Would you like a glass of sewage? No? There’s no reason why not. You’re drinking it anyway. All water is recycled: Your ice cream probably contains the same water that dinosaurs drank. Countless human settlements discharge cleaned sewage effluent into watercourses from which other settlements take drinking water: Las Vegas’ treated sewage goes into Lake Mead. Lake Mead flows to the Colorado River. San Diego drinks the river.
By 2025, 1.8 billion people will be living in places that don’t have enough water to grow the food their inhabitants need.
But still people don’t want to drink cleaned sewage, though soon they will have no choice. This is a blue planet, but less than 1 percent of its water is drinkable (the rest is salty or frozen). In 2000, twice as much water was used – mostly by agriculture – as in 1960. By 2025, 1.8 billion people will be living in places that don’t have enough water to grow the food their inhabitants need.
One solution is to stop throwing wastewater into the ocean, and to stop thinking it is waste. Orange County in the US state of California now recycles its wastewater into the drinking kind. Its Groundwater Replenishment System purifies sewage effluent to the point where it is cleaner than river water, using reverse osmosis (a hi-tech membrane), UV light and hydrogen peroxide. But even that technology can’t counteract the “yuck factor.” Opponents talk of “toilet to tap” and say only dogs should drink from toilets. Dogs and Namibians: the residents of Windhoek, an arid city in an arid country, have drunk 100 percent recycled wastewater for years, because they have no choice. Population growth means more states in the US will have to do the same, yuck factor or not. Cheers.