Old 05-08-19, 10:09 AM
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The place I bought last year has large areas, mostly in the back yard, that consists of clay soil and won't drain. I though of installing a couple of french drains, but I'm wondering if that will solve my problem?... I mean if there's clay all around, it's not going to permeate into the drain. I'm thinking that I may need to till large amounts of loam to mix with the clay??? Ideas?
Old 05-08-19, 10:35 AM
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If your ground is truly clay it won't drain and a French drain won't help much. Clay is almost impervious to water. It's used to line ponds and dams to hold water back.

You can do surface drainage or contour/re-grade the area so water runs off. If you do till in new material you really need to get down to a soil layer that will accept water. Otherwise you're creating a sponge sitting on top of the impervious clay and the only way for it to dry out is through evaporation.
Old 05-09-19, 07:16 AM
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Are you on a well ? If so, the well driller's log should show how deep is your layer of clay. For us it is 5 feet of red clay and then 25 feet of granite....

Do you have a crawl space or sub basement below grade ? Enough rain over a long time can saturate the clay to the extent it will move under and sideways a bit and under your foundation ....and up into your crawl space. I see water in our crawl space once a year. Per #2 post, you should regrade. We can't.... due to concrete walkways and patio.
Old 05-09-19, 09:56 PM
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Dang, I wish you could take half of it and dump it in my yard and then take half the sand that is my soil.
Old 05-10-19, 02:12 AM
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SS, I know what you mean - I have 16 acres of slate rock with very little top soil. The dirt in my yard is only a couple of inches deep. Some farmers around here will till in a load of slate into their clay to improve it.

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