Any industry that mislays 25-30% of its product in the process of delivering it might reasonably be thought to have a problem. Yet that, according to the World Bank, is the case for the world’s water companies. Though water is cheap, it is not free. According to a report published by the Bank in 2006, leaks even then were costing $14 billion a year. But to plug a leak you have to find it. Water mains are hard to inspect, particularly if they are underground. Many are old and thus decrepit. And outright theft is not unheard of, as the poor seek to fill their drinking vessels and the rich their swimming pools. An effective way of detecting leaks, both accidental and deliberate, would therefore be welcome. Read More