Physiochemical Parameters and Groundwater Resource in the Eastern Dahomey Basin, Southwestern Nigeria

Abstract

 Groundwater which accounts for 30% of the estimated earth's freshwater is an essential natural resource stored in the subsurface geological formations in the critical region of the earth’s crust for sustaining ecosystems and human well-being. One of the challenges in water resources management in semi-arid and tropical regions like Eastern Dahomey basin, Lagos state, Nigeria is how to sustainably manage groundwater resources in relation to water pollution. Despite its importance, groundwater management in the region has been hampered by lack of comprehensive policies, leading to overexploitation and contamination issues. Therefore, a better understanding of the quality processes to a changing future is necessary. This study delves into assessing the groundwater quality in Eastern Dahomey basin, aiming to provide insights for effective management in the face of growing water pollution, scarcity and in relation to the world Health Organisation (2022) and Standard of Nigeria (2015) standard for drinkable water. Fourteen parameters were investigated on forty samples selected from a transient mapping of 6km square transient and the dug wells samples were selected randomly. The samples were taken to the laboratory for in depth analysis for both dry and wet season to denote seasonal variation and climate change impacts. Findings showed significant variations in physiochemical groundwater quality across seasons and parameters. pH levels fluctuated, likely due to rainfall and evaporation, but remained within standard ranges. Odors varied, with most samples not meeting odorless standards. Appearance showed particle concentrations mixed, with clarity below standard. Temperature also varied between seasons but conformed to standard guidelines. The study recommends the development of integrated water resource management plans, adoption of sustainable land use practices, and robust monitoring systems to ensure the long-term viability of groundwater resources. Moreover, there is a pressing need for stringent regulations, comprehensive awareness campaigns, and collaborative research efforts to address groundwater quality issues and promote sustainable groundwater use. By implementing these recommendations, stakeholders can mitigate the adverse impacts of climate change, safeguard groundwater resources, and ensure the well-being of present and future generations in the Eastern Dahomey Basin and similar regions globally.

Keywords: Physiochemical, Groundwater, Resource, Dahomey, Basin