Assessing the Performance of Dompoase Wastewater Treatment Plant and Its Effect on Water Quality of the Oda River in Kumasi
Treatment performance of the Dompoase wastewater treatment plant and the effect of final effluent on the Oda River were evaluated. Influent and effluent wastewaters as well as receiving water qualities were monitored for a period of three months within 2 weeks intervals. The study showed mean percentage removal of 51.23 (± 15.34), 89.18 (± 8.43), 36.11 (± 34.65), 80.80 (± 17.85), 58.02 (± 41.05), 22.51 (± 15.53), 22.23 (± 18.93), 60.94 (± 42.79), 68.52 (± 26) and 92.20 (± 3.82) % for TDS, TSS, Fe, COD, BOD, N, P, Pb, total coliforms and faecal coliforms respectively. In contrast, K and pH revealed higher mean effluent than influent values, hence percentage removals of -27.59 (± 34.40) and - 10.24 (± 1.03) were obtained for K and pH. Reduction from influent to effluent values showed statistical significant differences among mean values for TDS, TSS, COD, BOD, N, K, pH, and Pb (P<0.05). However, there was no significant difference observed for mean values of P, Fe, total and faecal coliforms (P>0.05). Total dissolved solids (TDS), TSS, COD, BOD, N, P, Pb, total coliforms and faecal coliforms in effluent wastewater were above the recommended EPA guidelines. But pH was in the acceptable range of 6- 9. It was concluded that effluents fell short of standard requirement before discharge into surface waters. Even though, concentrations of all parameters decreased with distance from the discharge point in River Oda, downstream values of most parameters were higher than upstream values. Water quality parameters of the Oda River were affected as rainfall increases from May through to July.
A Thesis submitted to the Department of Theoretical and Applied Biology Kwame Nkrumah University of Science and Technology in partial fulfillment of the requirements for the degree of Master of Science in Environmental Science, November-2010