Municipal wastewater treatment plants emit nearly double the amount of methane into the atmosphere than scientists previously believed, according to new research from Princeton University. And since methane warms the planet over 80 times more powerfully than carbon dioxide over 20 years, that could be a big problem.
“The waste sector is one of the largest anthropogenic sources of methane in the world,” said Mark Zondlo, professor of civil and environmental engineering and associated faculty at the Andlinger Center for Energy and the Environment. “As cities continue to urbanize and develop net-zero plans, they can’t ignore the liquid wastewater treatment sector.”
Zondlo led one of two new studies on the subject, both reported in papers published in Environmental Science & Technology. One study performed on-the-ground methane emissions measurements at 63 wastewater treatment plants in the United States; the other used machine learning methods to analyze published literature data from methane monitoring studies of various wastewater collection and treatment processes around the globe.
“Not many people have studied the methane emissions associated with wastewater infrastructure, even though we know that it’s a hotspot for methane production,” said Z. Jason Ren, who led the second study. Ren is a professor of civil and environmental engineering and the Andlinger Center for Energy and the Environment.
Read more at Princeton University, Engineering School
Image: Independent studies by Princeton researchers Cuihong Song and Daniel P. Moore concur that methane emissions from municipal wastewater in the U.S. are actually closer to double than formerly calculated. (Photo by Bumper DeJesus)