Quantifying the role and benefits of wetlands for environmental security, ecosystem sustenance, and economic development is complex. Natural wetlands could serve as treatment plants in most developing countries if managed correctly and sustainably. This study was conducted on a natural coastal wetland in Ghana’s central region. In assessing the ability of the wetland to remediate waste and wastewater channeled into it, water samples were collected from inflow points and within the wetland under study. The laboratory analysis was conducted in the dry and wet seasons, and the results show that the wetland had little to negligible effect in treating the wastewater. The Nemerow’s Pollution Index shows that the majority of the parameters studied contributed to pollution. Dissolved Oxygen and Ammonia are the most prominent metrics that accounted for pollution. Water Quality Index displayed values ranging from 1007 to 4857, including Dissolved Oxygen and Ammonia in the index calculation, whereas a range of 17 to 61 was obtained without them. Over the past 30 years, the wetland under investigation has seen huge encroachment and waste discharge from diverse sources such as grey water, black water, industrial effluents, and commercial untreated waste. The wetland land cover indicates a considerable loss in size from 1991–2020 by 83.24%. This study shows that the wetland could not treat wastewater because it has been converted into a dump site instead of its known use as a remediation site.

Graphical Abstract