Though I have not yet proved it, I am 90% sure my neighbors' tall rooty tree has compromised my sewer line. A month after I moved in I had to snake the main line that runs straight into the street. I calculated the root ball to have been about 75' away from entry point which puts it near the boundary on my property and that of the City street; very near the neighbors tree. Ten months later I had to snake it again and again the root ball was about 75' away from entry point. Its been over a year now, treating sewer line with Root Kill on a bi-monthly basis has probably eased up the issue (knock on wood). Short of scoping the line with a camera to find out exact location of damage. Can I prove and get the tree owner to pay for damages and any upcoming fees? What if its on the city's side?