Rivers Threaten Towns in Northern California : Storms: Rain pushes water over banks, prompting flood warnings and evacuations. In Southland, cleanup continues.

The Russian and Petaluma rivers swelled over their banks and threatened to pour into rural towns as another wind-swept storm pummeled Northern California on Wednesday.

Flood warnings were posted in several counties north of San Francisco after hours of rain that triggered minor mudslides, school and road closures and scattered evacuations.

Meanwhile, in Southern California, crews continued to clean up flood damage at Camp Pendleton, while Marines and their families were given hepatitis shots out of concern over possible drinking-water contamination.

In Anaheim, three more houses were ordered evacuated Wednesday, bringing to 45 the number of upscale homes that have been temporarily abandoned after city officials said the rains reactivated an ancient landslide.

Mexican President Carlos Salinas de Gortari spent hours touring devastated neighborhoods of Tijuana, where at least 10 people died in mudslides and more than 20 others lost their lives in the worst flooding in 13 years.

In the tiny wine country town of Guerneville in Northern California, emergency crews braced for severe floods with the expectation that the Russian River would rise 10 feet above its banks by late Wednesday night, the National Weather Service said.

By midday, “minor overflows” were reported along stretches of the river and creeks, said Weather Service spokesman David Rosenberg. The Sonoma County Office of Emergency Services declared a state of emergency and evacuated an unspecified number of residents of a trailer park to a Red Cross center.

In Petaluma, residents of up to 100 houses along the Petaluma River were being evacuated late Wednesday as the river spilled over in some places. “It is over its banks, in the back yards of these home, through the side yards and running into the street,” said city spokeswoman Bonnie Bard.

The evacuations came after the Weather Service posted flash flood warnings in Napa, Sonoma, Marin and Lake counties.

“We’re getting things mobilized, because if there’s flooding it’s going to be worst in Guerneville,” said Sonoma County sheriff’s Lt. Bill Henson.

Trinity County officials also declared an emergency after the swelling Mad River cut off some outlets to about 350 residents in the hamlets of Ruth and Trinity Pines.

“We’re getting snowmelt plus heavy rain,” said sheriff’s Sgt. Dan Kartschner. “We’re having a pretty severe flooding situation here.”

In Marin County, Kent Middle School and Bacich Elementary School were closed as a precaution near Corte Madera Creek, school officials said. Branson School, a private school in neighboring Ross, also was closed.

In Kentfield, Jane Creighton was clearing gutters every few hours. “There’s so much rain coming down, it’s like a river running through the street,” she said.

Throughout the region, dozens of state routes and county roads were flooded or slicked by mud, closing some. The California Highway Patrol and sheriff’s offices said there were numerous traffic accidents, but no reported deaths.

The storm also brought gusty winds. Golden Gate Bridge officials warned that winds up to 50 m.p.h. were whipping across the span late Wednesday afternoon. The wind and driving rain delayed some incoming and outgoing flights at San Francisco International Airport for up to two hours, said airport spokesman Ron Wilson.

The Weather Service reported the region’s heaviest rain near Healdsburg in northern Sonoma County, which received seven inches during the 24-hour period ending at 2 p.m. Wednesday. Marin County’s highest rainfall total was 4.3 inches in Ross.

Weather officials predicted continued rain through today, but the weekend was expected to be clear.

In Southern California, bottled water was being dispensed at Camp Pendleton and emergency purification measures were being used. No dollar estimate of flood damage was available but it was expected to be in the millions because two bridges were washed out.

Mastery Gunnery Sgt. John Farrell, a base spokesman, said preliminary checks showed none of 70 flooded helicopters had sustained major damage. But he added that some helicopters were yet to be checked because the electronic gear needed to make the evaluation had not been returned to the base airfield.

“It just floated away,” he said.