US 34 Big Thompson Canyon

US 34 Between Loveland and Estes Park Open to All Traffic
Plan for up to 20-minute delays through winter

US 34 through the Big Thompson Canyon between Loveland and Estes Park is open to all traffic, marking the end of all long-term closures on a highway that has undergone major reconstruction since July 2016.

  As final work is done, however, drivers could encounter traffic stops in various parts of the canyon—between mile points 65 (Mall Road) and 85 (Dam Store)—for asphalt paving, sign installation, lane striping, guardrail installation and access bridge construction.

Because it's more efficient to have crews move from location to location to do their work while they're in the canyon, it's difficult to pinpoint exactly where guardrail, sign, paving and striping crews might be from one time of the day to the next. Given that multiple crews are working in multiple locations, people traveling all the way through the canyon should expect short-term stops as necessary to do this work. Total cumulative travel delays should not exceed 20 minutes, however.

Substantial completion of the project is scheduled for December 2018.

There are some seasonal work activities like landscaping that can't be done until spring 2019. This work could involve short-term lane closures. Thank you to canyon residents and businesses in Estes Park and Loveland for their patience and understanding through this flood recovery project.

Flood Impact Analysis

US 34 Big Thompson Canyon was heavily damaged during the 2013 floods, with many homes damaged and over 100 air-lifted evacuations. The canyon and its residents also suffered from flooding in 1976. As a result of these two events, CDOT has been studying the hydraulic flow of the river in the canyon, and its impact on the road and bridges along its path. CDOT also is looking for safety improvements and resiliency solutions to prevent and protect against significant damage from future flood events.

Damage Overview

This section US 34 winds its way through the Big Thompson Canyon, providing major access between Loveland, Lyons, and Estes Park. During the flooding, watershed runoff combined with flows released from Lake Estes Dam and surges from debris dam breaches to produce huge flow surges that exceeded the 500–year flood event. The canyon section sustained widespread, massive damage. Major sections of roadway were washed away completely, along with access bridges and retaining walls. In the narrows, much of the roadway and grade were undermined, washing out the pavement from below and exposing the wall support structures.

Emergency (Temporary) Repairs

US 34 - Emergency Repairs
Temporary repairs were completed and the highway was reopened to traffic in both directions on Thursday, Nov. 11, 2013. CDOT and its contractors worked from both the east and west ends of the canyon to assess and repair the damage and restore local access as quickly as possible. Emergency repairs were extensive and included removing debris, re-establishing shoulders and embankments, replacing damaged asphalt, filling washed out sections with concrete fill, repairing local access structures, and repairing damaged drainage structures.

Permanent (Long-Term) Repairs

Permanent repairs will include removing and replacing much of the temporary asphalt, embankment fill, and temporary channel protection; as well as re-vegetating, replacing guardrails, and repairing fencing. Some of the roadway sections that were not destroyed, but experienced flood water overtopping the roadway, will be analyzed and possibly replaced.

See a brochure that further explains the permanent repair process.

Estimated Timeline

  • Est. Design Start: Summer 2014
  • Construction Start: 2016

Estimated Budget

  • $280 million


One of the goals in the repair process is to introduce certain betterments (improvements that go beyond bringing the roadway up to standard) to roadway facilities that were damaged and make them more resilient to similar storm events in the future. Having analyzed the damage caused during the flood event, certain design elements will be incorporated in an effort to prevent or lessen the severe damage that significant flood events can cause. During the permanent repair phase, several alternatives will be developed to ensure that the Big Thompson channel has increased capacity and the roadway has additional high water relief to handle large storm events.

Colorado: The Official State Web Portal