Traffic Calming – Frequently Asked Questions

Traffic Calming:

Traffic calming is the combination of mainly physical measures to reduce the negative effects of motor vehicle use. Various types of devices can be used including speed humps (not bumps), speed tables, raised pedestrian crosswalks, chokers, traffic circles, median islands, etc.

Do traffic calming measures affect emergency response times?

Studies have shown that certain traffic calming measures, especially vertical measures such as speed humps and raised crosswalks, can slow fire trucks and other emergency vehicles by about 3 to 10 seconds each. This impact will be additive with a series of measures.

Do speed humps affect snow removal?

Speed humps and raised crosswalks are gradually sloped so that snow plow blades go over without damage to them or the pavement surface.

Do speed humps create additional noise levels?

Studies have shown that some noise levels have increase where the total percent of heavy truck traffic volume is 20% or greater.

Do traffic calming measures affect property values?

There is no evidence to suggest that traffic calming measures either raise or lower residential property values. It is likely that for every person who feels they detract from the value of a property, there is another who feels their safety benefits add to the value of a property.

Can the speed humps on our street be made higher or lower?

Speed humps (and raised crosswalks) in Fairfax County are 12 feet and 22 feet long respectively, and 3 inches high. Research has found these dimensions to be the best compromise between being severe enough to slow most vehicles, yet forgiving enough to not unduly impact emergency response times.

Who develops and who has final approval of the traffic calming plan?

The development of a traffic calming plan is a community-driven process under the leadership of a traffic calming task force and the overall direction of the Fairfax County Department of Transportation (FCDOT). Traffic calming is a program of the Virginia Department of Transportation (VDOT) and administered in collaboration with FCDOT. The community task force has a significant role in the project approval. The community votes on the plan via a ballot process, to ensure that the traffic calming plan has widespread support across the community.