How To Install A French Drain / Dry Well
A French drain is a trench filled with gravel or rock or containing a perforated pipe that redirects surface water and groundwater away from an your home or area that you choose. A French drain can have perforated hollow pipes along the bottom to quickly vent water that seeps down through the upper gravel or rock.
French drains are primarily used to prevent ground and surface water from penetrating or damaging building foundations. Alternatively, French drains may be used to distribute water, such as a septic drain field at the outlet of a typical septic tank sewage treatment system. French drains are also used behind retaining walls to relieve ground water pressure.