# French drain question



## Glen_Cove_5511 (Jun 13, 2020)

I'm about to install a french drain in an area where water pools after rain. I'd like to know what's the best method to construct it. I plan on using 4" slit corrugated pipe. Do I put a sock on the pipe or not? Also, what would be the best material to backfill the trench with that would allow grass to grow but also allow water through easily for hopefully years to come? Thanks!


----------



## Ge0rdi3brit (Aug 30, 2018)

I just put one of these in myself a few days ago. I dug a rectangular shaped trench 18" deep and 12" wide. I then laid in a good quality non woven geotextile fabric. Then I put the 4" perforated pipe in, then filled with #5 stone. I leveled out the stone then wrapped the fabric over the top. It essentially looks like a giant burrito. 
When it comes to allowing grass to grow, you ideally need about 6" above the top of your burrito. So 18" trench minus 4" pipe equals 14". 14 - 6 is 8". I had 8" of stone above my pipe. This left 6" for roots to grow. 
I dug the 75' trench by hand over two nights. It sucked, but we just got 2.5" of rain here today and no more standing water or swampy grass in that area.


----------



## Glen_Cove_5511 (Jun 13, 2020)

@Ge0rdi3brit Thanks for the reply. I have around 125' to do so I'm going to rent a trencher instead of attempting to dig it by hand. I really like your design of making a "burrito" for the pipe, What kind of soil did you put on top? I'll be treching in clay and I don't want to use it on top since I believe it'll just become compacted and not allow the water through very well. I'm thinking of some sort of loamy topsoil with maybe some garden soil mix added to it. Thanks again.


----------



## Ge0rdi3brit (Aug 30, 2018)

Sorry for the delayed response. We have clay here too. I like your idea of topsoil and garden soil mix. I would mix those together with some clay, however. You want to use native soil as much as possible. 
If you're worried about drainage you could put a couple inlet grates at the grass level, with stone underneath to allow water to really drain in certain areas.


----------



## Glen_Cove_5511 (Jun 13, 2020)

Thanks @Ge0rdi3brit! Inlet grates are a really good idea. I'm also looking at those EZ-Drain products that have the 4" pipe pre-wrapped with foam peanuts and a sleeve. They're pricey but a lot less labor to install.


----------



## Glen_Cove_5511 (Jun 13, 2020)

Have any of you used the NDS EZ-Drain product? I would like to know your thoughts.


----------

