French drains have perforated hollow pipes along the bottom of a trench to quickly vent water that seeps down through the upper gravel or rock, we also wrap the gravel with a filter fabric so your soil doesn't mix with the gravel clogging it up later. French drains are added to landscapes to prevent saturated surfaces and soil. French drains are also used around houses and basements to prevent penetrating or damaging foundations. One advantage of this type is that the drainage pipe is protected from grass and tree roots as well as the soil. We also put french drains behind retaining walls to help relieve pressure when you get a certain height, we call this letting the wall "Breathe". In Tulsa, Jenks, Bixby, Broken Arrow, Sand Springs, Owasso, Tulsa OK and surrounding areas.