Sub surface method of irrigation

In sub surface method of irrigation, water is applied below the ground surface by maintaining an artificial water table at some depth depending upon the soil texture and the depth of the plant roots.

Water reaches the plant roots through open ditches or underline pipelines called tile drains or mole drains. The water application system consists of field supply channels or trenches suitably spaced to cover the field adequately and drainage ditches for the disposal of excess water.

Merits

i) High water use efficiency.

ii) Needs least labour.

iii) Low evaporation loss through ground surface.

Demerits

i) Very expensive

ii) A slight negligence in applying water may lead to water logging in root zone

iii) Water having a high salt contain cannot be used.