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View Full Version : Digging for footers - ran into water!



Greg Woloshyn
03-16-2010, 12:42 PM
Hey all, Im working on a floor for my new shop and this requires digging footings which I started today. I went down about 42" and now my hole is filling with water. If I wait will the warmer weather fix this problem because I cant see anything good coming from pouring a sonitube footer with standing water at the bottom of the hole. Also, the soil is mushy at my 42" depth and I cant pour a footer on this.

Chris Padilla
03-16-2010, 12:46 PM
You might check with the city to see if any geological water table work has been done around your area. Are you aware of any instances of a high water table in your area? Neighbors, utilities, etc.? Lottsa rain lately?

Greg Woloshyn
03-16-2010, 1:19 PM
I'm right on the border of lake ontario, the houses across the street are waterfront. Also, there has been a great deal of snow thawing around here which is probably the cause.

Is this going to seriously interrupt my plans of installing footers 4 feet deep?

Myk Rian
03-16-2010, 1:32 PM
Is this going to seriously interrupt my plans of installing footers 4 feet deep?
Not if you're willing to wait. As you say, the snow is thawing, it sinks into the ground, and you have found it.
Give it some time.

Mike Zilis
03-16-2010, 3:46 PM
Besides waiting, I understand there is a concrete you can use that will cure in and under water. I'm no expert on this so there may be other reasons this wouldn't work for you. As stupid as I'm making myself sound, I saw this product used on "Holmes on Homes".

-Mike

Chris Padilla
03-16-2010, 7:21 PM
Can you pump out the water and if so, does it return and how quickly? How many footers do you need to dig? Try one or two more and see if they act the same. Maybe dig a footer as far from this one as you can. Good Luck

Scott T Smith
03-16-2010, 11:32 PM
Drilled shaft (aka caisson foundations) are typically drilled with the hole flooded with water and "drillers mud" to stabilize the sides of the hole. When the concrete is placed the water is displaced and the foundation sets up in place.

Additionally, foundations can be placed whereby a system of pipes is embedded in the ground and connected to a suction pump which will remove the water. This is commonly referred to as a "well point dewatering system", and information is available about it on the internet.

Where I'm headed here is that having water in the bottom of a foundation hole does not necessarily require you to delay your project.

If the material at the bottom of your footer holes has inadequate bearing when wet, your foundations should be designed to compensate for this. You may need to have a soil analysis performed in order to be sure.

Curt Fuller
03-17-2010, 9:12 PM
There's no problem with water in the footings. It's probably always been there and will come back after you pump it out. I drive a concrete mixer and deliver to sites with water in the hole all the time. Keep the concrete at a low slump (fairly dry) and it will just push the water to the top and out of the hole. In fact, the water will allow the concrete to cure stronger than if it were in a dry hole. Just mix it as dry as you can handle it to prevent it from mixing with the water in the hole.