Morphology of the Kakum River: A study on a small forested River in the Central Region, Ghana

Abstract

The Kakum River, a small-forested but major river in Cape Coast is the main source of water for about five major towns and all communities within its watershed. However, in recent times, it is faced with a lot of challenges including its Brimsu dam producing below designed capacity, relying on water from the Pra river basin, flooding in some parts of the basin and a lot of macrophytes especially in its middle section. This study set out to outline the linkages and influences of headwater and downstream processes and its effects on the Kakum river based on the Holistic approach proposed by Gregory (2006) to understand the consequences of both natural and human activities on such systems. Theories employed include the Geomorphic systems theory and chaos theory. The main data used included Toposheets, DEM, Digital Orthophotos and some field samples (soil, river sediment and water). Analysis employed in the study includes morphometric analysis, morphologic analysis, Laboratory analysis, land-use/land-cover analysis and river bankline analysis. From this study, it was found that Land-use/Land-cover, mainly built-up and rangeland have had profound influence on the river‘s form, water and sediment. It greatly reduced the surface area of the water land-use from 0.52% to 0.32% from 1991 to 2016. The river has responded to these effects through the processes of erosion and accretion. It has therefore been recommended for a major board to be set in order to overlook the various riparian activities that go on within the basin since this basin-wide holistic approach has indicated that past management lacked the integrated approach.