40 Role of Kolkata Metro in Increasing Mobility and Improving Ambient Air Quality DEBASISH KUNDU Research Scholar, Department of Geography and Disaster Management, Tripura Central University, Agartala ESHITA BORAL Assistant Professor, Department of Geography and Disaster Management, Tripura Central University, Agartala Abstract ‘Kolkata’ formerly known as ‘Calcutta’ is the biggest business and administrative center of eastern India and state capital of West Bengal. Compared to other metro cities of India, Kolkata is notable for its lack of adequate surface road space. This, and the growing vehicular population leads to traffic congestion, reducing vehicle mobility and moreover increasing vehicle emission. To improve the transportation scenario of Kolkata, the metro railway service was created in the Kolkata Municipal Corporation (KMC) area in October 1984. This paper attempts to observe the role of the metro in improving passenger mobility and enhancing ambient air quality by reducing transport oriented air pollution in the city. For this purpose 15 major arterial roads in the KMC area have been selected. These roads are parallel to the existing north-south metro route and connect the northern and southern parts of KMC with the central part of the area. Traffic composition and the traffic flow scenario of the selected roads have been examined. The study shows that the Kolkata metro railway being an eco-friendly mode of public mass transit, performs its role in improving passenger mobility and reducing transport oriented emissions up to a significant level. Keywords– Congestion Cost, Emission, Urban Mobility, Public Transport, Rapid Transit System, Eco-Friendly Transport. Introduction Kolkata is one of the biggest metropolitan city located in the eastern part of India and administrative capital of state of West Bengal. The city expanded in the north-south direction along the left banks of River Hooghly, with the Sunderbans on its south and salt water basin on the east (Comprehensive Mobility Plan of KMA, 2008). Major roads were also developed in the north- south direction connecting the northern and southern parts of Kolkata with its Central Business District (CBD), that is, the Barabazar area. During the last few decades the city has witnessed