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Ben I
09-06-2011, 11:05 PM
I'm in the process of installing a drain. It's going behind a house to catch surface water coming down the hill towards the house and drive. I'm planning on a 24"x24" trench filled with filter rock and no pipe. The trench will be 100'-125' in length and has a natural fall to it all ready. about 1/3 of the trench will be dressed with 3/4 inch river rock on top of the filter rock at grade level because it is the walkway from drive to back porch. The other 2/3's is going to be underneath the drive so will be dressed with #57 or crusherrun at grade level. My question is will this work and drain the water off properly or should I consider doppin in some drain pipe?

Dr.NewEarth
09-06-2011, 11:32 PM
I would drop in the pvc.
Our landscape standard here wants us to lay landscape fabric in the trench, lay about 4 inches of 3/4 crush in the bottom of the hole, .........
then lay out the pvc (with the holes facing down haha) and then a few more inches of crush around and on top of the pvc. Then the landscape fabric is wrapped around the whole thing.

This prevents fine particles of soil from plugging up the crush and makes the thing last longer.

Like I said, this is how the Landscape Association members and the Landscape Architects here spec a project. We use the B.C. Landscape Standard and then from the plans to the finished product, we are using the same specs.

Now, ten other people will tell you that I'm wrong.

Ben I
09-07-2011, 09:00 AM
Thanks for the input! I've been told both so I wanted to get some different opinions. BTW this project is at me house. . not for a client but I'd still rather not have to dig it up twice. Again thanks for the advice.

DIXIECONTRACTING
09-08-2011, 10:20 AM
I would drop in 4" perforated corrugated pipe that way for sure the water will run.

Dr.NewEarth
09-08-2011, 10:43 AM
This is for people in B.C., or just general information but...

We aren't supposed to use the "big O" corrugated drainage pipe here any more.
The governing body changed the building code a few years ago.
We can use pvc
So, that makes projects a bit more expensive.

LindblomRJ
09-08-2011, 09:00 PM
Some sort of 4" pipe with holes in it will work. Corrugated or 4" PVC is a great idea to carrying the water away.

Ben I
09-08-2011, 09:15 PM
I was afraid to use corrugated because it will be under my driveway. . . afraid it might callapse over time

Dr.NewEarth
09-09-2011, 12:55 AM
That's why it's forbiden in our building code now.

DIXIECONTRACTING
09-09-2011, 07:06 AM
PVC definitely the way to go under a driveway. I have never had a corrugated collapse while in the yard areas or beds but I always use PVC if going to be driven over.

esenterprise
09-12-2011, 03:57 PM
A french drain with no pipe in it is the original french drain. Ive never installed a french drain without the pipe but it should work!

Kiril
09-12-2011, 04:38 PM
I'm in the process of installing a drain. It's going behind a house to catch surface water coming down the hill towards the house and drive. I'm planning on a 24"x24" trench filled with filter rock and no pipe. The trench will be 100'-125' in length and has a natural fall to it all ready. about 1/3 of the trench will be dressed with 3/4 inch river rock on top of the filter rock at grade level because it is the walkway from drive to back porch. The other 2/3's is going to be underneath the drive so will be dressed with #57 or crusherrun at grade level. My question is will this work and drain the water off properly or should I consider doppin in some drain pipe?

Proper design of an effective intercept drain is a bit more involved than simply throwing some rock in the ground, with or without pipe, wrapped or not wrapped. Either design it correctly before you start the install, or just forget the whole thing because it will just end up being a complete failure and waste of money. To this point no one has offered up any of the information you really need to design this properly .... for example how to properly size your pipe. I suggest you sub it out and stick to what you are good at doing.