UDOT outlines new Mountain Green I‑84 interchange plan; officials, residents press emergency access concerns

Tyler Allen, UDOT environmental manager for the Mountain Green project, told the Morgan County Commission the agency is seeking to separate regional traffic on I‑84 from local travel within Mountain Green to reduce congestion and safety risks.

The proposed action would add a new interchange and signalized connections between I‑84, a new arterial and Old Highway 167 (Trappers Loop Road); remove the existing westbound on‑ramp and eastbound off‑ramp at Exit 92; and remove the existing I‑84 rest area. Allen said the project started with scoping in summer 2023, moved into an environmental assessment in spring 2024, and that a public comment period opened April 4 and runs through May 8 with an online meeting April 22 and an in‑person hearing April 23; UDOT expects to publish a decision in summer 2025.

Why it matters: UDOT staff said current conditions mix regional canyon traffic with local Mountain Green trips on roads not designed for that volume, creating congestion and crash risk. Jeff Erdman, UDOT project manager, told the commission the proposed interchange would create a larger‑capacity, more direct route for regional traffic and reduce heavy through traffic on SR‑167 and Old Highway Road.

Public safety concerns: Commissioners and local first responders pressed UDOT on emergency response and evacuation implications if Exit 92 ramps are removed. Commissioner Blocker said the proposed closure could “create a dead end road” for ambulance runs that originate in Morgan City; Chief Boyd Kerrigan of Morgan City Ambulance (represented in the meeting by commissioners) warned that closing the ramps could add roughly 10 minutes to some transports and urged further study. UDOT staff acknowledged mixed input from emergency responders at scoping; staff said their traffic and emergency response analysis (EA section 3.14) shows an overall improvement along SR‑167 and Old Highway Road and concluded closing Exit 92 yields better network performance in many peak periods but asked the county to submit ambulance call‑out data to the public comment record for additional review.

Federal spacing standard: UDOT told the commission an Interchange Justification Report required by Federal Highway supports closing Exit 92 because the proposed new interchange would lie northwest of Exit 92 at a distance that “does not meet federal rural spacing of 3 miles between interchanges”; staff noted some in‑state interchanges are closer but said federal safety and operational standards informed the recommendation.

Rest area and other features: UDOT staff said the I‑84 rest area near Exit 92 would be removed because the department’s evaluation found it does not function as intended; staff acknowledged the site contains a local monument (the Peter Ogden memorial) and said relocation details would be addressed during design. The plan would include trail connections and a bridge over the creek sized to allow trail use underneath.

Next steps: UDOT asked the county and residents to submit any additional data or concerns during the EA comment period. Commissioners encouraged UDOT to explicitly address ambulance response times in the administrative record and to evaluate interim measures raised by residents (for example, temporary barricades or alternative ramp configurations) even if federal guidance typically limits temporary ramp retention on interstate facilities.

Ending: UDOT staff said they will continue stakeholder coordination, incorporate public comments, and expect to publish a final decision in summer 2025. The county asked UDOT to add ambulance call volumes for Mountain Green to the EA record and indicated commissioners may forward additional input from local fire and ambulance chiefs as part of the official comment process.