PhD Thesis Emmanuel Obeng Bekoe - Cranfield University

Emmanuel Obeng Bekoe Phd Thesis Chapter 1 Background and Problem
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instruments. However for the IWRM projects to be sustainable GWP/TAC
(2000) advocated for the implementation of these principles that the ”user pays,
polluter pays; and subsidize the good and tax the bad”.
Yet advocating of IWRM principles (Lee, 1995; GWP/TAC, 2000) there are still
piecemeal approaches to water resources management problems known to
culminate in environmental degradation such as 1) over exploitation of the
surface water resources due to lack of good planning and effective water saving
measures resulting in decrease in ground water recharge by nearly 74% from
the 1960’s to 1990’s as a result of population increase in China (Ma et al.,
2005); 2) Ngana et al., (2004) concluded that unsustainable utilization and
management of natural resources (land, pasture and water resources) were the
core problems in Tanzania that led to environmental degradation such as
shortage of land and decreased river flows in the Lake Manyara sub-basin; 3)
Singh (2000) showed that in the Haryana province of India, environmental
degradation occurred as a result of over exploitation of groundwater which
caused an attendant increase of the shallow water table height of over 1m/a
since 1985, culminating in water logging and attendant floods. This he noted
occurred even though the green revolution which brought about self sufficiency
in food production is a success in that basin.
For the solution to some of these water resources management problems, one
approach to assisting sustainable development within river basins, and to
contribute to the water resources assessment ‘toolkit’, is the development and
use of mathematical modelling of watershed hydrology (Singh and Woolhiser,
2002 and Borah and Bera, 2003). Considerable work has been undertaken in
understanding and modelling the processes involved in the hydrological cycle,
enabling models to have been developed to address a wide spectrum of
environmental and water resources problems (Singh and Woolhiser, 2002 and
Borah and Bera, 2003)). Examples of models used to solve hydrological
problems (Singh & Woolhiser, 2002) include the HEC-HMS 1 model, which is
1 Hydrologic Engineering Centre-Hydrologic Modelling System (HEC, 2000)