when we inject Helium to an under ground pipe system, it behaves very similar to filling a balloon. A balloon filled with Helium wants to go up. The same is true when you put it under ground. The Helium finds it's way tho the surface where it can be detected with special equipment.
When a pipe line leaks with sufficient pressure behind it, the pipe vibrates at the point of the leak. This vibration can be heard with ultra sensitive listening equipment, and the area of the leak can be narrowed down.
Hot water breaks will create a hot spot that when coupled with locating the pipes position using thermal detection allows us to find the break under almost any substrate.
Q: What Causes my water line to leak?
A: A water line may leak for a multitude of reasons. Metal and plastic have different expansion and contraction rates and over long periods of time this difference can cause cracks in plastic threads. Tree roots can push through pipe. Poorly glued joints can come loose. Ground movement can cause breaks. A sharp rock up can rub a hole due to pipe vibration or even turbulence in elbows and Tees can eventually wear out the pipe.
Q: How do I know if I have an under ground Leak?
A: The easiest way to determine if you have an under ground leak is to find the main shut off at your house and close it. Then go look at your meter. There are two dials on most meters a large arm that looks like a second hand on a clock and a small red triangle. (see Picture) The small triangle is a low flow indicator. If this dial is turning after you have closed the main house valve you very likely have an under ground leak.