Abstract:
With the rapidly growing population in Kenya at an estimated
rate of 3.63% per annum and the resultant high rate of urbanization
coupled with the fact that
75 %
of the country is either arid or semiarid,
the proper management and therefore planning for water resources
development is vital in order to maintain the use of water on a
sustainable basis. The proper management and planning for the use of
water resources calls for the evaluation of the water resources available
within the country and the degree to which they can be exploited. This
paper examines the magnitude of the problems of drought (water
deficit) and floods (water surplus) within two catchment areas in Kenya:
the Nyando and Tana. It is shown that, apart from meteorological
and/or climatological factors, man has greatly influenced the severity
of the two events within the study catchments. The anthropogenic
influences such as large-scale deforestation programmes, damming of
the rivers, urbanization and other development programmes, have to a
large extent affected the return periods of these two events within the
catchments. Various programmes that could be adopted in reducing the
magnitude and/or severity of the two events have been suggested.
Drought has been identified particularly with eastern Kenya which is
comprised mainly of semiarid low-lying land, and the pastoral areas of
northern and southern Kenya. Recently attention has been paid to
climatic variability in the dry areas near Lake Victoria, settlement
schemes in the Rift Valley and the coast province where too much
rainfall and poor soils compound the
problems.
Flooding is particularly
characteristic of western Kenya in the Lake Victoria drainage basin, the
Lower Tana and Athi River reaches and more recently the city of
Nairobi is showing increased vulnerability to floods.