Question: How do I install a French drain?

Answer: These are subsurface drainage systems designed to remove excess water from a low area. The process is fairly simple, but you need to do it carefully. It involves trenching one foot under or very near the waterlogged area. Put 1-2 inches of coarse gravel at the bottom of the trench, then an inch of pea gravel. Place 4-inch PVC perforated pipe on top of this gravel. Be sure the pipe has at least 1/4-inch of fall per 10 feet of length from its high end to the low end. Place more gravel up and around the pipe, then sand, then loam garden soil. You’ll need to continue the piping to a spot where it can empty out into a ditch or onto the lawn. As the water seeps into the pipe it will also be carried out away from the bed.

Back To Top