Assessing the Health Impact of Local Traffic Policy Plans

Assessing the Health Impact of Local Traffic Policy Plans


H Nijland, Netherlands Environmental Assessment Agency, NL; J de Hartog, Institute for Risk Assessment, Utrecht, NL; E van Kempen, W Swart, RIVM, NL


This paper will present the results of the ex-ante health impact assessment of the municipal traffic policy plan of The Hague.


Local traffic policy plans are usually meant either to solve congestion problems or to meet (European) air quality standards. Improvement of health is hardly ever the objective of traffic policy plans, although the rationale of the air quality standards is, of course, the concern about human health. As health improvement is rarely an objective, the health impacts of traffic policy plans are usually not assessed. One of the objectives of the European 6th framework project INTARESE ( is to assess health risks due to traffic policies. The project aims to answer the following questions: are apt methodologies for health impact assessment available, what are the strengths and weaknesses of the methodologies and data, is a health impact assessment feasible, and does the outcome provide useful insights for policymakers? This paper will present the results of one of the case studies carried out within this project, that is, the ex-ante health impact assessment of the municipal traffic policy plan of The Hague (due in 2010). As the assessment is due in April 2010, results in this abstract are preliminary.

In several streets in the city centre of The Hague, air quality standards are exceeded. By diverting motorised traffic around the city centre, the traffic policy plan aims to achieve compliance with the standards. As a result, the number of car journeys is expected to decrease slightly within the city centre as a whole, whereas the number journeys by bicycle and public transport is expected to rise by about 10 per cent.
Main health impacts from these changes in traffic flows are fourfold. Firstly, long-term exposure to air pollution changes for the residents. Secondly, more cycling implies more physical activity, which in general is beneficial to human health. Thirdly, a different traffic composition means different accident rates, as cyclists in general are more prone to (severe) accidents than car drivers. And fourthly, changing the traffic flow has its impact on noise exposure.

The study firstly shows that methodologies to calculate most health outcomes are available, but for some health endpoints exposure response functions are still non-existent. Uncertainty is particularly high in the assessment of health impacts from increased physical activity. For long-term exposure to air pollution, the assessment shows that health in the lower-income groups is expected to decline, whereas in higher income groups it is expected to improve. This environmental inequity goes directly against the official health policy of The Hague.
Secondly, the study shows that much effort is made to include car traffic and public transport in local-scale multi-modal traffic models. In traffic models, cycling is the ?Cinderella? of the transport modes. As, in the Netherlands, about a quarter of all trips is done by bicycle, scientific effort should be made to include cycling in the traffic models. Only in that way could traffic models truly handle multi-modality.
Thirdly, the overall health impact assessment, using DALYs and/or euros as indicators, still has to be performed in the coming months. Results will subsequently be presented to policymakers. The question of whether the study provides useful insights for them, should be addressed in the following period.


Association for European Transport