Manure (Yes, You Read That Right)

Manure is a billion-dollar industry. In North Carolina, for example, the hog industry generates 19,000 jobs and $10 billion a year in economic output, but with pork production struggling, hog farmers have been turning to manure to supplement their revenue. Collecting the waste from thousands of animals in million-gallon pits and creating massive ponds, called "lagoons," they sell it as manure to crop-producing farmers. The smell usually prevents neighbors from going outdoors. It can also cause health problems and environmental contamination.

But in places like Iowa, this is the smell of money. Manure producers need to be able to store it, and farmers need it to produce food. To keep up with these demands, we must create solutions to mitigate the risks. With a circular approach to address the problem, we can make the world a better place, not despite manure, but with it.

Concerns About Rising Manure Production

Rising prices for synthetic fertilizer have driven many farmers to switch to manure as a source of nitrogen and phosphorus — essential nutrients for plant growth, but in excess, dangerous to the environment. Massive manure lagoons release methane and other greenhouse gasses into the air. Long-term, excess manure nutrients build up and can cause soil imbalance. Manure also contains pathogens and antibiotics that farmers give to the animals to prevent disease in their densely populated living conditions.

With poor waste management practices, rainfall or irrigation events can cause manure lagoons to overflow. Waste runoff gets into nearby waterways or seeps into groundwater. Bacterial contamination from rising nitrate levels in groundwater can cause fish kills in surface waters. A 2018 hurricane caused over 50 manure lagoons in North Carolina to overflow, raising nitrogen levels in all surrounding waterways and depositing harmful bacteria that compromised drinking water and crops.

The waste runoff from rising manure and poultry litter production into waterways fuel the growth of harmful algal blooms that block sunlight from reaching underwater grasses and suffocate marine life. Algae growth in the Susquehanna River has resulted in low oxygen "dead zones." The Chesapeake Bay Foundation claims agricultural runoff, urban and suburban stormwater, and excess manure are responsible for more than 60% of the river's pollution.

Eventually, excess manure nutrients or bacteria can end up in our drinking water, causing gastrointestinal illnesses and other diseases. Scientists have linked hog farm emissions, like ammonia and hydrogen sulfide, to symptoms of "increased stress, anxiety, fatigue, mucous membrane irritation, respiratory conditions, reduced lung function, and elevated blood pressure." Short-term, the smell can cause nausea, vomiting, and coughing; long-term, it can result in higher infant mortality, kidney disease, mortality from anemia, and tuberculosis. People living near these contaminated ecosystems face serious health risks.

Details We Have Yet To Figure Out

Legal restrictions make it hard for city and county officials to regulate manure-producing farms. Many state and federal laws protect livestock facilities from government intervention, so federal legislation like the Clean Water or Clean Air Acts have little influence over Concentrated Animal Feeding Operations (CAFOs). Red tape, loopholes, and small-town corruption keep enforceable regulations from ever taking place.

A Penn State research team proposed more sustainable uses of manure resources could make a big difference in the Susquehanna River's water quality and improve the health of the Chesapeake Bay. It requires transporting manure from the lower Susquehanna River basin, where livestock farms are more abundant, to the land higher up in the watershed where crops need fertilization. However, the high moisture content of fresh manure makes it heavy and with few systems or logistics currently in place, transporting it can be very expensive, even over short distances. Most farmers want a better solution, but with no cost-effective way to do that, they keep filling their lagoons with waste.

Circular Solutions Solve More Problems

With demand for manure high, rather than reducing production, we need circular solutions making use of excess waste profitably and eliminating more of the problems manure production can cause. Farmers and other stakeholders can start by learning about options that might work for them and potential routes for implementation.

Eliminating the smell could reduce health risks for nearby residents and potentially improve local economic activity, which is why Impact Fusion developed a feedstock from sugarcane waste to result in scentless manure. To reduce air and water contamination, some researchers suggest anaerobic digestion using methane emissions to generate biogas. Farmers can sell the collected energy while bacteria in the lagoons process the remaining waste into compost, reducing smell, air spray, and the chances of overflow during storms.

As technology advances, we can do more. Seatech creates biogas more efficiently using an Anaerobic Sequential Up-Flow Reactor (ASUR). EKOGEA uses prebiotic microbial enhancement to convert nutrients into forms less prone to leaching and runoff. ADAR Technologies (disclosure: ADAR is a client of my company, GSDFuel, and I am also ADAR's interim CEO) uses a kinetic energy process to dry, pulverize, and sanitize waste material, eliminating the production of methane, as well as the smell and bacteria. Dried-out waste is lighter, saving money on transportation. It also creates a nutrient-rich fertilizer, which farmers can use to generate new revenue streams.

While individual farmers may not have the resources to contract companies offering these circular solutions, they can petition local governments in livestock-heavy regions to fund these investments as a means to save their industry. They can participate in research and development programs like California's Dairy Digester Research and Development Program, or seek partnerships with environmental groups like the Nature Conservancy and American Farmland Trust, which help to implement sustainable practices in nutrient management and manure recycling.

This may be more information than you ever wanted to learn about manure, but acting on these details is a step in the right direction to keep our planet healthy and thriving. Lagoon runoff into any mainstream water supply should be a national concern: the damage crosses borders. By harnessing circular solutions, we can mitigate the risks and sustain a billion-dollar industry, leveraging manure as a catalyst for positive change.