Impact of restrictions to tackle high pollution episodes in Madrid: Modal share change in commuting corridors

Resumen

With the increasing concern about environmental problems in metropolitan areas, policy-makers are establishing restrictions on private vehicles in city centers to mitigate air pollution levels. Like many other European cities, Madrid fails to fulfill repeatedly the legal limits on pollutant concentrations established by the European Commission. Accordingly, in order to comply with acceptable air quality levels, Madrid City Council passed a protocol to address high NO2 pollution episodes. This paper aims at gaining deeper insight into how emission abatement plans foster a more sustainable mobility in suburban trips. To that end, a discrete choice analysis is conducted to explore the influence of the different restriction stages on modal share in a commuting corridor. Based on traffic counts and transit entrances, two multinomial grouped logit models are calibrated. Moreover, differences across trip frequencies are studied in order to determine to what extent a modal shift from private vehicles to more environmentally-friendly modes of transport occurs. The paper concludes that modal choice in suburban trips is influenced by the mobility restrictions adopted. Nevertheless, this effect shows to be fairly limited in the case of the Madrid NO2 Protocol. Therefore, more severe measures should be implemented to achieve a greater modal shift towards more sustainable transport modes.