Testing on-farm measures to reduce agricultural diffuse pollution
The Water Framework Directive (WFD) obliges member states to identify water bodies in poor ecological status, determine the causes of poor status, and to put in place cost-effective mitigation. These are challenging objectives; meeting them requires both new science and the synthesis and scaling up of existing knowledge at the field and farm scale to the catchment scale appropriate for WFD. Efforts to demonstrate the effectiveness of mitigation measures to prevent diffuse pollution have a long history in the UK. However, most work to date focuses on demonstrating the effectiveness of individual mitigation measures with few addressing the cumulative effect of combinations introduced into catchments.
The DTC project is addressing these challenges through work across the three consortia (Avon/Tamar, Eden and Wensum) which will be brought together to generate national guidance. Building on the characterisation and monitoring activities the three consortia have installed and are experimentally testing a range of diffuse pollution mitigation measures. These cover the
range of source minimisation, pathway interception and receptor protection activities which it is hypothesised will deliver ecosystem benefits. The effectiveness of the mitigation measures will be assessed through economic analysis and by undertaking a weight-of-evidence approach using multiple monitoring methods and source apportionment techniques. Findings will be developed by the research consortia into catchment plans for the DTCs and the insights gained will be integrated into national guidance and widely communicated.
Concreted trackway (right) and in-line sediment trap with flow gauging weir (above) to tackle surface water pathway in the Avon
Click here to see a presentation on the state of measures implementation and monitoring at the end of 2013 in the Wensum DTC catchment