One may wonder what the desired outputs of resilience, efficiency and legitimacy mean for the strategies that one should implement. The criteria that are most directly applicable for determining an optimal set of strategies are the capacity to resist, the capacity to absorb and the resource efficiency. The first two capacities reflect that regions vulnerable to flooding will be more resilient if multiple flood risk management strategies are implemented simultaneously.
In several European countries, engineers and flood defence measures dominate the flood risk management domain. Although this often appears to be an effective and economically efficient strategy, other strategies could enrich and enhance flood risk management. By combining multiple flood risk management strategies, loss of lives and social, economic, environmental and cultural losses can be decreased and recovery or smart adaptation after a flood event can be enabled. In other words: if one strategy fails, another is still in place, creating a backup.
On the other hand, it may not be efficient to implement all flood risk management strategies simultaneously. It may for example be more efficient to invest money in flood defences than to invest money in flood proofing buildings. This depends strongly on the local physical situation, on past investments, and on the governance capacity to implement certain strategies.
For instance, in countries with a dominant focus on flood defence, (Belgium, France, Poland and the Netherlands), the presence of effective flood defence infrastructure is a necessity (‘must have’) and other strategies could be viewed as add-on strategies to reduce residual risks (‘nice to have’). A country like England with more of a balanced approach to strategies experiences more floods, but at the same time performs better in terms of response and recovery. And in France (and to a lesser extent Belgium) the recovery system is well developed. This contributes to resilience, but also to the risk that citizens and companies pay less attention to prevention and mitigation. That is to say citizens and companies trust that their losses, in case of a flood, will be compensated negating the need for prevention and mitigation.
An important finding from STAR-FLOOD is that having multiple strategies in place may cause fragmentation. Actors, policies, laws and other tools and instruments that link and align strategies are therefore essential.
As there is no ‘one size fits all solution’, evaluation of the pros and cons of each strategy and combination of strategies, for a specific country or region is recommended. This way, one can develop an approach that is tailored to local physical, socio-economic and institutional conditions.
In the next chapter (§3.4) we describe four steps that can be taken to analyse and improve flood risk governance in a specific area. The steps concern the strategies to employ, as well as governance aspects that ensure their implementation and instruments to bridge gaps between strategies and governance arrangements. Furthermore, in chapter 4 we present a number of concrete good practices for integrated planning. These examples may provide inspiration on how to select an optimal portfolio of strategies and measures.