Surface drainage

Surface drainage refers to the removal of excess surface water through the use of land slope utilizing drainage channels/systems to take away the surplus water from the field. This is normally accomplished by shallow ditches, also called open drains. Surface drainage can be done in five ways:

Random system: Small scattered depression are connected by drains to one another and conveyed to the outlet
Parallel system or field ditch: Fields can be graded for discharge into lateral drains bordering the field. Lateral drains are connected to the main drain
Parallel open ditch system: It is resembling a parallel system excepting the drains which are replaced by open ditches
Bedding system: Parallel beds are developed by shaping and smoothing the land surface so that the run-off drain laterally from the beds to dead furrows
Interception system: Series of shallow open drains across the slope with a mild grade to intercept and remove surface runoff