Influence of road dimensions and on-street parking on vehicular speeds along residential streets

Speed is a simple measure that may be used to determine the efficiency of a road or road network that carries traffic. It is basically the total distance traveled by a vehicle divided by the time taken to traverse the distance. This movement is usually expressed in kilometers per hour (km/h). The selection of driving speed depends on the road width that can be effectively used while driving. Studies have shown that speed tends to be lower for narrower roads. For every 0.3 m increment in road width, the 85th percentile speed reduction is approximately 4.7 km/h. The length of road also affects the speed of the vehicle. Long, straight roads have been found to promote high-speed traffic. Thus, there is a need for conscientious design that limits the length of a road in order to restrict the amount of space that may ultimately be used by the driver to increase his speed