The People's Way
US 93 - Wildlife Crossing Structures in Use
The US Highway 93 (US 93) reconstruction projects from Hamilton to Lolo in the south and Evaro to Polson in the north combined represent the most extensive wildlife-sensitive highway design and construction effort in both road length and number of crossing structures in North America. These projects reconstruct over 76 miles of road and include the installation of 81 fish and wildlife (large and small animal) crossing structures, including one overpass; over 9 linear miles of wildlife exclusion fencing on both sides of the road; and numerous installations of wing fencing throughout this corridor.
These mitigation measures are aimed at improving safety for the traveling public by reducing wildlife-vehicle collisions and allowing wildlife to move safely across the landscape and the roadway. The landscape along US 93 is heavily influenced by human use, which is in contrast to the more natural vegetation along most of the other road sections that have large scale wildlife mitigation in North America. The magnitude of the US 93 reconstruction projects and associated mitigation measures provide an unprecedented opportunity to evaluate the effectiveness of mitigation measures in improving safety through a reduction in wildlife-vehicle collisions and maintaining habitat connectivity for wildlife (especially deer and black bear), while also evaluating the cost/benefit for the mitigation measures.
Post-construction research is underway along these two sections of roadway. The US 93 South project covers the 25 miles between Hamilton and Florence, and includes 19 large mammal structures, two separate locations of approximately one mile stretches of wildlife fencing on both sides of the road and multiple wing fencing installations. This project will be completed in 2015.
The preconstruction evaluation for the US 93 North project, Evaro to Polson, was completed in 2007 and is currently undergoing a post-construction evaluation (2010 – 2015). This corridor is over 41 miles in length, excluding the Ninepipes section, and includes 41 wildlife crossing structures, nearly seven linear miles of exclusion fencing on both sides of the road, and approximately 1.5 miles of wing fencing at nine different crossing structures.
In addition, small mammal use of culvert crossings research was conducted from 2001 to 2004 for 12 culverts on a previously reconstructed portion of US 93 South from Lolo to Florence.