What Are Curb Extensions or Bulbouts?

Curb extensions, sometimes called bulbouts, extend the sidewalk or curb line into the parking lane near a crossing. They shorten the distance a pedestrian spends in the roadway and improve sight lines between pedestrians and drivers.

How do they improve a crossing?

By moving the waiting pedestrian closer to the edge of moving traffic, a curb extension can make the person easier for an approaching driver to see. The shorter crossing also reduces the time a pedestrian is exposed to traffic.

Do curb extensions slow traffic?

They can visually and physically narrow the roadway at the crossing, which can encourage lower turning and approach speeds. Their main effect, however, is to improve the geometry and visibility of the crossing.

What has to be considered?

Drainage, snow removal, bicycle movement, parking, turning vehicles, emergency access, and the width and function of the road all matter when determining whether a curb extension fits a location.

Policy context

Sam's platform supports improved intersections and safer pedestrian crossings. Curb extensions are one design tool that can be considered where shorter crossings and better visibility are needed.

Research basis: Zegeer et al. (2005); Ewing & Dumbaugh (2009); Huang & Cynecki (2000).

Pedestrian visibility → · Raised crosswalks →