Subsurface (tile) Drainage helps farming operations in many ways. From earlier planting because soils warm-up and dry faster in the spring to increased root growth due to adequately drained soils. The practice of subsurface drainage has been around for many years. Although it was mainly used in low areas that were hard to farm, it is now known to increase crop yields in almost all soil types. Typical subsurface drainage systems are now placed at 50’ to 60’ spacings to increase crop production. This system is commonly known as pattern tiling.