Land Suitability Mapping for Surface Irrigation Using GIS-Based Multicriteria Evaluation Techniques in the Andassa Watershed, Abay Basin, Ethiopia

Irrigation agriculture plays a valuable role in upholding sustainable food security by enhancing agricultural production. Uneven distribution and shortage of rainfall has resulted in unsustainable food production, leading to food insecurity in EthiopiaEthiopia. The establishment of irrigation development strategies may have a significant role in reducing the risk posed by uneven distribution of rainfall. This study aims to map suitable land for surface irrigation development in the Abay Basin of the Andassa watershed, Ethiopia, based on a GIS-based multicriteria evaluation (MCE) technique. Biophysical factors (land use and land cover, soil, slope, and river proximity) that significantly affect surface irrigation suitability were considered. Each of these was processed and analyzed for its potential contribution to surface irrigation suitability on a pixel-by-pixel basis. The factors were weighted using a pairwise comparison matrix, and weights were combined using weighted overlay analysis. The analysis results indicated that approximately 60% of the watershed land was highly (9%) and moderately (51%) suitable for surface irrigation. Slope and river proximity were the major limiting factors during the suitability assessment. Of the 60% of suitable land, 70% could be irrigated with the water resourceWater resources potential of the Andassa River. The remaining 30% of the area needs other means of water harvesting techniques. Future works need to consider soil chemical properties as a determining factor for surface irrigation suitability since this study did not consider these properties as a factor in the overlay analysis.