Analysis of Water Use Efficiency in Smallholder Irrigation Schemes in Kano State

This study analyses water use efficiency in smallholder irrigation schemes operating along the Kano River Irrigation Project area in Kano State, North West Nigeria. Water is an increasingly scarce resource in northern Nigeria, and improving irrigation water use efficiency is essential for sustaining agricultural production in the face of declining rainfall and growing competition for water among farming, urban, and industrial users. This study adopts a field measurement approach, collecting data from 18 smallholder irrigated plots in Bunkure, Kura, and Garun Mallam local government areas during one dry season. Water application volumes are measured using sharp-crested weirs installed at plot inlets, while crop evapotranspiration is estimated using the FAO Penman-Monteith method applied to weather station data. Water use efficiency indicators computed include field application efficiency, conveyance efficiency, and crop water productivity. Findings reveal that field application efficiency averages 61 percent across sampled plots, with significant losses attributed to over-irrigation, field preparation inefficiency, and canal seepage. Crop water productivity for onion production averages 8.2 kilograms per cubic metre of water applied, below best practice benchmarks. Deficit irrigation practices are absent across all sampled plots. The study concludes that water use efficiency in Kano smallholder irrigation is significantly below potential. It recommends adoption of deficit irrigation scheduling, field levelling support, and water user association governance strengthening to improve water productivity.

Keywords: water use efficiency, irrigation, smallholder, Kano State, crop water productivity.