Diffuse Water Pollution from Agriculture (DWPA) is a significant pressure impacting protected sites. The ecological condition of the River Wye is deteriorating, in part due to DWPA. The intensification of agriculture in the form of Intensive Poultry Units (IPUs) and high levels of legacy phosphorus in the catchment’s soils have been receiving significant scrutiny.
Where site conservation water quality targets are being exceeded (this is the case for the River Lugg currently), it is necessary to understand the scale of interventions that are needed to achieve nutrient loadings (Phosphorus and Nitrogen) that would enable targets to be met and support protected site recovery.
Using Farmscoper v5 (a farm-scale decision support tool), a range of land management scenarios were modelled for the River Wye catchment to predict the nutrient reductions that could be achieved. Scenarios ranged from no measure implementation to maximum possible reduction achievable through measure implementation and also included land use change based on 30×30 targets. Catchment specific data was used in place of default values in Farmscoper v5, where possible. This included utilising soil P data (as presented in the RePHoKUs Project Report) and catchment specific livestock data.
The outputs from the modelled scenarios are presented in this report, with the findings being used to support decision making in the catchment on appropriate action to reduce DWPA, including contributing to the evidence base for the River Wye/ Lugg Diffuse Water Pollution Plan (DWPP).