U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
202-366-4000


Skip to content
Facebook iconYouTube iconTwitter iconFlickr iconLinkedInInstagram

Safety

FHWA Home / Safety / Geometric Design / Publications / Mitigation Strategies For Design Exceptions

Site Constraints

 

The site constraints of the Tensleep-Buffalo Highway project area were the steep, mountainous terrain and sensitive environmental areas (Figure 85). Challenging soil and geologic conditions, including slide areas, were also present.

One of the major project stakeholders was the U.S. Forest Service, which is the steward of the Big Horn National Forest. The Forest Service requested that the project cause minimal disturbance or impact to vegetation, wildlife, aquatic life, waterways, and natural terrain formations within the forest. The surrounding area is an elk winter refuge and game migration route. Minimal disruption to recreational users of the forest was also requested.

Figure 84.  The Tensleep-Buffalo leads into the Big Horn Forest in the Rocky Mountains.

FIGURE 84

The Tensleep-Buffalo Highway leads into the Big Horn National Forest in the Rocky Mountains.

Figure 84 is a photo taken at the top of a steep downgrade with a magnificent view in the horizon.  This perspective illustrates the context of the area–very scenic, mountainous, tree–covered, and environmentally sensitive.

Alternative alignments were considered but were determined to be infeasible. Flattening the grades and horizontal curves to meet design criteria would have involved massive cuts into the mountains. The environmental impacts would have been severe and the construction costs exorbitant. For these reasons, the highway was essentially reconstructed along existing alignment.

Figure 85.  A massive retaining wall illustrates the difficult site constraints that were encountered.

FIGURE 85

A massive retaining wall illustrates the difficult site constraints that were encountered.

Figure 85 is a photo showing a high and long-running retaining wall along the canyon side of the highway.
 
Back to the Table of Contents
Page last modified on October 15, 2014
Safe Roads for a Safer Future - Investment in roadway safety saves lives
Federal Highway Administration | 1200 New Jersey Avenue, SE | Washington, DC 20590 | 202-366-4000