The sounds of leaks in pressurized water pipes can travel for hundreds (even thousands) of feet in every direction down the mains and services. If there is no evidence of the leak, then compare the loudness of the leak sounds at the meters, valves, and hydrants:
When you have found the two meters, valves, or hydrants with the loudest leak sounds, you are ready to begin the final “pinpointing”. First, mark the exact location of the pipe between the two loudest valves, meters, hydrants, etc. with a pipe locator. Then listen every 2-3 feet directly over the pipe.
Different pipe materials and different pipe diameters transmit leak sounds down their pipe walls very differently:
Iron Pipe
6 inch
1000 — 1200 ft
Iron Pipe
12 inch
800 — 1000 ft
Iron Pipe
24 inch
600 — 800 ft
AC Pipe
6 inch
800 — 1000 ft
AC Pipe
12 inch
700 — 900 ft
AC Pipe
24 inch
400 — 600 ft
PVC Pipe
6 inch
400 — 600 ft
PVC Pipe
12 inch
200 — 300 ft
PVC Pipe
24 inch
100— 150 ft
*For 5 gal/min leak at 60 psi pressure
Water leak surveying at meters is often performed using a long contact rod:
Touch the tip of the rod on the brass shut off valve.
Listen and use the meter display
to compare the loudness at different locations.
Use your hearing and the meter display to determine exactly where the leak sound is loudest:
For water leak pinpointing, attach the base plate to the sensor’s magnet and listen directly over the pipe:
Press the
Mute Switch
only when the
base plate is
sitting firmly
on the street.
Listen and move the sensor every
few feet directly over the pipe.
The Long Contact Rods are NOT digging bars or probe rods. The sensor can be broken if the rod is pounded into the ground.
