I am planning to install lawn irrigation system and part of the challenge is running one supply pipe under 12 - 16 feet wide interlock driveway. Is there anyway for me to dig the line through without having to disassemble the driveway? The digout for the driveway was 17 inches below lawn grade and it has been filled with crushed stone. Is there a way to use water to dig the pipe through? Any recommendations? And I am assuming I have to go deeper than the crushed stone?