TRANSPORT GENERATED AIR POLLUTION ON NATIONAL HIGHWAYS IN HARIDWAR DISTRICT

Abstract

In a rapidly urbanising country like India, the transportation sector is growing very rapidly and the number of vehicles on the Indian roads is increasing at the rate of more than 7% per annum. During the period of 50 years after India's Independence from 1951 to 2001, the number of vehicles has increased from 3 lakhs to 430 lakhs, i.e. an increase of almost 143 times. This has lead to overcrowded roads and, in turn, a polluted environment. The transportation sector is the main contributor to the ever increasing air pollutant concentrations in most of the major metropolitan cities. This factor is also contributing immensely to the pollutant loads in smaller cities also. According to a study conducted by RITES, cars and two-wheelers contribute to approximately 11% and 78% of the total transport related air pollution and vehicles, in general are responsible for around 64% of the total air pollution load within an urban network. Hence, it becomes imperative that studies be conducted on this aspect and corrective measures be suggested and enforced to.counter the menace of Transport related air pollution. The use of models in the predictive analysis of transport generated air pollutants is a convenient way to predict the Pollutant concentrations. However, since most of such models are developed abroad, their feasibility in their application to Indian conditions needs to be thoroughly investigated before they are applied. Some of the popular models include the CALINE series and the HIWAY series. Indians too have developed some models and the most popular amongst them is the GFLSM model. In the present study, an effort has been made to study the air quality at seven locations in the Haridwar district in terms of concentrations of Carbon Monoxide(CO), Hydrocarbons(HC), Nitrogen Oxides(NO„), Sulphur Oxides(S0x), Suspended Particulate Matter(SPM) and the Respireable Suspended Particulate Matter(RSPM). The studies have been carried out during the normal traffic flow times and during the Ardh Kumbh Mela times, a religious festival observed at Haridwar and which attracts a very high number of devotees, which in turn results in high traffic inflows into the city. The pollutant concentrations have been related to various traffic parameters using linear regression analysis to achieve a better understanding of the observed data. Results of the linear regression show that while CO and HC are related to the number of petrol driven iii vehicles, NO and SO„ are related to the number of diesel driven vehicles. The SPM concentrations are related to the total vehicle volumes. The application of CALINE-4 model and the GFLSM model for the prediction of CO concentrations was done to assess the feasibility of application of these models. The results show that the GFLSM model performs much better than the CALINE-4 as it is developed in India and is better suited for the Indian conditions. The GFLSM model gives a better correlation between the Observed values and the Predicted values of CO MULTIPLE with the RZ (coefficient 0*ml-elation) value of 0.9525 as against the value of 0.9050 of the CALINE-4 Predicted values of CO. The significance tests have also been carried out to test the significance of the difference between the Observed values and Predicted values at 95% confidence level. For the GFLSM values, the significance tests (t-tests) show that the difference between the Observed and Predicted values is insignificant for all the seven locations while in the case of CALINE-4 model values, the difference is insignificant for five of the seven locations.