Research Looks at Water, Pipes in Closed Buildings
Since receiving $200,000 in funding from National Science Foundation’s Rapid Response Research (RAPID) program, researchers from Purdue University have launched a study into the impact of the pandemic shutdown on buildings.
More specifically, the team is looking at how water left sitting in the pipes of those buildings are changing in quality, in addition to stagnant water found in long-term hospital cloures, which have recently reopened to accommodate potential COVID-19 patients.
The Research
“We don’t design buildings to be shut down for months. This study focuses on the consequences and could help building owners make sure that their buildings are safe and operational when occupants return,” said Andrew Whelton, a Purdue associate professor of civil engineering and environmental and ecological engineering.
Whelton and other Purdue researchers are joined by experts, scientists and engineers from Virginia Tech, Legionella Risk Management Inc., Arizona State University, the University of Memphis, the University of Iowa, Northeastern University and Polytechnique Montréal in Canada.
Since launching the study, the team has reportedly began drafting recommendations for buildings owners based on implications from other studies. Their paper, “Consideration for Large Building Water Quality after Extended Stagnation,” is currently pending publication.
In continuing research, the team aims to provide advice for public health officials, building owners and water utilities on how they can safely recommission buildings with low or no occupancy due to COVID-19 pandemic.
After learning that the city of Detroit was working to restore water shut offs in the area, the team also worked with the American Water Works Association to publish a set of building recommission guidelines and pandemic response guidance for the area.
“We’re not going to have all the science done at the end of this study. But part of what we’re trying to do is put energy toward helping others develop guidelines so that they can at least go in and start recovering their buildings,” Whelton said.
Previously, Whelton and his team conducted water quality studies on school buildings closed for the summer and a variety of large office buildings. While they confirmed that water quality does change over time, they also looked at bringing in new water with disinfectant. Papers on the study are forthcoming.
“With normal building use throughout a district, even small amounts of water use would help draw disinfectant residual into a building. In the COVID-19 era, many low-use buildings in one area could affect the disinfectant residual in the water mains,” said Caitlin Proctor, a Lillian Gilbreth Postdoctoral Fellow at Purdue.
“As we come back to work after social distancing, even complete building flushing might not be successful in drawing in fresh water.”
During the field study, researchers collected samples from sinks and water fountains from buildings where they tracked temperature, oxygen and heavy metals, in addition to how microbial communities in pipes change over time and a pathogen called Legionella pnuemophila, which is known to cause a bacterial form of pneumonia.
“When you use water, you’re bringing in chlorine, nitrogen, phosphorus and a small amount of carbon. Bacteria sitting on the walls of pipes store up those nutrients for later use. But with months-long stagnation, there isn’t going to be any oxygen, new nitrogen or phosphorus,” Proctor said.
“So the bacteria that can compete under normal delivery of nutrients might not be able to compete anymore. For example, bacteria that do really well when there’s no oxygen might outcompete those that need oxygen.
Although, because not all bacterial growth is pathogenic, in addition to the number of bacteria, the team will also be looking at different types. In the lab, the team reports that it will be watching for chemical and microbiological changes in water stagnation found in water softeners and water heaters as well.
The American Society of Plumbing Engineers and the International Association of Plumbing and Mechanical Officials are collaborating with Whelton’s team on this study.
The study also has received input from the National Environmental Health Association and guidance from the Association of State Drinking Water Administration and Association of State and Territorial Health Officials. The findings are intended to help guide efforts by the U.S. Environmental Protection Agency, the Centers for Disease Control and Prevention, and state and local government agencies.
