Have you ever had an underground water leak and just couldn't find it? Or perhaps you're trying to learn how to find an underground water source, like a pipe or a spring... ...you'll definitely want to give this a try. 1. Grab two utility marking flags. (Wire hangers can also be used) 2. Pull off the plastic flag portion, leaving you with two metal rods. 3. Bend 1/3 of each flag down creating a 90 degree angle with the rod. 4. Make the sign language letter "O" with your hand