Humanure: Sewage Composting

I have written extensively here and elsewhere about the critical need to move away from wasteful sewage remediation strategies and towards more sustainable reclamation strategies. One of the main value propositions of this change is the conservation of water. For rural areas where there is abundant water, there are different value propositions.

I visited a radically sustainable communal farm in Tennessee called The Garden and documented one exciting solution to this problem.

Humanure is the idea of simply composting sewage without trying to do biogas capture or water reclamation. The garden built a kind of hovering toilet which moves between several concrete bays. The sewage simply falls into the bay and collects. They add a scoop of wood chips instead of flushing the toilet with fresh water. Over time the pile grows and then they move the toilet to an empty bay.

Composting Toilet

 

The old bays are left to compost for several years before being used as a valuable soil additive.

Here is the same structure from the back, showing the bay and the sewage…

 

Composting Toilet Bay

 

Advantages

One of the biggest dangers of the way we currently grow food is the way corporate-scale agriculture amends soil. There are two main problems with the normal strategy. First they are always growing the same crops over and over. This is because we subsidize specific crops federally. There is just no reason to be growing corn and rice in America. We don’t even eat them. We export them, but these crops are almost exclusively all that is being grown. Monoculture also destroys the soil by extracting the same nutrients year after year, and adding nothing to the soil, like rotating crops would.

Why? Because they are subsidized as part of a disastrous government program to get farmers to grow specific arbitrary crops instead of growing things people actually need and want. This led to widespread consolidation of farmland into a small number of large corporations, and led to one of the greatest existential threats of climate change; nitrogen loading.

Nitrogen loading arose as an attempt to solve one of the problems of corporate-scale monoculture. Because they are growing the same terrible crops on the same land, year after year, the soil dies and loses the nutrients those crops need. So they solve this problem by tilling deeper and deeper to find soil with some life in it and then dumping enormous amounts of ammonia onto that soil. This kills the soil again but it adds nitrogen from the ammonia and allows them to continue growing these same crops over and over as long as they can reach some trace of life next time they till the soil.

The problem is that this is a terrible strategy; the arable land is being destroyed deeper and deeper down every year, plus an enormous amount of chemicals are being dumped onto the land every year to try to hold this catastrophic system together. Because of this, it is now extremely likely that we will have another dust bowl. This is a phenomena that occurs when the soil dies, leaving dust that blows around and covers other land, killing the plants there. It quickly spreads and destroys whole regions, and it’s already happened in America once in the past. We didn’t learn the lessons.

 

So What’s A Better Alternative?

Corporate-scale agriculture should be banned. Subsidized crops should be banned. We should give the land to the people who can then grow the food they need, trade with others, and practice sustainable permaculture on the land; improving the land rather than destroying it.

Properly managed land does not need additives, pesticides, and other chemicals. Remember that the ecosystems we live in survived just fine for hundreds of millions of years without us. Human activity is the problem, but changes to our behavior are also the solution. Instead of dumping our sewage into the rivers, we should be processing it and using it as a soil additive. This would leave the land stronger and healthier rather than leaving it dead and barren.

This should be our fundamental goal; to improve the world around us rather than stripping it for resources and leaving it dead and barren.