I own a townhouse in a triplex and have a water leak coming from the neighbors slab. I thought it was my waterline running from the street up to the turn off valve but after many test and digging it's not coming from my line. My line runs parallel with the neighbors slab. I dug down to her slab and could see water running out of the neighbors slab.
This morning I emptied a freshly dug hole of all water. I turned the neighbors water off at the street and drained her lines from the lowest hose bib, within 2 hours the hole had 8 inches of water. With all three units water turned off at the street the water continues to flow out from the neighbors slab. This continued all day today with the water turned off at the street. What can I do to find the source of the water?