This volume gives results of a semi-detailed soil survey carried out over a total gross area of 9,559 ha of the Mogambo irrigation project area. The report aims to extend the results of earlier studies on soils in the area . This is achieved by a more detailed observation network of survey sites in the area in particular within the Juba alluvial sails (five sites/km2). It also provides more quantitative data on the soil chemical and physical properties as an additional aid in soil classification for planning the development of irrigation in the area. Soil units identified are described in terms of modal characteristics and the variation found within the unit with profile descriptions for a11 pits and selected auger holes included in Appendices II and III. The nature of the mapped boundaries is fully described. The land was classified making use of the United States Bureau of Reclamation (USBR) methods, modified to suit the conditions found in the area. Suitability for rice and for field crops other than rice were considered separately and special use Class 4 was used to indicate areas more suitable for sprinkler development. Limitations affecting land suitability are denoted by the use of suitable land class suffix letters.