Intensive cultivation has resulted in an accumulation of nutrients and hazardous substances in the soil. These solutes represent a potential risk to the quality of both surface and groundwater. It is of vital interest to know the quantity and quality of seepage water which leaves the root zone, then enters the aquifer and finally the surface water system. To solve the problem we carried out trials at different scales to get information on how different land management methods influence the amount and quality of seepage water. We used direct lysimetry methods for measuring water and solute fluxes in soils. The combination of lysimeter studies with field experiments at different scales opens new possibilities for modelling and management of watersheds. The paper informs about advances in lysimeter techniques and technology and gives a practical application of this technique to measure the amount of dew. Based on an example the combination of lysimeter measuring results with the WebGIS based model STOFFBILANZ for calculating nutrient balances at catchment scale will be shown.