Urine diversion could be the future of loos. Posh Swiss toilet manufacturer Laufen has a toilet called Save. You use it as you would any other toilet, with one gender caveat. Before the flush, the urine runs down the front of the gleaming ceramic bowl to be diverted to a separate pipe. So men and boys have to sit down to pee. A greener loo with less mess. What’s not to love? Urine diversion is being trialled around the world. Sanitation codes are being rewritten to turn a pollutant into a resource.
Environmental consultant Feidhlim Harty ends his book Septic Tank Options and Alternatives with the hope for a future when “sewage pollution of our groundwater, rivers and streams is a distant memory of a temporary madness.” Dry toilets, or compost loos, could keep so much pollution out of our water system. But they are niche. Waste-water treatment consultant Ollan Herr’s bar is that the in-laws should be comfortable using the toilet. Regular-looking loos that do more are coming to modern building design.
Fertiliser
The win-win is the harvesting of human waste for use as fertiliser. Urine is a rich source of nitrogen and modern systems could separate and dry or concentrate it for removal. Solid waste also has potential. Night soil, humanure or whatever you want to call it is a resource. Thames Water produces biosolids from wastewater treatment and sells it to farmers in England. “The war in Ukraine is bringing into focus the growing threat of a possible future food supply crisis,” Herr says. Phosphorus is a dwindling non-renewable resource. The main deposits are in Morocco, China, the US and Russia.
Eco sewage experts such as Harty and Herr design systems that transform human waste from a problem into a solution. Constructed wetlands, reed-bed systems and willow can use waste to produce coppiced willow for fuel, which captures the nutrients leaving nothing to run off. Throw in the looming fertiliser crisis when, as Herr puts it, “mankind is still wasting so much of the nitrogen and phosphorus from domestic and municipal wastewater”. Something has to change.
Flower-growing
Herr sells an Aquatron system which separates and stores the urine. One of the options incorporates flower-growing into his system. Irish sanitation regulations need to recognise natural systems which can help resolve pollution problems and improve food security.
The WHO has published guidelines for the safe use of human waste and grey water in agriculture. These are changes that could leave us feeling flush.
www.wetlandsystems.ie; www.herr.ie
Catherine Cleary is co-founder of Pocket Forests
