Micro irrigation
Practical Action
Some initial training is required to show how to get the best results from the system and
careful attention should be taken to a number of common problems that occur with the
system comprising of:
clogging of the trip tapes especially if water is not well filtered. The emitters can be
cleaned by blowing dirt out and then flushing out the particles with clean water.
leakage at connections: this can be checked and corrected
weeding must avoid puncturing the tape
vermin can damage pipes in their search for water
theft of equipment
The bucket kit is the smallest type of drip irrigation available. Although productivity is
increased providing greater food security and improved nutrition, the amount of water and
labour saved is small. Often there is not sufficient surplus produce for users to sell and
provide financial benefits.
Bigger containers can be used to suit larger market gardens. Large customised drum kits
irrigating a high-value crop offer greatest financial impact.
A research project on Affordable Micro Irrigation Technology (AMIT) was conducted by
Intermediate Technology Consultants (ITC) and International Development Enterprises (IDE)
in India and Zimbabwe. The looked at the constraints to adoption of low-cost, improved, drip
irrigation technologies by poor farmers. The findings are available on ITC's website.
In East Africa drip irrigation has been promoted by Practical Action East Africa and the Arid
Land Information Network (ALIN) who sell drip irrigation kits similar to the ones used in India
and Zimbabwe.
Pipe irrigation
The use of buried clay pitchers is an
ancient technique of subsurface irrigation.
The use of clay pipes had been initially
tried in Russia and Mexico. ITDG
Southern Africa along with others in
Zimbabwe developed a low cost variation
of this irrigation method in which clay
pipes were buried beneath vegetable beds
of the 450 women members of garden
groups.
One end of the pipe is blocked and the
other is tilted out of the soil to allow
filling. The pipes were laid end to end
below the soil surface. When the pipe is
filled, water will gradually escape from the
cracks between the pipe sections and
through the pores in the clay to provide a
continuous supply of water to the
vegetables.
There were difficulties in obtaining the
correct dimensions. Research at the
Lowveld Research Station, Zimbabwe
found that the optimum pipe size was
75mm inside diameter and 300mm long.
Figure 3: Water is poured into the pipe which
then irrigates the plants at the roots
©Barbara Bryant/Practical Action
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