Interstate 70 will remain closed in Glenwood Canyon through the entire weekend, the Colorado Department of Transportation said Saturday, as efforts to clear heavy debris and mudslides continued.

Crews worked “aggressively” to clear the interstate on Saturday, hauling 135 truck loads of mud and rocks away from the area. Despite the progress they made, however, the department said there would be continued risks for crews, who will only “work aggressively” when it is safe to do so.

Specifically, transportation officials pointed to continuing flood concerns in Glenwood Canyon, for which a flash flood watch was placed in the area through midnight on Saturday by the National Weather Service.

Those continuing concerns were in part caused by lingering monsoonal moisture in west and central Colorado, the department said.

On Thursday night, mudslides and debris spilled onto I-70 in around ten different locations, trapping 29 within the Hanging Lake tunnel complex and forcing 108 in total to spend the night in the canyon.

Those 108 were eventually rescued or evacuated from the safe locations they’d previously been moved to on Friday, which the department said at the time was the main focus of its efforts.

More than 20 rescued from tunnel on Colorado’s I-70 after storm in Glenwood Canyon

Transportation officials strongly asked that drivers in the area continue to use their recommended alternate route through Colorado 9, U.S. 40, and Colorado 13, instead of navigation apps.

They also advised drivers to plan ahead for their trips by checking weather conditions and COtrip.org, giving themselves extra time to travel in weather, and prepping their cars with emergency kits and adequate tires for intense weather.