SAN FRANCISCO – Creeks and rivers topped their banks, hundreds of homes were evacuated and several thousand people found themselves trapped in a rural hamlet as Northern California emerged Tuesday from yet another winter storm.
The atmospheric river of moisture that has saturated drought-parched ground with a series of drenching storms in recent weeks returned with a vengeance to the north on Monday after briefly focusing its fury on Southern California.
The downpours swelled watercourses that already teetered near or above flood levels and left about half of the state under flood, wind and snow advisories.
However, the storm system began to weaken late Monday night and was moving away after dumping 1.86 inches of rain in San Francisco, around 2 inches in much of the Central Valley and more than 7 inches in the mountains above Big Sur, the National Weather Service reported.
"Current radar and satellite data show the primary cold frontal rainband extending northeast to southwest through southern Santa Clara County and northern Monterey County, and weakening as it progresses inland," according to the forecast.
Scattered showers were expected to continue Tuesday, though.
On Monday, a levee break along the San Joaquin River prompted an evacuation order for about 500 people living in mainly ranch and farmlands near Manteca, San Joaquin County authorities said.
Some farmers took their tractors and other equipment to the levee to help shore it up, Manteca resident Dino Warda told television station KCRA.
Crews finally filled in the breach and at least temporarily halted the leak Monday night but the evacuation order remain in effect late Monday night and a flash flood warning was in effect into Tuesday.
Water had been backing up almost to the top of the San Joaquin River levees before the downpour.
"When the water gets that high and more water is coming, there is just too much pressure and levees can break," said Tim Daly, a spokesman with the San Joaquin County Office of Emergency Services.
In Monterey County, people living along a section of the Carmel River were told to leave, as were those in a neighborhood of Salinas near Santa Rita Creek and a few people in rural Royal Oaks, where a mudslide encroached on a home.
In Lake County, northwest of Sacramento, about 100 homes in two mobile home parks and nearby streets were ordered evacuated because nearby Clear Lake was a foot above flood stage, county Sheriff Brian Martin said.
More homes could be placed under evacuation order along the 75-mile shoreline as the water slowly rises, Martin said.
"It's very serious," he said Monday night of the potential for flooding. "There's going to be widespread property damage ... our ground's been saturated."
No injuries were reported.
Meanwhile, about 2,000 people in the remote community of Spring Valley were blocked in because one of two entrance roads to the hamlet washed away and mudslides closed the other, Martin said.
"Our deputies are basically hiking in and hiking out," Martin said.
Authorities hope to use a temporary bridge to reopen it in the next few days.
The Carmel River, which has flooded several times in the past month, was expected to rise to nearly 11 feet by Tuesday, which would be a moderate flood stage, while the Salinas River near Spreckels could reach nearly to the moderate flood stage of 26 feet by Tuesday night, which could inundate the Monterey-Salinas Highway, the Monterey Herald reported.
The Big Sur River reached its moderate flood stage of 10 feet Monday morning and was expected to crest at 12 feet, the paper reported.
"The ground is saturated, and all rainfall at this point is increasing not only the pooling along the lower-lying elevations but also the river levels," said Eric Ulwelling, a division chief with the Monterey County Regional Fire District.
A pre-evacuation advisory was issued for a community in Madera County after water discharges from Bass Lake were increased and threatened to swell rivers, officials said.
At the Don Pedro reservoir, which captures water from the Tuolumne River, a key tributary of the San Joaquin, operators had to open a spillway for the first time in 20 years.
In Napa County, water flowed into Lake Berryessa's unique spillway for the first time in more than 10 years.
The Monticello Dam Morning Glory Spillway, also known as the Glory Hole, operates similarly to a bathtub drain for the Northern California lake.
The last time it spilled over was in 2006.
Elsewhere, the water level kept falling at Oroville Dam, where a damaged spillway had raised major flood concerns and prompted the evacuation of 188,000 people a week ago.