Depends on what you build them out of. 15' is pretty long and it has to support hose, fittings, nozzels and the breakaway hinges. It has to be strong enough to absorb shock loads and enough force to the point that the breakaway hinges give if you hang up on something. You might want to look into a truss structure or something with a cantelever and top strain wire or kingpost and wire. This would allow you to build lighter for a given strength and lessen the shock load forces as things bounce around.