Federal researchers: Drought is over in Bay Area

The researchers who assemble the weekly U.S. Drought Monitor map have acknowledged what most of us have felt in our bones (and our rain buckets) for several weeks: The drought is over.

Future dry-ups are highly possible in this era of extreme weather boomeranging, but as of this week, when the most recent map was released, all nine Bay Area counties have moved out of the monitor’s color-tiered drought categories.

Or almost. About 8% of Napa County’s remains “abnormally dry” — the monitor’s mildest level of impact. But they are rugged, mostly unpopulated areas. In fact, the Drought Monitor estimates zero people live in them. The rest of the Bay Area, including all of Sonoma County, is officially drought-free for the moment.

The last time any portion of Sonoma County was not officially in drought was Feb. 11, 2020. And the last time the county was 100% drought-free was three weeks before that.

Just a week ago, much of Sonoma and Mendocino counties, most of Napa and all of Lake were categorized as abnormally dry. But then more rain fell, the tail end of an extraordinarily wet winter in the North Bay.

Since Oct. 1, the official beginning of the wet season, Santa Rosa has received 42.7 inches of rain, according to National Weather Service meteorologist Sarah McCorkle. The average here for Oct. 1 through March 31, she said, is 27.8 inches. The Sierra snowpack is at record levels, and local reservoirs are close to capacity.

At Lake Sonoma on Friday, the problem wasn’t too little water, but too much. A cluster of logs was blocking the outlet next to Warm Springs Dam, and crews were working to unjam them.

As of March 26, Lake Sonoma was at 270,000 acre-feet and Lake Mendocino was around 92,000 acre-feet, according to data from Sonoma Water. Both of those are well above water supply targets. Lake Pillsbury was just under 60,000 acre-feet on March 25; that’s 87.4% of the reservoir’s target supply.

“It’s good news that we’ve had a really wet year,” Sonoma County Supervisor Chris Coursey said. “It explains the webs between my toes. It’s good for anybody who needs water to live — and that’s everybody.”

At the same time, Coursey cautioned that it’s no time to abandon the useful, water-saving habits most of us have acquired over the past few years, like taking shorter showers and limiting how much you water your landscaping.

“I’ve had a bucket next to my sink in the bathroom for a long time.” Coursey said. “It takes the water a while to warm up. Last year or the year before, I put in a completely drought-tolerant garden in the backyard. No grass. I live in a small house, and I’m trying to do my part.”

That hesitancy to wave a green flag on water usage is echoed by leaders from California Gov. Gavin Newsom on down, an indication of the hardships that resulted from three consecutive parched years.

A year ago, 96.5% of Sonoma County was in the U.S. Drought Monitor’s “extreme drought” tier. By the start of the water year, the entire county had eased into “moderate drought” conditions, but no one could have imagined the intermittent deluge to come, with 15 atmospheric rivers passing over the state.

Locally, that long-awaited precipitation has brought relief to most residents, but also a slew of weather-related deprivations, including downed trees, flooded roads, power outages and several deaths.

In light of changing conditions, the Sonoma County Department of Emergency Management expects to make a formal presentation before the Board of Supervisors on April 18, seeking to suspend the county’s drought emergency resolution that has been in effect since April 27, 2021.

“We still consider that we’re kind of in drought,” said Sam Wallis, community alert and warning manager for the Department of Emergency Management. “But obviously the reservoirs are pretty much full, the rivers are full. We’ll continue to monitor the situation. But for the time being, we have to be frank and recognize things have improved substantially.”

Dropping the drought emergency proclamation is unlikely to have direct, immediate effects on the county’s residents. The resolution was primarily a tool for assessing drought impacts, and for coordinating any mutual aid that may have come from the Governor’s Office of Emergency Services in response to the climate crisis.

The message was more tangible when the City of Santa Rosa ended its own emergency drought declaration on March 15. That one rolled back city-ordered water conservation measures such as limits on when residents can water their lawns.

On the other hand, everyone in California is still required to adhere to statewide measures until December, unless the State Water Resources Control Board elects to drop its order before then. Those rules prohibit Californians from washing vehicles without a shut-off spray nozzle, washing down hard surfaces like driveways or sidewalks, filling decorative fountains or ponds without a recirculation pump and watering lawns in commercial, industrial or institutional areas.

But the brimming water sources are already a welcome sight to North Bay agricultural interests, who faced three years of curtailed access and diminished output.

“It’s very, very hard,” said Dayna Ghirardelli, executive director of the Sonoma County Farm Bureau. “For the most part, in our area, we rely heavily on storing water that falls from the sky. There are a lot of operations in this area that, without that rainfall, it’s detrimental to their businesses, and to their resources on the ground.”

The heavy rains and frosty mornings have presented their own challenges, Ghirardelli said. For example, this would normally be the time ranchers put cows out to pasture for graze for food. But in some places, it’s still way too wet, she said, and the freezes have hurt the grasses.

Still, the ag sector is thrilled to see an official end to drought conditions — even if growers have become more cautious as the climate has become harsher.

“This a great reprieve,” Ghirardelli said. “But there’s still fear, because we’re likely to go back to where we were at some point, for various reasons — between weather, drought, lack of storage, mismanagement of water in other areas. Ultimately, everyone has a sigh of relief. But it won’t change our demeanor.”

The U.S. Drought Monitor has been redrawing its weekly map since 2000, but it has taken on new resonance in recent years with a surge in dramatic weather events such as drought, wildfires and hurricanes.

It’s far more sophisticated than a precipitation chart, according to Curtis Riganti, who was responsible for shading the most recent map. He works at the National Drought Mitigation Center in Lincoln, Nebraska, which pools the data in conjunction with the National Oceanic and Atmospheric Administration and the U.S. Department of Agriculture.

“We’re basically contouring the likelihood of severe weather,” Riganti said. “And we’re doing it by historical percentile, based on the climatology of each area. What constitutes drought in Lincoln is not the same as Denver or Miami.”

The color lines on the Drought Monitor map are “human-drawn,” Riganti said, not algorithm-generated. The consortium relies on data that includes snowpack levels, groundwater and stream flow measurements, remote sensing data from satellites, precipitation deficits ranging from several weeks to several years and “atmospheric thirst for water.”

That’s the science behind the map. The end product is easy to interpret. Darker colors represent more intense levels of drought. And the Bay Area has finally gone white — white as the snow piled 60 feet high in the Sierra Nevada.

You can reach Phil Barber at 707-521-5263 or phil.barber@pressdemocrat.com. On Twitter @Skinny_Post.