Montana Department of Transportation


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Public Involvement

York Road Roundabout

York Road Roundabout project logo

Project Overview

map that shows York Road roundabout lcoation
Click to view a larger image of the map.

The Montana Department of Transportation is constructing a roundabout at the intersection of York Road and Lake Helena Drive. The project will improve safety and operations of the intersection. Construction is anticipated to begin in April and be completed by fall 2019.

  • From January 1, 2003 to August 5, 2015 there were 28 recorded crashes in this area.
  • The majority of crashes occurring at this intersection were the result of drivers failing to yield and causing a right-impact collision.

The new roundabout will be a single-lane design with 12-foot lanes and four-foot shoulders. In addition:

  • The roundabout will feature LED lighting, curb, gutters and landscaping in the center median.
  • The design also includes a “truck apron,” which is a slightly raised surface which will allow large trucks to make turns.
  • The speed limit entering the roundabout will be 15 mph.
  • The roundabout will be constructed of concrete.
York Road roundabout

Why a Roundabout?

The York Road Roundabout will provide multiple benefits to motorists in the area while addressing safety concerns at the York – Lake Helena intersection. Studies by the Insurance Institute for Highway Safety (IIHS) and the Federal Highway Administration show that roundabouts typically achieve:

  • A 37 percent reduction in overall collisions.
  • A 75 percent reduction in injury collisions.
  • A 90 percent reduction in fatality collisions.
  • A 40 percent reduction in pedestrian collisions.

Additionally, roundabouts provide a traffic calming effect while promoting a smooth flow of traffic.


A detour south of the intersection will reduce commute times by allowing traffic to bypass the construction zone. The detour will remain in place until construction is completed in fall 2019.

What to expect:

  • Two lanes of traffic will remain open.
  • Motorists will drive on gravel surfaces.
  • Traffic will be controlled by stop signs.
  • Speed limit will be reduced to 25 MPH.
map that shows York Road detour
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