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a crucial source of water for the whole subregion,
providing water for domestic, industrial, irrigation
and hydropower uses (UNEP, 2014). In Rwanda,
for example, annual precipitation varies from less
than 700 mm in the lowland areas in the east to over
1,500 mm in the more mountainous areas of the west
(MoNR, 2012). Some of the subregion’s largest cities
depend on mountains for their water supply: Dar es
Salaam gets its water from the Ulguru Mountains
(part of the Eastern Arc Mountains) and Nairobi is
supplied by the Aberdare Mountains (Fisher et al.,
2011; NEMA, 2011). Mount Kenya alone provides
fresh water to about 7 million people (Kohler and
Masseli, 2012).
Key ‘water towers’ in East Africa include the
Albertine Rift, the Kenyan Highlands and the
Ethiopian Highlands. Some water towers, such as the
Albertine Rift and Mount Elgon, are transboundary.
Rivers originating from the mountains cross national
borders; these include the White and the Blue Nile,
which drain into the Nile River. The transboundary
nature of East Africa’s water resources calls for
international cooperation for resource use and
protection (UNEP, 2010; UNEP, 2014).
The impact of climate change on East Africa’s water
resources is not yet fully understood. There are a
number of uncertainties around future precipitation
trends; findings from scientific studies vary
significantly – some forecast an increase in water
availability, while others a decline. Nonetheless, the
majority of studies project that water availability in
the subregion will increase due to climate change
(Bates et al., 2008; Niang et al., 2014). A study by
Döll (2009), for example, predicts that climate
change will have a positive effect on groundwater
recharge in East Africa. According to some
climate change models, most areas in East Africa
can expect an increase in groundwater recharge
Great Ruaha
White Nile
Congo
Tana
Ewaso Ng’iro
Blue Nile
Juba
Shabelle
Omo
Atbara
Water Towers
Major Rivers
Countries
Southern Highlands
Albertine Rift
Kenyan Highlands
Ethiopian Highlands
Tanzania
Sudan, South Sudan, Rwanda,
Tanzania, Uganda, DR Congo
Kenya
Kenya, Somalia (Juba)
Ethiopia, Sudan
Ethiopia, Somalia
Ethiopia, Somalia
Ethiopia, into Sudan
Murchison Falls, Uganda