In floodplains of large rivers, more than eighty percent of the potentially inundated areas are developed for agricultural use and settlement purposes by diking and cultivation measures. The fertile soils of the polders represent ten percent of the agricultural lands in Germany. At its time, this agrarian potential justified the high societal input for diking, flood diversion, and drainage. The 80 000 hm2 large Oderbruch polder is deemed an example of prospering agrarian regions since 300 years ago and today it is part of the national cultural heritage. Numerous levee breaches and flood damages brought about increased efforts on levee construction and drainage. With growing technical facilities, drainage and the utilization of remaining wetland sites became the favoured target towards the development of highly productive man-made landscapes. The cost for flood control and drainage were state-borne for a long period.