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Abstract for December 11, 2018 Webinar


Title:  Decontamination of Legionella in Home Plumbing Systems and Drinking Water Infrastructure Decontamination at EPA's Water Security Test Bed

Harmful bacteria such as Legionella pneumophila, which causes Legionnaires disease, can live in home plumbing systems when water is stagnant, temperatures are high and the amount of disinfectant (like chlorine) in the water decreases. These conditions help bacteria grow on the pipe walls and form layers of slime called biofilms. L. pneumophila can live in or stick to these biofilms. This webinar will cover the results of research into how to remove, or decontaminate, chemicals and bacteria that stick to the inside of the water pipes that make up home plumbing. The aim of this study is to determine how well everyday water disinfectants kill off L. pneumophila living on common plumbing surfaces. Results indicate sticking to biofilm, the disinfectant used, and the type of plumbing material affect the survival of L. pneumophila.

This webinar will also focus on home plumbing decontamination experiments at the EPA’s Water Security Test Bed (WSTB), which is a full-scale model of the large water distribution pipes that transport water around cities. The WSTB consists of 450 feet of 8-inch diameter cement-mortar lined ductile iron pipe with functioning fire hydrants. Connected to the 450 ft pipe is a 1-inch copper water service line that is the same as what would be installed under the yard of a homeowner’s house. This copper service line feeds a water meter, household plumbing pipes and appliances like a refrigerator, washing machine, dishwasher and hot water heater. Results will be presented about which contaminants can stick to home plumbing and appliances, and how to get rid of them with common techniques like flushing water taps, adding chlorine to the pipes and running the appliances with and without detergents. Contaminants include a non-harmful surrogate for the bacteria that causes Anthrax, Bakken crude oil and the firefighting foam that is used to fight very hot fires.

About the Speakers

DR. JEFFREY SZABO has a BS in Chemical Engineering and a MS and PhD in Environmental Engineering, all from the University of Cincinnati and is a registered Professional Engineer in Ohio. He has worked for the USEPA’s National Homeland Security Research Center for 14 years in the Water Infrastructure Protection Division. He conducts and manages water security research projects at EPA’s Test and Evaluation (T&E) facility and the Water Security Test Bed (WSTB) at the Idaho National Lab (INL). These projects include examining chemical, biological and radiological contaminant persistence on drinking water and waste water infrastructure and evaluation of decontamination and water treatment methods.

DR. HELEN Y. BUSE is a microbiologist within EPA's Office of Research and Development, National Homeland Security Research Center (NHSRC) in Cincinnati, Ohio. Since joining EPA in 2007, her research has focused on understanding microbial and chemical factors that promote the growth of Legionella pneumophila within drinking water systems. She is currently investigating the disinfection of L. pneumophila within premise plumbing biofilms using various treatment technologies. Helen has a Ph.D. in Microbiology and Immunology from the University of Michigan and a B.S. in Biological Sciences from Carnegie Mellon University.

See the webinar main page for further details.