Providing natural flood management (NFM) interventions with a quantified impact on flood risk
Project summary: This project will allow a more strategic approach to be taken to NFM work and provide information that will help target areas that have the greatest impact on reducing flood risk. It will focus on different intervention types in the Upper Rother and River Hipper sub-catchments. These include leaky dams, tree planting, and offline storage ponds and different soil management techniques such as changes in tillage practices to reduce compaction.
Data provided by this project will also provide a directory of evidence to be used by NFM practitioners to help them decide which interventions are best placed for these particular catchments within the Upper Rother .There is an increasing need to quantify the impacts of NFM, including flood risk and the multiple other benefits provided, to determine, for example, payment bands in ‘Payment for Outcomes schemes’.
SD-TOPMODEL will be used during this project which is a hydrological model capable of modelling flow through a catchment and can be modified to represent different interventions. It has the ability to integrate soil management techniques, as the flow of water within the model can interpret different types of flow including overland and sub-surface. Soil management is a vital aspect of NFM, and offers many benefits, including flood management, as well as more efficient crop growth, water quality improvements and carbon storage. These benefits could help increase uptake by land managers.
Different scenarios will be prioritised and tested, for example, tree planting and soil management (including soil drainage improvement through introduction of organic material, reduced grazing stock in fields, reducing compaction from vehicles and reducing access for livestock to the riparian zone). This will allow the impacts of different intervention to be quantified allowing them to be prioritised as part of a strategic vision for the catchment. These could be, for example, how many interventions are needed to produce a 5% reduction in flood risk? Where are the interventions best placed for the biggest impacts?
SD-TOPMODEL has been used to address these problems in another iCASP project that investigated the impact of land use management on flooding in the Upper Calder valley.
It is also likely to benefit the landowner’s business and therefore may have a higher uptake. Working with key partners in the region (including the Don Catchment Rivers Trust NFM steering board – Environment Agency, Derbyshire County Council, North East Derbyshire District Council, Chesterfield Borough Council);
This project is a follow on project to the Don Hidden Heritage Secret Streams iCASP project, which brought together open access data to map the best sites for interventions by creating hotspot (risk) and opportunity maps. In that project, interventions were chosen which would help slow the flow, decrease diffuse pollution and increase landscape connectivity.
Project team: Don Catchment Rivers Trust (DCRT), University of Leeds, University of York
Duration: April 2021 – October 2022
Outputs: A directory of evidence to be used by NFM practitioners