Looking for help in easement question

Situation
Original parcel was divided 20 years ago into eight separate parcels all served by one private road. Easement is recorded in each parcel's deed. Surveyed description of easement is present but no discussion of maintenance is present. Past practice was that each property owner maintained the road in front of their property.

The private road crosses a creek directly off the public road with a 60" concrete culvert. In the past year the property owner in this section has had maintenance performed mainly on the creek (200') but also to remove debris clogging the culvert.

Today I recieved a letter from his lawyer stating that I (as well as only 3 other parcel owners) was expected to pay part of the future maintenance on his road/culvert/creek.

My concerns
-He is picking and choosing who he wants to financially help out
-I should not be responsible for creek maintenance outside of the road easement
-If the landowner is responsible for taking care of maintenance he could use that to doctor contractor information/make side deals, ect., basically stick the rest of us with costs not related to the easement

What are my legal responsibilities for maintenance if not stated on the deed? How would a judge typically determine this? Could I be looking at a court case every time he wants to hire a backhoe?

I don't care to help with the road maintenance costs but I don't trust this guy. I have lived here for a year and the only time this guy has talked to me was to yell that I didn't help clean the culvert (he never asked).

Any help is appreciated.