Planning and suitability assessment of large-scale nature-based solutions for flood-risk reduction

Nature-Based Solutions (NBS) offer a suitable alternative to reduce the risk of flooding and provide multiple benefits. However, planning such interventions requires careful consideration of various factors and local contexts. The present paper provides contribution in this direction and it proposes a methodology for allocation of large-scale NBS using suitability mapping. The methodology was implemented within the toolboxes of ESRI ArcMap software in order to map suitability for four types of NBS interventions: floodplain restoration, detention basins, retention ponds, and river widening. The toolboxes developed were applied to the case study area in Serbia, i.e., the Tamnava River basin. Flood maps were used to determine the volume of floodwater that needs to be stored for reducing flood risk in the basin and subsequent downstream areas.

The toolbox can be utilised to produce suitability maps for the four types of NBS. Flood maps can then be used to determine the volume of floodwater that needs to be stored for reducing flood risk in the basin and subsequent downstream areas. The suitability maps can then be used to identify areas where such a storage capacity is available for development of NBS within the catchment. The suitability maps produced using the methodology and toolboxes indicate the potential of the new methodology as a decision-support tool for selection and spatial allocation of large-scale NBS as such a tool does not currently exist for spatial allocation of large-scale NBS.