Compost toilets

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You may have noticed that in the centre of the Indian flag there is a spinning wheel. This came about because, at the time of India’s independence from Britain, when the flag was designed, Mahatma Gandhi believed that true national independence would only be achieved through Swadeshi, which roughly translates as self-sufficiency. He believed that India would only truly earn political independence when it achieved economic independence. In order to do this, he encouraged the millions of Indians to start spinning their own cloth again and to stop buying it from industrial fabric centres such as those in Lancashire in England. This culminated in bonfires of Lancashire cloth lighting up the land as a powerful symbolic act. Therefore, the spinning wheel became the symbol of true political independence.

If I were to create a flag for the planet, it would have a compost toilet on it. The flush toilet represents everything that is psychopathic about our current culture and mindset – we shit and piss into a life-giving liquid, spoiling it in the process, instead of using both of these potential resources (in different ways) to fertilise the soil which, in turn, makes the food that we eat more nutritious. Instead, we import polluting fertilisers from distant laboratories once we’ve finished polluting our waterways. Somehow we’ve managed to take a really beneficial resource for the soil and turn it into a major ecological problem.

I urge you to ditch your flush toilet and install a compost loo as a symbolic and, dare I say it, spiritual act. It’s a no-brainer for anyone who wants to simultaneously stop polluting their source of life, drastically reduce their water consumption, and obtain a high quality organic fertiliser for their soil free of charge. Every single one of us could do it immediately, no matter what our circumstances. There are many models to choose from, but as human shit guru Joseph Jenkins points out, and Nicky Scott describes below, the simplest version is actually the best, looks much the same as a ‘normal’ toilet, and can be incorporated into any home.

If you want to collect some of your urine separately to this, but can’t pee in your back garden for various reasons, I’d recommend making a simple urinal (possibly in your garden shed if you have one) that channels your liquid gold (aka pee) into a bucket of some sort, which ideally you would dilute using greywater you’ve harvested from your sink, bath tub or from rainwater harvesting (a water:urine ratio of 5:1 is accepted as good). If we all captured our urine, either by compost toilet or urinal, it would save us flushing 18 million gallons of useful fertiliser into our waterbodies each and every day in Britain alone(148) (not to mention the hundreds of millions of litres of water used to flush it ‘away’). Instead of being a major pollutant, it would provide us with an easy and organic way of supplying our plants with a large percentage of their needs for nitrogen and potassium, meaning no more costly (ecologically and economically) imported and industrialised fertiliser into the bargain. If you can’t build a urinal, just pee in a bucket and transport it to wherever it is most useful.

Taking responsibility for our own excreta can seem like dirty work to modern humans, below us even. Yet doing so is an act of humility,(149) a spiritual act, one of respect and honour and gratitude, and all it takes is a change in our perspective. If we can’t even be bothered to, quite literally, sort our own shit out, then let us stop paying lip-service to caring for the planet, for our actions are much more revealing than our words. This is the very least we can do.

Nicky Scott, author of How to Make and Use Compost: The Ultimate Guide(150)

Being a ‘no-dig’ gardener, I can never seem to get enough compost. When I was young – a few months ago now – I had a Saturday job with a remarkable man called Dick Kitto,(151) a composting pioneer and author who collected all kinds of organic matter from around Totnes and mixed it with spent mushroom compost to make huge, steaming heaps of nutritious, free and organic fertiliser. It was he who convinced me of the importance of composting, and suggested that I go to the Henry Doubleday Research Association, HDRA (now Garden Organic), where I was once a ‘student’ in the early 80s. Lawrence Hills, its founder, was passionate about not breaking the cycles of fertility, and he showed me how crucial it was to follow the simple principle of returning organic matter back to the soil. So many farmers and growers today ‘mine’ the nutrients of the soil, taking away from the bank balance of fertility without thinking to replenish it with compostable materials; instead choosing to import synthetic nutrients for the quick, short-term fix. He exhorted us to collect materials from wherever we could – autumn leaves, wasteland weeds, the trimmings from the fruit and vegetable market, belly button fluff, skipped food from bins, hair from the barbers; basically, whatever we could find. It is only when you start looking for it that you realise how many free sources of compostable material there are out there to gather in. Doing so is absolutely crucial for anyone who aspires to live in a fully localised, non-monetary economy.

We had compost toilets on one of our sites, in Braintree, and it felt really good not using up precious drinking water to flush and transport my bodily wastes away. Flush toilets are, upon thinking about it, a bizarre concept. But it wasn’t until I read Joseph Jenkins’ excellent book The Humanure Handbook: A Guide to Composting Human Manure(152) that I fully understood how ridiculously simple it is to set up a composting system that could incorporate what we normally flush out of sight and mind. Indoor composting toilets can potentially be expensive and take up lots of space (the other option involves constructing a special structure outside). So instead, we had the downstairs toilet removed and in its place a simple box was made with a hinged lid and a wooden toilet seat. It now consists of one large bucket (you can obtain five gallon containers from almost any food business, and they will be more than happy to off-load as many as you want onto you) under the toilet seat and another beside the box, full of ‘soak’ materials (such as sawdust, soil, compost, paper, cardboard, autumn leaves) that we use to cover the deposits. When the bucket needs emptying it is taken to the compost heap and covered, layered with other compostable materials. Admittedly, there is more to the art than that, depending on your situation, and I would strongly recommend reading Jenkins’ book if you are at all interested (The Humanure Handbook is also free online(153)).

Composting is easy: it’s just water and air
After years of learning, experimentation and experience, I have finally distilled the essence of the composting system down to 2 things that you need to balance: water and air. You also need warmth, but unless you get a mixture of materials which contain enough water and allow airflow, then your composting will not be a satisfying experience.

I couldn’t possibly tell you how many people get hung up with dealing with grass cuttings (which, in my view, should simply be left on the lawn in order to maintain its fertility). Many people tend to dump all the grass cuttings from the lawn in a pile, which inevitably heats up quickly and goes smelly and sludgy, generating methane in the process. This isn’t any good for anyone. Instead, if these fresh and moist grass cuttings (along with fruit and vegetable peel, tops and tails and any soft sappy weeds) were layered or mixed (50/50 is good) with materials which allow airflow and others which absorb moisture (like shreddings, twigs, sawdust, prunings, cardboard and paper), a very useful compost heap would be created. The bigger you make your heap the more likely you are to generate and maintain high temperatures.

The best time to start a hot composting system is in midsummer, when there is no shortage of compostable materials around. My approach is to scoop the top layer off a current bin, dig out the bottom finished layers for use in the garden, before relaying the bin. I start this new bin with a coarse layer of dry, structural materials. On top of that I layer some soft greens, before adding the top of the old heap I just dug out, plus any weeds I’ve managed to gather. Always remember that you want to mix wet with dry, soft with hard, and if possible old with new. Balance is key.

Following these simple guidelines, you will see temperatures shoot up day by day. I tried an experiment with the ubiquitous ‘dalek’ bin your local council probably promotes, and recorded an initial ambient temperature of 20ºC. The temperature went up 10º every day until it peaked at just over 50ºC. In an insulated or larger bin it would have probably gone up even more. The level of compost in the bin, not coincidentally, dropped pretty dramatically over the same few days. This is the first really active stage of composting, and is driven primarily by bacteria and other micro-organisms. The more heat that is generated, the quicker the pile turns to useful compost. As it eventually cools, it goes into a longer maturation stage which can last months or a year. This is when the worms move in to finish off the job and transform it into the most amazing, life-giving substance.

Worms always come into compost discussions, and I found there to be a bit of a mythology surrounding them. It’s true that they are amazing creatures, but they really only work as I’ve described above, moving in as the heap cools and the materials are partially broken down; only then can they eat the soft parts.

If you want more worms for your compost (which you ought to), I’d recommend building yourself a wormery.(154) Wormeries are worm farms, a sealed container of some sort where you breed worms for your compost and, ultimately, your garden. Wormeries are perfect for dealing with small amounts of cooked food which, due to its ability to attract rats, can otherwise be tricky in small domestic composting systems. Word of caution: because worms hang around waiting for the materials inside to fester long enough for them to eat, it is important to add only a little food waste at a time to a wormery, otherwise they tend to be rather airless and smelly, and become too hot for the worms. Therefore, try not to think of a wormery as a bin, and instead a farm for little things. Get it right, and your compost and land will thank you for it, especially if you plan on using a no-dig system where the worms do the work (willingly, I should add), instead of you.