Irrigation Suitability of Cheffa Valley Water Resources at Oromiya Special Zone in Ethiopia

To achieve sustainable irrigated agriculture in potential areas of the country better understanding of the extent, type and distribution of soluble salts are decisive for effective control of soil salinity and sodicity problems. In line with this, this study was conducted in Kemissie district, Oromiya Zone of Amhara Regional State in Cheffa Valley of North Ethiopia. This study focused on irrigation water characterisation and classification at Cheffa Valley concerning salinity and sodicity. Underground water samples from five profiles excavated on representative locations in different land use and two irrigation water samples from Borkena River were collected and analysed. The underground water samples were moderately alkaline in reaction and highly saline in salt content while the Borkena River water samples were mildly alkaline in reaction and moderate in salt content. The Cl- and HCO3- salts of Na+ and Ca2+ ions are mainly contributing salinity and sodicity hazard in both underground and River water samples.Underground waters were high in soluble salt content, medium in sodicity and safe in residual sodium carbonate hazard while Borkena river is medium insoluble salt content, low in sodicity and safe in residual sodium carbonate hazard. Accordingly, the current result revealed that Borkena River is potentially suitable for irrigation purpose while utilisation of underground waters for irrigation without treatment is aggravated salinity problem. Therefore, unless proper management practices were applied Soils of the area were prone to secondary salinisation.