"If you see me, weep," are the words inscribed on a boulder that was exposed as water levels receded on the Elbe River in the Czech Republic this summer. It was one of many so-called hunger stones that were carved over the years to commemorate historic drought levels. Lately these markers — and other landmarks like them — have been appearing much more regularly. As Lake Mead dried up this summer, there were grisly discoveries like human remains.
The United Nations estimates that 380 billion cubic meters of water can be recovered annually from wastewater and it predicts that figure could rise to 574 billion cubic meters by 2050. Treated wastewater can be used for drinking water or funneled for industrial or agricultural uses. "In the U.S. people immediately say, 'Oh, from the toilet to tap? That's disgusting. Don't ever even think of that.' But the folks in Singapore, by necessity have started to," Dray said.