100-year flood

Under - century flood or flood of the century (even 100-year runoff, briefly called HQ100 ) is the level height or discharge quantity of a water body, which once reached or exceeded every 100 years on a statistical average.

Statistical predictive value

Since this is about a mean a flood of the century, however, may also appear more than once in a hundred years or centuries fail. On the basis of various statistical method also is not always full agreement on the chronology of various flood events. Due to the shortness of the records of flows created a large variance of the values ​​. This debate is also fueled by climate change, and thereby possibly increasing accumulations of extreme weather conditions.

Application

This value is relevant for measures of flood prevention and flood protection where it is used for dimensioning of flood- related facilities such as dams and bridges.

Colloquially refers to a flood of the century a severe flood disaster.