Measuring congestion in European cities: A focus on Brussels, Seville and Krakow

Congestion is a major issue for cities and often a determining factor of connectivity within urban areas and intra-city interactions. It is a repercussion of the massive adoption of cars as the main transport mode and an externality related to the nature of cities as it represents the negative aspect of agglomeration, the major driving force of growth in cites. We analyse the causes and impacts of congestion in order to be able to identify viable solutions against it. For this purpose, traffic needs to be studied at fine spatial and temporal resolution levels. We measure congestion at the level of Functional Urban Area considering the full transport network in order to estimate travel times between a large set of origins-destinations as determined by a high resolution population grid (size: 500mx500m). The impact of congestion is measured with the help of the relevant TomTom indicators that provide very detailed information on the variation of speed during the day at road link level. Road traffic also affects accessibility. We measure accessibility using different operationalisations, with and without congestion, for all the populated grid cells in the functional urban areas of Brussels, Seville and Krakow. By analysing urban areas at such a fine spatial level we manage to capture the impacts of congestion in detail. This study is the first step towards the assessment and comparison of traffic in all European cities.