A Number Description of Ghanaian Water Quality—A Case Study of the Southwestern and Coastal Rivers Systems of Ghana

Abstract

The CSIR Water Research Institute\rundertook water quality monitoring and assessment of the Southwestern and the\rCoastal Rivers Systems of Ghana from 2005 to 2008 for the Water Resources\rCommission of Ghana (WRC) under WRIS II Project, a Danish Government Funded\rProject. The Southwestern and the Coastal Rivers Systems cover approximately 30%\rof the total drainage basins of Ghana. A total of 19 surface water stations\rwere selected for the monitoring programme. The Adapted Water Quality Index\r(WQI) was to be used as a tool to classify the overall ambient water quality at\rthe 19 different stations. The index classified water quality into one of four\rcategories: good (Class I, >80), fairly good (Class II, 50 - 80), poor\r(Class III, 25 - 50), and grossly polluted (Class IV, 4-N), Faecal Coliform (FC), pH, Nitrate as Nitrogen (NO3-N),\rPhosphate as Phosphorus (PO4-P), Total Suspended Solids (TSS), Conductivity\rand Temperature. Evaluation of the waters with the WQI indicated that most\rGhanaian waters are currently in Class II, the fairly good water quality state,\rbut with variations in this range within the seasons and stations, and from one\rwater body to the other. Potroase in the Densu basin had the best water quality\rduring the study period while Nsawam had the poorest. Efforts should be made to\rprevent further pollution of the waters to improve their quality.