The Manure Problem and the False Promise of Biogas

When researchers from the Center for a Livable Future (CLF) presented at the 6th Annual Johns Hopkins Sustainability Symposium, manure emerged as a main theme in the discussion. As pointed out by Brent Kim, a faculty scientist at CLF, while a modest amount of manure can be valuable as a source of fertility, at industrialized livestock operations, it’s produced in such excess that it does far more harm than good. Allie Wainer, also a program officer, spoke about how manure digesters, which produce “biogas,” promise to solve the manure problem but fall short of that goal and in many cases worsen the harms of industrial animal agriculture. And Darriel Harris, also a faculty scientist, painted a bleak picture of life for the residents—usually in poor communities or communities of color—who live near manure digester operations and industrial livestock facilities.

Moderated by journalist and CLF senior research associate Tom Philpott, the three researchers made a case for their presentation, titled, “It’s getting worse: the human and planetary health consequences of industrial agriculture.”

“It’s likely that methane digesters cannot address what they promise,” said Allie Wainer.

In a best-case scenario, Wainer said, digesters could potentially reduce some of the problems of manure management, such as odors, while perpetuating or exacerbating others. Studies suggest, for example, that digesters may increase ammonia emissions and pose higher risks for soil water quality. Digesters may also introduce new problems, such as methane leaks, and the fact that biogas is in some cases burned, a process that releases volatile organic matter and particulate matter into the air. 

A more nuanced issue with digesters is that the biogas is often piped to facilities where it is processed for use as fuel or electricity, which means that new infrastructure needs to built, deepening our reliance on fossil fuel infrastructure. Yet another issue is that the financial incentives that come with digesters may encourage producers to keep even bigger herds. And of course, the more that digesters become business-as-usual, the more the industrial livestock production systems become entrenched.

Darriel Harris focused on the community consequences of industrial livestock production. He mentioned the flies and buzzards associated with the operations, as well as the contamination of well water. The industrial operations may result in irritated skin for residents, as well as having to endure nauseating smells. Many of them cannot afford to move.

“The waste will travel up to 2 miles in the air,” said Harris, speaking about manure opensprayed onto nearby fields. “It feels like it’s a drizzle when you’re near it.”

When residents suspect that well water is contaminated, they can call upon municipal government agencies to test it, but if it tests poorly, the agencies will shut down the water, leaving residents with nothing to use for bathing, flushing, and washing clothes. Often, residents will endure the contaminated water and drink bottled water.

Another issue he addressed is “flares.” The operators of the digester flare excess gas from the conditioning facility where the biomass is stored, burning it off. 

Brent Kim covered some of the other harms posed by industrial livestock production. He addressed the pollution created by animal waste and acknowledged the ways in which uses of antimicrobials in industrial livestock operations are “eroding the effectiveness of lifesaving medicines.”

Kim also noted that pigs have unique respiratory tracts that are susceptible to both avian and human strains of influenza, which make them, potentially, a mixing vessel where recombination of viruses can occur.

“This is why it’s a bad idea to raise tens of thousands of pigs in highly pathogenic conditions,” he said.