Tracing an underground cable fault?

Fifty years ago, when I was in my early teens, my dad was trying to locate a water pipe along with a guy from the water board who told my dad that he should not dabble in witchcraft.


I have not got a clue how it works, but it does. These rods are a bit flashy, I always used some bent wire or the like, but last year coming home from a job and stopped at the Rollright Stones and met Ron who lent me a set of rods to try in the stone circle, then proceeded to sell me these rods.


One impressive bit of dowsing was when i worked on a new housing site where the groundworkers laid the tarmac over the water meter covers in the footway, after his initial disbelief was dispelled the assistant agent walked down the footway with me and we marked all the service runs then tapped the tarmac and found the water meters for around twenty houses.


Ignore the people who kick up a fuss about people dowsing for service pipes and cables, just because they cannot find a rationale explanation for it working doesn’t mean that it doesn’t work.


I have had a few conversations with dowsers who claim they can dowse a map drawn on paper and the like, I can’t accept that works, but where there is a pipe or cable buried in the ground it usually works quite well.


Andy Betteridge

Dowsing rods usually "work" due to the ideomotor effect: they all rely on a mechanism which amplifies any subtle movement of the hands. Thus they move either because of subconscious changes of grip tension/angle etc, or due to external factors such as a slight change of incline of the ground.


Beyond that, you can debate to what extent such factors give good results, and to what extent it's luck / confirmation bias etc - e.g. the fact that England is a wet place and and if you pick any random spot there's a good chance there's water underneath.


James "The Amazing" Randi conducted a controlled experiment where a parallel run  of water pipes was buried, and one pipe at a time was randomly chosen to have water running though it. A group of dowsers all failed to do better than chance.

Think far more specific, walking backwards and forwards across a five acre field pushing in markers that form a nice straight line to reveal where the water pipe is buried.


Andy B.

I had just this problem many years ago in a 3rd world country. The fault was intermittent which I solved by putting 2 electrodes in a bath of slightly salty water in series so that the fault kept occurring but the breaker didn't trip.

Once I had a decent short circuit, I fed a known current down the cable to the fault and used the remaining length of the faulty core and a good core connected in series as a voltmeter lead to measure the volt drop from source to fault.

This gave a remarkably accurate location which turned out to be in a duct under a road so it must have been a manufacturing fault.