Georgia Designs Bridges That Save Wildlife and Stop Floods

Turtles cross roads looking for high ground to lay their eggs, and that simple fact just sparked a breakthrough that could save lives and money across America.

Researchers at the University of Georgia are tackling a $10 billion problem with an elegant solution. They're redesigning bridges and culverts to stop flooding while helping wildlife cross safely underneath roads instead of over them.

Professor John Maerz from the Warnell School of Forestry and Natural Resources leads the interdisciplinary team. He partnered with Brian Bledsoe, director of the College of Engineering's Institute for Resilient Infrastructure Systems, to rethink how we build road crossings.

The problem is massive. Drop a pin randomly in the eastern United States and you'll land within half a kilometer of a road. Animals need to move across landscapes to survive, whether they're turtles seeking nesting sites or turkeys finding safer habitats.

The team is analyzing where wildlife collisions and flooding happen most in Georgia. They're creating a tool to help decision makers choose the best locations for improved crossings. Then they'll design passages that handle intense storms while guiding both water animals and land animals safely under roads.

This isn't Maerz's first creative win against wildlife collisions. In 2022, his team discovered that diamondback terrapins died most often at certain times of day along the Georgia coast. Traditional turtle crossing signs weren't working.

Inspired by flashing school zone signs, Maerz worked with the Georgia Department of Transportation to create turtle signs that flash only when terrapins are most active. The signs worked, cutting turtle deaths in half.

The Ripple Effect

The new bridge designs will protect countless species from salamanders to white-tailed deer and coyotes. Each animal has unique needs, so the team must consider everything from how long a crossing should be on a multi-lane highway versus a country road to whether the passages might accidentally attract predators.

Working with GDOT engineers means these solutions will actually get built. The collaboration brings together ecology, engineering, and real-world infrastructure needs.

Bledsoe sees the complexity as opportunity. "There are huge costs, injuries, and deaths associated with wildlife-vehicle collisions and flooding," he said. "Not to mention it's a complex problem that requires us to work across disciplines and integrate knowledge."

The team draws inspiration from learning by doing, testing creative solutions to see if they actually work. When roads meet nature's needs instead of blocking them, everyone benefits.