A global overview will be given of the water quality of the private-groundwaterwinnings in the Netherlands. Although the overview is far from complete, is becomes apparent that the water quality of most winnings does not satisfy the legally established requirements for drinking water. Especially, the high nitrate concentrations and the low pH-value, due to acidification (and related to this, the concentrations of aluminium) are the cause of the water not satisfying the requirements. Also three-dimensional groundwaterflow and matter transport will be modelled near an abstraction site. Concentration-courses are calculated for nitrate and atrazin, for two types of scenio's. In the first type, no reduction or prohibition measures will be taken. In the second type, these measures will be taken in 1995. It becomes apparent that after 15 years, these measures will have their full effect.