Have you seen the suggestion floating around that the government should pay you for removing your sewage, rather than you paying to get rid of it?
Human sewage is once again becoming recognised as a valuable commodity. There is a looming global shortage of petrochemicals and other sources of fertiliser. We may rejoin Nature’s food chain, when what comes out of the earth is returned to it, by returning some at least of what we eat.
It is time to put a firm stake in the ground now, to assert strongly the principle that public gain is more important than private profit in what happens to our sewage. Once it leaves our property it must not become private property for sale. All profits from its many forms of re-use must be fully available to pay the costs of its removal and its re-use, plus the costs of research, development and re-development of sewerage infrastructure. This principle needs safeguarding by law.
Private enterprise is welcome at many points in developing and supplying new rings for the natural food chain, but it must not be allowed to compete to buy the raw products, and hence to raise the costs of using it. Infrastructure must not be duplicated for the sake of “competition”; the country cannot afford it.
In human sewage wastes we have two different types of resources - the liquid and the biosolids. In many places both can be reused at source without requiring sewerage to remove it from a property. Since agriculture began, and still in many countries, it has been essential that people return their excretion directly to the soil. Its organic matter improves the soil's structure, increases its water-holding capacity, feeds essential soil micro-organisms, prevents eutrophication of lakes and reservoirs through using artificial fertilisers and nourishes the growth of more food. In parts of Asia still, oxcarts, alias “honey-carts”, transport the waste of cities to the farms. But the serious problem is that untreated human waste can spread parasites and diseases like typhoid, cholera and dysentery, contaminating the food grown.
Now there are more people, and we eat more - producing enormous amounts of sewage. Since the invention of the water closet for disease-free removal of human waste, disposal has become an enormous problem, instead of an asset. New York City alone produces about 1,200 tons of sewage sludge every day. Estimates of sewage production in the United States range from 60 to 115 gallons per person per day .(227 to 435 litres) excluding industrial effluents. The usual cheap treatment has been to pollute seas and watercourses. But this is having dangerous consequences. There will be a crisis if present forms of Western sanitation take over for the billions of other humans in the world.
Robert Brobst of the US Environmental Protection Authority Region 8, reports that on the eastern plains of Colorado, half of the organic matter has disappeared since farming began. Most of Australia has very poor soils, and there are horrendous calculations about how many kilos of fertile topsoil are lost for every kilo of wheat that is exported. Artificial fertilisers to supply nutrients do not replace the organic structure of the soil.
We feel repugnance to using our own faeces for any purpose, for good reason. Their horrible smell is nature's way of warning us to keep our excreta well away from us to avoid disease and parasites. Today it can also pollute (PDF 722KB), because we excrete toxins and dangerous metals like cadmium and mercury that we consume with our modern diet. Our sewage systems also carry the other effluents that humans put down domestic and industrial drains.
These are big but soluble problems. The costs of a solution are mainly borne by the public purse because at present sewerage is not profitable. But profits could become big. We should not allow any risk of “returns for shareholders” taking over, and benefiting from the public expense and investment that has been made.
Action is needed at both domestic and national levels. What can be done?
Many individual households are starting to use various types of “eco-toilets” that produce their own compost for local use. Some models are not completely “environmentally friendly” because they need electricity for ventilation fans or pumping, but better models are being developed.
Re-planning sewage disposal, thinking in terms of using, rather than disposing of “waste”
Urban areas, especially, require innovative re-planning including possibly rebuilding complete drainage systems, with the aim of using rather than “disposing” of waste. The chief urgency is how to treat and use biosolids, the nutrient-rich solid material that is removed from sewage at waste-water treatment facilities. Sewage sludge is put through a series of biological transformations in which most of the complex organic molecules are decomposed and most of the pathogens are killed.
Biosolid composts are being developed for soil blending, landfill cover, mine reclamation, degrading toxins, fertilising golf-courses, even as fuels. “With chemical fertilisers, you feed the plant directly. With sludge, you feed the soil, building it up by feeding naturally occurring bacteria.” (Robert Brobst.)
Ways are also being developed to prevent the problem of biosolids permeating into water systems, as can happen with septic tanks. Current types of sewage disposal programs cannot be allowed on ground which may be permeable, to contaminate groundwater, or potentially runoff into water-courses. Other questions being tackled include the quality of food grown with these organic fertilisers.
Liquid human waste
Human urine costs a tremendous amount of water to flush it down lavatory water-closets - from three to 11 litres a flush - and even water-saving means of disposal through sewerage systems are still usually wasting a potential resource, although this will change. Urine has been put to many uses in the past, and still today, from medicines to bleaching and treating materials such as Harris tweed.
There are ways to use urine at source for gardens, added to compost, since fresh urine is sterile, although caustic for worm-farms or directly on plants without dilution. Householders can make dramatic differences in their water bills, although some fluids must still keep drains flowing.
Drinking water recycled from the sewerage system is being urged upon us as we continue to rashly increase population and droughts are becoming more prolonged. Living in Melbourne, which has been proud of having “the best tapwater for drinking in the world”, I object to this solution. Let us act on the causes of shortages of pure water - including over-populating.
Bottled-water manufacturers aim for great profits when tap water is recycled sewage - and scandalously they are allowed to bottle cheaply from our own springs. Let us work on the many possible strategies to use water recycled from sewage for other purposes - but let us still be able to enjoy drinking rainwater from the tap, and not from environmentally-costly plastic bottles or the sewage farm. Quality of life is an aim of No More Waste - not even of waste.