Vehicles can be the biggest predators of deer, elk, bears, and other wildlife. Engineers have been looking into new ways to design overpasses or "wildlife bridges" that allow wildlife to cross from one side of a major highway to the other. The benefits to wildlife are clear, but the bridges also cut down on the accidental death, injuries, and property damages that result from vehicle/wildlife collisions.
The Western Transportation Institute at Montana State University invited designers from around the world to come up with novel designs to span across Interstate 70 near Vail, Colorado. The Wall Street Journal has a write up about the new designs and their costs.