Irrigation Technology for Smallholders Farmers

Principles of drip irrigation

Drip irrigation involves supplying water to the soil very close to the plants at very low flow rates (0.5-10 liter/hr) from a plastic pipe fitted with outlets (drip emitters). The basic concept underlying the drip irrigation method is to maintain a wet bulb of soil in which plant roots suck water. Only the part of the soil immediately surrounding the plant is wetted. The volume and shape of the wet bulb irrigated by each drip emitter are a function of the characteristics of the soil (texture and hydraulic conductivity) and the discharge rate of the drip emitter. Applications are usually frequent (every 1–3 days) to maintain soil water content in the bulb close to field capacity.

The SMS Irrigation system

Assembly instructions:

1.     Prepare a rectangular area 7.5 wide × 16 m long.

2.     Peg out the position of beds and paths to accommodate 5 beds each 1m wide × 15 m long. Leave a path 20 cm wide between the beds.

3.   Connect the manifold by cutting the pipe into 3 pieces each 1.25 m long.  These are connected to the 3 tees and the 2 bends connected at the ends. The 3 tees and 2 bends on each side of the PVC pipe are designed to be centrally located on the five planting beds. Depending on the location of the drum, a tee is connected to channel the water from the drum to the manifold.

4.     Use PVC glue for leak-proof fitting and wait for the required duration to allow bonding.

5.     Lay out the drip tapes on the beds, two lines per bed, and insert the filter plugs into the open ends of the outlets in the manifold.

6.   Finally, connect one end of the connector tubing to the filter plug and insert the barb fitting to the other end. Connect the drip tube to the drip lock fitting.