A comparative study of the pollution status of Sakumo II and Muni Lagoons in Ghana

The pollution status of Sakumo II and Muni Lagoons and Mamahuma and Gbagbla Ankonu
feeder streams, which feed Sakumo II along the coast of Ghana, were assessed and compared.
As expected of saline waters, pH values of both lagoons fell within a slightly neutral to saline
range whilst, the feeder streams were moderately saline. Conductivity distribution also showed
saline (.5.0mScm21) characteristics of the lagoons, while, the feeder streams are brackish
(1.5–5.0mScm21). DO concentrations in both lagoons indicated a wide variation. Relatively high
BOD and nutrients content of Sakumo II and the feeder streams suggested that, Sakumo II and its
feeder streams are moderately to grossly polluted. However, Muni Lagoon was characterized
by relatively low BOD and nutrients content suggesting relatively low anthropogenic impact.
The ionic dominance patterns for Sakumo II and Muni Lagoons were: Na+ . Mg2+ . Ca2+ and
Cl2 . HCO32 . SO422, Na+ . Ca2+ . Mg2+ and Cl2 . HCO3 2 . SO4 2 2, respectively. Using water
quality index (WQI), Sakumo II was found to be grossly polluted and requires mitigation measures,
while, Muni Lagoon was of fairly good quality and requires monitoring.
Key words | coastal lagoons, Ghana, pollution status, water quality