Which direction should perforations face in a subsoil drain?

In a subsoil drain, perforations should face downward to effectively facilitate drainage. This orientation allows water to flow into the drain pipe from the surrounding soil and groundwater, enabling efficient removal of excess water and preventing potential issues such as flooding or saturation of the soil. Facing the perforations downward helps to ensure that water is drawn in by gravity as it seeps through the soil, thus maximizing the effectiveness of the drainage system.

Additionally, this configuration helps minimize the potential for sediment and debris entering the drain. If the perforations were positioned upward or in other directions, it could impede the gravity flow of water into the pipe, leading to reduced performance of the drainage system. For optimal drainage capacity, downward-facing perforations are essential in subsoil drain design.