Floodwaters damaged a 66-mile stretch of highway so severely that the road could be closed as long as a week, blocking Valdez from the rest of Alaska, state officials said Wednesday.

"There are huge washouts in the roadway and approaches to bridges," said Shannon McCarthy, a spokeswoman for the Alaska Department of Transportation. "We have debris on the road. We have mudslides. We have asphalt that's literally missing, that just washed away."

The heavy rain that poured over Valdez and other southern Alaska communities this week had eased to lighter showers by Wednesday, National Weather Service forecasters said. Conditions were expected to improve by the weekend in southern and eastern parts of the state.

The break in the weather gave affected residents a chance to assess the damage or return to homes following evacuations Tuesday in some communities, including Valdez, 97 miles east of Anchorage and the terminus of the 800-mile trans-Alaska oil pipeline. No injuries were reported.

At least one home, a trailer, disappeared under a mudslide when no one was home, said Lee Revis, a Valdez newspaper editor who was among 100 people who fled their homes when a river breached a nearby levee and flooded the area.

Floodwaters from various rivers left mangled piles of mud, rock and tree branches along the Richardson Highway, damaged bridges and crumbled pavement. In one section, debris was six feet high over a 200-foot stretch, McCarthy said.

The road is the only way out of Valdez by vehicle. Until it's passable again, the only other ways in or out of town are by plane, boat or state ferry. With much of the incoming freight carried by vehicles, local merchants such as the two grocery stores were ordering supplies to be ferried in, said city spokeswoman Sheri Pierce.

Meanwhile, residents were stocking up on supplies.

"The bread shelf was very bare when I went," Pierce said. "Everything else looked OK."