Lawn + Garden Projects
Installing a French Drain


BLACK+DECKER B+D Contributor 189 Projects
A French drain is a very simple, but very effective solution for poorly draining lawn areas. It involves digging a trench for gravel-covered length of pipe that filters runoff from the lawn, leading it to a low-lying area such as a gutter or wooded section of the property. Never direct a French drain or any other drainage improvement to a neighbor’s property.
The most important part of the French drain is the slope. Maintaining a reasonable slope ensures that the runoff will follow the drain. The drain tube itself is covered with permeable landscape fabric. The idea is to allow for water to flow through, while blocking fine soil that could clog up the holes in the drainpipe. Do not use rubber or standard plastic sheeting or pond liners. These will not allow for the free flow of water. You should use clear gravel to surround the pipe for the same reason. Don’t use gravel with fines that could clog or block the holes in the drainpipe.
Your tile should underlie the lowest part of the problem area and slope slightly toward an above-grade exit point. Use a 2 x 4 with a level on top to ensure the trench floor carries a gentle downward slope. The trench needs to be at least 1 inch deep where gravel covers it in the problem area. The tile will exit into the gently sloped swale that will carry the water away.