Flow and transport processes in the transition area between the unsaturated and the saturated zone can influence the quality and properties of the groundwater. Special hydraulic properties have to be considered throughout the entire transition zone, which is a physically and bio-chemically highly active reaction chamber. Using the available measuring techniques, the present processes cannot be fully comprehended or, on the other hand, require significant effort. Thus, the influence of the transition zone is often neglected (Ronen and Sorek, The Unsaturated Zone-A Neglected Component of Nature. Water Quality Division, Israel Water Commision, Tel-Aviv, 2005). Utilizing laboratory experiments and numerical simulations, an innovative concept for a depth-specific measuring technique was evaluated. Results show that with some modifications of the actual design, the device is capable of sampling the entire transition zone between the unsaturated and the saturated zone, including the capillary fringe, with high temporal and spatial resolution.