Feasibility Study Summary: Upper Beles Irrigation and Drainage Scheme
This document represents Volume 5 (Soils, Land Use & Suitability) of the feasibility study for the Upper Beles Irrigation and Drainage Scheme, part of the larger Ethiopian Nile Irrigation and Drainage Project financed by the World Bank.
Project Overview
The Ethiopian Nile Irrigation and Drainage Project aims to develop about 80,000 hectares of net irrigation and drainage schemes. The Upper Beles Irrigation and Drainage Scheme is one component of this larger initiative.
Document Structure
The complete feasibility report is organized into 12 volumes covering various aspects:
- Volume 1: Main Report
- Volumes 2-3: Water Resources and Irrigation Development
- Volumes 4-5: Soils, Land Use & Suitability (this document)
- Volume 6: Land Resources & Agricultural Development
- Volumes 7-8: Resource Users & Socio-Economics
- Volumes 9-11: Engineering Surveys, Investigations, Planning & Design
- Volume 12: Environmental Status, Financial Analysis, and Stakeholder Consultations
Soil Profile Analysis
The document contains detailed soil profile descriptions and analyses for 37 locations in the Upper Beles area. Key findings include:
| Soil Type | FAO-WRB Classification | Key Characteristics | Typical Land Use |
|---|---|---|---|
| R1 | Hyponitic Luvisol (Rhodic) | Dark reddish brown clay, well drained, rapid permeability | Rainfed farming (millet, sesame) |
| VH1 | Haptic Vertisol (Eutric) | Very dark greyish brown clay, moderately drained, cracking clay | Grassland with grazing, some rainfed farming |
| VP1/VP2 | Haptic Vertisol (Pellic, Eutric) | Very dark grey/black clay, slow permeability, cracking | Rainfed farming (sorghum, chickpeas), grassland |
| B | Haptic Cambisol (Eutric) | Dark brown clay, moderately drained | Rainfed farming (maize, groundnuts) |
Key Soil Characteristics
- Texture: Predominantly clay soils (typically 70-90% clay content)
- pH: Generally acidic to neutral (4.5-7.0 in water)
- Drainage: Ranges from well drained (Luvisols) to moderately/imperfectly drained (Vertisols)
- Cracking: Vertisols show significant cracking (30-100mm wide cracks extending 50-150cm deep)
- Organic Carbon: Surface layers typically 1.0-3.9%, decreasing with depth
Land Use Observations
Current land use in the study area includes:
- Rainfed farming of millet, sorghum, maize, sesame, groundnuts, and chickpeas
- Grasslands dominated by Pennisetum purpureum (elephant grass)
- Scattered tree cover with species like Acacia, Ficus, and Terminalia
- Some areas with significant termitaria (mound-building termites)
Methodology
The soil study involved:
- Detailed profile descriptions (37 profiles documented)
- Laboratory analyses of texture, pH, EC, exchangeable cations, CEC, organic carbon, and nutrients
- Classification according to FAO-WRB (2006) system
- Assessment of land use and suitability
Conclusion
This comprehensive soil study provides essential data for planning the irrigation and drainage development in the Upper Beles area. The predominance of clay soils (particularly Vertisols) with variable drainage characteristics will be a key consideration in designing the irrigation infrastructure and selecting appropriate crops.