The University of Brighton and Southern Water collaborated on a research project to tackle the levels of chemical contaminants in the River Medway catchment to produce higher water quality standards.

Since 2000, the EU Water Framework Directive (WFD) has been fostering a new holistic approach to river basin management. The approach seeks to achieve good ecological and chemical status in water courses by managing a range of chemical contaminants, including pesticides. Metaldehyde, a synthetic aldehyde pesticide used globally in agriculture and particularly in slug pellets, is a particular problem because it is highly stable in water and is not effectively removed by drinking water treatment processes.

“Metaldehyde is an increasing concern for us and we needed a low-cost solution that we could bring in-house and use on an ongoing basis within the catchment team.” Rebecca Kennedy, Southern Water Research and Development Planner

Southern Water needed to develop capability in advanced catchment modelling, and through its relationship with the University of Brighton’s Green Growth Platform, developed a collaborative research project to investigate how computer modelling approaches could help to predict where and when water quality issues are most likely to arise. The project was led by Dr Sarah Purnell at the University of Brighton, and was funded by Southern Water using the River Medway catchment as a pilot.

An important aim of the project was knowledge transfer into the company. Rebecca Kennedy, Research and Development Planner at Southern Water said: “The model will help Southern Water to make important business decisions around the company’s investment in catchment management processes. It will help us determine where the risk hotspots are, and better target our mitigation measures through catchment-specific solutions, to address some of the biggest risks to our raw waters.”

Rebecca added that “The new modelling approach will give a visual view of what’s going on in the catchment and provide enhanced opportunities for engagement with our stakeholders including the National Farmers Union, local users and the Drinking Water Inspectorate.”

The project ran between 2016 and 2017 to develop a Soil and Water Assessment Tool for the River Medway Catchment using data from the UK Met office, Southern Water, the University of Brighton and Sutton and East Surrey Water, which is responsible for part of the catchment area.

The team produced hazard maps to show in-stream metaldehyde levels using simulated data from the model. These maps identified locations in the catchment at risk from the highest peaks in metaldehyde concentrations. Results suggested that up to 58% of in-stream metaldehyde could potentially be removed at specific points with effective management.

During the final six months of the project, university experts worked closely with the catchment team at Southern Water to establish a transferable protocol for future river basin mapping and predicting emerging pollutants. A series of knowledge transfer videos were produced to facilitate this long term.

This project supports the government’s clean growth challenge, one of the first four Grand Challenges announced as part of the Industrial Strategy Challenge Fund, and will provide the water sector with much needed resilience to future climate change.


This article first appeared in the 2018 State of the Relationship report, commissioned by Research England and compiled and published by NCUB.