The Colorado Department of Transportation will begin work at one of Summit County’s busiest interchanges, Interstate 70 Exit 203, in Frisco on Monday, April 20. 

Contractor Zak Dirt and CDOT crews will work day and night shifts Monday through Saturday with occasional Sundays as needed, according to a news release sent by Austyn Dineen, Interstate 70 mountain corridor communications manager. Day shifts will be from 7 a.m. to 7 p.m. while night shifts will be 7 p.m. to 7 a.m.

The project aims to reduce traffic congestion, enhance safety features and add bicycle and pedestrian connections along Colorado Highway 9, Lusher Court and Dillon Dam Road at the north end of Frisco — an area that has long experienced heavy backups during peak travel times. 

In early May, CDOT has planned a short-term daytime detour on Dillon Dam Road to accommodate a sewer installation. Otherwise, CDOT plans to only close lanes on Highway 9 and Interstate 70 during nighttime hours — between 7 p.m. and 7 a.m. — to minimize impacts to daytime traffic. During the night shift, crews will place lane barriers and begin re-striping. 

No full road closures are anticipated during the first stage of construction, which is scheduled to end before November of this year. The second stage will likely commence in April 2027 following a winter shutdown. While CDOT has said impacts will be felt during both construction seasons, officials have indicated that 2027 will likely bring the most disruption as major roadway features are completed. 

Construction will occur in multiple phases, with work this year focusing on foundational elements, including work on the Interstate 70 bridge structure, retaining walls and part or all of a new Highway 9 underpass. Next year, crews are expected to complete the bridge and construct a new frontage road bypass under Highway 9 to link Dillon Dam Road and Lusher Court to further relieve traffic at the interchange just slightly to the north. 

The first phase of work also entails a short-term reconfiguration of traffic lanes along Highway 9 and the Interstate 70 exit ramps to allow roadwork to proceed safely. Additionally, CDOT plans to widen the Interstate 70 overpass and add a 10-foot-wide multi-use path to more safely accommodate cyclists and pedestrians traveling over the interstate. 

While exiting onto the I-70 westbound offramp for Exit 203 will remain a single lane, widening the offramp to two lanes should better hold traffic, according to Scott Harris, project manager with CDOT. Eventually, a traffic signal will be added to the I-70 westbound Exit 203 offramp in lieu of a roundabout. 

CDOT Executive Director Shoshana Lew wrote in a news release that the project to redesign the Interstate 70 mountain corridor, starting with Exit 203, has been in development for nearly five years.

“Breaking ground on the Exit 203 project marks a major milestone for the Interstate 70 mountain corridor, the primary thoroughfare to our popular mountain communities,” Lew wrote. “By enhancing multimodal access through regional services like Bustang and county-wide offerings like the Summit Stage, we are ensuring a safer, more efficient interchange for our local residents and the millions of visitors who travel through this gateway.” 

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The Exit 203 interchange has long been identified as a chokepoint in Summit County’s transportation network, particularly during peak travel seasons when a larger volume of interstate traffic converges with local travel along Highway 9. The heavy traffic and congestion — driven both by daily commuters and vacationers heading to ski resort and recreation areas — frequently lead to back-ups on exit ramps and create safety concerns for drivers, cyclists and pedestrians. 

Transportation officials say the redesign will separate local and through traffic, reduce stop-and-go conditions and modernize infrastructure that has struggled to keep pace with growing demand. 

Construction will also address aging stormwater and utility infrastructure between Highway 9 and Dillon Dam Road. According to CDOT officials, the combination of traffic capacity improvements, expanded travel options and safety upgrades will better accommodate growth in both local populations and visitor numbers while reducing congestion at one of the county’s busiest gateways. 

Residents interested in learning more about CDOT’s planned construction near Frisco can access a project resource page at CODOT.gov/projects/i70-exit203-interchange-frisco, or sign up for project updates at Subscription.COtrip.org.