Development of a methodology for creation of flood protection concepts under consideration of climate change based on the example of the stream Windach

Investor: Bavarian Ministry of State of Environment, Health and Consumer protection
Project manager: Univ.-Prof. Dr.-Ing. Markus Disse (UniBwM)
Project assistance: Dipl.-Ing. Wolfgang Rieger (UniBwM)
Project duration: 2007 - 2010


The extreme flood events during the last years have shown that not only technical flood protection measures but also decentralized flood protection can contribute to integrated flood management. Using the example of the catchment area of Windach (Oberbayern) this research project should investigate, to what extend additional detention basins in the catchment area downriver of the Windachspeicher (reservoir) can damp flood waves effectively, to what extend measures of decentralized flood protection enable more reduction of the stream flow peak and how the anticipated climate change could intensify the flood conditions.
The project is divided in following individual operations:

1. Literature research:
As the first step the current status about decentralized flood protection is investigated and quantifying examples, especially from Bavaria, are illustrated. Furthermore current and realistic results from regions nearby in Germany, Austria and Switzerland are included.
The close cooperation with the responsible public authorities in the sectors of Environment, Agriculture and Forestry as well as with the water management office ensure a multidisciplinary procedure and a high actuality of the investigation.

2. Modelling of the actual state, future land use and climate changes, and intended renaturations:
Under use of the water balance model ASGi (WaSiM-ETH) and the hydro-dynamic-numerical model SOBEK the effects of land use changes, drainages and renaturations on flood routing are investigated. 
The influence of the anticipated climate change is used in the simulations to quantify spatially distributed the changed runoff forming under changing of climate conditions espacially for meso-scale catchments (change of growing season, cultivation of new crop plants, change of the forest structure).

3. Creation of a flood protection concept for Windach:
The terminal step should determine under consideration of the predicted climate change for flood annualities HQ5, HQ20, HQ100 and HQextreme the combined effect of technical flood protection measures, change of land use as well as renaturation of waters.
Due to the coaction of both models the influence of changed land use, decentralized detention basins and renaturation of waters to the flood routing is ensured.