Sample image: ÖWGes Project Weiz, 2-3 storey residential building [Source: https://oewg.at/projekte/weiz-brentengasse]
Western Europe
Construction project on Schwanbergerstraße, Deutschlandsberg
Assignment location
Austria
Funding
ÖWGes non-profit housing construction company / ÖWGES Housing Construction
The non-profit housing association ÖWGES intended to develop plot 42/1 in the cadastral municipality of Hörbing (municipality of Deutschlandsberg). Due to the risk posed by the foreland runoff of the Laßnitz river in the event of a 30-year flood, an exemption under water law was required.
Key players and participants:
- Client: ÖWGES Gemeinnützige Wohnbaugesellschaft mbH
- Processing: HYDROPHIL GmbH
- Coordination: Official expert for hydraulic engineering, Southwest Styria District Construction Authority
- Planning partners: RZP ZT GmbH (transport), Kratzer & Partner ZT GmbH (geotechnics, HWS), Pilz Verkehrsplanung
- Involvement of local residents: Statements from resident Isabella Herk and utility companies
Geographical scope: Plot 42/1, Hörbing cadastral municipality, municipality of Deutschlandsberg, StyriaSize: approx. 2 ha
Sectoral context: Residential area with mixed use (apartments & commercial), close to state roads L618/L656 and public transport connections.
Main objectives:
- Ensuring that the property is approved for development under water law
- Integrating flood protection into an urban development concept
- Establishing clear hydraulic engineering constraints for a design competition
Expected results:
- Approval-ready concept for HQ30 and HQ100 exemption
- Multifunctional use of flood basins as infiltration areas
- Adaptation to future traffic developments (roundabout, sidewalks)
Technical services provided by HYDROPHIL GmbH:
Results and outputs:
- Action plan with HQ30/100 exemption
- Submission to WR authority on February 28, 2025, follow-up submission on September 19, 2025
Environmental measures:
- Definition of green strips as infiltration basins and multifunctional areas
Social aspects:
- Involvement of affected residents with consideration for existing drainage systems
- Balancing of usage interests, such as the municipality's roundabout and residential development
Health and safety:
- Flood safety through freeboard specifications: ≥65 cm above high water level
- Ensuring accessibility to pipeline systems
- Determination of building boundaries in coordination with road services (state road administration)
Flood safety HQ100; Image source: HYDROPHIL / Klaus Jerlich
Lawn hollow; Image source: ÖWAV Rule Sheet 45
Used for architectural competition; Image source: HYDROPHIL / Klaus Jerlich
