A highway blocked by a landslide had been cleared of a soupy mixture of gravel, mud and trees Wednesday but it remained closed because water was still rushing across the pavement.

Nobody was injured by Tuesday's slide, which destroyed two houses, struck others and covered an area estimated to be three football fields long.

State highway crews had worked all night with heavy equipment to clear U.S. 30, but found there was still enough water flowing across it to be a hazard to traffic and the roadbed.

There was no estimate of how soon the road might reopen, said Christine Miles, spokeswoman for the Oregon Department of Transportation.

Engineers were trying to figure out how to stem or divert the water.

U.S. 30 runs along the Columbia River, linking Portland and the Pacific Coast.

More than 10 inches of rain had fallen on parts of the region during two recent damaging storms.

"When you get that much water in that soil, it's basically a lubricant," said Rod Nichols, a spokesman for the Oregon Department of Forestry.

Debris high above the highway had plugged a culvert through an abandoned railroad grade, backing up water into a pond 40 feet deep, Nichols said.

The company that owns the land notified the state days ago of the slide potential. People living below the pond were evacuated Monday, and on Tuesday warnings that a slide was imminent led the highway department to close the road about an hour before the mud and debris started moving.