Flooding protection measures are often expensive. A cost benefit analysis can help to prioritise flood protection measures. Within the SAWA project an approach for cost benefit analysis (CBA) of flooding protection was developed (find the description under case studies below). In the following, some aspects to consider making a CBA are shown and some difficulties are pointed out.
Compared with conventional flood protection measurements (e.g. retention basins) local decentral solutions (e.g urban drainage systems) can consist of different measures and therefore it is more complicated to keep track of all costs.
Some measures have a positive secondary effect on flood protection but are constructed mainly for other purposes (e.g. sustainable urban drainage systems). How should these costs be considered?