Updated

Hundreds of homes sat in as much as 8 feet of water Sunday following a canal rupture as freezing weather spread sheets of ice over yards and streets, hindering efforts to get the water to drain away.

Nearly 300 homes were damaged when the canal's bank gave way following heavy rainfall produced by the West Coast storm system that had piled snow as much as 11 feet deep in the Sierra Nevada.

Thousands of customers were blacked out across the West and many of them in California could remain in the dark for days because the storm ripped down nearly 500 miles of power lines, utility officials said Sunday.

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More than 145,000 homes and businesses in Northern California and the Central Valley were still without power Sunday, down from more than 215,000 earlier in the day, ahead of rain and snow that were forecast to return again soon.

Six snowmobilers and two skiers were reported missing in heavy snow in the mountains of southern Colorado, and one hiker was missing in snow-covered mountains in Southern California.

At least three deaths were blamed on the storm.

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The irrigation canal failure at Fernley released a wave of frigid water into the town early Saturday.

"In 10 minutes the entire back yard was completely flooded. It was just nothing but water," said Kristin Watson, whose home backs up to part of the canal. "We just sort of panicked because we knew we had to get out of there real quick."

The canal was temporarily repaired by late in the day, but as much as a square mile of the town was still under water at least 2 feet deep Sunday as ice impeded drainage.

"Our hope is over the next 24 hours to get the water out," Fernley Mayor Todd Cutler said at a briefing Sunday morning. "But we still have up to 8 feet of water in some areas. We need to keep the storm drains unclogged to keep the water moving to a wetland. We also may need to do some pumping in some areas."

Lyon County Fire Division Chief Scott Huntley estimated 1,500 people had been displaced. No injuries were reported in the town of 20,000 people about 30 miles east of Reno.

Huntley said officials knew of 18 cases of people rescued from atop homes or cars as fire department and private boats plus four helicopters were pressed into action Saturday, but he believes there were many more.

"The sheer number of rescues was amazing," Huntley said Sunday.

"For citizens to give of themselves and to help their neighbors, I'm choked up about it," Cutler said.

An initial assessment Sunday found 290 homes received varying amounts of flood damage, said Kim Toulouse, spokesman for the Nevada Division of Emergency Management.

Despite heavy rain Friday, Gov. Jim Gibbons said the canal was not full when the bank failed. "This indicates to me there might have been a structural weakness over the years. Nobody knows and we don't want to speculate at this time," he said.

One possible factor that officials have mentioned was rodents burrowing holes in the earthen bank, which also was involved in a smaller collapse that flooded about 60 Fernley homes in December 1996.

But Ernie Schank, president of the Truckee-Carson Irrigation District, said Sunday that a geologist had turned up no evidence of burrowing animals near the site of the break. The cause may never be known, he said.

"It'll be hard to pinpoint the cause because the evidence is washed away," said Schank, whose agency operates the 31-mile-long earthen canal.

Rescuers in Colorado searched for six snowmobilers last seen Friday, before the storm dumped 3 to 4 feet of snow near Cumbres Pass, close to the New Mexico line.

The snowmobilers were two couples from Farmington, N.M., and their two children, ages 14 and 13, said Betty Groen, the stepmother of one of the missing men.

Donna Oney of the Colorado State Patrol said search and rescue team members were looking for the snowmobilers. The search was halted as night fell, to be resumed Monday.

Two skiers were missing 40 miles away in the Wolf Creek ski area, Oney said. Wolf Creek had reported 39 inches of snow overnight

In the mountains east of Los Angeles, authorities searched Sunday for a 62-year-old man who went hiking Friday just before the storm began, San Bernardino County sheriff's spokeswoman Arden Wiltshire said. Searchers last had cell phone contact with him early Saturday, before snow began falling in the area.

In the rugged Sierra Nevada range, the Kirkwood ski resort near Lake Tahoe reported about 11 feet of snow had fallen since the storm system moved inland from the Pacific last week.

As much as 3 feet more snow could hit higher elevations of the Sierras by Tuesday evening, the National Weather Service said. Parts of Northern California will get a reprieve from the rain and snow on Monday, but in the mountains, "there's a chance of snow and snow showers all the way through Thursday," said weather service meteorologist Angus Barkhuff.

More than 215,000 homes and businesses in Northern California were still without power Sunday, and Pacific Gas and Electric said the storm had downed nearly 500 miles of power lines and more than 500 utility poles. Repair crews in the snow-covered Sierra foothills will have to use snowshoes, all-terrain vehicles and helicopters, utility officials said.

The storm also caused blackouts in parts of Oregon, Washington and Colorado.

In all, more than 2 million customers from the northern town of Eureka to Los Angeles had lost power since early Friday.

Seven people were hospitalized at Willows, Calif., near Chico, after suffering carbon monoxide poisoning from a propane lantern they used indoors because of the blackout, Glenn County officials said.

The storm was blamed for two deaths in California, including a woman whose pickup truck was swept into a flood channel east of Los Angeles, and one death in Oregon, police said.

In Wisconsin, more than 100 cars were involved Sunday in a series of pileups that killed two people on a foggy five-mile stretch of highway just southeast of Madison.

Flares lining Interstate 90's lanes were brought in to cut through the fog as traffic crawled and visibility was down to about 100 yards.