I've got two drains, one with branches from the house and the other for inspection.
The inspection one has clean mains water running through, while the house one is dry,
but can hear the same running water (supply at house turned off).
Clealy have a leak, but this is plastic drain pipe and any water supply is also plastic.
It's never been distiurbed or drilled into etc. and no trees or roots anywhere near.
Can't figure out how mains can get in the soil pipe.
Anybody got any ideas?
Cheers Ed