Published in the North Simcoe Community News on July 26, 2013.


The biogas ‘Amanda’ train runs between the Swedish cities of Linkoping and Vastervik. (Source: Wikipedia)

It is said that we all have gifts to offer the world. But are we flushing them down the drain? The time has come to talk about the mountains of manure that we, and our domesticated animals, produce.

“Wait!” you say, “That’s a problem, not an opportunity!”

It certainly is a problem. By centralizing our poop production in big cities and massive feedlots, we are re-distributing vast amounts of organic matter in the biosphere. Nutrients and water, in the form of feed, are drained from elsewhere, and injected into other ecosystems, along with host bacteria, as excrement. The end result: depletion in one ecosystem and pollution in another.

This was not what nature intended. Defecation is an effective way of recycling elements necessary for life. In particular, it is a fabulous source of nitrogen and phosphorus, two elements that are abundant in nature, but in forms unavailable to living systems. “Excrement is absolutely necessary for the resilient functioning of our planet,” says David Waltner-Toews, Veterinarian, Professor Emeritus at University of Guelph, and author of the informative and entertaining book, The Origin of Feces: What Excrement Tells Us About Evolution, Ecology and a Sustainable Society. (David was also the recipient of the inaugural award for contributions to ecosystem approaches to health from The International Association for Ecology and Health.)

Indeed, our mountains of manure have resulted in big problems. But they may also be the key to solving another difficult problem. We need a source of cheap, abundant, ecologically safe fuel to maintain our ever-expanding complex civilization of more than 7 billion people. In his book David Waltner-Toews outlines some wonderful projects throughout the world that address our often conflicting needs for human health, ecological sustainability, and economic wellbeing.

Biogas digesters are an exciting development, if you can focus on the output of the process, rather than what goes into it! They can be built to any size and for virtually any climate. Like Rasputin who spun straw into gold, these facilities turn human and animal waste into valuable assets: methane gas, high quality fertilizer and clean water.

The developing world was quick to take advantage of this adaptable process. China reportedly has 748 large and medium sized digesters that handle 20 million metric tons of human sewage annually. Rwanda has large-scale biogas plants in prisons and secondary schools. Many small bio-centers in densely populated slums of Nairobi, Kenya give people a private place to do their business. The methane gas produced is used to heat water for showers and is also supplied to kitchens in the surrounding area. In India, small-scale digestion facilities exist in over two million rural households, providing clean cooking energy.

Although many of the digesters have been built in the developing world, Europe and North America have projects too. For instance, in 2010, Britain launched a biogas plant powered by the sewage of 14 million customers. In North Carolina, a 9,000 head hog farm, in cooperation with Google Inc., built a biogas system that runs a computer centre. Now, Google and Apple are competing for the “fecal energy” produced by North Carolina’s gigantic hog farms. Sweden’s biogas train, the Amanda, was launched in 2005 and runs 120 km between two cities that provide the fuel (from a sewage plant on one end and from an abattoir on the other). Why are we threatening our ecosystems with fracking and sending bitumen through faulty pipelines when options like these exist?

Manure’s contributions are not limited to fertilizer and fuel. It has also been used to raise highly nutritious larvae to replace corn or soybeans in the feed of livestock, including farmed fish. Also, a California company, Micromidas, has developed a process for turning sewage into biodegradable plastic.

Whatever technological solutions we pursue to solve the problems of manure and to benefit from its useful properties, David Waltner-Toews urges us to use the One Health perspective: “the collaborative effort of multiple disciplines — working locally, nationally, and globally — to attain optimal health for people, animals and the environment”. We all live upstream from someone else, and our long-term wellbeing is dependent on a resilient, healthy environment. Flushing our waste away is no longer a good option. As the saying goes, “Waste not, want not!”