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Uganda Atlas of Our Changing Environment - GRID-Arendal

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Rainy season: Kooki hills in the background overlooking Lake Kijanebarola, Rakai District (NEMA 2008)<br />

Origin <strong>of</strong> Lake Kijanebarola and River Rwizi-Kibare-Bukora system<br />

During the formation <strong>of</strong> the Western Rift valley system,<br />

landscape was tilted eastwards which led to rivers and<br />

streams being reversed to flow through new routes<br />

on a down warped landscape and drowned valleys.<br />

Consequently, a fairly long river system <strong>of</strong> Rwizi-Kibare-<br />

Bukora developed. The system originates from its<br />

uppermost catchment in the south-western highlands <strong>of</strong><br />

Itojo, Rwampara, and Buhweju in Ntungamo, Mbarara and<br />

Bushenyi districts, respectively. Due to the down warping<br />

effects, depressions were formed along its course, which<br />

were filled with water both from the river flow and from<br />

micro-catchments to form lakes Kacheera, Mburo and<br />

Kijanebarola. On its long course from the highlands to<br />

Lake Victoria, the river flows out <strong>of</strong> lakes, Kacheera and<br />

Mburo, through Kanagisa wetlands - a poorly defined<br />

valley system with numerous shallow depressions choked<br />

by wetlands; and then into Kijanebalola, a rather streak<br />

valley that was filled by water from the river and flanking<br />

cathments to form the lake. From Lake Kejanebarola, the<br />

system changes into Kibare-Bukora Rivers, which drain<br />

the Kooki hills through the Sango Bay plains, and then into<br />

Lake Victoria via the western shores.<br />

The Lake Kijanebalola feature is itself a recent formation,<br />

which is a result <strong>of</strong> drowning <strong>of</strong> part <strong>of</strong> Rwizi-Kibare river<br />

course. It is a very shallow lake with an average depth <strong>of</strong><br />

84<br />

5 m; and occupies a wide and streak valley, covering a<br />

surface area <strong>of</strong> 35 km 2 and with a circumference <strong>of</strong> about<br />

88 km. The name <strong>of</strong> the lake itself implies that it was<br />

formed when people were there seeing. Although the age<br />

<strong>of</strong> the lake is not readily known, it is a recent formation<br />

and could be traced and estimated through both scientific<br />

and folklore means.<br />

The water catchments <strong>of</strong> the rivers and lakes are<br />

experiencing heavy population pressures, which become<br />

the key driver <strong>of</strong> environmental change in the area. Due<br />

to population pressure, land degradation has increased<br />

to unprecedented magnitudes, especially through loss <strong>of</strong><br />

vegetation cover and soil erosion. This is thought to have<br />

reduced the hydrological potential <strong>of</strong> the catchments and<br />

consequently the volumes <strong>of</strong> water flowing through the<br />

river to the lakes. In addition, heavy silting <strong>of</strong> the river<br />

valleys and the lakes has the effect <strong>of</strong> reduced the water<br />

holding capacity <strong>of</strong> these water systems; and worse still,<br />

the shallow nature <strong>of</strong> the lakes and the high potential<br />

evaporation rates in the area may augment the problem.<br />

<strong>Environment</strong>al change<br />

Of recent both the river system and the lakes through<br />

which it drains have experienced heavy silting and<br />

this has affected the water quality to the extent that<br />

Rakai District Local Administration (2007)

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