The Alaska Department of Transportation says highway access to Valdez has been cut off indefinitely by avalanches, including one that dammed a river and created a lake up to a half-mile long across the roadway.
Officials say the snow slide about 12 miles outside Valdez on the Richardson Highway can't be cleared until water behind the snow drains. The water in Keystone Canyon is too deep on the upstream side for crews to approach the snow dam. Officials fear that digging from the downstream side could trigger a dangerous surge of water and harm work crews.
DOT maintenance engineer Mike Coffey estimates snow is piled 100 feet high on the Lowe River and up to 50 feet high on the highway.
A second avalanche is blocking the highway at Mile 39.