EVERGREEN – Highway crews detonated 4,400 pounds of explosives packed into 150 holes drilled into Clear Creek Canyon west of Denver on Tuesday, blowing up clouds of dirt and loosening 5,000 cubic yards of rock above Interstate 70 as they ramped up work on Colorado’s $800 million project to straighten some of  I-70’s tightest and most treacherous curves. Colorado Department of Transportation coordinators working with local police stopped traffic. Suddenly creek water ripples became audible before air horn blasts signaled the start of a countdown. “Fire in the hole!” “This is to make room for I-70,” CDOT project director Kurt Kionka said. “It will remove that bottleneck. Traffic will flow much better.” The detonation was the 30th since October forcing traffic stops for up to 20 minutes and overall travel delays up to 45 minutes for I-70 drivers between Evergreen and Idaho Springs. Drivers will face at least 200 more stops and delays as CDOT’s contractor Kraemer North America sets off explosions between this week and the end of 2026. The schedule allows blasting about three times a week on Monday through Thursday between 9 a.m. and 3 p.m. and on Fridays between 9 a.m. and noon. Kraemer crews plan to complete much of the heaviest blasting over the next few months. Bulldozers can sweep newly loosened rock down from a canyon feature engineers call “the saddle cut” into giant yellow dump trucks for hauling to fill sites for other parts of the I-70 overhaul. A rebuilt highway, with a third westbound express toll lane, will carry drivers through the canyon on viaducts 115 feet above Clear Creek — a safer route with increased visibility, allowing speeds of 55 miles per hour in areas now marked 45 mph. Kionka’s advice to drivers caught in the holds? “Stay the course,” he said, rather than trying to escape I-70 along frontage roads. Traffic “backs up a bit. But it also clears out quickly.”  More than 13,000 Colorado drivers have signed up for a CDOT trip-planning service (text to 2100floydhill) to receive alerts when blasting is scheduled. Before and after rock blasting, CDOT crews climb over the canyonsides, using ropes, and conduct rock hazard “mitigation” work – clearing remaining loose rocks. That’s a focus for CDOT, agency spokeswoman Stacia Sellers said. “Mitigation is necessary to eliminate the potential of a natural rock fall hazard for motorists.” The federal government has committed $100 million to help cover the costs of CDOT’s I-70 Floyd Hill Project, scheduled for completion in 2028. The project includes work to improve creek flows and a riparian corridor, where a recreational greenway trail will carry hikers and bicyclists. CDOT also plans improvements to help fish and wildlife withstand the impact of increasing I-70 traffic.