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Researchers said manure digesters – systems capturing methane from manure – can cut pollution but they come with risks.

New data indicated the systems can rupture and when they do, the damage can negate their environmental benefits. Digesters seal manure ponds and capture the gas they produce, which is then converted to methane for energy use.

Alyssa Valdez, a climate scientist and doctoral candidate at the University of California-Riverside and the study's author, explained the problem.

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"We can almost think of it like a balloon," Valdez outlined. "It does a great job of capturing all of that methane, but when it pops or when it leaks, you might create more methane than you accounted for."

The U.S. government has touted the systems as a good way to reduce emissions but the Department of Agriculture recently extended a pause on loans for anaerobic digesters through the end of 2026 because of "persistent and escalating concerns." South Dakota has a number of manure digesters and agricultural biogas plants. Valdez's work is published in Environmental Research Letters.

The study found the overall effects of digesters are hard to measure because management practices on individual farms and from state to state vary widely. Valdez argued they require tight oversight and constant monitoring because of methane's potency.

"It's 80 times stronger than carbon dioxide," Valdez pointed out. "We don't want to create large emissions of it into our air, into our environment."

The study recommended aerial observation and on-the-ground measurements to ensure the digesters are working properly.