Question about dry wells
We are putting a french drain around our basement to collect sub-surface water before it hits basement wall and footing drain. The terrain is such that can’t divert to daylight or storm sewer. We are in Pacific Northwest, so plenty of water to divert. Want to put in a dry well to collect the water from the french drain. I was thinking of a deeper trench/hole filled with washed rock, covered with filter fabric and then soil. I see you can buy plastic/concrete dry wells to stick in ground and fill with rock, is it important to have such a structure to prevent silting of dry well. or is rock and filter fabric alone sufficient?
Thanks,
Dave
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Replies
Dave,
Using a dry well for drainage is always worth a try. It may or may not work.
For the dry well to work for a long period of time, you need to have deep, well-draining soil. In other words, sandy soil, not soil with a lot of clay. The soil needs to be deep and the water table needs to be low.
Even so, dry wells can silt up. Whether or not it silts up slowly or quickly depends on how much silt is in the drain water you send to the dry well.
A consultation with a soil engineer might help.