My question involves an easement in the state of:VA

I recently purchased a lot that has 2 deeded easements that benefit the property behind mine. One is a 15' driveway easement and the second a 12' water line easement. The easements are referenced from the side property line.

I am building on my lot and while excavating for footers yesterday we found (and cut) the waterline servicing the rear property. The line is approximately 25' onto my lot and crosses the only place to build a house.

I notified the adjacent absentee property owner. (The property is a vacant rental unit.) Current owner purchased the property in 2006. Information in the tax records indicate the house may have been built in the 1950's. The copper water line from the water meter to the house looks fairly new.

Owner is claiming a prescriptive easement for the line in its current location and has asked that I pay to move the line. Is an underground (hidden) waterline outside of a deeded easement sufficient to claim a prescriptive easement?

Thanks in advance for your advice.