Abstract:
Rainwater harvesting is one solution for agricultural production in water stressed agro-ecological zones. However rainwater harvesting is practical in locations where adequate systems to collect and store rainwater are available. Smallholder farmers in Kenya find the cost of harvesting and storing rainwater prohibitive. The study was conducted in Isinya Sub County Kenya, to promote sustainability of dry land irrigation agriculture by assessing the amount of rainwater harvested from greenhouse rooftop and the costs of storage in a dugout ditch. Three greenhouses were purposively selected. Gutters and pipes were installed to collect rainwater and conveyed to a ditch from where daily water levels were measured for six months. Daily rainfall data were recorded using rain gauges set on the experiment site. All the data were analyzed using descriptive statistical analysis packages. The results showed that average volume harvested from 1m2 surface area of rooftop raining 1mm of rainfall was 0.00075m3. It costed an average Kenya shillings 972 to store 1m3 of water in a dugout ditch compared to using plastic tanks whose average cost was Kenya shillings 7900 per 1m3. Rainwater harvesting and storage from greenhouse rooftops is a viable venture. Further research is needed on the potential offered by rooftops to harvest rainwater for agricultural production in water stressed agro-ecological zones. |
