"CDOT officials are extremely pleased with the outcome," the agency said in a video showing the blast.
CDOT said that trucks immediately started hauling the fragments away so crews can begin constructing a temporary roadway in order to reopen the highway for traffic.
A photo posted by the agency showed pieces of the rubble as workers surveyed the scene.
The massive rock tumbled down as part of a "significant" rock fall Friday afternoon along Colorado Highway 145 about 12 miles north of Dolores, located in the southwest part of the state.
A photo posted by the city of Ouray showed a person standing in front of one of the boulders, which officials said is the size of a building.
Another large boulder carved an 8-foot trench as it went over the roadway, and is estimated to weigh 8.5 million pounds.
That second boulder landed on the east side of the road and may remain where it sits, according to CDOT.
It’s relatively common for boulders and smaller rocks to fall on mountain highways, particularly in spring after the repeated melting and freezing of snow and ice creates new fissures on the mountainside.
But Friday’s rock slide along state Highway 145 between Cortez and Telluride was unusual in that it began on a slope about 1,000 feet above the highway, according to FOX31.