Amibara Irrigation Project II - Drainage & Salinity Study (1982)
Document Overview
This report, prepared by Sir William Halcrow & Partners for the Ethiopian Water Resources Development Authority, focuses on drainage and salinity issues in the Amibara Irrigation Project II area. The document is Volume 2, containing annexes and maps to support the main study.
Key Sections
Observation Well Records (Annex I)
Contains detailed measurements from observation wells including:
- Depth to water table measurements
- Electrical Conductivity (EC) readings (indicator of salinity)
- Data collected from 1980-1981 at multiple locations
Soil Profile Descriptions (Annex II)
Detailed descriptions of 54 soil profiles (DEH 1 - DEH 54) including:
- Location and landform information
- Soil characteristics (texture, color, structure)
- Drainage conditions
- Water table depths
- Salinity observations
- Vegetation/land use
Soil Chemical Analysis (Annex III)
Laboratory results showing:
- pH levels
- Electrical conductivity
- Soluble cation/anion concentrations
- Exchangeable cations
- Cation Exchange Capacity (CEC)
Localized Rainfall Variation (Annex IV)
Comparison of rainfall data between stations showing:
- Significant spatial variation in precipitation
- Examples where one station received 44-69% more rain than another just 6km away
- Daily rainfall records showing some stations had double the rainfall of others
Key Findings
- Detailed characterization of soil types and salinity conditions in the irrigation project area
- Evidence of significant salinity issues affecting agricultural productivity
- Observation well data shows variability in water table depth and salinity
- Rainfall patterns show high spatial variability across the project area
- Soil profiles reveal stratified alluvial deposits with varying drainage characteristics