Bid Awarded for Building Wildlife Underpass (June 9, 2010)

by June Sparks, Idaho Transportation Department

BOISE — Commuters and outdoor recreationists aren’t the only ones who traverse Idaho 21 along what is known as the Ponderosa Pine Scenic Route. Each year, large numbers of deer and elk are killed as they attempt to cross the highway.

In early July, The Idaho Transportation Department (ITD), with support from the Boise River Wildlife Linkage Partnership (, a group of concerned citizens, businesses, non-profits and city, county, state and federal representatives, will build a wildlife underpass near milepost 18.2. The bridge and wildlife fencing will be constructed to help get deer and elk across Idaho 21, protecting people and wildlife. As additional funding becomes available, extending the wildlife fence on the east side of the underpass will increase the use and function of the structure.

Here is a link to ITD’s Facebook page where you can see pictures of the construction area as well as a rendering of what the finished underpass will look like.

“There are too many vehicle-wildlife collisions occurring on this stretch of highway,” said ITD environmental planner and biologist Scott Rudel. “Simply put, what it comes down to is that we can do a better job protecting people and protecting wildlife than what now exists. ITD and the Boise River Wildlife Linkage Partnership believe that this project is an investment for the people of Idaho in their safety, quality of life, and in protecting their natural and cultural resources.”

In just the past eight months, 69 vehicle-wildlife collisions have been posted on the “Give Deer and Elk a Brake” tally signs. Click here to see a tally sign. These signs reflect the number of incidents on an 11-mile stretch of Idaho 21 initiating from near Discovery Park at Lucky Peak Reservoir through the intersection of Robie Creek.

The high number of vehicle-wildlife collisions is due to the propensity of mule deer and elk that migrate in the fall from their summer range high in the Sawtooth and Boise Mountains to their winter range on the west slope of the Boise Front and do it all over again in reverse the following spring.

Federal stimulus funding is being used to construct the bridge and a portion of the fencing. McAlvain Construction is the contractor for the $756,000 project. Use of wildlife crossings have been on the rise in the United States with their proven ability to make the roads safer for people and wildlife.

“Physically separating motorists and wildlife is the best way to protect both,” said Ed Bottum, Wildlife Habitat Biologist. “The tally signs are there to remind motorists of the hazard posed by deer and elk on the highway. Only individual drivers can slow down accordingly. Currently, raising driver awareness is our only real option right now, but with this project we hope to change that.”

Construction of the wildlife underpass bridge will begin the first week of July and will be completed in early fall. Traffic will be re-routed around the construction area by way of a temporary bypass adjacent to the highway with temporary signals directing the flow of traffic.