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.
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).
Working
- 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
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