Conceptual models for the WFD : a case study on groundwater quantity for a groundwater body in The Netherlands

For which aspects of the Water Framework Directive (WFD) and the Groundwater Directive (GWD) do we need conceptual models and in what level of detail? How should conceptual models be managed to ensure subsequent improvement? To answer these questions a case study was conducted in the Netherlands, focusing on the quantitative status of one groundwater body. The experiences of this study will be used to give support to the national working group on groundwater in the Netherlands on how to proceed with the implementation of conceptual models.