The irrigation water demand of banana crop (Musa spp.) was estimated and spatialized in the San Francisco River basin, in order to help agricultural project planning and water resource management. Historical data series relative to 81 climatic stations distributed throughout the basin were used. The maximum daily values and the annual total values of the reference evapotranspiration (ETo), crop evapotranspiration (ETc), supplementary demand of the crop and the supplementary irrigation demand (77.2% efficiency) were calculated for each station. According to the results, the in 51% of the basin, maximum daily ETc varied from 6.6 to 7.6 mm d-1, with an annual average of 1,884 mm; the supplementary annual demand of the crop was 1,735 mm, corresponding to 149 mm less than ETc; and the fact that irrigation system operates at 77.2% efficiency instead of 90% implies an increment of 36,688,050 m³ of water per year only in the mesoregion north of Minas Gerais.
water requirements; agricultural project; GIS
