Using Geospatial Information Component to Monitor the Watersheds along the Densu Basin in Ghana

Abstract

The Densu basin is a coastal river catchment in southern Ghana and a typical rural community like all other rural settlements in Ghana. It is the only basin amongst 43 other basins of the country that supplies water to two regional capitals of Ghana, namely, the capital city of Ghana, Accra and Eastern regional capital, Koforidua. The qualities of these water resources vary naturally and widely depending on climate, season, and the geology of the bedrock, as well as anthropogenic activities. The primary aim of this research is to determine data requirements for efficient and costeffective development of a Geographic Information System (GIS) to map and detect the extent of the sources of the watersheds and how to protect the environment for continuous supply of water. Among the Nine catchment areas, only one catchment WSA_05 (Koforidua Township) was determined to have a very high risk of being vulnerable and therefore required urgency to protect environment for continuous supply of water. Four catchment areas WSA_02 (Weija Dam), WSA_03 (Apedwa-Asafo), WSA_06 (Suhum) and WSA_09 (New Tafo) were determined to have a high risk of being affected and therefore there was the need to protect the environment for continuous supply of water. Ghana as a country will have to take a responsible step in protecting its water body and its environment to enable continuous and sustainable supply of water to its citizens. This study therefore reveals the state of the water users and how urgent it environment needs to be protected.

Assessment of the quality of the Densu river using multicriterial analysis and water quality index

“…1) is noted for its immense socioeconomic importance to Ghana. The Densu river provides water for the Western sectors of Accra through the Weija Treatment plant (Nee-Whang 1999; Obeng 2005;Asamoah et al 2008;Owusu 2012;Antwi-Agyakwa 2014;Nyamekye et al 2016).…”

“…The major rainy period in the basin ranges from late February to late July with the peak in June, while the minor rainfall season occurs between August and late October (Water Resources Commission 2014; Nyamekye et al 2016). The mean annual rainfall ranges between 450 and 1900 mm (Dickson Adomako et al 2011a, b).…”