Hugh Carey / hcarey@summitdaily.com
Residents and frequent visitors through the Interstate-70 corridor will likely be familiar with Exit 203.
The interchange serves as something of a gateway to the West, a main ingress and egress for mountain visitors seeking further passage to Breckenridge or a centralized hub for shopping, dining and recreating in Frisco.
But during certain times of the year, when the weather is right and visitors are abundant, the growing issues surrounding the interchange and segments of I-70 become highly visible. Motorists will see a line of cars heading west queued up in front of the roundabout, and the frustrated faces of even more drivers slowly plodding toward the on-ramp to Silverthorne.
As problems with safety and capacity continue to grow on the roadways in the area, the Colorado Department of Transportation is pushing forward with efforts to address the issues, though solutions may be years away.
“CDOT really is interested in making a difference in this corridor,” said Stephen Pouliot, Colorado civil team leader with WSP, a consulting firm working with CDOT. “We understand there are lots of issues with safety problems happening on the eastbound downhill portion of I-70, and a real safety problem at the interchange. They don’t want to have that big accident happen before they do something, so they’re trying to be as proactive as possible. … Safety and operations are very tied together, and as the population and congestion grows those things tend to get worse. It’s not just going to get better.”
CDOT, along with a number of project partners, has launched a new feasibility study focused on improvements for three main projects in the area: the I-70 and CO 9 interchange at Exit 203, the intersection of CO 9 and Dillon Dam Road, and eastbound lanes on I-70 from Frisco to Silverthorne. At an open house in Frisco on Wednesday, representatives with CDOT met with members of the public to discuss the issues and potential improvements.
The areas of focus were identified by CDOT as far back as 2011 in the department’s I-70 Mountain Corridor Programmatic Environmental Impact Statement, which called for modifications to the “structurally deficient” interchange, and an auxiliary lane along eastbound I-70 from Frisco to Silverthorne.
Among CDOT’s biggest concerns is congestion in the area. The group, using data from last year, identified some of the most troublesome areas. Some of the worst offenders included both the eastbound on-ramp (988 cars per hour during peak traffic volume) and off-ramp (836) at the interchange, along with both the westbound on-ramp (854) and off-ramp (854), which see considerably higher traffic volumes than other sites. The intersection at Highway 9 and Dillon Dam Road also presents difficulties, especially for through traffic heading toward the interchange (931) and onto CO 9 from I-70 (808).
“We’ve got a bunch of ideas in the back of our heads, but how do you get 20 gallons of water through a 10 gallon pipe?” said David Sprague, lead traffic consultant with Atkins. “There’s a lot of traffic in a very small, compact area. We’ll be limited in our options, but we’re looking at everything we can.”
Safety issues are the other major concern as CDOT seeks improvements to the area. A recent safety assessment outlined some trouble areas where crashes are most common, primarily between mileposts 204 and 205 just before Silverthorne. The group also noted that the difference in speeds between westbound I-70 and the off-ramp onto Exit 203 creates unsafe conditions.
“We see safety problems almost weekly now westbound at the 203 off-ramp,” said Grant Anderson of CDOT. “Our safety report that we did to kick this study off looks at all of the accident data in this segment. It showed that the Silverthorne hill eastbound is actually above state average in terms of accident frequency.”
With the problems well defined, the next steps for CDOT will be coming up with potential alternatives to improve safety and congestion on the roadways. While the study is still in its relative infancy, CDOT has already floated a few potential fixes including conceptual designs for a new eastbound auxiliary lane from Frisco to Silverthorne, a two-lane roundabout at the interchange, and the installation of traffic signals in lieu of a roundabout at the interchange.
Ultimately, the decision on what solutions make the most sense will come down to a combination of public input, working with Frisco and the county to forecast future travel demands, conducting field studies of potential environmental concerns and looking at major projects in the future like the Lake Hill housing development to determine the potential effects of those changes.
And while CDOT hopes to have alternatives designed by this summer, a lack of funding could potentially push back any meaningful construction work for years.
“We do have funding that we’ve attracted to take some of these concepts further, and then we’re going to have to stop,” said Anderson. “We don’t have the construction funding identified. That’s critical to understand right now. But the more we can set the table by having something ready, the more it’ll attract funding in the future.”
Individuals hoping to voice their opinions on potential alternatives should reach out to the project team via Tracy Trulove at Tracy.Trulove@state.co.us.