The French drain is affected by several factors, such as the type of drain: sandstone, concrete, agricultural drain, or PVC drain. It is also affected by the type of soil: silty, sandy, or clayey. The role of the French drain is to capture groundwater before it exceeds the basement slab and direct it to the municipal pipe. To check the condition of the drain, excavation must be carried out. The next step is to install the chimneys which will allow you to inspect them for cleaning. If the drain is too old, this step may not always be possible.