Let's Talk Trash - Humanure

LTT - August 2022 - Humanure

    After writing about making kitchen/garden compost and peecycling in the past two Let’s Talk Trash articles, it now makes sense to turn to the other organic “waste” product we unavoidably generate - human excrement- also known as humanure. 

    On one of my early trips to Lasqueti, I was tested for island suitability when the boy I was visiting took me along to empty his poo bucket into a compost bin. Having never lived without a flush toilet, this demonstration blew my mind (I might have a gagged a little when the bucket poured into the pile). What a revelation! People can literally deal with their own shit! I was amazed, impressed and willing to join the ranks of bucket poo-ers. 

    Human excrement has long played a vital role in agriculture. Once referred to as “night soil”, it was collected in order to return to the fields in raw form. This method came with problems as human feces can contain pathogens and has the potential to spread disease. When sewage systems were developed to deal with the dangerous aspects of human excrement, the age-old nutrient cycle was broken. Instead of nutrients moving from garden to mouth and then back to soil, the pee/poo part of the cycle was classified as “waste” and removed. Chemical fertilizers were then invented to fill the nutrient gap. 

    Since the adoption of sewage systems and flush toilets in the developed world (most of the world’s population doesn’t have access to flush toilets) agricultural land has been depleted of useful nutrients while precious, clean, drinking water (especially in a time of climate change driven drought) has been the means to divert it. Flush toilets might seem clean and convenient to people accustomed to their use but they contribute to water pollution and degraded soil quality. More and more people, all over the world, are waking up to the fact that we are wasting our “waste”.

    In 1994, Joseph Jenkins self published the cult classic “The Humanure Handbook”, now in its fourth edition, and began convincing people that poo is a valuable resource. He coined the word humanure to describe this composted material and advocated for moving away from sewage and septic systems and toward composting toilets. Whether the composting toilet is a fancy commercial one or a funky outhouse with a bucket under the seat, his method can be summarized as follows: 

-Use sawdust to bury your poo. Sawdust provides carbon and this balances the nitrogen in the feces. A good carbon-nitrogen balance is needed for all composting. The sawdust also keeps bad smells in and keeps flies away. If your humanure pile is smelly, add more composting material, such as straw.    

-Do not separate urine and feces, as the urine provides moisture the microorganisms need.

-In addition to adding the “toilet” collection to the compost heap, throw on chunky materials like straw. This traps air pockets in the compost heap, avoids compaction and aids the process.

-Optionally, skewer the compost heap with sticks or pipes to provide more aeration. As the pile grows you can make a depression in the centre and add the bucket to the area where the biological activity is the greatest. This also promotes aeration. 

-Let this compost heap sit for a year before using on plants. If you are nervous of pathogens let it sit for a couple of years longer as pathogens can’t survive for an indefinite period of time without a human host. I personally apply my humanure to trees, bushes, flowers and berries.

-Choose a well drained site for your compost system. If it’s on boggy ground, close to a stream or on ground prone to flooding, it can contaminate ground water. Also, keep your compost system covered so rain and pests can’t get in. 

    If you haven’t tried it before, now you are ready to collect your household excrement so you can transform it into a rich brown material called humanure. The land will thank you for your deposits!