How can we use a modelling approach to predict the movement of waterborne bacteria and viruses, especially in a notoriously tricky coastal location? This is the challenge a team from Bangor University is facing, along with colleagues from water and subsurface specialists Deltares, Istituto Superiroe di Sanità (ISS) and the University of Exeter.

The 55 km-long River Conwy (Afon Conwy) rises in the moors of Snowdonia, widening into the Conwy Estuary near Conwy itself before flowing into the Irish Sea. It’s a well-known beauty spot and tourism destination; however the river and its catchment (the surrounding area where rainwater collects) have a long history of microbiological pollution. With shellfisheries on the Conwy as well as recreational activities, the risk of impact on public health is high.

What are we doing?

The new modelling approach aims to determine how pathogens in the River Conwy, its coastal zone and its catchment are impacted by environmental stressors and climate change. To do this, the team is developing a modelling approach that will identify areas of high risk to human health from pathogen exposure.

Delft3D is a coastal circulation model, which shows the dispersal of pathogens in response to tidal flows, storms and input from rivers. The model will be combined with live data, such as weather, tidal movement, wastewater discharge rates, livestock movement and health board data (for example, a local outbreak of norovirus) to create a real-time risk alert system.

Who will use this? The alert system will benefit so many stakeholders, from the shellfish industry to the Welsh Tourist Board. It will identify poor water quality in high-risk areas such as beaches, marinas, water sports centres and the fisheries.

Timeline

Here’s what the team is doing:

Why is this important?

The River Conwy experiences regular discharges from wastewater treatment plants and farms. This leads to outbreaks of infections, both directly from the water and via the shellfish industry. Finding a solution that protects locals, visitors and shellfish consumers is essential.

Recent advances in mathematical modelling and cloud computing let us create more effective prediction models. Combining the flow of both coastal and catchment water in one model gives a clearer picture of the movement of pathogens from sources to sea.

The innovative addition of live data means that we can develop a real-time risk alert system, that will benefit everyone with a connection to the river. We’re also linking to the latest climate predictions to enable more accurate forecasting. The resulting tool will help stakeholders actively manage pathogen risks.

For further reading, this paper provides more background on bacteria in the River Conwy:
Climate and land-use change impact on faecal indicator bacteria in a temperate maritime catchment (the River Conwy, Wales) – ScienceDirect