US 285 Wildlife Underpass in Nathrop

Project Facts

  • Cost: $3.5 million
  • Contractor(s): SEMA Construction
  • Timeline: March 2018 - August 2018

Traffic Alert

Through August, there is a wide-load restriction on US 285 from approximately mile points 140 to 148.

Wide-load vehicles must use alternative routes.

Other Impacts

  • While construction is underway, motorized vehicles can expect one-lane closures.
  • Residents will have access to all properties with some delays expected. Average wait times are estimated to be 10 minutes.

On Monday, March 12, 2018, crews began constructing a wildlife underpass near the US Highway 285 and US 24 intersection to Nathrop.


Motorists have killed approximately 70 deer at this location in the last two years and close to 250 in the last decade. In fact, vehicle-wildlife collisions constitute as many as 70 percent of all reported crashes in this area.

Studies have shown that wildlife crossings, coupled with fencing, can reduce collisions by over 75 percent.

The Solution


  • The wildlife underpass will be approximately 85 feet long, 12 feet tall and 32 feet wide.

  • Deer fencing will also be installed, which will help channel the animals into the underpass. The eight-foot-tall fence will stretch approximately one-quarter mile south of the underpass and approximately one mile north of the underpass.

  • Additional features include:
    • "jump-outs," or wildlife escape ramps, which are one-way earthen ramps that animals can use to get back over the fence to safety.
    • deer guards (like cattle guards only wider), which will be installed at highway accesses and small mammal crossings under the highway. 
    • widening the highway to accommodate a new left-turn lane for southbound US 285 traffic turning onto County Road 301/Fisherman's Bridge.

Project Schedule

  • Work on US Highway 285 is scheduled to be completed in August 2018.
  • Normal working hours will be from 7 a.m. to 7 p.m., Monday through Friday. In special cases these hours may be extended.
  • Weekend work is not anticipated.

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