Hochwasserpeaks

Hochwasserpeaks, literally high-water peaks, denote the maximum water levels or peak discharges reached during flood events in rivers, lakes, and coastal areas. In hydrology, such peaks are extracted from hydrographs as the highest observed stage (level) or discharge (Q) during a flood.

Measurement: Gauging stations provide continuous records of water level and flow. The peak stage is the highest gauge height relative to a fixed reference (gauge zero). The peak discharge is the maximum Q, in cubic meters per second. The time of occurrence is also noted.

Applications: Hochwasserpeaks are used for flood risk assessment, the design of hydraulic structures, floodplain management, and emergency planning. They serve as input for hydrological models and for determining thresholds in flood insurance and disaster response.

Factors affecting peaks: Rainfall intensity and duration, catchment response, soil moisture, snowmelt, dam releases, and land use influence the magnitude and timing of peaks. Urbanization and changes in river morphology can increase peak discharges by reducing infiltration and increasing surface runoff. Climate variability and climate change may shift the frequency and size of Hochwasserpeaks.

Data and forecasting: Peaks are analyzed from historical records and used in extreme value analyses for design standards. Forecasting relies on rainfall-runoff models and real-time monitoring networks; ensemble forecasts help estimate the likely timing and magnitude of peak flow, aiding warnings and evacuation decisions.