Several major highways, including Interstate 70, have been closed in recent weeks because of the mudslides. Some highways were covered with boulders, trees and mud as much as 25 feet deep.
Officials are worried that avalanches may follow the same routes as the mudslides, and are working on ways to prevent that.
The worst repair costs are a 2 ½-mile section of I-70 between Bakerville and Loveland Pass, and on the pass itself. A massive slide here closed the interstate for more than a day.
Highway department officials say they will request more than $1.6 million from the federal government, and may need more funds later.