Vehicular exhaust emissions under current and alternative future policy measures for megacity Delhi, India

This study analyses the impact of integrated mass rapid transit system (IMRTS) and other policy measures on air emissions from vehicular sources in Delhi region. The impacts have been studied for the passenger and goods vehicles separately. For this purpose three alternative scenarios for the passenger vehicles and two alternative scenarios for the goods vehicles have been analysed for the year 2021. The interventions include stringent source emission norms, modal shift resulting from introduction of effective public transport alternatives, speed regulation measures and hiking of parking fee of private vehicles. These scenarios have been compared to the base year 2007. An important finding that emerged from the study is that stringent fuel emission norms and introduction of alternative public transport systems alone may not result in the modal shift and hence reduction in exhaust emissions. It is actually a combination of these measures and management measures such as increased parking fee and regulated uniform speed of public transport that results in desired benefits. Further, the inclusion of goods vehicle demand during transport policy formulation can help in controlling air pollution in new urban centres in India and in major developing regions of the world.