The National Science Foundation (Arlington, Virginia) and Water Research Foundation (Denver, Colorado) recently awarded more than $400,000 in grants to U.S. university researchers to help study methods to control lead pipe corrosion.
Adding orthophosphate to treated drinking water causes protective coatings to form inside, thereby preventing corrosion and controlling lead concentrations at very low levels. This makes it more difficult for harmful lead to leach out and contaminate drinking water—which happened in Flint, Michigan.
Daniel Giammar, an environmental engineering professor in the School of Engineering & Applied Science at Washington University in St. Louis (St. Louis, Missouri), and Jill Pasteris, a professor of earth and planetary sciences in the Arts and Sciences department, received
$229,000 to study the most effective ways of adding orthophosphate to reduce lead concentrations in tap water.
Meanwhile, Yandi Hu—an assistant professor at the University of Houston’s Department of Civil & Environmental Engineering (Houston, Texas)—
accepted a $188,531 grant to explore lead phosphate formations in water distribution lines, the school says.
“This is a wonderful project because of its direct link with real-world application,” Hu says.
But questions remain regarding the rate at which—and exactly how—the phosphate results in the growth and deposition of lead phosphate scales on aging pipes. This new research seeks to clarify the factors at work, while also determining the rate at which it can grow on pipe surfaces.
“It currently can take over a year after starting orthophosphate addition for lead concentrations to drop to acceptably low levels, and this project will provide new insights into the processes occurring at the pipe-water interface that can help identify strategies to more rapidly control lead concentrations,” Giammar says.