SAWA - Strategic Alliance for integrated Water Management Actions


Which river basin management measures can reduce flooding dangers and improve the ecological status? In the SAWA-Project, the HCU Hamburg investigated this question regarding the catchment of the River Wandse, a small urban stream in Hamburg, Germany.

After an analysis of flooding dangers and ecological deficits the following measures were identified as synergetic measures to achieve the goals of both the Flood Directive (2007/60/EG) and the Water Framework Directive (2000/60/ EG) in the River Wandse catchment:
- Water retention through the use of sustainable urban drainage (infiltration measures),
- the retardation of water discharge through the creation of secondary floodplains, and
- the optimisation of existing retention basins.

These measures were investigated with respect to the extent to which they are suitable for implementation in the study area. Their expected effectiveness for the reduction of peak run-off during severe floods (>= HQ200) was estimated with simple and comprehensible methods.

The results show, that these synergetic measures can activate a considerable potential to retain flood water in the area of investigation. The effort for their implementation is considered acceptable if the implementation can go along with the renewal of urban infrastructure.

22 institutions from 5 countries in the North Sea Region formed the “Strategic Alliance for integrated Water management Actions” and developed strategies to implement the Flood Directive. Lead Partner of this Interreg IVB Project was the Ministry of Urban Development and Environment Hamburg (Agency for Roads, Bridges and Waters). The project began in late 2008 and ended March 2012.

The HCU Hamburg final report “Retentionspotentiale im Siedlungsbestand - Synergetische Maßnahmen zwischen WRRL und HwRMRL” (Potentials for Flood Retention in Existing Settlements - WFD-FD Synergetic Measures) holds all results. The report is written in German and contains a summary in English language:

- Summary (pdf, 111 KB)

- Final Report „Retentionspotentiale im Siedlungsbestand“ (pdf low resolution, approx. 7 MB)

- Final Report „Retentionspotentiale im Siedlungsbestand“ (pdf print quality, approx. 22 MB)

Project Lead

Prof. Dr. Wolfgang Dickhaut

E-mail: wolfgang.dickhaut(at)

Phone: +49 (0)40/42827-5095

Project Team

Scientific Assistance:

Tobias Ernst

Student Assistance:

Jan Dawidzinski, Cornelia Helmcke, Christian Ickler, Janina Stölting, Jeannette Thamm