Water loss is often referred to as non-revenue water (NRW) – water that is produced in a network but never reaches the consumer. This might be due to aging networks which haven’t been properly managed, metering inaccuracies, theft or unmetered authorized consumption, like water used from fire hydrants.
It’s not a problem restricted only to the developing world either – Montreal, for example, loses 40% of the water it produces (pdf).
