An advanced dInSAR technique of Persistent Scatter Interferometry (PSI) is the method of choice for long term monitoring of the study sites. First the radar scenes covering one research area will be put in a stack coregistered with a very high accuracy. Pixels with a stable signal of both phase and amplitude over time will be selected as persistent scatterers (PS). Multi-step iteration of the stack will reduce atmospheric disturbances while reconstructing the phase signal of the PS, thus allowing deducing the motion of the single pixels relative to a reference point. The resulting data can be compared / completed with data from ground water level gauges or land surveying networks.