Abstract

This paper assesses the groundwater yield potential for irrigation purposes in a semi-arid region of Potiskum, Nigeria where millet and sorghum were selected for the study. The study utilized Food and Agriculture Organization irrigation water resources management tool (CROPWAT 8.0) to estimate the reference evapotranspiration (ETo) and irrigation requirement. The ETo was further subjected to time series analysis to reveal the trend within the series using Mann-Kendall and Sen’s Slope estimate. The yield of 80 existing boreholes was estimated and compared with the irrigation requirement. The results of the study show that the ETo of the area varies between 3.92 mm/day and 7.25 mm/day with an average ETo of 6.68 mm/day. The time series analysis reveals an increasing trend in most of the months with an annual increasing trend at 0.007 mm/year. An increasing trend was also revealed in three seasons. The monthly irrigation requirement varies between 0.09 l/s/ha and 0.781 l/s/ha whereas the average yield of the boreholes in the area was found to be 1.18 l/s/ha. The study concludes that there is an appreciable yield of groundwater to support irrigation in the area and recommended for comprehensive study into the possibility of conjunctive use of surface and groundwater sources for sustainable irrigation practice.

Key words: CROPWAT 8.0, Evapotranspiration, Groundwater, Irrigation, Sustainable Development Goals