Easement rights

I am attempting to buy an old property to live in and remodel. The property sewer is currently in an old septic that is unacceptable. This propoerty is in City Limits. I would like to run sewer line to city sewer main. It is on neighbors property and I would have to go in them less than 6 feet. The city tells me that they have no Easement! The neighbor states that he will give no Easement. I don't know if I am allowed to place a new septic on property or not. There is no other option than boring under a road that would cost around $10,000.00. This seems ridiculous but what should I do.

Get to a local real estate lawyer as the applicable laws and customs are usually very local.

Or, see if you can BUY an easement from your neighbor. It probably would cost a lot less than $10k.