My property has a sewer eastment beween 2 homes. I was allowed to put up a 6 foot fence but if it ever needs removed for sewer work removal and replacemnents at my cost...
the best option is a low profile fence eplacement of the existing wire fence with something similiar and plead ignorance if caught. or you can hire a fence crew to do a FAST one day preferably weekend fence replavcement but know they might make you remove it......
another idea is call some local fence contractors and ask for opinions, they want your $ selling you a fence and no doubt have run into this rule before and will know best how to proceed...