Safe Streets Arlington Plan Safe Streets Arlington Plan | Seite 118

INTERSECTIONS & ROADWAYS INTERSECTIONS & ROADWAYS

A roundabout is a type of circular intersection in which road traffic is permitted to flow in one direction around a central island , and priority is typically given to traffic already in the junction . The types of conflicts that occur at roundabouts are different from those occurring at conventional intersections ; namely , severe conflicts from crossing and left-turn movements are not present in a roundabout . The geometry of a roundabout forces drivers to reduce speeds as they proceed through the intersection ; the range of vehicle speeds is also narrowed , reducing the severity of crashes when they do occur . Pedestrians also only have to cross one direction of traffic at a time at roundabouts , thus reducing exposure to vehicle traffic .

Rumble strips create noise and vibration inside the vehicle that alert a driver as they cross the centerline or edge line . Treatment can help with lane keeping instances where a driver is distracted or drowsy . Rumble strips also alert drivers to the lane limits when conditions such as rain , fog , snow , or dust reduce driver visibility .

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Low Cost / Quick Build alternative available

Relevant Crash Types Left Turns at Signalized Intersections Left Turns at Unsignalized Intersections Angled Crashes at Signalized Intersections Angled Crashes at Unsignalized Intersections Speed Management

Relevant Crash Types Nighttime Wet Conditions Run Off Road Sideswipes Fixed Object

APPENDIX B : COUNTERMEASURES TOOLBOX B-19