5.1 Data on floods and floodplains

please provide general comments on section 5.1 here

At first glance, many data on floods and flooding are available throughout Europe, especially on the flood hazard. Water levels, discharges, flooded areas are better known and more easily comparable than the impacts of flooding. A hydrological analysis of interdepence and correlation of floods in adjacent groups of river basins will support the incorporation of the EU dimension in the estimates and impacts of floods. The catchment approach has proved useful but has its limitations when larger-scale processes become important, as is most obvious for climate change (Merz, et al., 2014).

Quantitative information on the impacts of flooding, being it fatalities, affected people or (direct) economic damages is much more difficult to have available on a European scale. Not to speak about impacts on cultural heritage or the environment, where the reporting for the PFRA (EU 2007, Art. 4) showed large gaps across Europe. Further development of the database on past floods (EFID), filling gaps and enhancing homogeneity of data by additional guidance on definitions and reporting, will promote the use and increase usability of the data.

Data can also be generated by computer modelling. Modelling exercises for Europe (Ciscar, et al., 2014; Dankers, et al., 2008; Rojas, et al., 2013) have the advantage of a more homogeneous methodology used across Europe to increase the comparability of results compared to natural map inventories, but lack in information on remaining and former floodplains, actual flood protection standards and on the actual technical state of flood protection infrastructure. This level of detail is needed when monitoring and evaluating the status, impact and effectiveness of adaptation efforts (EC 2013b). Research into the underlying mechanisms of flooding (e.g. advective versus convective precipitation, snowmelt versus rain), to improve future projections of flood frequencies, timing and depths and thus be helpful in estimating the effects of flooding on the environmental quality remains recommended (Merz, et al., 2014). Comparing this information with information on damages and impacts from floods contributes to our knowledge on adaptation and the effectiveness of NWRM measures. Where the data on European level aim at showing an overview picture, based on more or less homogeneous data, this hotspot analysis is not there to compete with detailed mapping on national level, being the one needed for detailed catchment scale assessments and the implementation of measures.

The reporting by the EU Member States on past floods, as well as the voluntary exercise organised by EEA ([1]) has resulted in a valuable database at EU level and detailed information at member state and basin level, available for the public (link to final version of EFID database). There’s a learning process related to the implementation of the FD and some elements in the reporting need further clarification in the next reporting cycle, but there definitely is a concerted action and more consistent and detailed outcomes can be expected in future. The next round of reporting will benefit from additional guidelines to further harmonise the approaches across the EU. Based on the draft FRMPs (WRc 2015), a preliminary conclusion is that the international coordination requires additional efforts.