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Craig D Peltier
03-19-2008, 11:25 AM
Hi anyone know where I can post a question about a drainage issue.

I have asked here before about french drains. I installed on ebut it didint seem to work. I didi find out if you dig down 12 inches its clay so water is just sitting on top.
So if theres any suggestions here great. Area is about 8x15. One way I think it would work but alot of hand work is to dig it all out to 3 feet deep and replace with dirt only and the drain.
Now I think the water just sits on the first few inches and cant soak in.

Thanks

Kim Dressler
03-19-2008, 11:34 AM
Do you have stone at the bottom of your drain. We have really hard clay here and when my hubby put in drains for our spouting he dug down about 3 feet deeper than what he needed and put 3 foot of stone in and then the pipe on top of the stone. it seems to work really well.

Greg Cole
03-19-2008, 12:00 PM
Craig,
Where is the water coming from? Roof run off, driveway runoff etc? Might be able to redirect the water and not have to break the back digging into clay.
Did you make a "sump pit" for the french drain to discharge the water into? Digging the ditch and filling with gravel etc will only make the water settle in the ditch per say.
Were I you, I'd rent a walk behind ditch witch trencher style machine for 1/2 a day and cut the ditch nice n deep & use coarse stone on the bottom & cover with smaller size gravel-pea stone. Install the pipe and sock and fill with more small pea gravel and back fill the ditch with something other than clay to allow the water to perk down into the "sump pit".

Greg

Joe Chritz
03-19-2008, 12:02 PM
I made a living doing landscape for a while so I have a little knowledge of it.

The problem is most likely either saturation or the clay layer. Water won't run through the clay so if the top layer won't allow the water to drain away well enough it will back up. If you have a french drain deep enough it will work, if the soil under is sand or sand/gravel mix and not saturated with water.

Picture a bucket half full of sand with a hole in the bottom. As you pour in water it will fill the sand. Pour slow enough and it drains out and never fills. Pour to much to fast and it will saturate the sand and start to fill the bucket.

If it is all clay you would be better with drains that run to a low area a ways away. That involves digging a trench but it does work. Sometimes if the drainage is poor enough you need a tank, similar to a septic tank to hold rain runoff.

Joe

Craig D Peltier
03-19-2008, 12:12 PM
Do you have stone at the bottom of your drain. We have really hard clay here and when my hubby put in drains for our spouting he dug down about 3 feet deeper than what he needed and put 3 foot of stone in and then the pipe on top of the stone. it seems to work really well.

Theres 2 inch of stone. Then pipe that has landscape fabric over it and then 3 inch of stone then dirt. Still the water on both sides of it is the issue not over the pipe I would think.

Craig D Peltier
03-19-2008, 12:18 PM
Craig,
Where is the water coming from? Roof run off, driveway runoff etc? Might be able to redirect the water and not have to break the back digging into clay.
Did you make a "sump pit" for the french drain to discharge the water into? Digging the ditch and filling with gravel etc will only make the water settle in the ditch per say.
Were I you, I'd rent a walk behind ditch witch trencher style machine for 1/2 a day and cut the ditch nice n deep & use coarse stone on the bottom & cover with smaller size gravel-pea stone. Install the pipe and sock and fill with more small pea gravel and back fill the ditch with something other than clay to allow the water to perk down into the "sump pit".

Greg

Water is coming from the sky.It rains alot here.

There is clay about 6-12 inches down pending where I was along area.It didint seem to go to deep, maybe 12 inches. I dug the whole at an angle. I back filled with very little clay, I tried not to get any back in hole.
I didnt creat a holding area for the water, I made sure it went under a bush and has the end of pipe covered with landscape fabric.

So my proalem is not far enough down? I would think that if the ground has clay under it and all the ground doesnt slope towards drain pipe than it would just sit there and never fall off the cliff of regular dirt into the pipe.No?

Ted Calver
03-19-2008, 12:37 PM
Craig,
If the clay prevents infiltration of the water into the soil it will just sit there. You either need to pipe the water to an outlet at a lower elevation or excavate a trench large enough to hold a normal amount of rainfall and accept flooding when normal is exceeded.
This site will tell you how much volume you have to accomodate, either with a deeper trench or a dry well elsewhere on site. 1" of rain drops 2 bathtubs (10 cu. ft.) full of water on an 8 x 15' area. If nothing else is draining to it that's the volume of water you need to make room for in your trench. http://ga.water.usgs.gov/edu/sc2.html

Craig D Peltier
03-19-2008, 12:55 PM
Craig,
If the clay prevents infiltration of the water into the soil it will just sit there. You either need to pipe the water to an outlet at a lower elevation or excavate a trench large enough to hold a normal amount of rainfall and accept flooding when normal is exceeded.
This site will tell you how much volume you have to accomodate, either with a deeper trench or a dry well elsewhere on site. 1" of rain drops 2 bathtubs (10 cu. ft.) full of water on an 8 x 15' area. If nothing else is draining to it that's the volume of water you need to make room for in your trench. http://ga.water.usgs.gov/edu/sc2.html

Thanks I understand what your telling im pretty sure. I still dont think it answers the question if ground is level and it may not be able to all flow towards the trench then what rains does fall on trench will go away.
I do understand that I need a resevoir, I think I will tap into the house drain an let of flow out to sewer. I dont want to redig it and do this unless I have an understanding if the clayed area that sits on both sides of trench will go away as well.

Craig D Peltier
03-19-2008, 1:05 PM
84418
This is area. Pipe runs shallow from arbor straight to an elbow that turns into closest bush in picture.

84419
Pic of level ground

84420
Bush on left side of pic is where water dumps into. Notice there is a drain there that rund underground to sewer I can tap into.

I dug this up maybe two weekends ago.It hasnt rained much until the past few days.

David G Baker
03-19-2008, 4:16 PM
Craig,
Most areas will not allow you to put ground water into a sewer system. If you have storm drains in your area you can drain or pump your ground water into that.
I agree with what Joe Chritz wrote about how to handle your run off water.

Greg Cole
03-19-2008, 4:58 PM
Most likely your existing french ditch is just not large enough..... which mean you most likely get a do over. Or you get to dig a big sump at the "discharge" end. Coin toss and your call there....
Since it hasn't rained much lately, at least the clay will be easier to dig DAMHIKT. I hate digging clay, especially wet clay...ya have to scrape it off the shovel, scrape it off your boots or they weigh 200 lbs.... just hate it. Not too mention the shovels full of it are 200lbs too. Not like you don't know that after round one...;)
I would really consider renting a trencher versus doing it the "good" old fashoined way. I trenched & laid some conduit last fall with one, about 75 linear feet at 36" depth. The trenching went faster than gluing the pvc conduit and laying it in the ditch. I think it was about $75 for a full day rental here in KC. Just need a trailer to haul it with.... food for thought anyway. The bid from the electrician just for the trench was $750.

Greg

Greg Peterson
03-20-2008, 1:00 PM
The trencher is the way to go. One caveat however. Don't try using a ditch witch when the ground is soggy. I made that mistake. The drive wheels for the ditch witch just sank through the turf into the soil and quickly created a big muddy mess and I ended up doing most of the work. Let things firm up a bit before ditch witching. Summer time probably your best bet.