Unsignalized Intersections Safety at Unsignalized Intersections

Unsignalized Intersections FHWA Safety Focus Areas 2

Unsignalized Intersections National Statistics 3

Unsignalized Intersections National Statistics 4 Non-Intersections 79% Intersections 21% There were 41,059 highway fatalities in Where did they occur? About half of all crashes and half of all injury crashes occur at intersections.

Unsignalized Intersections Intersection Fatalities 5 5,232 1, ,739 There were 8,657 intersection fatalities in Where did they occur? 39% in rural areas 61% in urban areas Fatalities

Unsignalized Intersections Intersection Fatalities 6

Unsignalized Intersections Intersection Safety Guidance NCHRP Report 500 Volume 5 Guide sheets Safety Strategies brochure 7

Unsignalized Intersections Typical Intersection Crash Types Right angle Rear end Left turn Sideswipe Pedestrian/bicycle 8

Unsignalized Intersections Crash Reduction Factors Quantitative results from research or other studies Expected reduction in crashes from implementation of a specific countermeasure 9

Unsignalized Intersections 10 Angle Crashes Account for 53% of fatal crashes at unsignalized intersections Clear sight triangles Improve awareness of intersection Apply access management Construct roundabouts Improve turn lane design

Unsignalized Intersections 11 Angle Crashes Also: Close/relocate intersections Post appropriate speed limits Acceleration Lane Through Lanes Construct acceleration lanes New alignment Reduce/eliminate skew Targeted enforcement

Unsignalized Intersections 12 Rear End Crashes Install turn lanes Supplemental overhead signing Provide shoulder bypass lanes Account for 6% of fatal crashes at unsignalized intersections

Unsignalized Intersections 13 Rear End Crashes Also: Construct roundabouts Provide left-turn acceleration lanes Provide lighting Post appropriate speed limits Improve intersection awareness Provide pavement markings Provide right-turn acceleration lanes

Unsignalized Intersections 14 Left Turn Crashes Account for 8% of fatal crashes at unsignalized intersections Improve turn lane design Implement turn restrictions Use indirect left turn treatments Also: Provide lighting Clear sight triangles Provide left turn acceleration lanes Construct roundabouts Close/relocate high-risk intersections

Unsignalized Intersections 15 Sideswipe Crashes Account for 2% of fatal crashes at unsignalized intersections Provide lane assignment signing or marking Also: Provide right-turn acceleration lanes Install pavement markings

Unsignalized Intersections 16 Pedestrian/Bicycle Crashes Account for 14% of fatal crashes at unsignalized intersections Improve facilities Information and education Provide traffic calming

Unsignalized Intersections 17 For More Information AASHTO Report 500 Series Volume 5 – Manual on Uniform Traffic Control Devices – Toolbox on Intersection Safety and Design – FHWA Office of Safety –