Abstract

Irrigation performance assessment is important information to water resources managers, farmers and governments especially in arid and semi-arid areas. Unavoidable time delays in this process cause delays in the decision-making process. Satellite remote sensing provide near-real time data in an objective and unbiased manner. Advance in remote sensing technology and related applications have considerably reduced over reliance on ground data. This research aimed to give a preliminary assessment of irrigation system in the commercial irrigation perimeters of Di in Sourou Valley (Burkina Faso) for the dry growing season. It involved the use of both ground data and data derived from remote sensing. It actually computed the irrigation water requirement by perimeter by using three methods (evapotranspiration maps derived from remote sensing, Hargreaves equation and ETo from pan evaporimeter). The Mapping Evapotranspiration at high Resolution with Internalized Calibration (METRIC) was used together with Landsat images, meteorological data and statistical software (R) to obtain monthly and seasonal evapotranspiration map. Monthly irrigation consumption was directly computed from these maps due to the absence of rain at the given period. The seasonal irrigation efficiency was calculated by comparing the irrigation requirements to the season water withdrawal data. Totally eight perimeters were considered. In conclusion, the METRIC model is good for mapping the evapotranspiration by providing to the high spatial resolution maps useful for water resources management at perimeters scale. Using the evapotranspiration from the model and the ETo from the pan evaporimeter, computed efficiencies are closer than the efficiency calculated using Hargreaves equation.