Water depths for HQ100 in protected areas

Water depths for HQ100 in protected areas are areas behind flood protection facilities (e.g. dikes). The protection systems here are geared towards a 100-year flood (HQ100). In rare cases, the protected areas behind it can also be flooded with an HQ100 – for example, if a dike breaks because it no longer withstands water pressure or if the groundwater level behind the dike increases in the event of a long-lasting flood. The colour gradation in protected areas is intended to show which water depths can occur in such a case. It should be noted that in reality, depending on where a protective device fails (e.g. a dike breaks), water depths can also be set that deviate from the representation.