Saving the Bear Lake Plateau Herd: New Wildlife Crossings Coming to U.S. Highway 30
For decades, a treacherous stretch of U.S. Highway 30 near Montpelier, Idaho, has served as a deadly bottleneck for one of the state’s largest mule deer herds. However, a major infrastructure project at Rocky Point is set to change that. By combining strategic underpasses with miles of specialized fencing, the Idaho Transportation Department (ITD) aims to slash wildlife-vehicle collisions and secure a critical migration corridor.
- The Project: Construction of three wildlife underpasses and six miles of 8-foot-tall fencing at Rocky Point.
- The Goal: To reduce the 70% of mule deer collisions that occur within a specific four-mile stretch of Highway 30.
- Funding: The project is supported by $20.8 million in federal grant funding.
- Impact: Protects the 20,000-animal Bear Lake Plateau mule deer herd and increases driver safety.
The Danger at Rocky Point
The stretch of U.S. Highway 30 south of Montpelier is a high-conflict zone for motorists and wildlife. Every year, approximately 100 mule deer are killed across a 20-mile section of the highway. The vast majority of these deaths are concentrated at Rocky Point, a four-mile segment (milepost 443-447) where about 70% of the collisions occur according to the Idaho Transportation Department.
This area is not just a random crossing point; it is a critical link in a regional migration route. The Bear Lake Plateau mule deer herd, consisting of roughly 20,000 animals, spends its summers in Wyoming’s Star Valley and Idaho’s Caribou Mountains. To reach their winter habitats northeast of Bear Lake, approximately one-third of the entire herd must cross Highway 30 at Rocky Point as reported by the Greater Yellowstone Coalition.
Engineering a Solution: Underpasses and Fencing
To mitigate these collisions, the ITD and the Idaho Department of Fish and Game are implementing a comprehensive crossing system. Rather than relying on signage alone, the project uses physical infrastructure to guide animals away from traffic.
Structural Components
The project includes the installation of three distinct wildlife underpasses:
- Two concrete box culverts designed for animal passage.
- One bridge to allow larger movements of the herd.
The “Funnel” Effect
Underpasses only work if wildlife uses them. To ensure this, the ITD is installing six road miles of 8-foot-tall wildlife fencing. This fencing acts as a guide, “funneling” migrating deer toward the underpasses and preventing them from entering the highway lanes per ITD project specifications.
Funding and Strategic Partnerships
This large-scale effort is made possible through significant federal investment and local conservation work. The ITD secured $20.8 million in federal grant funding through the Federal Highway Administration’s Wildlife Crossings Pilot Program via GYC.
Beyond government funding, private conservation played a pivotal role. In 2019, the Greater Yellowstone Coalition (GYC) donated $100,000 to help the Idaho Department of Fish and Game purchase conservation easements at Rocky Point. These easements ensure that the land on both sides of the crossings remains open to wildlife, preventing future development from blocking the migration route according to GYC.
Looking Ahead
With construction anticipated in 2026, the Rocky Point Wildlife Crossing represents a long-awaited victory for both the Montpelier community and local wildlife managers. By removing a primary bottleneck in the Bear Lake Plateau migration, the project will significantly increase driver safety and ensure the long-term survival of one of Idaho’s most significant mule deer populations.
Frequently Asked Questions
Why is Rocky Point so dangerous for deer?
Rocky Point is a critical bottleneck where approximately one-third of the 20,000-animal Bear Lake Plateau herd must cross U.S. Highway 30 to reach winter habitats.
How many deer are killed in this area annually?
About 100 mule deer are killed along a 20-mile stretch of US-30 south of Montpelier each year, with 70% of those deaths occurring at Rocky Point.
What exactly is being built?
The project consists of three wildlife underpasses (two concrete box culverts and one bridge) and six miles of 8-foot-tall fencing to direct animals safely under the road.