Undergound Water Line Repairs

I have a water leak somewhere in the main lines of a park. We are having a very difficult time locating it, though we all have our suspicions of its location(s). Because it has cost us an extra $500-$1000 each of the last few months we are anxious to find it.

One of those suspected areas is a trunk line, and its junction, that feeds 6 trailers. It T’s off in 4 different directions here. Ironically, we find ourselves in a position where each of these trailers can go without water for a while due to vacancies, people off-site for season, etc… I want to use this time to trench a new line and replace that section of the water line and risers. We’ve been having trouble with that area for a long time and its a real mess anyways because over the years its been haphazardly fixed numerous times (before I owned the park).

My question is what is the best material to use these days to replace an entire section like this? My plumber in another park uses some high end plastic material that has a 50 or 70 year service life but I haven’t been able to reach him this week and I’d like to get started ASAP.

Any assistance would be appreciated.