Development of Urban Traffic Noise Model for a Mid-Sized City: A Case Study of Kanpur

Abstract

Traffic noise is emerging as major challenge for cities in India. It affects human health in terms of annoyance and other major health problems. This study aims to develop a traffic noise model for mid-sized cities. Vehicle noise and spot speed of individual vehicles were studied to develop a reference energy mean emission level (REMEL) by using the sound level meter from a reference distance of 7.5 m from the centerline of a nearby lane under free flow condition. This urban traffic noise model is specific to different geographical regions and depends on vehicle categories and characteristics of in use vehicles. Subsequently, mid-block studies were conducted for measuring traffic noise L_eq (in dB(A)), average speed, and traffic volumes of different vehicle categories. To develop the traffic noise prediction model, physical condition of the road, carriageway width, width of the footpath, median size, number of lanes, and ground cover (hard or soft) need to be accounted for. A modified traffic noise prediction model has been developed using REMEL models and different adjustment factors. Subsequently, the correlation analysis was performed between predicted and observed L_eq (in dB(A)) to check the model fitness by correlation coefficient R² = 0.76 and mean absolute percentage error is ranged from 0.8 to 1.2% for the predicted and observed L_eq at all the selected sites of measurement periods for the Kanpur city. With this calibrated model, a noise map has been developed to identify noise hotspots during different time intervals within the city.