The most effective way to avoid flood damage is to take precautionary measures to prevent damage from occurring in areas at risk of flooding. The Water Resources Act obliges the federal states to designate as floodplains within risk areas or assigned areas at least those areas in which a flood event is statistically to be expected once in 100 years and the areas used for flood relief and retention.
In Bavaria, there is a need to identify floodplains on all larger water bodies, the first and second order water bodies with a total length of 9,000 km, and especially in settlement areas on the smaller water bodies, the third order water bodies. These areas are determined by legal ordinance of the district administrative authority.
Technically, a digital terrain model, survey data and the evaluation of land use data and aerial photographs form the basis. This makes it possible to simulate a flood event, which statistically occurs once every 100 years, and to determine the associated inundation area.
In the form of site plans, the water management offices submit these results to the district administrative authorities for determination.
Various prohibitions apply in established floodplains. For example, no new construction areas may be designated in urban land-use plans or other statutes in accordance with the Building Code in designated floodplains. Exceptions are only possible under strict legal conditions.
If you select a location under "Localization" the contact details of the responsible authority and, if applicable, locally valid information will be displayed.