That certainly is a odd looking connection in the middle. Just looking at the arrangement makes me think it might be a pressure regulator since they already have isolation valves on each end. See the wires coming out of the ground at each end wrapped around the pipes, those are for locating the underground path of the pipes. Paul
Dave - that makes sense, except that I don't recall seeing any others of these in our subdivision. There may be others, but I don't recall them. I'll have to keep a better eye out.
I don't know for sure, but I would guess that this is a shut off point in case of a failure underground. You wouldn't have to shut down the entire pipeline, just where it's damaged. davev.