Flood protection - general information

Prerequisites

Documents required

Please note

1. Preventive measures
   • Self-precaution of the population: People in endangered areas are obliged to take appropriate measures to reduce damage, such as
   • Flood-adapted use of land,
   • Protective measures on buildings (e.g. watertight basement windows, backflow prevention devices),
   • Securing valuables in flood-prone areas
2. Planning measures
   • Designation of flood areas:
   • Maps depicting flood-prone areas and floodplains are created and made publicly available
   • Establishment of floodplains that take into account at least one statistical 100-year flood event
   • Preliminary securing of areas likely to be designated as floodplains
   • Flood protection plans:
   • Preparation and regular updating of flood protection plans
   • Consideration of transboundary river basin districts
3. Structural measures
   • Construction and adaptation of flood protection systems:
   • Construction and modification of flood protection structures, including dikes and dams
   • Approval requirement for significant changes to existing protective structures
   • Strengthening and raising facilities to adapt to changing flood conditions
   • Compliance with building codes in flood zones
     • Prohibition of the construction of new building areas without the consent of the water authority
     • Permit required for structural changes such as earth embankments or storage of materials that could impair flood runoff
     • Ban on new oil heating systems in flood areas
4. Nature-based measures
   • Preservation and recovery of retention areas:
   • Prohibition of erosion-promoting measures
   • Promoting the recovery of natural retention areas, such as floodplain landscapes
5. Information and warning systems
   • Public information:
     • Warning and reporting services for early warning of flood risks
     • Providing information on appropriate precautionary measures and rules of conduct
     • Identification of particularly vulnerable areas
6. Regulation of use
   • Approval requirements:
     • Changes to the earth's surface, the storage of materials or the planting of trees and shrubs in flood-prone areas require the approval of the water authority
     • Restrictions on agricultural and forestry use in retention areas
   • Change ban:
     • Blocking structural changes that could hinder flood protection measures during the planning approval process
   • Pre-emption right:
     • The city's right of first refusal for land needed for flood protection measures or adjacent to flood protection structures
7. Technical requirements
   • Precautions for substances hazardous to water:
     • Measures to prevent pollutants from entering water bodies during floods
     • Adaptation of wastewater disposal and water supply to flood events

Deadlines

no

Procedure

Please contact the responsible office for information about your specific questions or concerns.

For further information, see "Notes".

Processing time

The processing time may depend on the individual case.

Fees

no

Legal remedies

No legal remedy is provided.

Legal basis

§ 79 Water Resources Act (WHG)


https://www.gesetze-im-internet.de/whg_2009/__79.html




Part Six of the Hamburg Water Act (HWaG)


https://www.landesrecht-hamburg.de/bsha/document/jlr-WasGHA2005pG18