The European Union Water Framework Directive (WFD) requires good chemical and ecological status for all European waters. Runoff from roads during the building and operating of roads will affect the European waters and might be a cause for water not to reach a good chemical and ecological status.

At this moment, it is unknown which and how certain organic micropollutants and microplastics are transferred from roads to water bodies, what environmental risks these substances might cause and by which concentrations these risks will occur and what the best way is to treat these micropollutants. Knowledge and available literature about particles, metals, road salt and nutrients in road run off is rather extensive, while literature and data about other potentially hazardous pollutants (in particular organic micropollutants and microplastics) is limited. However, increased knowledge about these substances is necessary to ensure that water bodies are protected against pollution.

This research project ‘Microproof’ focusses on the impact and possible reduction measures of organic micropollutants and microplastics.

Overall, the objective of this project is to provide scientific insights about risks and measures in a practical manner for road managers in order to preserve, protect and improve European water quality. The practical project objectives are:

• To provide insight in the main factors causing micropollutants from European roads enter the water bodies and to provide insight in which particles end up where and in what concentration.
• To show which micropollutants form the main reason for environmental concern, based on comparison of predicted environmental concentrations and predicted no-effect concentrations.
• To develop a decision support scheme which helps to select the optimal treatment measures to avoid contamination of surface waters under diverse conditions.