Managing waste and odors from hog farm lagoons
Florence hit with a loud and clear message: Prepare for more frequent and severe storms. As flood waters recede, the damage is still unfolding and likely will take years to address, with cleanup expected to cost in the billions.
North Carolina’s hog farms rank high in terms of storm vulnerability. As we braced for Florence, hog farms and their waste lagoons were a major concern. It’s hard to deny that when rainfall measures in feet instead of inches, lagoons are at a disadvantage.
When lagoons overflow or fail, farmers face massive issues. Releases must be contained, structures repaired, and there’s no place to manage animal waste so farms can continue operating. The waste, once discharged, poses serious risks to neighboring communities, rivers and watersheds, with water contamination, sludge, and bacteria spreading downstream.
Such failures occurred after previous storms and predictably again after Florence. Since Florence made landfall, the Department of Environmental Quality tallied overtopping of 32 lagoons, structural damage to five, and risk of imminent overflow at 39.
The situation is dire, but not hopeless. Waste management structures can not only be repaired but improved, making farms more resilient and enhancing their overall environmental performance. At most farms, it begins by covering waste and capturing the biogas it generates.
Why do this? Rather than be left open to the elements, waste can be collected in covered anaerobic digesters that capture biogas, decrease odors, and reduce pathogens. Digesters safeguard the waste, containing it under flexible caps that prevent water from getting in and methane from getting out. Once collected, biogas can be refined and injected into natural gas pipelines. This yields economic benefits and starts to address environmental and health concerns, which also may help neighbors and farmers avoid the courtroom.
The investment is well worth it. Digesters help farms build their resiliency to storms and provide new income. They help communities, farms and the environment by reducing pathogens and odors, keeping waste out of floodwaters and reducing greenhouse gas emissions.
At the state level, North Carolina would save in clean-up costs, profit from a homegrown renewable energy resource, and create well-paying jobs. The American Jobs Project determined that an average of over 2,200 direct and indirect family-wage jobs could be created in North Carolina by expanding biogas equipment manufacturing. Most of these jobs would be generated in rural and eastern parts of the state where economic prosperity lags.
While biogas technology isn’t complex and the revenue from biogas sales and associated environmental credits bring returns that make installation worthwhile, the upfront capital to install them is often elusive and expensive for farmers. Thanks to Florence, farmers don’t have much money to spare. What’s more, putting biogas into the pipeline is not easy, thanks to restrictive injection standards and high injection costs.
But the storms aren’t stopping and North Carolina can’t afford for hog farms to maintain the status quo. The answer is a coordinated strategy that helps farmers improve waste management practices, and it starts with biogas. The state already has a swine waste requirement in its renewable energy portfolio standard, which means our utilities must source some of our electricity from hog waste. Duke University and other entities are ready and willing to buy biogas and have been working to create a market to drive development.
More, however, must be done. Connecting the dots between capturing methane in manure lagoons and injecting biogas into pipelines is still a challenge and requires coordination between multiple stakeholders. But these barriers are surmountable if North Carolina’s leaders are willing to tackle these issues head-on. The state could help improve hog farm resiliency by including limited revival of the renewable tax credit for biogas projects, backstopping loans so farmers can install anaerobic digesters, requiring existing state-regulated pipelines to treat and accept renewable natural gas under the same terms and conditions as conventional gas and make existing pipelines more accessible to biogas developers, and creating a market that rewards farmers who invest in technology that reduces greenhouse gases like methane.
The vulnerability of hog lagoons is not news. In Hurricane Floyd, six lagoons were damaged and 55 others flooded. We spent $1.5 billion cleaning up after Hurricane Matthew. Now we will have to spend billions more, some of which could have been avoided. Let’s heed Florence’s message by using limited cleanup dollars proactively to prepare farmers for future emergencies with a solution that benefits everyone now.
Tatjana Vujic is Director of Biogas Strategy at Duke University. Kate Ringness is Managing Director of the American Jobs Project