You should have asked this question prior to closing. This would have been a great negotiating point. Now it is up to you.
Whomever you used to close this sale (attorney, Realtor, etc.), go back to them and get some answers. IMHO they owe you.
Without knowing your situation in its entirety, the complete answer is impossible. Please contact me for other questions.
How did this problem come to your attention? Did you have a survey done, or did the seller disclose it to you at closing?
Easements/encroachments are extremely difficult to have fixed. You will have to call a local real estate attorney and have them look into this. If its a utility easement, basically your city will have the right to come in and do any kind of work that needs to be done where the utility line runs. If your house runs on the corner of the utility easement, they don't have to fix anything on your home in the event they need to access where your house crosses that path. Talk to whoever told you this and dig a little deeper. Or talk to your real estate attorney to find out what type of easement/enroachmenth this is.