Have you ever tried yer' hand at dousing/ divination?
You take a couple welding rods and bend them into the shape of a long barrelled pistol there Wally ,with yer' elbows tucked into the sides of yer' ribs, and with a firm but loose grasp if the 'gun' grips you steadily advance like a two gun pistolero at the O.K. corral, they will swivel & intersect across each other in between yer' hands as you walk over the top of an under ground buried line,,,you will want to run a triangulation pattern for the most promising likely place to dig in order to locate yer' water inlet feed line,,,or you could call that 800 BLUE STAKE NUMBER IN YER PHONE BOOK,,,although they might only respond & mark yer utilities up to yer property line.