River restoration: not only for the sake of nature but also for saving money while addressing flood risk. A decision‐making framework applied to the Chiese River (Po basin, Italy)

One of the key ideas of river restoration is that restoring rivers to a more natural status is desirable not only for pure environmental reasons but also to combat flood and geomorphic risk. This paper investigates whether this can be true even in a Mediterranean context, quite different from that of Northern Europe where European river restoration was born. Specifically, we evaluate whether the savings obtained from not implementing new protection works and from maintenance costs not spent – because of elimination of several existing works – exceed the likely increment of flooding and hydromorphological risk. Different conceptual approaches to the decision problem of flood control are synthesised within an integrated, three-level, evaluation framework. The proposed evaluation framework is applied to a case study on the Chiese River (Po River basin, Italy). Results for this case study are presented. Finally, findings, limitations and potential for application are discussed, concluding that river restoration offers a viable pathway for improving the river environment while not incurring additional economic costs associated with classic flood risk management.