ANALYSIS OF URBAN TRAFFIC NOISE

Abstract

Noise is unwanted sound and people do not like noise especially in metropolitan environment. In metropolitan city, the predominant source of noise pollution is motor vehicle traffic which contribute about 55 % of total noise. Also in other urban areas and growing cities problem of noise pollution is alarming. Share of urban population is increasing rapidly and expected to be 35 % of total population upto 2001 A.D. In urban areas mostly dwelling units and a large number of people exposed to a noise level which is much higher than the level of human tolerance i.e. 45 dB(A). In Delhi the ambient noise level (Leq) has found to exceed the standard permissible value in almost all type of land use. The average equiN4lent sound loiel (Leq) in day time in silence zone, residential area, commercial area and industrial area has been found 81, 79, 81 and 78 dB(A) respectively whereas standard permisible value of Leq in day time as prescribed by Central Pollution Control Board, Delhi are 50, 55, 65 and 75 dB(A) in respective areas. Except in industrial area, road traffic is found to be major contributor of noise. In industrial area it is industrial machines which is equally responsible for higher noise level. Useful correlations has been found to exist between traffic parameters like traffic volume, average speed of traffic stream, distance from pavement edge etc. and noise parameters like equivalent sound level (Leq) in different types of land use area in Delhi. With the help of these co-rrelations, it is possible to predict the impact of traffic developments in terms of noise pollution in future and timely noise control strategies can provide relief to the Delhi city. In general trees, bushes in open space between road and buildings has been found as effective and eco-friendly noise barrier. The use of different type of materials in surface course can be tried to reduce the noise due to traffic. However, to control vehicular noise, engine modifications should be followed. Sometime noise abatement wall can be used to control higher noise level along road side.