LEAKY water mains can be pinpointed quickly and cheaply with a technique that
builds up a three-dimensional picture of the ground beneath our feet. The
technique should make it easier to reduce the amount of water lost through
leaks—which can waste more than a third of the water that should reach our
taps.
Leaks from underground mains are usually not discovered until the water
pressure drops, or water spurts from the ground. Before digging up the road,
engineers locate the leak with a metal rod or “listening stick” that picks up
the hiss of escaping water when placed on…
