"Curb Extensions" is a group term, which can apply to chokers and slow points, semi-diverters, and bulb-outs. The term is most often used at pedestrian crossings - both at intersections and mid-block, where the extension of the curb into the roadway narrows the distance between curbs and improves the pedestrian environment. Visibility is also improved for both pedestrians and drivers.
At intersections they can be used to control traffic flow by preventing vehicles from passing turning vehicles. Landscaping can be applied to the extended curb. However, some parking may be lost and bike lanes may need to be terminated prior to the extension.
Culver City, CA
Manhattan Beach, CA
Creates more pedestrian friendly intersection.
Reduces pedestrian crossing distances.
Reduces speeds at location if travel lanes reduced sufficiently.
Widely used traffic calming measure.
Can be expensive if landscaped.
May affect buses or larger vehicles if intersection radii are tightened.