CDOT Improves Safety on US 550 South of Durango

August 16, 2011 - Southwestern Colorado/CDOT Region 5 - Some travel impacts on CR 302, minimal impacts on US 550 this season.

LA PLATA COUNTY – The Colorado Department of Transportation is improving a section of US 550 south of Durango. The project, which lies north and south of La Plata County Road (CR) 302 (between mile posts 11.3 and 12.8), involves major reconstruction with intersection safety improvements and a new four-lane divided highway through this stretch.

Work includes excavation and new roadway construction, new right-of-way and wildlife fencing, a wildlife detection system at the fence ends, wildlife escape ramps and guards, and drainage improvements. The project was contracted to Old Castle SW Group Inc. of Grand Junction for $4.77 million.

HIGHWAY RECONSTRUCTION: The project will construct a new four-lane highway divided by a center grass median (ranging in width from 16 to 36 feet, depending upon highway travel lanes) to the east of the current alignment. The construction schedule has crews building the two new northbound lanes this year. Next year, all traffic will be switched onto the new lanes, then crews will build new southbound lanes, using recycled road base material from the existing US 550 roadway.

The four-lane highway will also get auxiliary lanes:  southbound left-turn and northbound right -turn lanes on US 550 and a left‐turn acceleration lane onto southbound US 550 from westbound CR 302.  Amber LED flashers will be added to existing intersection warning signs to help get drivers’ attention.

“I am very pleased to see this work underway,” State Transportation Commissioner Steve Parker said. “This intersection at CR 302 is ranked number five in Region 5’s Intersection Analysis & Priority Study*; the improvements here will not only make this intersection safer, but will greatly enhance mobility along this heavily traveled stretch of US 550.”

WILDLIFE FEATURES: The wildlife/driver safety features include construction of 6,200 linear feet of eight-foot-high wildlife fence (about 3,100 feet on each side of the highway); four wildlife escape ramps (one-way earthen ramps adjacent to the fence whereby animals can exit the highway right of way); five “deer guards” at highway access points; and a buried cable detection system at each fence end. (This type of detection system was first installed on US 160 east of Durango in 2009 and is achieving marked success to date.) An underground cable buried on either side of the roadway detects changes in the earth's electromagnetic field. The presence of large animals (deer, elk, horses) crossing this cable will trigger detection by the system. The system then transmits information to a sensor module that will activate electronic signs to warn motorists of wildlife in the roadway’s vicinity. This system will be placed at each end of the wildlife fencing—with three dynamic signs at each end—to reduce the potential for wildlife-vehicle collisions in those areas.

“The most successful wildlife crash measure that has been proven to work in highway settings is wildlife fencing,” CDOT Traffic & Safety Engineer Mike McVaugh said. “The electronic detection system adds a benefit to large wildlife—and motorists—near areas where there are gaps in fencing to allow normal migration to occur. Wildlife fencing alone is not a viable option where there are known migration routes.”

TRAVEL IMPACTS: Work hours are Monday through Friday during daylight hours (30 minutes after sunrise to 30 minutes before sunset). Motorists can expect single-lane, alternating travel on both US 550 and CR 302—delays are expected to be less than five minutes on US 550 during this first season, possibly a bit longer on CR 302. County Road 302 will be open at all times. (Travel delay updates will be sent as the work progresses.) The project will be completed in July 2012, following a winter work suspension. Thank you for going Slow for the Cone Zone!

PROJECT INFORMATION: For additional information or questions about the project, the public may contact Marty Punchak at (970) 247-2172. Updated information regarding traffic impacts on this or other CDOT projects is available at or by calling 511. To receive project updates via wireless device or e-mail, visit and click on the green cell-phone icon in the upper right-hand corner. The link takes you to a list of items/areas you can subscribe to.

*CDOT Region 5’s current Intersection Analysis & Priority Study (2008) investigated safety, geometric and operational characteristics at 33 intersections throughout the 13-county region (the study is updated about every five years). The top 5 intersections on the list are the following:

  1. US 50 at Holman Avenue in Salida (signal has been installed)
  2. US 491 at Montezuma CR M in Cortez (safety improvements are complete)
  3. US 145 Society Turn in Telluride (2012 project)
  4. US 160 at Cat Creek, west of Pagosa Springs (currently in design)
  5. US 550 at La Plata CR 302 (under construction)