Opportunity
The cost of treating raw water to remove these substances is high but catchment management solutions have the potential to reduce elevated pesticide and nitrate concentrations, and avoid the need for additional energy and carbon-intensive treatment.
Solution
For surface water, we developed a modelling approach to simulate catchment hydrology and pesticide transport processes in each surface water catchment supplying Anglian Water’s drinking water sources. Our approach takes a holistic view of the catchments, integrating hydrology, hydrogeology, water quality and agronomy.
For groundwater, we combined existing modelling packages with a bespoke model spreadsheet to simulate nitrate transport through the soil zone, and unsaturated and saturated zones, to the groundwater source. We used our models to calculate how long it takes nitrate to travel from agricultural fields to Anglian Water’s boreholes, and to identify the most effective way to target catchment management activities, allowing Anglian Water to carefully focus their resources to improve groundwater and surface water quality.
Outcome
Anglian Water has used our results to inform its catchment management strategy. Following our recommendations, it employed a team of dedicated catchment advisors who work with farmers to implement its successful ‘Slug It Out’ campaign, addressing the metaldehyde problem and raising awareness of pollution from agriculture. We are continuing to work with Anglian Water to develop the modelling tools for use in new, innovative projects.