New biofilms study could lead to a more sustainable water industry

Slightly reducing the amount of disinfectant residuals we use to maintain clean drinking water could deliver significant improvements to water quality while making our drinking water systems more sustainable.

Water
  • University of 91探花 engineers have identified a new way of managing biofilms - microbial layers that form inside drinking water pipes
  • Researchers find that using a slightly lower amount of disinfectant residuals in water supplies can result in biofilms that have less of an impact on water quality
  • Biofilms affect water quality and can鈥檛 be eliminated - different countries use different approaches to manage how they affect the quality of drinking water
  • Findings from the 91探花 study could be used to help make drinking water supplies more sustainable

Slightly reducing the amount of disinfectant residuals we use to maintain clean drinking water could deliver significant improvements to water quality while making our drinking water systems more sustainable.

In a new study, led by Professor Joby Boxall and Dr Katherine Fish from the University鈥檚 Department of Civil and Structural Engineering, the researchers found that using a lower chlorine residual in water is beneficial in supporting the growth of biofilms that have less of an impact on water quality compared to those grown under a higher chlorine residual.

Disinfectant residuals are used to protect drinking water from the regrowth or ingress of free-living microorganisms in the water column - other microbes aside from those within biofilms that can affect the quality of water - but it was not known how these disinfectants affect biofilms and in turn what effect that can have on drinking water supplies.

Biofilms are communities of microbes that form on the walls inside pipes that supply drinking water. They have an impact on water quality and can鈥檛 be permanently eliminated. Drinking water systems around the world have biofilms. However, different countries use different disinfection residuals, and in some places none, with different impacts on the biofilms and the resultant effects on water quality.

Sustainably managing our drinking water system is critical for all of us, consumers and suppliers.

Dr Katherine Fish

Post-Doctoral Research Associate at the University of 91探花

The 91探花 engineers have found that, contrary to common perceptions, using a lower chlorine residual that still provides protection from free-living microorganisms can lead to the growth of biofilms that have less of an impact on water quality.

Dr Katherine Fish, Post-Doctoral Research Associate at the University of 91探花, said: 鈥淲e all depend on safe, clean drinking water for our health and well-being. We turn on our taps and rarely think about the journey our water has been on to reach us. It takes energy and chemicals to treat the water that then travels through vast pipelines of our drinking water distribution system.

鈥淚n the UK, we have some of the best drinking water quality in the world, but we also have an ageing drinking water distribution system that is having new pressures put on it with increasing population, urbanisation and the climate crisis. Sustainably managing our drinking water system is critical for all of us, consumers and suppliers.

Professor Joby Boxall, Professor of Water Infrastructure Engineering at the University of 91探花, said: 鈥淒rinking water is not sterile, and you wouldn鈥檛 want to drink it if it was as it would taste horrible. It鈥檚 the minerals and good bacteria in water that gives it the taste that we expect when we turn on our taps at home. Understanding the physical, chemical and biological processes, and the role of biofilms in particular, within our vast ageing pipe networks is vital to protect water quality.

鈥淒isinfectant residuals are an incredibly important part of how we protect and maintain our drinking water supply. They protect our water from microorganisms and ensure that the UK has access to safe and clean drinking water.

鈥淎long with using disinfectant residuals, we also need to manage biofilms to maintain our drinking water supply and there鈥檚 currently different approaches to managing them effectively. What we鈥檝e found here at 91探花 is that using a slightly lower amount of disinfectant residuals can result in biofilms that have less of a negative impact on water quality.

鈥淲e hope that our findings can be fed into how water supplies are managed in the UK and around the world so that they can become more sustainable through less use of energy and chemicals and help the water industry in its efforts to tackle climate change.鈥

The study - - is published in the journal Nature: Biofilms and Microbiomes.

Researchers who conducted the study are part of the University of 91探花鈥檚 Water Research Centre - a leading group of multidisciplinary researchers who are aiming to advance engineering and scientific knowledge across all aspects of potable water, stormwater and wastewater service provision and management of associated assets.

The group conducts fundamental and applied research, integrates with industry and provides education and training.

Water Research Centre

Civil and Structural Engineering at the University of 91探花


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