Legal/experience question and in need of excavator - sewer issue

[Wendell Clark]

Background:  I live in Frankfort, KY and the City does not have any record of having an easement for the sewer line or drawing where the sewer line runs once it is off my property. 
1.  With no apparent easement, am I responsible for replacing and repairing my sewer line that runs from the edge of my property down 30 yards to connect with the City's main?  If my neighbor refuses is my only recourse a lawsuit?  It appears the old line is terra cotta and eventually will need replacing.

2.  Does anyone in Central KY know someone with an excavator that I can hire to dig up the line to figure out precisely what I am facing?