water stop ?

[ptonsparky]

I think they all drowned.

 

[Mr. Wizard]

The pressure will be about 1 psi for each 2.31 feet of water column above the opening.

Doesn't matter if it's a bathtub or the pacific ocean....the pressure will be the same at the same depth.
Well not actually, salt water is a little heavier than pure water, but you get the idea.:smile:

steve

I understand what you are saying, I think. If he is drilling 1 foot below the water line, pressure won't be so bad, but if he is drilling 5 feet down, the pressure will be enormous. But yes, at the same level the pressure will be the same. Either way, the OP is in for a mess. Not able to drain the pond? I think once that initial hole gets cored, that question will be answered - real quick.

 

[Mr. Wizard]

Hey, are you in South Dakota? Isn't the water frozen around this time of year, anyway? I guess I'm a pessimest, but with the situation you're in, I think it will be impossible without the owner allowing you to drain the pond - at least down to where you are coring.

 

[George Stolz]

I wish I had seen this thread when it was new, back in October. The visual images conjured by this task about made me fall out of my chair laughing. I'd tell the GC I'll wire his equipment when it's ready to go, including the hole.