We provide our hydraulic engineers with safety verifications and design flow discharges for flood control retention basins according to DIN 19700 and calculate design water levels for dams, dikes, and flood protection walls. We study the protective effect of polders, retention areas, and other protective structures and en-sure local drainage by means of hydraulic assessments. While doing so, we keep an eye on the effects on neighboring residents, people downstream, and the environment.