Around 70% of the drinking water produced by De Watergroep (a Belgian public water company) is extracted from 83 groundwater pumping sites. To control the risks that endanger the drinking water supply and for the groundwater extracted to be as pure as possible, a risk-based approach for the protection of the catchment areas is developed, as part of the water safety plans. The approach consists of three steps: first, the compilation of a site-specific source file, second, the performance of a risk analysis for every catchment area, and third, the development of a monitoring strategy and action plans. The general goals are to lower the level of purification and to enhance the sustainability of groundwater extraction. The listed benefits make it worthwhile to implement this approach, despite the uncertainties.