Descriptions and Pictures of

Traffic Calming Devices and Techniques

Devices and Techniques

Descriptions

Pictures

Bike Lanes

A portion of a roadway which has been designated by striping, signing, and pavement markings for the preferential or exclusive use of bicyclists.

Bulbouts/Neckdowns/

Chokers

Curb extensions at intersections that reduce curb-to-curb roadway travel lane widths.

Center Islands

Raised islands located along the centerline of a roadway that narrow the width at that location.

Chicanes/Lateral Shifts

Curb extensions that alternate from one side of the roadway to the other, forming s-shaped curves.

Closures (Cul-de-sacs)

Barriers placed across roadways to completely close through vehicle traffic.

Diverters

Barriers placed diagaonally across an intersection, blocking certain movements.

Education

Instructions given to the residents on safe on-street vehicle travel.

Forced Turn Lanes

Raised islands located on approaches to an intersection that block certain movements.

Median Barriers

Raised islands located along the centerline of a roadway and continuing through an intersection to block cross traffic.

Police Enforcement

Involve employing the services of law enforcement agencies to impose the local safe vehicle laws, including those for posted speeds and traffic signal/signs.

Realigned Intersections

Changes in alignments that convert T-intersections with straight approaches into curving roadways meeting at right angles.

Roundabouts

Barriers placed in the middle of an intersection, directing all traffic in the same direction.

Speed Humps

Rounded raised pavement devices placed across roadways to slow and/or discourage traffic

Speed Tables/

Textured Pavement/

Raised Crossings

Flat-topped speed humps often constructed with a brick or other textured material to slow traffic

Traffic Circles

Barriers placed in the middle of an intersection, directing all traffic in the same direction. Usually larger than roundabouts.