By Tina Rosenberg
In America, I turn on the faucet and out pours water. In much of the world, no such luck. Nearly a billion people don’t have drinkable water. Lack of water ─ and the associated lack of toilets and proper hygiene ─ kills 3.3 million people a year, most of them children under five.
Lack of access to clean water is one of the world’s biggest health problems. And it is one of the hardest to solve. Lots of different groups dig wells and lay pipes ─ but the biggest challenge comes after the hardware is in.