Small-holder farmers are unable to invest large sum of resources in micro-irrigation systems as their opportunity costs are high. Due to small holdings, the system should be adaptive to suit the small odd size plots, simple to operate and maintain and should be capable of recovering the capital investment within two years at maximum. As such high sophisticated micro-irrigation systems do not meet their needs.
Several NGOs, manufacturers and national research programs have recently attempted to address the needs of small holders by developing and promoting simple assemblies of micro-irrigation components known as “bucket kits” and “drum kits”. They are low pressure systems using pressure from a bucket or oil drum mounted approximately 1.5-2.0 m above field level to deliver water through short laterals (generally 15 m) of commercial drip tape. Another variant is a ‘wagon wheel” system working on same principles with the water drum in the centre of the plot with irrigation laterals radiating out like spoke of wheels.
Initially, emitters were formed by punching small holes in the laterals with a heated needle and covering the holes with baffles formed by the same tube split laterally. The HDPE has now been replaced by LLDPE and micro-tubing is now used instead of punched holes and baffles.
Smaller moveable sprinkler systems suitable for use with 5 hpdiesel or smaller electric pumps have also been used for areas ranging 5-60 ha. In hilly terrain such sprinkler systems can use natural gravity. Pipe networks are installed with hydrant off-takes for each farmer allowing them to connect a hose and sprinkler. These systems require a close cooperation between farmers and as such a culture of cooperatives is essential.
Smallholders Irrigation Development Organization (SISDO) in Kenya with the mission to provide easy financial support to is helping farmers both financially as well as technically in provision of these technologies. India and China have established manufacturing capabilities and are promoting micro-irrigation technologies for small-holders. There is need to share these experiences and learn from successes and failures. Click here to share your experiences on smallholders micro-irrigation technologies.