You'll need to get an attorney to take steps to enforce your easement. City has no power here; courts do.
To questioners from West Virginia & New York: Although I am licensed to practice in your state (in WV, on inactive status as of 9/13), I practice on a day-to-day basis in Massachusetts. I answer questions in your state in areas of the law in which I practice, and in which I feel comfortable trying to offer you assistance based on my knowledge of specific statutes in your state and/or general principles applicable in all states. It is always best, however, to work with attorneys and court personnel in your own area to deal with specific problems and factual situations.
The reason the City won't help you is because this is a private matter concerning a private easement. You will need an attorney to file an injunction and enforce your rights to the easement.
The other attorneys here are correct. You basically have a property boundary dispute and if the facts are correct as you have stated here, then you should have a legal claim against the neighboring property owner for which a court can grant you a remedy. After filing a legal claim, the court may require you to go to mediation to work out a deal. More than likely, you need to hire a real estate property attorney licensed in your state to protect your rights.
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