The autopsy came back in April. It didn’t look good: contraband muscle-building steroids, cooking oil, nappies and a smattering of MDMA. Beyond these toxins and alien objects, the 130 tonne South Bank fatberg, the latest congealed, impacted mound of wet-wipes and clotted fat to be discovered in London’s sewers, was also found to contain potentially deadly antibiotic-resistant bacteria, alongside worrying levels of listeria, campylobacter and E. coli.
Undetected fatbergs lurking beneath our streets run the risk of raw sewage flooding into the open, and at present the battle to eliminate them costs the public £80 million a year. Our Victorian-era sewers are struggling so much that every year 40 billion tonnes of sewage is deliberately flushed into the Thames; as a result, Thames Water has been commissioned to build a £4.2 billion super sewer after the EU decreed the leeching of raw fecal matter into the Thames unacceptable.
The capital’s network of sewers evolved over the course of the 19th century to meet the challenges of the public health crisis that was pre-industrial life: cholera, typhoid, dysentery. But could there have been another way of doing things? A hardcore group of environmentalists thinks there is. Could we, by composting organic human outputs, find a way to manage our environment and ourselves that wasted less water, returned needed nutrients to the land, and avoided some of the problems that our overburdened, centralised sewage system is currently struggling to solve? Or, to put it more bluntly: can we make human shit useful?
Joseph Jenkins, author of the 1996 ecology bible The Humanure Handbook, began to compost his faeces and urine over forty years ago. He was, at the time, living without electricity and plumbing, trying to lead a simpler sort of life, and began to see the benefits of composting and reusing the nitrate and phosphate-rich solid, what so many consider waste, as fertiliser.
Studying for a masters in sustainable systems and the built environment in northern Pennsylvania – the first of such courses running in the US – he decided to turn his thesis into a book. In the US, The Humanure Handbook has now sold over 65,000 copies and is about to run into a fourth edition, and Jenkins’ spin-off compost toilet business, Lovable Loos, is still going strong.
It’s not correct to call faeces ‘human waste’, Jenkins says. “A compost toilet is a waste-free toilet system; there is no waste involved.” What comes out goes back in, to be reused as fertiliser on his land – Jenkins grows corn, onions, parsley, sweet peppers, hot peppers, broccoli, courgettes, winter squash, beetroots, blueberries, and raspberries. He has apple trees, peach trees, pear trees. He keeps chickens and he keeps ducks. "I have the whole nine yards going on here," he says.
But using faeces for good is not just a DIY project of the impassioned few. At festivals, in emergencies, and amid poor sanitation, human manure can be used to grow grub and mitigate disease. Shambala, a festival that takes place every year in Nottinghamshire, rather than using chemical loos, contracts Compoost Solutions to manage 300 compost toilets and uses the produce to fertilise crops at Gilcombe Farm in Somerset. "They smell less," says Graham MacVoy, site manager at Shambala. "They're not everyone's cup of tea but I think that it's a much better solution both for the environment and as an experience."
Composting is simple and cheap. You do your business in a container and you cover this with a heavy-ish material – a biofilter – like sawdust, which keeps the smell under control. Jenkins says oak sawdust is the “perfect biofilter – it doesn't matter how stinky something is, you cover it with that and you can't smell anything”. Other people use sugar cane residue, bagasse, or rice hulls. You can compost anything, he says – vomit and urine too. “My last bin had 29 dead animals in it” – racoons and possums he shot because they were killing his chickens and ducks. “I shot twenty racoons in a seven week period. It was like a plague,” Jenkins says.
This mixture is then decanted into a larger compost bin, with a covering that has a lot more volume like straw or hay. It’s imperative these bins are watertight and not in areas at risk of flooding. The difficulty, according to Nance Klehm, composting expert and founder of Social Ecologies, is making sure it gets to a sufficiently high temperature: faeces needs to be composted in a hot, “thermophylic” environment of between 41 and 122 degrees celsius to ensure pathogens die off. This sometimes involves adding fruit and vegetable leftovers to create a higher heat.
Klehm used to run an urban composting initiative in Chicago called the Humble Pile. Thirty per cent of our water bills, Klehm says, goes to toilets, and when there are natural disasters like hurricanes, the need to use water in a more conscientious way shows us that living in a low-water way ought to be a form of knowledge we hand down. We have, Klehm argues, been taught to fear what comes out of our bodies, be it blood, faeces or urine. While these things can be pathogenic, they are also “very mundane and are things we all contain – and it’s what connects us all as humans with biological processes. To them it’s ugly, and I think it’s fascinating,” she says.
But for Klehm and Jenkins, making human manure is not simply an ecological or environmental calling. It is intimately connected to wider political beliefs. Klehm talks of the benefits of this way of managing faeces in protest camps like Occupy, which crop up spontaneously in public spaces, where people need to stay clean without the high cost of bringing in chemical toilets. Compost loos were used at Standing Rock, she says, because “porta-potties were costing the tribe a lot of money”. For Jenkins, the very need for human manure came from a vow of poverty he had taken after seeing the atrocity of the Vietnam War, and wanting to keep his income under federally taxable levels. “It was just sick and insane and there was no way I was gonna contribute towards it,” he says.
Efforts to compost human faeces aren’t without their issues. “There's a very good reason we are not supposed to come into close contact with shit. That is quite simply because it can be a very good vehicle for lots of toxic and dangerous bacteria, viruses, eggs – ascaris eggs – parasites,” says Rose George, author of The Big Necessity, a global look at how we deal with human poo.
Open defecation continues to be a problem all over the world, and is strongly linked to rural poverty. Over the past 28 years, access to more hygienic sanitation has jumped from 54 to 68 per cent, and 2.3 billion people still don’t have access to basic sanitation, of whom 892 million have to defecate in the open.
“When I worked in Haiti, people were shitting in plastic bags and throwing them someplace. The plastic bags would degrade in the sun and then there would be a rain and then E coli would be dripping across the sidewalk,” says Klehm, who helped to set up dry toilet systems with different communities there, using sugar cane waste from a nearby rum factory. Bodies like the Bill and Melinda Gates Foundation have been funding efforts to redesign the toilet, removing germs while holding onto the good.
"There are two and a half billion people with no toilets,” Jenkins says. He has just returned from a month-long trip to Tanzania, Uganda and Kenya, which impressed on him the huge demand for this way of doing things. “They say to me that this is a revolution. And I'm trying to figure out how to deal with it. How do you provide toilets for millions of people? How do you teach millions of people how to do composting?”
Poorer countries, though, aren’t the only ones where sewage systems are flawed. “Defecating in drinking water is a kind of insane thing that the Romans taught us,” Klehm says. George agrees: “I don't think that the fundamental principle of mixing shit with drinking water and then paying a lot of money and using a lot of energy to remove the shit from drinking water is necessarily the best idea,” says George. “But it's too late, it's not going to be retrofitted.”
The UK is, George says, a faecalphobic culture: we don’t like talking or thinking about faeces and the flaws in our sewage system go broadly unacknowledged. “We have an aversion to coming into close contact with faeces, we want it to be flushed away and we want it to not smell and we want to not think about it,” she says. One of the measures of our failure to get to grips with it is in the language we use. None of our tools, she says, quite work: poop and poo are pretty childish; faeces and excrement are too medical; waste is wrong. The only appropriately direct term, thinks Rose George, is shit.
But this attitude wasn’t always there. “If you go back into the 19th Century,” says George, “there was a class of Victorian gentlemen who called themselves the Sewage Doctors who wanted to use sewage and didn't think it was waste. What they thought was wasteful was chucking it away and mixing it with drinking water, and that included Karl Marx.”
Marx likened the disposal of faeces into the water system to throwing gold sovereigns into the Thames. At the time, for traders of night soil, collecting bountiful craps from cesspits for resale brought a roaring trade. In China in 1908, it’s reported that a contractor paid the city of Shanghai $31,000 in gold to collect 78,000 tons of human waste.
But, up against the compelling public hygiene argument that households can’t be trusted to treat faeces safely, the Sewage Doctors lost the battle, ending up with an enormous infrastructure for swilling our waste away into potable water.
Hygiene expert Val Curtis at the London School of Hygiene and Tropical Medicine argues that faeces is something we should feel disgust for because it can do us harm. But, says George, while there may be an underlying biological aversion, “all these aversions to shit are pretty flexible over time and context”.
Once faeces has been mixed with water, there are no perfect ways of getting rid of it. They used to put it into rivers and the sea, George says, “but it ended up creating dead zones in the sea”, because it was too rich in phosphates and nitrates. Burying it isn’t a good idea – it can be disinterred – and incineration has terrible environmental implications. “You're kind of stuck with this stuff,” George says.
We may not talk about it much, but a lot of wastewater facilities in the UK do provide human manure for sparing use on land. After solids have been filtered and let to sink from fecal sludge, microorganisms are added to the mix, bolstered by oxygen, to break down toxins. This water is then pumped into nearby streams, but something still needs to be done with the dirty bit.
But because, as the fatberg illustrates, anything goes into sewage, this can lead to problems. In 2012 scientists found abornmalities in sheep grazing a field where human sludge had been scattered, thought to stem from hormones and prion contamination, rogue proteins that cause neurodegenerative diseases. There are, though, companies looking to technologise the process – extracting, for instance, just the clean phosphorus from night soil for crops.
For individuals, unless you're off the grid, composting is a bit of a grey area: in the UK, it was only in 2010 that building regulations began to mention compost loos under a drive to reduce domestic water consumption by 18 per cent. The main proviso was that it couldn't be carried out through living rooms and kitchens, but there is a lack of clear regulation from the Environment Agency and mostly composting falls to self-certification.
But the UK’s seemingly dyed-in-the-wool fecalphobia – as well as in the wider West – is not omnipresent. In India, George explains, where fecalphobia is strong and many people do die from diseases due to poor sanitation, cow dung is held in reverence and used to make bricks. In Japan, fear of excretion is so strong that a device called the Sound Princess has been invented to cover up the sound of women urinating, because so much water was being wasted by continual flushing.
In China, Ghana and Rwanda, by contrast, there are moves to create biogas from human dung. In the absence of oxygen, sewage and other once-live materials break down to make methane and carbon dioxide. The Rwandan state is trying out prisons as a testbed for this form of energy production, making biogas from prisoners bowels, and saving a lot of money on firewood. There are, in fact, various ways to reuse faeces, and doubtless undiscovered uses: RePOOPulate, for instance, has been trying to work out a way of doing fecal transplants to treat diarrhoea-causing C. difficile, with enormous potential.
"I would love to support more use of human shit as fertiliser but it's very difficult to encourage that in a modern, industrial, sewer-based system," says George with a hint of resignation. It might be too late for human manure to disrupt Westernised sewage on a mass scale – but there is still plenty we could be doing to safely mitigate wastage, and plenty more to do with poo.
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