Construction is set to begin later this month on a five-year, $700-million safety and capacity improvement project along an eight-mile segment of Colorado’s notoriously congested I-70 Mountain Corridor.
Kraemer North America is construction manager for the Colorado Dept. of Transportation project located west of Denver between Evergreen and Idaho Springs. A key element of the project will be the addition of a westbound tolled express lane at Floyd Hill, where increasingly frequent congestion can be exacerbated by severe winter weather conditions.
“The I-70 Mountain Corridor, particularly at Floyd Hill, is the gateway to Colorado’s mountains and a critical economic and tourism route,” said CDOT I-70 Floyd Hill Project Director Kurt Kionka in an agency statement. “By eliminating the bottleneck at Floyd Hill, the project will significantly ease congestion and decrease the number and severity of crashes.”
Other work includes reconstruction of several aging bridges and other structures, filling a two-mile gap in the existing frontage road to improve emergency response, curve safety modifications that improve travel speeds and sight distance, installation of two permanent air quality monitors and extending an existing entrance ramp from U.S. Route 6 near Idaho Springs to accommodate safer merging by large trucks and other slow-moving vehicles.
Atkins North America, Inc., led the design of the I-70 Floyd Hill improvements under a six-year, $31-million CDOT contract.
Plans calls for construction to be carried out in three phases, beginning with the easternmost four-mile section between County Road 65 to the bottom of Floyd Hill. I-70’s existing travel lanes will be maintained in each direction during peak travel hours.
Funded by a combination of state and federal sources, including a $100-million grant from the Nationally Significant Multimodal Freight and Highway Projects program, the I-70 Floyd Hill project is the first significant upgrade to the Floyd Hill section since it was opened in the early 1960s, according to CDOT. It’s also the state’s largest transportation project since the $1.2-billion expansion of I-70 through Denver, which is nearing completion.
CDOT has already launched several community and environmental mitigation projects identified during the Floyd Hill Environmental Assessment process. Last year, American Civil Constructors began work on a $9-million project to add new roundabout intersections adjacent to two I-70 interchanges. A $10-million project underway by Lawrence Construction will construct a wildlife underpass near mile point 254.5, a location that CDOT says has the highest number of wildlife-vehicle collisions on I-70 east of the Eisenhower Johnson Memorial Tunnel. The project also includes approximately two miles of wildlife fencing on both sides of I-70.
Later this year, CDOT plans to begin construction of a wildlife overpass along U.S. Route 40 near I-70’s Empire interchange to provide safe connectivity for Colorado’s largest herd of bighorn sheep. This project also plans to apply rockfall mitigation designs and fencing adjacent to the wildlife crossing structure. CDOT has not selected a contractor for the project, which the agency currently estimates will cost between $7 million and $10 million.
