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Community and Q&A

Sealing a dry well in my Z5, CT, 1953 basement

jenniferz5 | Posted in General Questions on

A plumber came out to the house last week and told me that the solution to my basement flooding issue was to seal up the dry well with hydraulic cement, and permanently seal the drains.  His reasoning was that, since we have only had flooding this year because of the high water table, and only from the dry well and the basement drains – not from any other sources – a sump pump wouldn’t help (“we would be placing it into the water table and it would run 24/7!”)  I plugged the drains with expansion test plugs and the basement was dry during the last heavy rain, except for the water coming in from the dry well (which my portable sump pump took care of).

Can I really seal up the dry well?  Will this not cause any damage to my home from the pressure of the water building up in the dry well or under the basement?

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  1. plumb_bob | | #1

    With dry well do you mean sump? A hole dug below the grade of your basement floor?

    If there is water present in the soils that surround your basement, having a way of getting rid of this water is critical. There are different ways of doing this but the basic theory is you have a space for the water to enter and you then drain or pump it away. The typical way to do this is with external foundation drains, or it can be a sump external or internal to your house.

    There is a difference between waterproofing your foundation and dampproofing your foundation. If your basement is truly within the water table then your basement should be waterproofed, which is a much more robust system than damproofing.

    Does your house have foundation drains? Are you in an area with a municipal storm system? Is your house situated so you could drain your foundation to daylight?

    1. jenniferz5 | | #3

      Here is my previous post, which should answer most of these questions:

  2. walta100 | | #2

    From previous questions I believe the basement drains are connected to a dry well in the back yard.
    Before you stop up the drains look at your grading around the dry well and try diverting water away from the drywell if possible.


    1. jenniferz5 | | #4

      Hi Walta,

      I have no idea where the dry well *is* or *goes* - the square hole in my basement (that two professionals have said is the dry well - see the photo in my previous post) backs up to one cinderblock wall (above which is an old outdoor porch, at one point fully enclosed, currently my kitchen) and is adjacent to another cinderblock wall to the exterior of my home (above which is my E-facing patio and a raised landing to the back door). About 10' due East is the drain field for my septic tank. Is there any way to locate the dry well?

  3. walta100 | | #5

    You could have the pipe inspected with a camera, request they mark the location on the surface with a note about the depth of the pipe for $100-300. This should lead you to the drywell.

    Does it seem possible that you have a location on your property to drain this water to daylight?

    I would want to keep a working drain if at all possible by fixing the drywell or redirecting the drain pipe to daylight.


    1. jenniferz5 | | #6

      Walta to my rescue, as usual! Thank you. I, too, would like to keep a drain "just in case," and it would be ideal to give the dry well a drain to daylight. I will call the plumber again.

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