US 34 Big Thompson Canyon

US 34 - Damage

Latest Updates

The Colorado Department of Transportation permanent repairs to US 34 between Loveland and Estes Park following the 2013 floods will begin after the Fourth of July holiday, but impacts to traffic will be relatively minor until after Labor Day.

“We expect this to be a low-impact summer for construction traffic as we begin work in the canyon,” said James Usher, CDOT project manager.  “CDOT is reducing construction activities occurring before Labor Day in order to reduce impacts to traffic during this summer’s peak tourist season.”

Prior to Labor Day, rock blasting is planned to take place at the “horseshoe curve” about three miles east of Drake (Mile Point 78.4). Generally, there will be only one blast per day during the work week. During this time, traffic will need to be stopped momentarily (15-30 minutes) while the actual blasts are conducted. The schedule of these blasts will be communicated weekly and updated every 24 hours, so travelers can plan.

Communication is an integral part of the project and we would like the public’s input on various traffic management options being considered as part of this project. Click here to review the public meeting presentation and a chart of these options along with the information boards displayed at the April 2016 meetings. You will also find a comment sheet to download, fill out and email to [email protected] to provide input on these traffic management options.

After the Labor Day holiday, rock-blasting work will begin near Idylwilde (MP 77.5) that will require more substantial traffic impacts including full closures of various durations throughout the day.

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 while 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 RepairsTemporary repairs were completed and the highway was reopened to traffic in both directions on Thursday November 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.

Click here to see a brochure that further explains the permanent repair process.

Estimated Timeline

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

Estimated Budget

  • >$50 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.

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