This story is funny but I can tell you with 100% certainty that I can find a water line using "witching sticks" (thats what we call them around here). I'm a municipal engineer and responsible for capital project design and construction. Well often our records are so old that the information required is not on them. So I'll go out in the field and usually through proper reasoning I can decipher where existing water lines are. However, when it doubt I using the witching rods and they work pretty often. I always double check with a hydro-ex crew and I'm surprised how accurate they can be.
Here's another one, we were once pressurizing a new watermain and we were losing pounds which indicated a leakage somewhere in the main. Basically we narrowed it down to a section approx. 300m long between 2 valves. We let it go overnight to see if it would surface. No luck. Next day the public works foreman comes around, takes out an old Doctors Stethoscope and starts listening to the ground. Sure and **** the guy found it within 5 mins. Saved the contractor a ton.
I have located storm and sewer lines using ell shaped brazing rod. I was pretty accurate. Watched the head guy of the water dept use a "store bought" pair locate 4" fire line too. I have also used leak detection stethoscopes to find a leak in a 2" drain line- turns out it was hit with a back hoe tooth. This was under a slab in the schools cafeteria.
All these systems do work but a quarter in a glass of water?
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