Colorado overpass cuts wildlife crashes by 91%
Colorado wildlife overpass cut vehicle-animal collisions by 91%, report finds
Monday, 19 October 2026
Photo by teerapat mahingsa on Unsplash
Warm-up
- Where have you seen roads affect wildlife in your area?
- What makes roads dangerous for animals and people?
- How could a city reduce crashes without slowing traffic too much?
Vocabulary
- overpass
- A bridge built over a road so people or animals can cross safely above traffic.
- habitat
- The natural place where an animal or plant normally lives.
- collision
- A crash when two things hit each other, such as a car and an animal.
- corridor
- A long route that connects areas so animals can move between them.
- span
- To extend across something from one side to the other.
- funding
- Money provided for a project or purpose.
- infrastructure
- Public systems and structures like roads and bridges that a society uses.
- threatened
- At risk of becoming endangered or disappearing in the future.
Reading
Listen to this story
British EnglishColorado’s new wildlife overpass, which sits on Interstate 25 between Denver and Colorado Springs, has sharply cut crashes. A state report says wildlife-vehicle collisions in this corridor are down 91% since the bridge opened 10 months ago.
The overpass, which spans six lanes of traffic, links 39,000 acres of habitat on both sides. It is covered with grass and has gently sloped entrances to help animals cross.
Officials have tracked elk, bears and pronghorn using the crossing. The threatened Preble’s meadow jumping mouse has also been recorded.
Colorado’s transport department says there used to be about one collision a day here. Underpasses often fail for large animals, which prefer open views, so an overpass was chosen.
The project had $22m in federal funding and $8m from the state, and was completed for $15m. Supporters argue such infrastructure can pay for itself by preventing costly crashes. Officials now hope to build more crossings around the state.
Comprehension
- What percentage drop in collisions did the report find?
- Where is the overpass located in Colorado?
- How much habitat does the bridge connect?
- Name two animals that have used the crossing.
- How much did the project cost to complete?
Grammar focus
Relative clauses (non-defining)
Use commas to add extra, non‑essential information: , which/who + clause ,. Use which for things and who for people; that is not used in non‑defining clauses. (Examples constructed.)
- The overpass, which is covered with grass, blends in.
- Officials, who hope to build more crossings, welcomed it.
Grammar exercise
Circle the correct option in each sentence.
- The overpass, (which / that) is grass-covered, looks natural.
- Officials, (who / that) tracked elk, shared videos.
- The crossing, (that / which) links habitats, helps animals.
- Large mammals, (that / which) prefer open views, use it.
- Supporters, (that / who) argue it pays, back more builds.
Discussion
- Should governments invest more in wildlife crossings? Why or why not?
- Are overpasses better than underpasses for large animals? Explain.
- What evidence would show a crossing has succeeded?
- Where in your country could a crossing like this help?
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