[mrsmith2211 (OP)]

I did not see much about dowsing here. It is an extreme last measure for us old timers for finding lost underground utilities, with better than chance success. We were having electric buried, and I marked out water, sewer, cable and electric with an acceptable amount of accuracy. Now my 82 year old mom wanted to try it, she had no idea where underground utilities were. I gave her the say 3" x 9" bent coat hangers, hold loosely (3" part) and balance to level as best you can with long side pointing forward. I told her to walk ahead and see what happens. She walked ahead and the rods swung 90 degrees. She was like what? and I noted she had crossed the sanitary pipe from the bunkhouse. She tried a few other places and replicated underground utilities I had found.
I told her don't tell your friends as they will think you are crazy, and will be unwilling to try it.
She told her friends, they called her crazy and were unwilling to try it.
So One sister was up, mom talked her into trying it and as soon as the rods moved she dropped them like a red potatoe and refused to try it again. So mom tried it with my other sis who is half paralyzed from a stroke and nothing.
Now it works for me, and are any of you courageous enough to take an old metal coat hanger, cut 2 12" straight piece, bend 3" at 90 degrees, balance them level and loosely in your hand with the long edge resting loosely on your index finger pointed forward, then walk along the sidewalk in front of your house and report your findings?
If you wish you can always call diggers hotline or julie to mark out underground utilities if you have a replicate able  experience, call it a planning ticket, for landscaping.

[Bored chemist]

All proper tests  of dowsing ability have shown that it isn't real.

"A 1948 study tested 58 dowsers' ability to detect water. None of them was more reliable than chance.[35] A 1979 review examined many controlled studies of dowsing for water, and found that none of them showed better than chance results.[2] A 2006 study of grave dowsing in Iowa reviewed 14 published studies and determined that none of them correctly predicted the location of human burials, and simple scientific experiments demonstrated that the fundamental principles commonly used to explain grave dowsing were incorrect.[36]
A randomized double-blind trial in 2012 was carried out to determine whether homeopaths were able to distinguish between Bryonia and placebo by use of a dowsing method. The results were negative.[37]"

from
https://en.wikipedia.org/wiki/Dowsing#Scientific_reception
When you say " better than chance success."
How did you calculate that?
Similarly, what does "an acceptable amount of accuracy." mean?

[RD]

http://rationalwiki.org/wiki/Dowsing#Random_chance