Strategy Spotlight: U.S. 97 Wildlife Crossing – Oregon

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Strategy Spotlight: U.S. 97 Wildlife Crossing – Oregon

Wildlife Passage Structure on Highway 97 in Central Oregon. Photo Credit: Simon Wray, ODFW
Wildlife Passage Structure on Highway 97 in Central Oregon. Photo Credit: Simon Wray, ODFW

 Oregon Conservation Strategy, January 2020

In June 2012, the Oregon Department of Transportation (ODOT)  completed an $18.9 million project on 3.7 miles of U.S. Route 97  between Lava Butte and South Century Drive, a few miles south of Bend in  Central Oregon. The project’s primary purpose was to increase highway  capacity for growing traffic volume between Sunriver and Bend by  expanding the single north/south travel lanes to two lanes in each  direction.

When plans for the highway upgrade began to  take shape in 2005, it was soon recognized that widening the highway  would significantly impact wildlife movement. This included thousands of  mule deer that move seasonally from the Cascade Mountains west of U.S.  97 to sagebrush flats and pine/juniper forests east of U.S. 97 and back  again. There is insufficient forage to support the mule deer herd  year-round on either side of the highway, so the bi-annual migration  across U.S. 97 is biologically necessary.

ODFW, the United States Forest Service (USFS), and ODOT worked together to tackle this problem. The group designed a suite of  wildlife passage structures to provide safe highway crossings for mule  deer and other wildlife.

 (Continue to article to see video of the wildlife crossing in action)

These structures include one underpass designed for wildlife use  only, and one underpass for both wildlife use and for vehicles driving  between the USFS Lava Lands Visitors Center west of the highway to the Lava River Cave on the east side.

Fences were built paralleling the highway that funnel animals to the  underpasses. For those animals finding themselves on the wrong (highway)  side of the fence, structures called “jumpouts” enable them to get back  behind the right (safe) side of the fence. Electric solar-powered mats  were installed across all roads that access U.S. 97 within the project  area. These access points are essentially holes in the fence, but the  low voltage mats quite effectively keep deer and other wildlife away  from the U.S. 97 and on the safe side of the fence.

Monitoring of the completed structures began in 2013. Within the  first year, 29 species ranging from deer and elk to bobcat, badger, and  squirrels were documented using the underpasses, and deer/vehicle  collisions were reduced by more than 90 percent. This is an obvious win  for both wildlife and the traveling public.

Addressing the wildlife passage problem within the highway expansion  area involved a substantial upfront investment of tax dollars. However,  considering the project’s success in reducing deer/vehicle collisions,  the average cost of a single deer/vehicle collision in the U.S. ($6,633  in 2012), and that the structures will provide benefits for 50 to 75  years, it made good economic sense to address wildlife. The upfront  costs are expected to be recouped in 10 to 12 years, and from that point  on, the project will continue in the green for decades to come.

The enhanced ability of wildlife to move across the highway barrier  is a great biological return on investment. Protecting and/or enhancing  the ability of wildlife to move across the landscape is critical for  healthy and vibrant ecosystems.

Continue reading here.