Hidden within most water pipes are microorganisms that grow and produce a sticky, protective layer that helps them attach to the surface of the pipe. Over time, this develops into a microbial community that can erode pipe systems and foster harmful pathogens.
To combat this problem, Professor Woo Hyoung Lee of the Department of Civil, Environmental and Construction Engineering will investigate the critical challenges affecting drinking water infrastructure. With the aid of a team of researchers from the University of Florida, Lee will explore the interactions of biofilms, pipe materials, disinfectants and corrosion-control additives to mitigate corrosion and improve public health outcomes in the future. The project is supported by a $300,000 grant from the U.S. National Science Foundation.
Lee says researchers don’t fully understand how conditions such as disinfectant concentration, pH, dissolved oxygen and other chemical species change across a biofilm at microscopic scales, how these changes influence corrosion and metal release over time.
“Our project aims to understand the microscale interactions among biofilms, disinfectants, corrosion-control additives, and pipe materials that govern corrosion, metal release, and disinfectant stability in drinking water distribution systems.” Lee says. “Ultimately, we hope to connect what is happening at the microscopic pipe surface to changes that utilities observe at the larger distribution-system scale.”
As water travels through miles of distribution pipes that are laden with biofilms, Lee says its chemistry can change continuously. To maintain water quality, utilities rely on disinfectants such as chlorine and chloramine and corrosion-control strategies such as orthophosphate addition. However, these management approaches can alter microbial activity, water chemistry, and pipe-surface conditions, potentially affecting corrosion and metal release.
“Understanding these interactions is important because actions taken to address one challenge, such as microbial control or corrosion prevention, may also affect other chemical and biological processes within the distribution system,” Lee says.
Lee and his team will use specialized microelectrodes to measure chemical gradients within biofilms and at pipe surfaces, providing a level of detail that is not possible with conventional water-quality monitoring. The team will complement these measurements with advanced imaging techniques to characterize biofilm structure and growth, as well as data-driven and machine-learning approaches to integrate chemical, biological and materials data. Together, these tools will help reveal how biofilms influence disinfectant decay, corrosion, metal release and water quality throughout drinking water distribution systems.
The findings could help utilities make more informed decisions regarding disinfection strategies, corrosion-control practices and distribution-system operation.
“This research could help utilities better understand how changes in disinfection or corrosion-control strategies may affect microbial growth, corrosion, and metal release,” Lee says. “Rather than addressing these challenges independently, our work seeks to show how they are interconnected. In the long term, this knowledge could help utilities optimize treatment strategies, maintain water quality throughout the distribution system, extend the service life of infrastructure, reduce operational and maintenance costs, and ultimately provide safer and more reliable drinking water to the public.”