The most recent iteration of the entrance to Aspen includes changes to the Maroon Creek roundabout and Cemetery Lane access, updates that were made after months of reevaluation work and community input on the project.
The city of Aspen embarked on a reevaluation of the 1998 “preferred alternative” design for the entrance under direction from Aspen City Council last summer. The city has worked with consultant Jacobs Engineering, the Federal Highway Administration, the Colorado Department of Transportation and other community stakeholders to reevaluate the plan, measuring whether some modern modifications to the proposed highway alignment would pass muster against state and federal regulations for a reevaluation of such a project.
The project team evaluated a number of refinements to the design, many of which were eliminated after several levels of screening. Those that remained include a lane connecting Cemetery Lane to the new Highway 82 alignment (the original preferred alternative cut that access) and new slip lanes in the Maroon Creek Roundabout to ease traffic.
The refinements are meant to “optimize the [preferred alternative],” Jim Clarke, a senior project manager with Jacobs Engineering, told the city council on Tuesday.
“There’s relatively minor modifications to better meet the project purposes and the project objectives,” he said.
The community got its first look at the proposed refinements in March, when it hosted an open house to gather public feedback on the design. Some proposals that didn’t make it past the several levels of screening included back-to-back roundabouts near the Aspen Airport Business Center and toll lanes.
While the modifications were evaluated based on the state and federal requirements for a reevaluation, Clarke said the public input did play an important factor in the project design. An overwhelming amount of public feedback showed the community wanted to restore direct access to Highway 82 from Cemetery Lane and did not want to see new traffic signals on the way into town.
The designs presented to council members on Tuesday are still conceptual and subject to revisions, said Doug Stremel, a senior roadway project manager with Jacobs Engineering.
The updates to the Maroon Creek roundabout — including slip lanes from Highway 82 to Maroon Creek Road, a slip lane between Maroon Creek and Castle Creek roads and an additional bus-only lane through the roundabout in the downvalley direction — were efforts to ease congestion in the roundabout.
“[They are] just separating some traffic from the roundabout and easing that congestion,” Stremel said.
Connecting Cemetery Lane to the new Highway 82 alignment would allow people who live in the area to still use Cemetery Lane to go downvalley on Highway 82, instead of having to drive into town over the existing Castle Creek Bridge (which would become a local road under the new entrance) and go to 7th Street to connect with the highway. Left turns would be prohibited off Power Plant Road in an attempt to mitigate the “West End sneak” out of town.
The newest proposal also realigns Owl Creek Road to meet Harmony Road where it intersects with Highway 82, eliminating the existing traffic signal at Buttermilk. The Roaring Fork Transportation Authority bus stops at those intersections would remain in the same place. Stremel said the new Owl Creek realignment was cleared with the Aspen-Pitkin County Airport.
The designs show new traffic lights at 7th and Main streets and 4th and Main streets for increased pedestrian safety.
The original preferred alternative included a 400-foot cut-and-cover tunnel over the roadway as it crosses over the Marolt and Thomas open spaces. It was part of the requirement of the original 1998 decision, to mitigate for impacted open spaces.
The tunnel is not off the table in the newest designs, but it will require additional modifications as the reevaluation process continues, Stremel said. Because CDOT will own and maintain the tunnel, and because state regulations on fire safety for tunnels have become more stringent since the 1990s, the state agency asked the project team to explore a smaller tunnel, potentially 300 feet, Stremel said.
It will require “much larger engineering analysis,” he added.
Other improvements would include a new Nordic trail bridge over the Cemetery Lane connection, a new access road to the Holden Marolt Mining and Ranching Museum and a new pedestrian underpass connecting to Cemetery Lane.
The project team conducted a traffic analysis to estimate traffic growth in the valley by 2050. The analysis, which took into account valley developments, found there would be about 240 additional vehicles coming into and out of Aspen during peak times by 2050.
Under the traffic model, it showed the refined preferred alternative would cause “medium” delays, with a medium-to-high rate of person throughput, largely due to the elimination of the S-curves and modifications meant to ease congestion.
The refined preferred alternative with permitted HOV lanes would cause the lowest delays and highest throughput, but the Roaring Fork Transportation Authority told the project team that it opposed the use of its dedicated bus lanes for HOV traffic. And, City Attorney Kate Johnson previously told the city council that the city would have to go to voters if it wanted to allow general traffic to use the bus-only lane into Aspen, because it would be in violation of an easement the city council conveyed to CDOT in 2002.
If a vanpool service was implemented to use the bus lanes during peak hour traffic, there would be no adverse impacts to the bus service, Stremel said, but, “there would have to be a lot of organization to accomplish that kind of vanpool system.”
A portion of the reevaluation that reviews projects’ effects on historic and archaeological resources found the roadway would have an adverse effect on the historic Berger Cabin, which is perched above Castle Creek next to where the new roadway would connect with Main Street. The 1998 decision originally found it would have no impact on the Berger Cabin.
The cabin at 835 W. Main Street is a 988-square-foot log cabin built in 1947 and designed by architect Frederic “Fritz” Benedict. It was placed on the National Historic Register of Places in May 2025.
“What that means for the larger reevaluation process is, when we have adverse effects to historic properties, it kicks off processes and procedures, they require time, they require more consultation,” Clarke said. “We need to prepare a memorandum of agreement … to document measures to mitigate the adverse effects to the cabin.”
The roadway would be about 73 feet wide with a 10-foot sidewalk when it connects to Main Street. Deputy City Manager Tyler Christoff told the city council he does not think there’s a scenario “in which we can narrow it up enough to avoid [impacts to the Berger Cabin].”
The project team still has several months before it plans to send a draft reevaluation for CDOT and FHWA review. Clarke said he estimates the draft will be sent to CDOT in late April and to FHWA in late May, with an expected decision on the reevaluation by July 7.
In a Historic Preservation Commission meeting on Wednesday, commissioners showed staunch opposition to potential impacts the new roadway would have on the historic Berger Cabin.
HPC was asked to recommend acceptable mitigation measures for impacts to the Berger Cabin, and other historic properties that weren’t determined to be impacted under the federal standards but that the community might have more interest in mitigating further, Christoff said. The Holden Smelter and Milling Complex was determined under federal standards to not see impacts with the new roadway, but the city wanted HPC input on that structure about whether they wanted more screening for impacts, or other support to protect that site and others.
But HPC members argued that some mitigation efforts — like relocating the Berger Cabin — would defeat part of the purpose of what made the cabin historic in the first place.
They also argued that the impact to historic sites was measured against a roadway design that is still in the schematic phase and could potentially see changes in its final iteration. HPC member Roger Moyer called the request “insanity.”
“You’re asking us to approve a mitigation — we’ve given up, you’re destroying historic resources,” said HPC member Roger Moyer. “We want to go to the city and say, ‘This is insanity.’”
Gillian White, Aspen’s historic preservation officer, said the request of HPC is to help preserve the city’s historic resources to the best of its ability.
“My understanding … is that we’re not, I’m definitely not, the decision-maker on where the road goes,” White said. “Obviously it’s impacting the cabin significantly to where it’s going to need to be taken down, so if we have the opportunity to do what we can to save it, even though it’s not going to be in the same spot and have the same setting and same integrity that it has now, we should take that opportunity because we don’t have the decision to not impact it.”
HPC Chair Kara Thompson wanted to draft a letter for the project team outlining the commission’s opposition to changes to the Berger Cabin and other impacts to the city’s historic properties and historic district. Commissioners will review the letter during their Oct. 14 meeting.