Amibara Irrigation Project II - Drainage & Salinity Study
Document: Volume 2 - Annexes & Maps
Prepared for: Government of Ethiopia, Water Resources Development Authority
Consultant: Sir William Halcrow & Partners
Date: April 1982
Key Findings
- Comprehensive study of drainage and salinity issues in the Amibara Irrigation Project area
- Includes soil profiles, observation well records, and chemical analysis data
- Focuses on Melka Sadi Farm and Amibara areas
- Provides recommendations for field drainage solutions
Main Components
1. Observation Well Records
Detailed measurements from multiple wells showing:
- Water table depth fluctuations
- Electrical Conductivity (EC) measurements indicating salinity levels
- Data collected from August 1980 through November 1981
2. Soil Profile Descriptions
Detailed descriptions of 54 soil pits/bores including:
| Profile No. | Location | Key Characteristics |
|---|---|---|
| 1-20 | Various AIP locations | Alluvial soils, flood plain characteristics, drainage conditions |
| 21-54 | Banana plantations and abandoned areas | Salinity issues, texture variations, water table effects |
3. Soil Chemical Analysis
Laboratory results showing:
- pH levels of saturated extracts
- Electrical conductivity measurements
- Soluble cation and anion concentrations
- Exchangeable cations and cation exchange capacity
4. Local Rainfall Variation
Analysis showing significant spatial variation in rainfall:
- Comparison between Melka Warer Research Station and Amibara Settlement Area
- Examples of 44-69% differences in rainfall amounts between nearby stations
- Important implications for irrigation planning
Conclusions
The study provides a comprehensive baseline of soil and water conditions in the irrigation project area, with particular attention to salinity issues that affect agricultural productivity. The detailed profiles and monitoring data support the development of appropriate drainage solutions to manage water tables and salinity levels.
Note: This document is Volume 2 (Annexes & Maps) and should be read in conjunction with the main report volume for complete context and recommendations.