New Storm Brings Flooding to N. California : Weather: The latest downpour prompts evacuations in several communities. In the Southland, the cleanup continues.

Overflowing rivers began flooding several towns as a powerful new storm hammered Northern California with intense rain Wednesday night, but forecasters said the heavy weather should bypass the already sodden Southland.

Officials in Sonoma and Trinity counties declared states of emergency as the floodwaters continued to rise, and flash-flood warnings in Sonoma, Napa, Marin and Lake counties prompted emergency evacuations in several communities.

Meanwhile, work crews in Southern California took advantage of the first real break after two weeks of stormy weather, cleaning up the flood damage at Camp Pendleton while Marines and their families were given hepatitis shots out of concern that drinking water on the base may have become contaminated.

Three more houses were ordered evacuated in Anaheim on Wednesday, bringing to 45 the number of upscale homes that have been vacated after city officials said the rains apparently had reactivated an ancient landslide.

South of the border, Mexican President Carlos Salinas de Gotari spent hours touring devastated neighborhoods of Tijuana, where catastrophic floods left 31 dead and thousands homeless.

Salinas promised to make federal land and loans available to help relocate residents from the canyons where most of the deaths and destruction occurred.

The federal land that probably will be donated totals 165 acres and is in the Ejido Matamoros area southeast of Tijuana’s center, said Victor Hermosillo, public works secretary for the state of Baja California. The federal government will turn over the parcel to the state for development.

Salinas also announced that there will be federal aid for the Baja state as it begins the monumental task of rebuilding roads, repairing and improving flood drainage and giving aid to the thousands of flood victims who have lost all their possessions.

“I have come to know personally what Baja Californians have known: There has been no precedent in the past half century� for the rain and destruction visited on the area, Salinas said. “Baja Californians can count on the support of the president of the republic.�

Tijuana Planning Director Diego Moreno said Wednesday that the city plans to start relocating 1,500 families to federal and state land within a few weeks. He said families living in high-risk areas will be forced to move if necessary, conceding that some of the city’s past efforts to relocate occupants of squatters’ villages have been met with resistance.

In Northern California, seven inches of rain fell near the Sonoma County town of Healdsburg between 2 p.m. Tuesday and 2 p.m. Wednesday, and forecasters said the rain should keep coming down until tonight. Officials said the Russian River could flood the wine country town of Guerneville before dawn today if the downpour continues.

The Sonoma County Office of Emergency Services declared a state of emergency and evacuated residents of a trailer park in Guerneville as the river began spilling over its banks late Wednesday, leaving several homes awash.

About 15 miles to the south, in Petaluma, about 250 residents of 100 houses along the Petaluma River were evacuated late Wednesday as the river began to overflow.

“It is over its banks, in the back yards of these homes, through the side yards and running into the street,� said Bonnie Bard, a spokeswoman for the city of Petaluma.

In Napa County, water from the Napa River and a tributary creek spilled into the streets of Napa, forcing the evacuation of several blocks of houses and a nearby mobile home park.

In Trinity County, the rising waters of the Mad River cut off about 350 residents in the tiny hamlets of Ruth and Trinity Pines.

In Marin County, Kent Middle School and Bacich Elementary School were closed as a precaution as the waters rose in Corte Madera Creek. Catherine Branson School, a private school in neighboring Ross, also was closed.

Scores of roads in the northern half of the state were blocked by mudslides and rising floodwaters. An avalanche dropped 15 feet of snow onto U.S. 50 near Lake Tahoe, and officials said the road probably would not be reopened until late today.

The stormy weather reached no farther south than the middle of the state on Wednesday, and in Southern California, it was time to assess the damage, shovel out mud and offer thanks for forecasts that promise dry weather through the weekend.

In Ventura County, farmers said floodwaters earlier in the week had severely damaged broccoli, celery, lettuce and strawberry crops, which probably will soon mean higher prices at grocery stores.

Officials said at least 600 people were still isolated by storm-damaged roads in the remote De Luz Hills of Riverside and San Diego counties on Wednesday.

Along the coast, at Camp Pendleton, Marines returning from Somalia found the drenched base closed to all but residents and essential personnel.

No dollar estimate of flood damage at the base had been made, but with two bridges washed out and widespread additional damage, the figure is expected to reach into the millions.

Also damaged at the sprawling base was a chapel dating from 1810 that was virtually demolished by a torrent of mud and water.

“It looks like a tank drove in one side and out the other,� said Master Gunnery Sgt. John Farrell, a base spokesman.

Farrell said preliminary checks have shown that none of 70 flooded helicopters had sustained major damage. However, he said, some of the helicopters had yet to be checked because the gear needed to assess the destruction was missing.

“It just floated away,� he said.

Malnic reported from Los Angeles, Kraul from Tijuana.

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