Pouring concrete under water

[AlbertC]

I built a wood duck house to go beside my fishpond. I dug the hole where I want to put the post but before I could get the post installed we got 3" of rain and now my hole is underwater.

I have heard that you can pour concrete underwater but I'm not sure how to do this. Tried dipping the water out of the hole but it filled back up quicker than I could dip it out. If I mix the concrete and pour it in the 36" deep hole that I have dug the concrete will dissolve before it gets to the bottom of the hole.

Any ideas how to do this. I don't want to dig another hole further away from the edge because I want to put the duck house where I dug the original hole. Also don't want to wait till next summer to put up the duck house.

I thought about putting a garbage bag in the hole then putting in the post and then pouring the mixed concrete in the bag which will force the water out of the hole.

Any other ideas appreciated.

Post Extras:

 

[eray1066]

You could use a sonotube to deliver the concrete to the bottom unadulterated and it will force the water out similar to a "sock" we would use on a concrete bucket to deliver cement to the bottom of a flooded excavation. On a big job, We sometimes do the same with the cement pump hose to the bottom

 

[GPintheMitten]

Why couldn't you pour dry redi-mix in the hole?

 

[AlbertC]

I think if I were to just pour it in dry the rocks would sink to the bottom of the hole and most of the dry would float to the top and I would not get a good pour. The mix would be off. But I don't know if this is the case or not. Has anyone ever just poured the dry mix in the hole. I can see where thi might not be a proble if the hole was not very deep, but this hole is 36" deep.

 

[AlbertC]

If I put a sono tube in the hole it will just be full of water also. Wouldn't I have to try to pump the water out of the tube.

 

[GPintheMitten]

I'm picturing the duck house like a fence post with a box on it. Maybe it is more substantial than that.

I wouldn't pour dry mix in water filled hole for structure like deck or pole barn. I have used it for fence posts including those used to support farm gates. I haven't had problem with gate posts sagging or leaning.

 

[MikeInEburg]

Concrete curing is a chemical process. If you pre-mix properly, there should be no "dry" . Mix and pour into hole, and you should be fine.

 

[texas42]

You need to use a method called "tremie"
The tremie concrete placement method uses a pipe, through which concrete is placed below water level. The lower end of the pipe is kept immersed in fresh concrete so that the rising concrete from the bottom displaces the water without washing out the cement content.
You can do a search and get a good idea how to do it

 

[GPintheMitten]

If you wanted to get most of the water out could you get a sump pump to fit in the hole? I have an old sump pump that I have used to get water out of a trench.

Or you could get a plastic hand pump like this

ConservCo, Gulp UltraMax Water Removal Suction Pump, A-G12-C at The Home Depot - Mobile

 

[kevin37b]

properly mixed concrete will displace the water .

 

[AlbertC]

Texas42

I understand the concept of using the tremie but the hole is full of water. If I put a pipe in the hole the water is going to fill up the pipe so I am basically going to be pouring concrete into the pipe full of water. The hole is 12"in diameter and 36" deep. With the tremie method are you saying that the pipe I use should be a smaller diameter (say 5") so that after I pour concrete into the smaller pipe and force the water out then I can lift the pipe out of the hole and continue pouring concrete such that the concrete is deposited intact at the bottom of the hole and will force the water out of the hole. I think this is the concept, right.

 

[Ford850]

Texas42

I understand the concept of using the tremie but the hole is full of water. If I put a pipe in the hole the water is going to fill up the pipe so I am basically going to be pouring concrete into the pipe full of water. The hole is 12"in diameter and 36" deep. With the tremie method are you saying that the pipe I use should be a smaller diameter (say 5") so that after I pour concrete into the smaller pipe and force the water out then I can lift the pipe out of the hole and continue pouring concrete such that the concrete is deposited intact at the bottom of the hole and will force the water out of the hole. I think this is the concept, right.

That's how it's done. It doesn't have to be perfect with a relatively small hole like yours, but that process will work pretty decent.

 

[GPintheMitten]

I think the problem is smaller than these solutions but if you wanted too you could get a 4 or 5 in piece of pvc pipe about 4 foot long. Stand it on a scrap of plywood outside the hole. Then fI'll it with concrete. Then quickly move it into the hole. Then start lifting it out of the hole slowly so the concrete spills out if the bottom of the pipe. Fill the pipe as you go until the hole has as much concrete as you want. The concrete will displace the water from the hole.

 

[fordmantpw]

For this size hole, just mix the concrete properly and dump it in. The water will splash out the top and voila, you've poured concrete under water. If you want to be sure you displace ALL of the water, mix enough so that it fills the hole completely. Otherwise, the water will just sit on top of the concrete.

 

[Egon]

For this size hole, just mix the concrete properly and dump it in. The water will splash out the top and voila, you've poured concrete under water. If you want to be sure you displace ALL of the water, mix enough so that it fills the hole completely. Otherwise, the water will just sit on top of the concrete.

Quick and easy. Water sitting on the cocrete won't hurt much.

 

[bigtiller]

Let me be the fifth one to say that properly mixed concrete will displace the water in the hole. Try it.

 

[Streetcar]

I will be the sixth, just mix and pour concrete

 

[RobS]

Seventh...

 

[Billrog]

8th pour it in.

 

[jack707]

When I built my wood shed I had water and ice in the hole I pored the mix out of the bag used more water all was good. Why not use a long hose connected to a sump pump to get the water out.