I need advice on detecting source of main line water leak. Following a 30% increase in my bill I have isolated the leak/s to the pipe leading to the house. I found a leak near the meter where copper joins pvc but which leak only accounts for 12oz per hr or about 35gall pm whereas my overall loss rate is close to 1000gall pm. The line is about 200'long and I cannot find any damp spots or weeds growing so without digging up the whole length I would like to find other ways of locating this main leak. I have researched a firm which specializes in leak location and called them but they were not very helpful and were reluctant to answer any questions so before making appointment I checked them out with bbb and yelp and the reviews were real bad. I was thinking of injecting compressed air into the line bia the hose bib but am concerned that I may make things worse. I had a local plumber stop by and they suggested just digging a new trench and installing a plex line, something I may end up having to do, but before that would like to explore alternatives.

 

Sounds like you're saying the leak is before the meter. Generally speaking, water leaks leading to the meter are the responsibility of the water company. More importantly, though, a leak before the meter should have no impact on the meter or your bill. Your local plumber should know that.

 

With a residential water line if you can't find it with the methods you've already tried you usually dig and install a new line. If are in the south and know where the line is located you can probe along the length but even that's not very reliable. Location services are rather expensive for such a small job so it's not commonly done.

 

Does the PVC enter the house or is there another connection like the one near the meter.

If copper enters the house then that is where I would dig to find the second underground connection.

I am assuming you have closed the mains shut off in the house just to be sure that the leak is not in the house.

 

Leak is between water meter and house, i.e. not in house. Water Co are only responsible for leaks on their side of the meter. Apart from that, they are useless as I have called them a week ago with leak detection question and am still awaiting callback.
I have started to dig around house end and the pipe joining the house shutoff valve is copper. Am still in the process of digging deeper and longer trench as it probably joins to pvc similar to that of meter end and I would guess that most leaks are at a pipe joint, indeed as I found at at the meter end. So far there is no sign as of yet.

 

Infrared cameras can be used to find underground water line leaks, but it would be pretty expensive for your small project.


https://www.efficientplantmag.com/20...rground-leaks/

 

I've spotted leaks with my FLIR. You really have to know how to interpret thermal results as variations in the soil, grass and shadows cause a lot of confusion. The time of year and weather also have a huge impact on detection ability. If it's early in fall when the water is still warm a leak is easier to spot after a cold snap. Later in the season the water temp can be much lower making it tough to spot during daylight when the sun has warmed the ground surface a bit. Looking very early in the morning when the ground is it's coldest and before the sun has risen is the best time to look.