This article discusses the problems many cities are facing regarding drinking water. Capturing and reusing urban storm water could be a boon for water-stressed cities—if we can find a way to clean it up. 3 promising new technologies could help send storm water to taps in thirsty cities.
In March, residents of Cape Town, South Africa stood in line for hours to buy drinking water at supermarkets or pump it from springs amid severe water shortages.
Cape Town isn’t alone: One in four big cities worldwide already has overstretched its water resources, and global warming may increase the likelihood of prolonged dry spells in some regions.
Facing a future of increasingly erratic rains, water-stressed cities are looking for solutions. One alluring possibility? The capture and reuse of storm water. But the water infrastructure of most cities was built with a single problem in mind: flood prevention. In Los Angeles, for instance, the U.S. Army Corps of Engineers developed a massive network of concrete channels to divert storm water to the ocean after a massive flood in 1938 killed more than 100 people.