French Drain Installation -- French Drains are designed to do a lot of things. If you have an area that has unwanted water standing in it or running across it, a French Drain can be the answer. A French Drain is a trench that runs across the Drainage Problem Area. A French Drain Pipe is placed in the bottom of the trench. The French Drain Pipe is perforated with thousands of small holes. In most cases the Drain Pipe has a nylon soc around the pipe to act as a filter for the French Drain. The French Drain trench is then filled with some type of small rock or stone. CMG typically uses crushed 1 inch Lime Stone to cover the French Drain Pipe. The dirt that was dug out of the trench is taken away or spread out around the French Drain. The Lime Stone replaces the dirt and fills the French Drain Trench all the way to the surface.
When water come in contact with the French Drain, it seeps down through the stones and into the French Drain Pipe. It then flows through the Drain Pipe to the exit point. Typically a French Drain will have two possible exit points. The First is called a "Pop-Up Emitter." It is a Green Lid on top of a release basin for the French Drain.
The second type of Exit Point for a French Drain is a "Curb Fitting." The Curb Fitting is installed through the curb going out into the street. The French Drain Pipe runs to the Curb. The curb is cut out and the Curb Fitting is cemented through the Curb.
French Drains are designed to move large amounts of water. A French Drain moves water away from the Drainage Problem area from the Surface like a large Surface Drain, But also below ground, or sub surface. Most people don't take into account the water that flows to a problem area underground. Sub surface water flow is not eliminated by a Surface Drain. A French Drain can move away water that is below the surface of the ground and drain away water that is on the surface.
We just finished a 4 inch Drainage System in Yukon. It was a complicated system to install. It utilized 4 inch French Drain in the flower beds, 12 inch Surface Drains on the side of the house, 6 inch French Drain along the garage foundation with 2 Pop - Up Emitters in the back yard and 3 Curb Fittings in the front. First we installed 4 inch French Drain in the flowerbeds on both sides of the front door. We connected 4 inch solid Drain Pipe into the French Drain and ran them underside walk to the curb. Next we cut the curb with a concrete saw and installed 3 curb outlets for 3 separate French Drains.
Next we installed 4 12 Inch Drain Basins with grates along both sides of the house continuing with Solid Drain Pipe to the Pop-Up Emitters on the back fence. Finally we completed the Drainage System by installing a long run of 6 inch French Drain down the side of the garage foundation. Installing the French Drains in the flower beds was the most difficult and took the most time. Each French Drain took over a ton of crushed limestone to fill the French Drain trench. The Six inch French Drain took even more limestone.