Designing an Irrigation Water Management Plan for Smallholder Rice Farmers Along the Sokoto-Rima River Basin

Efficient irrigation water management is essential for maximising rice productivity along the Sokoto-Rima river irrigation schemes, where poor on-farm water control practices reduce yield, waste water, and increase system maintenance costs. This study designed a water management plan for smallholder rice farms in the Bakolori Irrigation Project area, Zamfara and Sokoto States, North West Nigeria. A professional design methodology was employed, drawing on field surveys of water distribution infrastructure, flow measurement at 30 farm inlets, farmer interviews (n = 60), and review of published rice water requirement data for the Sahel-Sudan transition zone. Current water use efficiency was estimated from supply-demand balance calculations. Results showed that 68 percent of surveyed farms received water application 30 to 50 percent above crop evapotranspiration demand, contributing to waterlogging and nutrient leaching. Water conveyance efficiency from the main canal to farm level was estimated at 58 percent due to unlined tertiary canal losses. The water management plan developed specifies paddy water depth management protocols by growth stage, intermittent irrigation scheduling guidelines to reduce water input by 25 to 35 percent without yield penalty, farmer water users' association operational procedures, and canal maintenance scheduling. Expert review by eight irrigation agronomy specialists confirmed the plan's technical accuracy. The study recommends implementation by the Sokoto-Rima River Basin Development Authority with water users' association capacity building as the primary field delivery mechanism.

Keywords: irrigation water management, rice production, Sokoto-Rima, water use efficiency, smallholder irrigation