JEFFERSON COUNTY, Colorado —

The Colorado Department of Transportation said crews likely will not be able to open eastbound US 36 at Wadsworth Boulevard by the start of the work week as repairs continue on a portion of the road where a large crack appeared overnight Friday. 

"We are looking at a pretty large slope failure on US 36," CDOT Chief Engineer Joshua Laipply said during a news conference on Saturday afternoon. 

The crack impacts a 200-foot stretch of the road. In a news release, CDOT said it was likely caused by moist soil under the highway. Crews later found a "void" in the road base between 150 and 200 feet long and 10 feet wide. 

Laipply said CDOT knows how to repair a slope failure, and efforts are now underway to determine the cause. The agency is looking for a contractor to complete repairs and hopes to have one in place by Sunday. 

While the work is underway, Laipply told drivers to avoid the highway. 

"I would advise not taking US 36," he said, adding that drivers headed between Denver and Boulder should either opt for CO 7 to Interstate 25 or CO 93 to CO 58, which connects to I-70. 

There's no timeline for when the repairs will be complete. 

The US 36 bike path is expected to close on Saturday night in the area of the crack. CDOT said it could remain closed through Sunday and possibly longer with a detour in place. 

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