Low Cost Constant – Head Drip Irrigation Emitter for Climate Change Adaptation in Nigeria: Engineering Design and Calibration
A low cost constant – head emitter for drip irrigation was developed using cheap and readily available materials as a substitute for the imported drip emitters which deter the adoption of drip irrigation in sub – Saharan Africa (SSA). The emitter was calibrated at both laboratory scale and on the field. The drip system comprises of abarrel, sub-main line, lateral lines, tubes and emitters, it can irrigate140 crop stands and can be extended to 560 stands. The emitters produced a mean discharge and emission uniformity (Eu) of 1.60l/hr. and 74 % respectively; while the calibrated manufacturer’s coefficient of variation and distribution uniformity of discharge were 0.098 and 86.3% respectively. The system operates under low pressure (87.9 mbar) and can deliver the daily crop water requirement of a crop like maize in 20 minutes; the overall system performance based on field calibration is generally satisfactory and show potential for improvement when compared with global standards for drip systems. The system’s low cost of N15, 870 ($79) gives it an edge over existing locally developed drip systems, the low technology and the use of locally available materials coupled with the water savings will enable famers to adapt to the impact of climate change in sub-Saharan Africa through the production of high value crops in the dry season.