I agree with my colleague, a lot would depend on the language of the easement as well as history of the use and maintenance of the easement. Typically, without any language or contrary intent, users of an easement should be able to provide reasonable repairs to maintain the use and enjoyment of the easement. I would try to find out the reason the owner is refusing and try to come to a compromise that takes into account the easement users and the owner. Otherwise, you may have some rights but it may take some time and expense to enforce them.
I can't speak to the legal technicalities of the easement - that will require you going to a lawyer to read and review the exact language. But I can speak to the practicality. I don't see why the homeowner would completely object to you filling in the potholes especially with your own labor and expense. He probably is concerned with your ability to do it without harming his bushes or his property. Maybe a friendly discussion where you and the owner decide how this can be done without causing him problems would solve the issue. I might show up at his house with a couple of cold beers and say "can we talk" or a cup of coffee or some peace offering - maybe even fresh baked brownies. My guess is that there is some other prior issue that is causing you a problem with getting cooperation. Try winning him over first. http://www.portlandlegalservices.com
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