Wolkayite Sugar development project – detailed design of Zarema May Day dam and its appurtenant structures – Ethiopia
Country, Location(s)
Ethiopia
Zarema River basin, North-western Tigray
Client(s)
SGI Studio Galli Ingegneria, Padua – Sembenelli Consulting, Milan
Aims of the Project
To carry out a geological, geomorphological, structural and geo-mechanical study of the area identified as suitable for the realisation of an irrigation system related to a dam along the course of the Zarema River in the province of Tigray.
Contract Holder(s)
Geomap Srl
Staff
2 field geologists, 2 geologists photointerpreters, 1 GIS operator
Project Activities
A first phase of the work involved the pre-processing of very high resolution satellite images (Worldview 2): orthorectification, pan-sharpening, mosaiking and contrast stretching, to produce a support for the photointerpretation and field operations.
Subsequently, the interpretation of the images of the area of the planned Zarema reservoir concerned geology, drainage, landforms and geomorphological processes, i.e. gravity movements and erosion, total field of lineations (faults, fractures, dikes and regional lineaments). At the same time, a first reconnaissance mission was carried out to verify the conditions and the accessibility of the area and to plan the successive survey mission. During this, that was lasting 15 days, a detailed geostructural and geomechanical survey was carried out and the checking the photointerpretation in the area of the foreseen irrigation works.
The collected data were then processed, aiming at the geomechanical characterization of the outcropping lithotypes, also through laboratory analyses (indices of rock mass quality), and at the creation of a large-scale geostructural map of the irrigation work area.
The documents produced were: Report; Drainage map, Geomorphological map, Photogeological map and Map of the total field of lineations for the area of the entire Zarema reservoir, at a scale of 1:10,000 and 1:25,000; detailed geological maps for the area of the irrigation works at the scale of 1:1,000 and 1:5,000; geological cross sections along the proposed lay-outs of irrigation canals and tunnels.
