FRISCO — Officials are hoping to make improvements to the Exit 203 interchange in Frisco to help alleviate some of the current traffic congestion in the area and to help prepare the town for increased traffic in the future.
Representatives with the Colorado Department of Transportation provided an update to the Exit 203 interchange project during a virtual meeting with the Frisco Town Council and county officials last week, highlighting ongoing problems in the area and possible solutions.
The feasibility study was funded via matching contributions from Frisco and Summit County, and dove into roadway issues like safety and lane balance from Exit 205 in Silverthorne to Exit 203 in Frisco — along with other trouble areas leading up to the interchange, like the Lusher Court and Dillon Dam Road intersection with Colorado Highway 9.
In regard to existing conditions, officials pegged traffic coming into Frisco on the westbound Exit 203 off-ramp as a major concern, noting that the level of service on the single-lane roundabout is operating at an “E” on an A-to-F scale and that traffic often backs up onto Interstate 70.
“In the existing conditions, the queue lanes backing up onto I-70 are causing a lot of problems today,” said Corey Lang, a consultant with WSP, a firm that helped produce the feasibility study. “Even though there is an auxiliary lane that drops into the off-ramp, that backup is starting to get all the way back to the scenic overlook. And you get big differentials in speed, which is a dangerous situation.”
The other intersections in the area — including other on- and off-ramps at Exit 203, and the Lusher and Dillon Dam intersections with Highway 9 — aren’t suffering from the same backlogs quite yet.
Though, in forecasting traffic conditions out to 2045 — which include assumed developments like the Lake Hill housing project — officials believe that all of the intersections in the area soon will be deficient, with Lusher and Dillon Dam traffic backing up and severely impacting off-ramps and creating longer queues.
“As we project those traffic volumes out and look at future conditions, all the intersections fail,” Lang said.
The group has come up with a revised concept to try to combat the issue. The idea is to expand the Exit 203 roundabout to two lanes and create a new frontage road underpass to the north of Lusher Court. The bypass would loop around and connect with Lusher Court via a new roundabout and continue east under Highway 9 into another roundabout and onto Dillon Dam Road.
As a result, southbound traffic coming off I-70 no longer would be able to turn onto Dillon Dam Road, and would instead turn right onto Lusher Court and into the roundabout. It also would move the traffic signal from the Lusher-Dillon Dam intersection to north of the eastbound on-ramp.
“We’re designing for that Saturday afternoon peak period where we get really heavy traffic,” Lang said. “But what this also does is eliminates the need in the off peak periods for vehicles to have to sit through signals. … By making these all right turn only and roundabouts, you reduce a lot of that delay.”
Lang said the design is conceptual and that there would be opportunities to continue to optimize the plan to minimize potential impacts to things like parking. He noted one of the benefits of the design is that it could be implemented in phases, with the two-lane off-ramp coming sooner to address existing backups and adding the frontage road bypass as traffic grows.
Lang also discussed plans for an eastbound auxiliary lane on I-70 from Frisco to Exit 205 in Silverthorne. He said that adding the additional lane would create considerable improvements to the level of service and safety on the roadway.
The town council discussed the plans relatively sparingly but asked Lang and CDOT to consider other opportunities during construction, like the creation of wildlife safe passages on I-70, and to take potential impacts from new and growing technologies like autonomous and electric vehicles into their plans.
Otherwise, feedback was positive.
“The evolution of the plans seem to have gotten us to a much better place than where you all started,” council member Andrew Aerenson said. “But the part that wasn’t mentioned that’s also another benefit is the connectivity of east and west Frisco. … That looks like a great solution to a real problem at the moment.”
Officials are hoping to finish final designs sometime next year and start construction in 2022.
But funding remains a question mark.
“The situation with the funding right now is we don’t have the $20 million that we thought we did,” said Grant Anderson, CDOT’s resident engineer for the region. “It’s coming from bonds … but they’re not probably going to go forward. But we are going to continue design of that project to have it shovel ready in the event that funding situation changes.”
Officials are planning to host a virtual open house later this month for members of the public to learn more about the project.