Entire town of Guerneville cut off by Russian River flooding during evacuation orders

Mitchell Crane canoes along a flooded Highway 116 east of Mays Canyon Rd. as flood waters rise in Guerneville, Calif., on Wednesday, Feb. 27, 2019. Mitchell Crane canoes along a flooded Highway 116 east of Mays Canyon Rd. as flood waters rise in Guerneville, Calif., on Wednesday, Feb. 27, 2019. Photo: Noah Berger / Special To The Chronicle Photo: Noah Berger / Special To The Chronicle Image 1 of / 92 Caption Close Entire town of Guerneville cut off by Russian River flooding during evacuation orders 1 / 92 Back to Gallery

The rains may have subsided but the Russian River near Guerneville in Sonoma County continues to swell over its banks and was at 42.5 feet at 9 a.m. Wednesday, 10.4 feet above flood stage.

"It came up super fast last night," Chris Baker, who is staying in a safe place in Guerneville through the flood, told SFGATE in an email. "You could almost watch it rising and it clearly caught out even experienced flood watchers. Unfortunately, several people have had cars/trucks swamped in our neighbourhood... beyond all the basements/lower levels that have taken on water."

The waterway is forecast to crest at 46 feet around 9 p.m. Wednesday, and the Sonoma County Sheriff's Office said the town of Guerneville is landlocked.

Last week, before the storm, the river was at about 13 feet.

The sheriff's office issued mandatory evacuations for 24 towns and neighborhoods along the river on Tuesday, and those who haven't left the area will be trapped as all roads in and out are flooded.

If the river rises to 46 feet, the area will see the worst flooding it has experienced in 24 years. Large swaths of the small town of Guerneville and the neighboring communities of Rio Nido and Monte Rio will be underwater.

More: What's expected to flood along the Russian River

The North Bay has sat under the bull's eye of a soaking storm for 48 hours. Relentless rain hammered Marin, Sonoma and Napa counties, inundating roads with water and pushing rivers, creeks and streams over their banks on Tuesday.

Some locations in Marin County, including San Anselmo and the Marin Civic Center, recorded more than nine inches of rain across two days.

On Tuesday, when the heaviest rain fell, Santa Rosa shattered its single-day rainfall record for the date with 5.66 inches. The old record was 5.23 inches in 1981. Santa Rosa's total for the storm is nearly eight inches.

The most rain was measured in the Russian River watershed. Venado, in the mountains just above Guerneville, recorded more than 20 inches. Nearby, a gauge at Lake Sonoma measured 10.79.

ALSO: When will it stop raining in the Bay Area?

Small streams and creeks are dropping, but those creeks mostly flow into the Russian River that's still swelling.

The Russian River is expected to go down slowly Wednesday night after reaching its peak, and its descent will sped up Thursday night. The river is expected to drop below flood stage on Friday morning.

In Napa County, a flood warning remains in effect for most areas along the rivers in the county until 8:30 a.m. Wednesday. It was at 26.14 feet at 5 a.m. and will crest at 26.6 later Wednesday. Minor flood stage on the Napa River starts at 25 feet and major is 28.

Bay City News contributed to this report.

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