COUNTERMEASURES

The following section addresses contributing factors associated with the prevalent crashes patterns on Shroyer Road and potential countermeasures to mitigate those crashes. Additional countermeasures are recommended to minimize potential safety issues that may not be directly attributed to historical crash trends.

SHROYER ROAD DIET – 80 CRASHES

A road diet is proposed to mitigate the 80 crashes within the City of Oakwood. A road diet is the conversion of an undivided 4-lane roadway to a 3-lane roadway made up of two through lanes (one each direction) and a center left turn lane with a raised median or two-way left-turn lane (TWLTL). The reduction of lanes allows the roadway cross section to be reallocated for other uses such as bike lanes and pedestrian refuge islands.

Traditional road diets involve the conversion of a 4-lane undivided cross-section to a 3-lane cross section which has 1 travel lane in each direction and a center turn lane. The introduction of the center turn lane removes turning traffic from through lanes and aligns left turning vehicles, removing sight distance obstructions from opposing left turn vehicles, and eliminating speed differential in the travel lanes. This results in consistent speeds on the corridor, reducing rear end crashes and left turn angle crashes. Due to the fact that a traditional road diet does not significantly impact capacity on the roadway, these applications may be used on roadways operating near capacity with the 4-lane cross section without significant operational impacts.

Benefits of road diets include the following:

  • traffic calming including reduced and uniform speeds;
  • improved safety performance;
  • improved pedestrian accommodation resulting from decreased crossing distance and slower vehicular speeds (e.g., passing by higher speed vehicles is not possible);
  • improved bicycle accommodations.

Four (4) lane, undivided roadways such as Shroyer Road experience a number of typical crash types as traffic volumes increase:

  • Rear end and sideswipe crashes caused by speed differential between vehicles;
  • Sideswipe crashes caused by frequent lane changing between two through lanes often due to stopped vehicles in the inside travel lane waiting to turn left;
  • Rear end crashes caused by left-turning vehicles stopped in the inside travel lane;
  • Angle crashes caused by side street traffic crossing four lanes to make a through movement across an intersection;
  • Left turn crashes caused by restricted sight distance obstructed by opposing left turning vehicles that are offset;
  • Bicycle crashes due to a lack of available space for bicyclists to ride comfortably; and
  • Pedestrian crashes due to the number of lanes for pedestrians to cross with no refuge.