Flood watch in North Bay as El Niño storm dumps heavy rain

Jim Wesley checks the water level as walks along the Russian River in Monte Rio. Jim Wesley checks the water level as walks along the Russian River in Monte Rio. Photo: Leah Millis Leah Millis, The Chronicle Buy photo Photo: Leah Millis Leah Millis, The Chronicle Image 1 of / 30 Caption Close Flood watch in North Bay as El Niño storm dumps heavy rain 1 / 30 Back to Gallery

The first of a pair of storms pounded Northern California on Thursday, bringing heavy bands of rain to the North Bay, causing minor flooding and mudslides, and raising the specter that the flood-prone Russian River might spill its banks.

The National Weather Service’s hazardous outlook remained in place for the most of the Bay Area as on-and-off downpours were forecast to continue Friday. Parts of Sonoma and Napa counties were expecting as much 4 inches of rain by Friday evening, igniting fear that a region thirsty for rain might get too much too fast.

The Russian River, with its long history of surging into streets and homes in the redwood-covered towns west of Santa Rosa, was expected to hit flood stage in Guerneville at 9 p.m Friday. River levels were expected to top out Saturday morning just shy of 3 feet above the 32-foot flood level, forecasters said — a cause for some worry but probably not enough of a deluge to cause major problems.

Video: North Bay Sees Wet Weather

“If you’re in that area, it’s a concern,” said Bob Benjamin, a forecaster for the National Weather Service. “But it doesn’t look like it’s going to be expansive flooding.”

Residents along the river, some of whom still remember the 1986 flood that submerged most of Guerneville, weren’t fretting Thursday — at least not yet.

“This one is going to be minor unless it continues past the weekend,” said Richard Evangelisti, 81, as he stood outside the True Value Hardware store across River Road from the roiling, brown stream of water that skirts his community.

RUSSIAN RIVER: Flood forecast at Guerneville gauge The image below is a real-time updated chart using automated forecast data. This image reflects the best information available at the time this article was loaded in your browser.



FLOOD IMPACTS: Complete NOAA River Conditions and flood impacts

His wife, Jacquie — also 81 and a descendant of the Guernes, who founded the town — has lived in Guerneville her entire life and knows enough to have stocked up with food, especially since flooding tends to block the roads she uses to get downtown.

“We’ve seen many floods,” she said, noting that she and her husband have generators, camping stoves and other equipment at the ready.

“On Valentine’s Day 1986, it was 48.5 feet and the water was up to here,” Richard added, holding his arm straight above his head. “You could row a boat in downtown Guerneville.”

Well upstream, water managers released supplies at Lake Sonoma earlier this week for the first time in five years to prevent the reservoir from filling up and having to discharge water when the storms arrive.

The Napa River in St. Helena was also projected to run slightly above flood stage Friday, peaking at around 3 p.m., according to the weather service. Navarro Creek in Mendocino County was expected to swell even higher above its banks between Friday morning and Sunday morning, but the rural waterway is far enough away from most homes as to not cause big problems.

The surging rivers are the result of an atmospheric river off the Pacific Ocean that forecasters say will keep parts of Northern California mostly wet through Monday. The North Bay is likely to bear the brunt of the system.

By Thursday evening, Santa Rosa had recorded 2.46 inches of rain, Point Reyes Station 1.77 inches and Napa an 1.97 inches. The hilly Sonoma County community of Venado had already logged 4.08 inches, with Mt. Tamalpais not far behind at 3.82 inches. The storm arrived later in San Francisco, dropping just 0.82 inches of rain by Thursday evening. The city was expected to pick up 1.5 inches through Friday.

Farther south, flash flood concerns through Niles Canyon delayed eastbound Altamont Commuter Express trains for up to 30 minutes through the evening as officials inspected tracks through the area where a mudslide derailed a train Monday night.

Conditions were forecast to mostly dry out by Saturday morning, according to the weather service, with a chance of showers on Saturday before another storm moves in Sunday.

Highway 1 along the coast was one of Thursday’s problem spots. The road was closed in Sonoma County at the community of Valley Ford and at Freestone Valley Ford Road because of flooding, according to the California Highway Patrol. There was also a tricky passage just south of the community of Tomales in Marin County because of a slide.

But the biggest threat remained the Russian River. Folks in Guerneville bought sandbags and prepared as best they could as the rain came down, though many longtime residents mostly shrugged.

Chris Reid, the manager at the True Value store, said he sold a pallet of sandbags in the morning, but didn’t expect a rush on flood supplies until things got more serious.

“We’ve sold some, but we probably won’t sell a lot of sandbags until it starts to flood,” Reid said. “If we hit flood stage, it’s probably only going to go a few feet over. We’d need four or five days straight of heavy rain for it to really get bad. I’ll be open as long as people can get here.”

Since the Russian River flooded during the El Niño deluge of 1997-98, more than half of the homes or rentals in the flood plain have been raised on stilts, providing better protection and greater assurances for those who live there. Still, the community is vulnerable.

Bobby Singh, 34, surveyed the raging waters in front of the house his wife’s grandmother has owned for 60 years.

“It’s kind of scary right now,” said Singh as he leaned over the soggy bank to see how a partially submerged dock built this past summer was faring. “If there are three more days of rain, the water is going to come.”

Peter Fimrite, Hamed Aleaziz and Kurtis Alexander are San Francisco Chronicle staff writers. Email: haleaziz@sfchronicle.com, pfimrite@sfchronicle.com, kalexander@sfchronicle.com Twitter: @haleaziz, @kurtisalexander, @pfimrite