French drains

[DVerbarg]

Need some ideas for a problem. Built a new house this past year and still have a few items to finish (well, maybe a few more than a few /w3tcompact/icons/blush.gif). A couple months ago we had a stamped concrete sidewalk poured. At the last minute my wife remembered that we intended to install a french drain for the gutters which would go under the sidewalk and across the yard. She had the concrete guys call me at work and I told them where it was supposed to go, they dug the trench laid the pipe, poured the sidewalk (sidewalk turned out great until UPS drove over the end of it and cracked a corner off of it a few days after pouring /w3tcompact/icons/frown.gif).

The issue now facing me is: I intended to use 4in Sch40 PVC for the drains, the concrete guys put the flimsy black corrugated under the sidewalk and up to the house. I like the smooth PVC as opposed to the rough corrugated because of the ease of flushing and cleaning debris out of the drain not to mention the strength to resist crushing when driving the tractor across the yard. This particular drain line will be over 140 ft in length. Should I try to "drive" the PVC through the corrugated to replace it, or am I just being too **** about this and just live with the corrugated? Live with the corrugated under the sidewalk but use PVC immediately after for the rest of the run? The corrugated is in a straight line under the sidewalk. Thought I might try to use the FEL to push the pipe through and cut off each end (assuming that each end would be damaged during the "drive").

What would you do? Leave it? Change it? If so, how?

DaveV

 

[AndyR]

Dave,
I would leave the corrugated under the walk. If it ain't broke... But I see no harm in heavier pipe the rest of the way if it is going to be shallow (under 2 feet). If you are going deeper you can find good non-Sch.40 PVC at a much better price and it should be fine. I fully agree about the smooth pipe being easier to maintain.

 

[JJT]

Dave, I use a pipe called N12, (ADS product), for all my underground drainage. It's corragated outside and smooth wall inside. It has a 9K crush, and I'd put it up against sched 40 any day. Another advantage - it will couple with the corragated drain pipe you have under your side walk. I'd replace all the existing pipe except the short 3 - 4 ft run uinder the side walk. The pipe is cheap when you think about the labor, (do the job once!). Check out, http://www.ads-pipe.com/ JJT

 

[gerard]

ditto to leaving the pipe under the walk alone. I've laid the corrugated stuff for both sump pump and rain gutters at two of my houses now, used several hundred feet all told and never had a problem. The little corrugations may eventually fill in with fines but all that does is make the pipe smooth wall and the water flows just fine. The important part is to not let garbage/leaves etc into the pip in the first place. I found the best way to do that is excavate a small dry well where the downspout enters the ground, lay the drain tile and cover with a course gravel. The gravel acts as a filter and keeps leaves etc out of the drain tile. Many people like to run the downspout right into the pipe but if you do that you need to either have a screen on the top of the gutters or clean out the pipes once in awhile. As far as crush if you have at least 6-10 inches of cover on top of the pipe and you give the ground time to settle and pack after backfilling you can drive a car over it and you won't hurt anything. Once covered all the way around it's really pretty strong. If you have the ground pitch and can bury deeper thats just "icing on the cake"!! /w3tcompact/icons/smile.gif