Wildlife Bridges: The Animal Friendly Infrastructure

How many times have you had to slam on the breaks because an animal ran into the road? And how many of those times have your reflexes not been quick enough? Roadkill is a tragic reality of today’s car culture. According to Co.Design, vehicle-animal collisions cost Americans a massive $8 billion a year. That’s one expensive reality; however, innovative design can help.

In 2010, Balmori Associates, a New York City landscape design firm, proposed building simple, inexpensive wooden bridges over highways, then covering them in native vegetation to create a wildlife crosswalk. Each bridge would be so wide and the greenery so diverse, it would appear like an extension of the forest, and animals, the thinking goes, would be less inclined to cross the road, resulting in fewer accidents (Kuang, Co.Design). Following this proposal, Balamori Associates came up with the ARC International Wildlife Crossing Infrastructure Design Competition which was the “first-ever international design competition…intended to solve the problem of ensuring safe travel for humans and wildlife” (Kuang, Co.Design). The main idea is to keep the bridge as low-tech and cost-effective as possible so it can be constructed anywhere in the United States without disrupting the road or the environment. 

ARC—Animal Road Crossing—is an interdisciplinary partnership working to expedite new ways to create wildlife crossing structures. ARC’s primary goal is “to ensure safe passage for both humans and animals on and across our roads” (arc-solutions.org). These wildlife crossings or bridges will extend wildlife corridors and enable a variety of species safe passage across America’s highways. In other words, “ARC is working toward the (re)design of our highways so that the need for safe passage is met safely and efficiently while also maintaining the integrity and connectivity of our ecosystems, reducing our carbon footprint, minimizing the consumption of non-renewable materials, recycling resources and extending the life cycle of transportation infrastructure” (arc-solutions.org).          

An interesting fact, one that I was not aware of,  is that most of North America’s major highways generally go east-west while most wildlife movements tend to follow major landforms and topography which generally run north-south (arc-solutions.org) therefore increasing the need for wildlife crossings. When the proposed wildlife crossing structures are designed and built correctly they “act as a new, visible layer of functioning landscape, weaving over and under our highways, in and out of the natural landscape” (arc-solutions.org). Given the range and variety of species throughout North America, each wildlife crossing needs to cater to the specific needs of the species it is designed to protect. For example, some species prefer overpasses, while others prefer underpasses.              

When building wildlife bridges it’s important to remember that they are “typically shorter in span but much wider [than vehicle bridges]. They also necessarily include a thick layer of soil and vegetation—a landscaped surface—that must emulate local habitats” (arc-solutions.org). ARC recommends an inverted arc shape to the wildlife bridge because it conveys the feeling of a valley for animals and results in more light for drivers. Another aspect of the wildlife bridges is education; viewing platforms for the public to actually observe animals crossing the wildlife bridges at a safe distance will encourage support among the public. If people can see what the bridge is protecting they will be more inclined to encourage it.  ARC emphasizes that “wildlife crossings are being designed as living experiments, complete with data-gathering technologies built into the structure. Wildlife crossings offer rich potential for learning: infrared cameras installed at crossing sites capture and record animals in transit; web cams transmit real-time wildlife movement data to science labs and classrooms alike; and hand-held applications [such as smartphone apps] bring the data to passengers in a passing car” (arc-solutions.org). 

If we can manage to get large numbers of these wildlife crossings built, they could reduce animal-vehicle collisions between 80 and 100 percent if designed correctly; with time, ARC believes wildlife crossings can eliminate the problem and the cost of such collisions entirely (arc-solutions.org). Good news is, wildlife crossings may be closer than you think. President Obama just signed a transportation bill on July 6, 2012 that “includes important provisions that will allow states and federal agencies to retrofit roads and create wildlife crossing structures that help prevent wildlife from colliding with the motoring public. The wildlife-vehicle collision provisions address roads on federal and tribal lands, national parks, and state highways” (arc-solutions.org/news)

One easy way to help ARC understand where wildlife vehicle collisions occur most is to go online and share your Road Story here.

Also, to see examples of camera trap photos of animals using the wildlife bridges please visit here.

Reference:

“Can a Wildlife Bridge Fix America’s $8 Billion Roadkill Problem?” Co.Design. Ed. Cliff Kuang. N.p., 02 Dec. 2010. Web. 31 July 2012. http://www.fastcodesign.com/1662800/can-a-wildlife-bridge-fix-americas-8-billion-roadkill-problem.