Vehicular Pollution Assessment at Street Level Under Different Traffic Load

Abstract:

Traffic congestions on the roads of Nepal especially metropolis like Kathmandu have been increasing at an alarming rate increasing both particulates and GHGs. In the year 2006 alone the amount of particulates and green house gases (GHGs) from vehicles in Nepal were 642 tons and 10146 tons respectively. The pollutants cause air pollution and global warming. This study relates the emissions from vehicles in the present traffic jam and normal traffic flow conditions with special reference to the emission of particulate pollutants and CO2. Cline software was used to determine the pollution dispersion in three dimensions of the selected stretch of the road at various traffic flow situations ranging from extremely slow moving traffic to normal. The study showed the dispersion of pollutants under different traffic flow conditions and clearly indicated the increase of fuel consumption, CO2 emission and particulates with the increase of traffic jam on the studied stretch. The energy consumption in one 1km stretch with approximately 200cars during the extremely slow moving traffic condition (10 or less km/h) versus normal flowing (40km/h) traffic was calculated and found to be appreciable. The fuel consumption reduces to 30% to 50% thereby giving the less polluting tail pipe exhaust with proper traffic management. Appreciable difference was found in TSP as well as CO2 emission between the normal conditions and traffic jam with slow moving traffic. The study provides input to the reduction of particulate pollutants as well CO2 emission when the traffic flows in properly managed condition and suggests the traffic management ways in narrow Asian cities which can achieve substantial reduction in both pollutants and CO2 emissions and also enhances the quality of city life for drivers as well as pedestrians.

Keywords: Vehicular pollution, traffic management, GHGs