Is it normal to find water under basement concrete?

11/27/2014 at 9:39:42 PM

Yes that is normal, Rita. When you broke the concrete you should have first a thick poly vapor barrier and then about 4" of stone to dig through to. This is all part of he drainage system under your house leading to the sump pump.

11/30/2014 at 11:28:17 AM

Hi Rita,

Just to give you a little clarity on the process of home building, when foundations are poured, as well as basement concrete, they excavate the earth below where your hours is to a level that has undisturbed earth so that it will be strong and sturdy to build upon. Once the footings are in place and the foundation walls set, they will usually back fill the earth in the basement with gravel and then pour concrete on top. Once they finish the foundation they will put a waterproofing membrane around the walls, this will not allow water to penetrate your home and will cause the water to seep down through the earth that they used to fill in around your house that has been disturbed, and will gather in a system called your weeping tile system. This system if in an area that has a higher water table, meaning the ground water level in that geographical area sits higher in the ground than the footings and foundation, will all run and be diverted into a sump pump, that will store all the water around your house that has been gathered in your pit and sucks it out and pushes it away from your house.

That said, the water will also come up from underneath the house as well, but because there is undisturbed soil, it will usually just stay stagnant there, and remain only in the bottom portion of the gravel that was placed before the concrete. It is normal that when you renovate the basement and have to dig and trench for plumbing rough ins that you are now digging into this undisturbed soil and if you have a higher water table, or even sometimes not, the stagnant water in the soil and earth will now pool in this dug out area. It is normal because usually the height of the water does not exceed the height of the gravel that you install when back filling the hole. And it will not cause any problems moving forward either.

I hope this explanation helps some. Good luck with your project.