In order to maintain the water quality in the Netherlands, it is important to determine the various causes of nutrient pollution of surface water. For this purpose a tool will be developed, which can also be used for the evaluation of the Manure Act.
The aim of the Water Framework Directive is to improve the water quality. The surface water quality in relation to nutrients is determined by the emissions of point sources and difusse sources and the rentention processes (like denitricication and sedimentation) in the inland water. The contribution of emssions form point sources has decreased over the last decades end the relative contribution of the diffuse losses have increased. Therefore, integral evaluations of the land-surfacewater-system is necessary in order to determine the sources and pathways of diffuse nutrient losses, and evaluations of mitigation options are necessary. The goal is to set up a tool which can be used to determine the different sources of nutrient pollution of surface water and which is able to evaluate the effectiveness of mittigation options. In the first stage the model will be developed by integration information of the surface water system with the land system.