,,” Rodriguez said. “But that does highlight how complicated the water situation in California is getting.”

In January, California was officially declared free of drought conditions by the U.S. Drought Monitor, following nearly five dry years. That changed quickly, when experts at the National Integrated Drought Information System said in late April that 65% of the state was “abnormally dry,” including most of the Bay Area, even with rains being above average that same month.

NIDIS, which monitors drought conditions across the country, said that that designation was in part due to the record-breaking heat that melted the Sierra Nevada snowpack. The heat during March broke multiple Bay Area daily temperature records, according to the National Weather Service.

But, at least for now, EBMUD’s water supply is more than they have most years on average, according to Rodriguez.

“We typically don’t have such a strong heat wave in March, but with climate change, our traditional records are becoming less and less consistent, so things are changing on that front,” Rodriguez said. “The historical patterns are less reliable. We’re seeing more variability, including big swings between dry periods and intense storms.”

The Mokelumne watershed has recorded lower precipitation levels in recent months compared to historical data. Berkeleyside reported that the watershed saw 40.7 inches of precipitation last week, below the average of 47.25 inches, according to EBMUD.

The Contra Costa Water District, which provides water to other East Bay customers across eastern and central Contra Costa County, reported that 91% of its reservoir was full in April.