water stop ?

[dan55]

we have a job where we are drilling have to drill through a concrete wall into a pond for a pond aerator. conduit entering the pond will be a 4 inch sleeve. we are going to put a link seal around the conduit to seal there but the problem is finding a water stop to put into the end of the conduit allowing us to pull the aerator cables later. draining the pond is not an option. Impossible?

[electricalperson]

are you drilling into a full pond? what about all the water that will shoot out when you make it through?

[stickboy1375]

Why not install a ground box by the pond and install a receptacle inside of that for easy removal of the pond aerator?

[dan55]

these are big aerators 480 volt 3 phase and it is a full pond, we are going to drill into the pond with a piece of plywood against the inside of the pond to hold the water out of our hole. general contractor we are working with says they have done this before and it will work.

[ivsenroute]

Good luck on this one.

How deep under water will the drilling be done & how big is the pond? (pressure from pond)

Will the conduit will be be able to come to the surface before you pull wire?

What about the seal between the conduit and the concrete while you are pushing it through? (major leaking point)

You may need to cap the other end of the conduit inside the dry area until the other side is connected then drain that water later.

I am not saying this is impossible but I think it is very close and will be a little messy.

Let us know how you made out,

Jeff

[electricalperson]

that sounds like a worst possible senerio happening would involve tons of water shooting everywhere. why cant you drain the pond a little?

[brantmacga]

but the problem is finding a water stop to put into the end of the conduit allowing us to pull the aerator cables later.

are you just looking for a way to keep water out of the conduit? You can try to tape the end of it, or just get a PVC cap.


we are going to drill into the pond with a piece of plywood against the inside of the pond to hold the water out of our hole. general contractor we are working with says they have done this before and it will work.

If that looks like it isn't going to work that well, you could build a small caisson (4'x6' ?). Cut a hole at the bottom and make a patch for it that can be removed quickly for the conduit to go through. When you're done, you just lift it out of the water. Of course you'll have to get a pump to empty the caisson. How deep is the pond where you're going through the wall?

[tkb]

these are big aerators 480 volt 3 phase and it is a full pond, we are going to drill into the pond with a piece of plywood against the inside of the pond to hold the water out of our hole. general contractor we are working with says they have done this before and it will work.

I would love to see this. :grin:
If it was so easy the GC would do it their selves.

Please video it for us.
You could win $10,000 on the Home Video Show.

It will be a gusher that you won't be able to stop until the pond is dry.

[stickboy1375]

I cant wait to see the outcome of this one either... I know the worst case scenario thats for sure...

[alfiesauce]

If you are pulling a single cable through this conduit after the conduit is installed and the pond is still full think about this-
cap both ends of your pipe with a standard pvc pipe cap with a hole in it just over the size of your wire pull a string through it then stuff it full of yellow 77 or something like that. Tape each end to keep it all contained and integral.
when you are ready to pull you can tie onto your pull string and pull pull pull. I'd pull the wire from the pond side to the outside- just to keep the 77 from contaminating the pond to much.
Soo to sum up-
Maybe that will work like a grease barrier? And then while your pulling you can contain the "grease" tubes integrity and have a drainless pull.

I lay awake all night thinking about solutions sometimes... It hurts my head.

[stickboy1375]

Do you guys really realize the pressure of water?

[brantmacga]

Do you guys really realize the pressure of water?

depends on how much water. i think my caisson idea will work.

[brennan]

Make sure you use a GFI.

[William1978]

I would suggest waiting on an drought before drilling that hole.:D

[LHarrington]

All my money is going on the water, water always wins.

LHarrington

[bjp_ne_elec]

depends on how much water. i think my caisson idea will work.

Can you elaborate more?

[brantmacga]

Can you elaborate more?

read my post on page 1 of this thread.

[dan55]

attempted to dam up an area where the holes are being drillied with sandbags and tarps and pumping out a big enough area to drill holes. NO LUCK

[hillbilly]

Do you guys really realize the pressure of water?


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

[tkb]

Did this ever get done.
I wonder what the outcome was?

[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.