Sub Surface Irrigation | Subsurface Irrigation Working | Advantages

Introduction Sub Surface Irrigation

In sub surface Irrigation , effluent is delivered directly to the infiltrative surface of the soil using specially manufactured polyethylene tubing with built-in turbulent flow emitters.

  • Subsurface irrigation is a highly-efficient watering technique.
  • It reduces outdoor water use by 30 to 40 percent.
Sub Surface Irrigation
Sub Surface Irrigation

Design of Sub-surface Irrigation

  • It consist a masonry chamber (Distribution box) where the effluent of septic tank uniformly distributed an undergroundnetwork.
  • Emitter lines placed on 2 foot centers with a 2 foot emitter spacing such that each emitter supplies a 4 sq. ft area.
  • These lines are placed at depths of 6-10 inches below the surface.
  • Absorption trench 30 to 90cm wide filled with gravel(15cm thick) layer and well graded aggregate(15cm thick layer).
Sub Surface Irrigation System
Sub Surface Irrigation System


  • Septic tank effluent is allowed to enter into a masonry chamber (distribution chamber).
  • from where it is uniformly distributed an underground network of open jointed pipe ,into absorption trench called dispersion trenches .
  • The suspended organic matter present in the effluent will be absorbed in the absorption trenches.
  • The clearer water seeping down to the water-table may come up to the plant roots throughly capillarity, thus fulfilling their irrigation water
Sub surface irrigation
Sub surface irrigation

Advantages of Subsurface Irrigation

  • Health risks are minimized.
  • The system is easily automated.
  • Consumption of nitrates by the plant material is increased.
  • The systems are durable and have a long life.
  • Disposal of water by means of evapotranspiration by the plants is maximized