Pool owner calls, My liner pool is leaking and I've heard that you can leak locate, not a problem we can do that.
Get to site to be told three other pool companies have been here and one of them did lots of digging but I still have a leak.
Look at the level, bottom of skimmers, does it stay there all the time, yes, even with all the rain.( of which we have had loads!)
So we inspect skimmer throats, water line, someone had obviously thought that the retaining ring for the basket in the skimmer was the cause and used a ton of putty.
Water is cold, so rather than plug sump we blow air down until it bubbles and then watch gauge as usually you get a few psi on the gauge and can get a clue as to pipe condition.
Well tried to blow air down, nothing, ok try the air blower rather than compressor, bigger volume, still nothing. A cold dip and plug it then, amongst all the debris nice, glad I have an assistant!
With a plug the line still didn't hold pressure, so left it plugged and now the pool is full to the top. Not dug it out yet but suspect a sheared pipe or split from frost damage. Just like the head of the boiler is split from frost damage, his ‘mate’ winterised for him......

like the fellow keeps saying dive!dive! dive!