The term “traffic calming” has evolved from the German word “Verkehrsberuhigung.” It refers to the methods of changing the behaviour of the motorists in accordance with the characteristics of the area in which they move. These methods help to reduce vehicle speed, improve road safety and also enhance the quality of life. The Institute of Transportation Engineers defines traffic calming, ”as the combination of mainly physical measures that reduce the negative effect of motor vehicle use, alter driver behaviour and improve conditions for non-motorised street users.” These measures alter streets from both the visual and safety reasons and thus make the streets and urban areas more livable. Traffic calming is only a means to an end; and the end product being good living in a better environment.

Traffic calming measures

Traffic calming measures are classified according to their functions as given below:

i) Volume control (full closure, half closure, dead-end, one-way, diagonal diversion and median barrier)

ii) Speed control measures (speed humps, speed table, raised intersections and textured road surface). (Figure 1)

iii) Horizontal control measures (chicanes, traffic rotaries, redesigned intersections and lateral shift). (Figure 2)

iv) Narrowing down (chokers, protruding side walks and median island). ( Figures 3 and 4)

v) Streetscape changes and visual cues (street trees and plants, displays and decorations). (Figure 3.)

Residential streets

Residential areas constitute the largest and the most important land use in cities, and as much as 80 per cent of the total trips within the urban region have either origin or destination there. Moreover residential streets account for about 75 per cent of the entire urban road system. According to the standards of the Indian Roads Congress, the minimum width of the residential street should be 5.50 metres with 1.50 metre wide footpaths on either side. For congenial environmental conditions, speed on these roads should be restricted to 25 kmph and the peak hour traffic volume should not exceed 325 passenger car units. But in most of the residential streets in our cities, traffic conditions are far from satisfactory. Traffic volume carried is much higher and speed is also high. Due to uncontrolled access, non-destined traffic passes through these areas.

After a systematic study of road network, traffic and other conditions prevailing in various residential areas of the entire city, about 10 areas should be chosen for traffic calming measures to be introduced in these areas as a demonstration project for the city. The authorities concerned, local residents, voluntary organizations, industries and sponsoring agencies should be involved in planning, execution, monitoring and evaluation of these projects. The success of any such project depends to a great extent on the participation and cooperation of the local citizens.
Figures 1 – 4 show typical traffic calming measures for residential streets.

School zones

Though children constitute only a low percentage of total pedestrian traffic, they are involved in a large number of road accidents. At present, safety of children is not given adequate importance especially in the school zones, which face acute traffic problems, besides being places of frequent accidents. The principles of traffic calming should be applied extensively in school zones. It is suggested that six school zones be chosen in each city and improved with wide application of traffic engineering and traffic calming techniques as demonstration projects.

Various steps and measures that should be taken in connection with this project are listed below:

i) Diversion of through traffic, specially truck traffic from access road to school, by the introduction of appropriate traffic control and regulation measures.

ii) Introduction of one-way traffic regulation on the access road, atleast during the school opening and closure hours with a view to reducing traffic volume.

iii) Improvement of access road by providing wider side walks, raised pedestrian crossing close to the school gate, pedestrian refuge island in the middle of the pedestrian crossing, pedestrian operated push button traffic signal, school children drop-off bay on either side, speed humps on either end of the approach road, railing barriers to control the movement of pedestrians, reflective road signs and road markings. Figure 5 shows a typical example of traffic improvements in a school zone.

iv) School children to be trained as School Safety Patrol, and assigned the task of regulating the movement of children at the opening and closing time of the school.

v) Teachers to be trained in road safety, so that they can take overall control of safety of children.

Shopping areas and streets

In many cities, the city shopping centres do not generally have well planned road networks. In some of the cities, the city shopping centres take the form of a linear shopping street with side streets branching off at right angles. The main roads in these areas serve not only as the main shopping streets but also as a major through traffic route. These areas do not have sufficient on-street and off-street parking facilities, and these inadequacies adversely affect the efficiency of the area. The main problem is that these areas carry heavy volume of both pedestrian and vehicular traffic, and as the facilities provided for pedestrians are far from satisfactory, pedestrians face difficulties and also accident risk. More over the environment in which they move is awfully poor.

Prohibit entry of vehicles...

One of the ways of tackling these problems is to prohibit the entry of vehicles into these areas, and convert them into pedestrian precincts or malls. Such plans should be prepared area-wide keeping in view the overall convenience of the people. While the interests of business and motoring community should be considered, it should not be a hurdle in the introduction of such schemes, since these will improve the environment and quality of life in these areas. A modification to such a system can be done by altering the road system in such a way that through traffic will not be allowed to pass through these areas, and at the same time the vehicles are allowed to penetrate up to a particular depth. In the modified system, a part of the road is, however, closed for vehicular traffic.

Figure 6 shows the conceptual plan of traffic calming of a shopping street. The early examples of successful introduction of this concept are the central business sector of Chandigarh and the Connaught Place area of New Delhi. Pondy Bazaar in Chennai, Brigade Road in Bangalore and such areas in other cities may be taken up on priority basis for the introduction of such a plan. Depending on the local traffic and other conditions, this concept plan may be suitably modified for each location. In the case of Pondy Bazaar in Chennai, this road will be provided with a wide and raised pedestrian crossing at the middle of the stretch, as shown in the concept plan. The carriageway will be divided into two parts by a median island. The vehicles will be allowed to enter the southern part of the carriageway from either end of the road and park the vehicles. However, they will not be allowed to drive across the raised pedestrian crossing. This road being the main bus route, buses may be allowed to move on the northern part of the carriageway in both the directions with a speed limit of 25 kmph. The buses have to move slowly, as they have to drive over the raised pedestrian crossing. It is suggested that this scheme may be introduced in these areas gradually starting on Sundays, when the shops would be open. Then the scheme can be slowly extended to other days and other areas.

Recreational and other areas

Such a concept can also be introduced in the recreational areas so as to save them from the ills of motorisation and ensure better environment for the visitors to the area.

Figure 7 shows the conceptual plan for a recreational area with an abutting road having perpendicular access roads. This plan will ensure full depth of penetration, reduce speed, increase parking spaces, ensure pedestrian safety and improve the environment of the area. Such a scheme can be introduced in Elliots Beach area in Chennai with minor modifications in the road system.

In places like Marina Beach in Chennai, traffic calming scheme as shown in Figure 7 with suitable modifications can be implemented from 4.00 p.m. to 10.00 p.m. on Sundays and public holidays. For the convenience of the public, buses should be allowed to use the eastern part of the carriageway for both directions of movement, and operate with a speed limit of 25 kmph. The western part of the carriageway should be used by other vehicles in one-way direction as shown in the figure. Temporary barriers have to be kept in the middle of the carriageway to separate buses from other vehicles, but other vehicles will be provided access to the service road. Temporary islands have to be formed at appropriate places for channelisation of traffic. Traffic movement on the service road should also be suitably modified, so that traffic will move in segments, but not right through. All these measures will help to change the environment of the area and also benefit the common man.

Traffic calming measures should also be introduced in a phased manner in places of worship, hospital areas and other such areas.

Conclusions

With the rapid growth of motor vehicles and increasing number of trips, there has been a phenomenal growth in traffic on urban roads, resulting in acute traffic congestion, large number of accidents and considerable environmental degradation. For saving cities from the ill-effects of motorization, traffic calming measures should be extensively introduced. These measures will ensure that streets are valuable and safe public space to be shared equally by all users. Traffic calming will reduce the volume and speed of traffic, while encouraging pedestrians, young children and old people to share the street. Such schemes along with cityscape changes and visual cues will go a long way in improving the quality of life in the cities. The concept of traffic calming can be expanded to include “citywide traffic reduction” and “even changes in land use – transport system.”

With the keen participation of voluntary organizations and financial support of industries and firms, it is hoped these demonstration projects can be successfully implemented. The keenness of governments to improve the environment and awareness of the public to the need for improving the quality of life would help to tackle the challenges, which the society is facing as a result of rapid motorization.