scope:

Purpose

This Engineering Practice is intended to improve the design, construction and maintenance of surface drainage systems which are adapted to modern farm mechanization. It is limited to agricultural or farm-size areas, 259 ha (640 ac) or less, in the humid region of the eastern USA.

Surface drainage is normally required for efficient crop production on slowly permeable soils with restrictive topography. It is not required when excess water is removed naturally. Typical problem areas are glaciated areas, coastal plains, bottomlands, deltas, and old lake beds. Surface drainage may eliminate the need for subsurface drains under certain conditions. Surface drains also apply to farm mains used to collect water from field drains and subsurface drains.