Department of Transportation Scott Kubly, Director
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Curb Bulbs

Curb bulbs extend the sidewalk into the street, reducing the time and distance it takes a pedestrian to cross. Curb bulbs can also prevent drivers from parking in front of crosswalks or blocking curb ramps. The visibility between drivers and pedestrians is also improved with curb bulbs because pedestrians are brought farther out into the street, making crossing locations more recognizable.

Preliminary data suggests that curb bulbs may serve to reduce vehicle speeds by narrowing the roadway. Curb bulbs might also help reduce vehicle-turning speeds if they reduce the turning radius. Another benefit of curb bulbs is the additional space that they often provide. Adding a curb bulb may allow for two curb ramps where previously only one was possible. At locations where an Adult Crossing Guard or a student School Patrol assists students in crossing the street, the additional space provides more room for guards to have students wait.

Where are curb bulbs appropriate?

In all cases, on-street parking without peak-hour restrictions is required on the side of the arterial street with the proposed curb bulb. Curb bulbs should not extend more than six feet into the street, in order not to interfere with the movement of bicyclists. In addition, curb bulbs are typically not recommended if there is a possibility of a future parking restrictions or additional traveling lanes, or if there is a bus stop in the vicinity (such that the bus may hit the curb bulb when coming towards, or away from, the curb).

In most cases, curb bulb feasibility is high in locations where there are other curb bulbs within three blocks on the same arterial street. Locations without curb bulbs within three blocks on the same arterial street will require a feasibility determination.

Click here for more information on how to get funding for curb bulbs and other neighborhood improvements

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