Sustainable Catchment-Wide Flood Management: A Review of the Terminology and Application of Sustainable Catchment Flood Management Techniques in the UK

Climate change has seen increased pressures put on the existing ageing flood mitigation infrastructure. As a result, over recent decades there has been a shift from traditional hard-engineered approaches to flooding to more sustainable methods that utilise nature-based processes in order to slow flow, store water and increase infiltration. Doing so has resulted in a range of different nomenclature for such techniques, particularly in the rural environment. This paper takes a critical review of such terms to draw parallels in the different approaches, with the aim of developing a more unified, consistent approach to flood management. Furthermore, links have been drawn with the urban environment, where Sustainable Drainage Systems (SuDS) are used as a sustainable approach to urban flooding. The findings from this review have identified a series of issues that result from the current UK approach of differentiating between urban and rural flood risk, with funding often given for Natural Flood Management (NFM) projects separately to SuDS, with little integrated thinking from source to sea. Hence, the review suggests (1) a greater consideration of scale, focusing on the catchment as a whole, is required to ensure a more holistic approach to flood management, under the phrase "sustainable catchment-wide flood management", to ensure that the focus shifts from NFM (rural) and SuDS (urban), to a more integrated catchment-wide approach; (2) the development of robust policy and regulatory framework, to ensure that such an approach is more widely adopted; (3) a greater consideration of the long-term costs is also required, with future research needed on the long-term maintenance costs of different methods; (4) the development of modelling approaches that can simulate flow at a range of spatial and temporal scales, to support stakeholders, such as local authorities, flood risk engineers and government agencies when considering flow not only in rural areas, but also to understand the impact beyond the immediate area around the scheme.