UK wastewater plants struggle with climate change and rising population

Wastewater facilities play a vital role producing clean water, removing nutrients, generating renewable energy, and extracting other valuable bio-based materials from wastewaters.

While these systems have been engineered to withstand varying environmental factors to an extent, the study finds they are increasingly being put under extreme stress.

Using instrument data from operational monitoring systems provided by Southern Water and Thames Water, it found dynamic stressors, including higher rainfall intensity and extended dry periods, could be linked to pollution events.

The researchers said that the best way to avoid contamination, is to gain a better understanding of how events that stress the water network manifest, in order to give water companies an extended reaction time to events and try to reducing the impact on infrastructure.

Timothy Holloway, lead author of the paper, said: “Improving asset and infrastructure resilience is a significant challenge for the water industry as operational disruptions caused by stressors become more common and difficult to predict.

“As we face significant political, social and environmental uncertainty, water companies and government agencies are forced to manage complex and dynamic changes in resilience to events outside of their control.

“If we continue on the same path, it is extremely likely that we will experience more severe pollution events due to new and rapidly emerging stressors on wastewater systems. This could result in inland flooding, flood and storm damage in coastal areas, and damages to infrastructure.”

The study proposes using data from wastewater facilities to help mitigate further disruption in future.

Dr Gong Yang, process growth lead water quality at Southern Water, said his firm had been using effluent monitoring systems for the last two decades.

“This research puts forward a new tool to capitalise the advance of digital and sensing technologies,” he added.

“It aims to enable the operator to implement the best strategies in operating a sewer network or a treatment works based on live data so that the customers and environment are better protected from adverse impact of external environment such as climate change.”

Dr Ben Martin, lead research scientist at Thames Water, added: “We are now better able to cope with disruptions, predict and take proactive measures before asset failures, and create autonomous systems that ultimately improve the quality of water supplied to our natural environment.”

Last month, an environmental charity called for an “immediate end” to the discharge of raw sewage into the rivers of the New Forest National Park from various nearby wastewater treatment plants.