For the sake of clarifying the question, I'll offer this hypothetical.

Assume I had a neighbor down the street and I wanted to run a cable between our homes. There is an existing utility easement running along the street.

Is it possible to take advantage of that easement to bridge across other people's properties like the phone,electric and cable companies do? Who would you even talk to if you wanted to find out?

Update for clarification per the comments: I am in the United States, in a rural area outside of Austin Texas.