Motorways, Sprawl, and the (Un)Sustainable Economy The study provides a review of the main causes and consequences of urban sprawl and analyses empirically some of the economic and environmental external costs of sprawl for Portugal and its mains metropolitan areas.

Urban sprawl is usually addressed with a negative connotation due to its negative impacts on land uptake and contribution to a greater dependence on the automobile, which subsequently affects the environment as more fuel is consumed and more greenhouse gas emissions are emitted. There is also international evidence that investments in motorways have promoted urban expansion models akin to urban sprawl, particularly low density and dispersed suburbanization patterns. Portugal has one of the densest motorway networks in the EU and experienced a relatively late process of urbanization compared to other European countries. We study the relationship between motorways, urban sprawl and its impacts on travel mobility patterns and fuel consumption for Portugal over the period from 1991 to 2011. The results show that both motorways and urban sprawl have played a role in the shift in travel mobility towards greater automobile dependency and greater fuel consumption, which limit the country’s ability to meet the climate change targets set out in the national strategy for carbon neutrality by 2050.