Bahman Izadmehr

One of the main objectives of Traffic Calming (TC) is to reduce traffic speeds and traffic volumes to acceptable levels (Institute of Transportation Engineers (ITE) on Traffic Calming - www.ite.org). Under a broader European definition, “…More generally it can be said that traffic calming aims to alleviate the adverse effects of motorized traffic. Measures generally refer to local speed control and other measures of traffic restraint, but may, more widely, also include network planning, parking policies and stimulating the use of alternative transport modes…” Roadways with speed limit over 35 mph (50 kmh) include arterials, two-lane highways and multi-lane highways. The principal TC control measures that could be used for such roadways are: Gateways that designate a change in driving environment; roadway narrowing at places that have pedestrian and/or bicycle crossings or where a speed reduction is warranted; lane width of less than 11 feet to reduce both speed and/or traffic volume; capacity reduction to reduce through volume – a very drastic measure that could be used only at places where a good alternative exists for the diverted traffic; and Intelligent Transportation Systems (ITS) control measures such as speed cameras, intelligent adaptive cruise control and signalization. TC control measures should not be an obstacle to emergency vehicles such as EMS, Police and Fire Departments, and towing services. The community should be involved in all stages of any TC program to ensure that the public is educated; it provides input and provides support for such programs.