French drain systems are a collection of patented basement waterproofing products which are used together to hinder ground and surface water from penetrating and damaging a building's foundation. This keeps the basement dry.
During wet weather, precipitation saturates the soil outside the foundation. A high hydrostatic pressure difference is eventually created between the basement and the foundation exterior. This pressure difference is enough to allow water to flood a basement even if only a small leak exists. French drain systems lower the hydrostatic pressure by providing ground water with an escape route through perforated pipes surrounded by gravel. The water is then directed to a downhill slope, dry well or rain garden where the extra water is absorbed by plants. This system is essential in areas where a city water system or other wastewater areas cannot be used.