FIGURE 3: INTERSECTION FUNCTIONAL AREA

FIGURE 3: INTERSECTION FUNCTIONAL AREA diagram showing Intersection Conflict Overlap, Storage, Decel, Downstream, and Upstream regions

A review of the documented crash history on Shroyer Road within the City of Oakwood suggests patterns that are consistent with urban/suburban corridors having 4 lanes. The 4-lane section of Shroyer Road exhibits the following crash patterns:

  • Rear end crash. Vehicles stop to turn left in the shared left-through lane. Lack of attention by a following vehicle results in a rear end crash. Following vehicles that abruptly change lanes also contribute to following vehicles colliding with a stopped vehicle intending to turn left at an unsignalized intersection. Rear end crashes can also occur when a vehicle slows intending to complete a right turn movement. The percentage of rear end crashes are two times higher (42.8 percent) than the statewide average (20.7 percent)
  • Sideswipe passing crash. Sideswipe crashes occur when a lead vehicle slows to complete a turning movement at an unsignalized intersection. Following vehicles abruptly change lanes to avoid the need to slow or stop and collide with vehicles in an adjacent lane. The percentage of sideswipe passing crashes are higher (8.9 percent) than the statewide average (6.9 percent).

  • Right angle crash. Right angle crashes are attributed to sight distance obstructions. Sight distance is restricted by trees, fencing, landscaping, and embankment located behind the sidewalk. Intersection sight distance can also be restricted when an RTA bus is stopped to load/unload passengers in the curb lane thus blocking visibility of through traffic in the adjacent lane.

    A right angle crash pattern (4 crashes) also exists at the Peach Orchard Avenue intersection. The profile of Shroyer Road limits the sight distance of northbound vehicles. Vehicles turning from Peach Orchard Avenue are at fault for all right turn crashes since a No Left Turn sign (R3-2) is posted on the northbound approach.

Operational characteristics that contribute to the safety performance of existing Shroyer Road include higher operating speeds, more conflict points, and restricted sight distance of left turning vehicles on the major street.

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