Integrated catchment management for reducing pesticide levels in water: Engaging with stakeholders in East Anglia to tackle metaldehyde

In the agriculture intensive eastern region of England, plant protection products are widely applied to protect crops such as wheat and oilseed rape from pests and diseases, thus creating a risk of reaching nearby water courses through surface runoff. The EU Drinking Water Directive sets a stringent limit of 0.1 μg/l and 0.5 μg/l for individual and total pesticides respectively in treated potable water. However, peak metaldehyde levels have been persistently detected in raw water and reducing them to these limits has proven challenging and costly, in particular when using conventional treatment. In line with the EU Water Framework Directive, a more suitable approach and one adopted by the local water company, Anglian Water Services Ltd., would require moving towards mitigating pollution at source, preferably through participative action with multiple stakeholders in the agricultural industry. Initial findings demonstrate the potential of product substitution for reducing metaldehyde levels in surface waters. Reviewing Anglian Water's “Slug it Out” trial, we discuss key learnings derived from their experiences and make recommendations about the potential of the catchment approach to address the wider pesticide challenge