Abstract:
Currently, there are five reservoirs proposed for irrigation purpose only in Lake
Tana sub basin. These are: Gumera-A, Megech, Ribb, Gilgel Abbay-Band Jema.
Among these Megech, Ribb, Gumera-A and Gilgel Abbay-B are the focus of this
study. At Megech reservoir two alternatives are proposed. The first alternative is
for irrigation only and the second is for irrigation and water supply.
The proposed irrigation area of: Megech of alternative one is 14622 ha, Megech
of alternative two is 7311 ha, Ribb 19925 ha, Gumera 1400 ha and Gilgel Abbay
B 12490 ha.
Integration of hydropower in the proposed reservoir study is analyzed by using
Excel Spreadsheet. A sequential routing technique is used to see options of
hydropower generation. Final output from sequential routing shows the estimated firm power generation
of Gilgel Abbay-B, Megech alternative two, Gumera-A and Megech alternative
one is 5.614 Mw, 0.61 Mw, 0.13 Mw and 35kw respectively without affecting the
irrigable area. But, from the analysis one can see as the irrigable area decreases
the hydropower generation will increase and vice versa because of the rise of
reservoir water level.
