Traffic calming
Traffic calming is a set of strategies used by urban planners and traffic engineers which aims to slow down traffic and improve safety for pedestrians and bicyclists.
A major reason for traffic calming is to make it easier for pedestrians to cross safely, but there are other results from this strategy. It reduces traffic, promoting the use of altenative routes. It also reduces the noise and local air pollution which are side effects of the traffic.
Displaced traffic is not totally pushed onto other routes, as some travellers begin to walk or use other modes such as public transit and bicycles to get where they are going.
It should be noted the some of these measures (including speed bumps and choke points) have a tendency to irritate and annoy drivers rather than calm them and others (including roundabouts) can actually increase traffic throughput. Some drivers who slow down at calming points, however, accelerate and speed after passing them in order to "catch up for lost time".
Types of traffic-calming measures
Traffic calming can include the following specific techniques:
- Speed bumps, sometimes split or offset in the middle to help emergency vehicles reduce delay
- Roundabouts
- Chicanes
- Raised crosswalks or other styles of pedestrian crossings
- Pedestrian refuges or small islands in the middle of the street
- changing the surface material or texture (for example, the selective use of brick or cobblestone)
- Special lanes for bicycles, buses, or carpools
- New stop or yield signs
- Creating one-way streets from two-way streets
- curb (or kerb) extensions which narrow the width of the street
- Choke points, which are curb extensions which result in a single lane
- Allowing parking on one or both sides of a street
- Converting an intersection into a cul-de-sac or dead end
- Closing of streets to create pedestrian zones
- Reducing and enforcing speed limits near institutions such as schools and hospitals
- "Slow down" signs that flash when a driver exceeds the speed limit.
