Western Washington Rivers Flood as Rain Melts Snowpack : Storm: Several hundred families are evacuated to high ground in coastal valleys. Scores of highways are also closed by rising water and mudslides.

Fed by warm rain and melting snow, rivers all across western Washington state surged over their banks Saturday, forcing several hundred families to flee to high ground and putting countless others on alert for major flooding.

At least 10 significant rivers exceeded flood stage by Saturday afternoon, and the National Weather Service reported that some rivers would rise to twice the flood level as the steady downpour stripped the snowpack off the Cascade Mountains.

Flooding was reported in coastal valleys from the Canadian border to south of Olympia. Every county west of the Cascade divide reported flood problems, although evacuations were required primarily from flood-plain farms and low-lying areas of scattered rural communities.

Among the evacuees was one group of 50 people who had been cutting Christmas trees in the National Forest not far from Mt. Ranier. Another 150 people were forced from their homes in King County. Other small groups were sure to push the number of evacuees higher, although state officials said an accurate count was impossible.

Gov. Booth Gardner activated one unit of the Washington National Guard to assist in evacuations and sandbagging in the much-suffering flood plain north of Everett. Other units were placed on standby.

Behind the flooding was a wet and powerful storm that had unexpectedly stalled over the Cascades, dropping as much as five inches of rain since Friday. Rain continued into the evening Saturday, but weather service officials said drier, cooler weather was on its way.

The small community of Sultan north of Seattle was reported flooded under as much as four feet of water. Just east of Seattle, rising waters drove police out of their headquarters in the community of Snoqualmie, the setting used in the filming of TV’s “Twin Peaks.”

A $2.5-million home east of Seattle was pushed off its foundation and onto the beach of Lake Washington by a mudslide.

Officials said that a flood of this extent would take a toll of both livestock and wildlife.

Scores of highways and mountain passes were closed by rising water and mudslides during this heavily traveled holiday weekend. Scattered urban flooding also occurred in the region, including in Tacoma, Gig Harbor, Renton and Puyallup.

Travelers everywhere faced standing water on roads and freeways. Track washouts and mudslides shut down the Burlington-Northern rail line, a busy east-west link across the northern United States, stranding two freight trains. The line was not expected to be reopened for at least 72 hours.

This was the second bout of flooding to wash across western Washington in two weeks. In some areas, officials and longtime residents said it was the worst seen in at least 15 years. That is no small statement, considering that the valleys at the base of the Cascades endure wild river rises almost every autumn as arctic storms and snowfall are routinely followed by heavy tropical-fed storms.

Another measure of the extent of the emergency: The state of Washington ran out of sandbags at midday Saturday, having dispensed 100,000 in the last two weeks and 35,000 in the last 12 hours.

Fir Island, an agricultural tract in the delta area of the Skagit River that was hard hit in the flooding two weeks ago, had just begun to dry out when the river rose to even higher levels Saturday. About 500 people were evacuated in the first flooding, and officials said that more might be forced onto high ground this time.

Among other rivers exceeding flood stage were the Nooksack, Stillaguamish, Skynomish, Snohomish, Snoqualmie, Cedar, White and Puyallup.

Times researcher Doug Conner assisted with this story.