What Is A French Drain?

A French drain is a type of landscaping drain used to direct surface water and groundwater away from buildings and other structures. It consists of a trench filled with gravel or rocks and a perforated pipe that collects and carries water away from the site. French drains are often used to address issues with poor drainage, such as water pooling in low-lying areas, and to prevent water damage to buildings and foundations. The drain should slope downward and away from the structure it is meant to protect, and its outflow should be directed to a safe location where the water can be safely discharged.

The origin of the term "French drain" is widely attributed to Henry French, an American judge and agriculturalist who wrote about the design in a book he published in 1859. French described a trench filled with gravel and a perforated pipe that could be used to collect and divert groundwater away from a building or other structure. The design was simple and effective, and it quickly gained popularity as a solution for improving poor drainage and preventing water damage to buildings. Over time, the design became known as a "French drain" in honor of its inventor, and the term is still used today to describe this type of drain.