Seasonal and Source-Based Assessment of Physicochemical and Microbial Water Quality in Rocky-Hill Settlements of Southwestern Nigeria

Abstract

Access to safe drinking water remains a critical public health challenge in many rural and semi-urban communities in sub-Saharan Africa, particularly in geologically constrained “rocky-hill” settlements where groundwater availability and quality are highly variable. This study presents a comprehensive experimental assessment of water quality across different water sources and seasonal conditions in selected rocky-hill communities in Southwestern Nigeria.

Water samples were collected from borehole, well, and rainwater sources during both wet and dry seasons. Standard analytical procedures were used to evaluate key physicochemical parameters, including pH, electrical conductivity, total dissolved solids, turbidity, hardness, and major ion concentrations. Microbial quality was also assessed using indicator organisms to determine potential health risks associated with consumption.

Results reveal significant spatial and seasonal variability in water quality across the different sources. Borehole water generally exhibited more stable physicochemical characteristics compared to well and rainwater sources, although seasonal fluctuations were observed, particularly during the wet season. Well water showed elevated levels of contamination indicators, suggesting increased vulnerability to surface infiltration and anthropogenic influence. Rainwater quality varied depending on collection and storage conditions, highlighting potential post-collection contamination risks.

The findings demonstrate that water source type and seasonal variation critically influence water safety in rocky-hill environments. This study provides evidence-based insights for environmental monitoring, rural water management, and public health planning in resource-limited settings. It also underscores the need for improved water treatment strategies and community-level interventions to ensure safe drinking water access.

Keywords: Water quality assessment; seasonal variation; borehole water; well water; rainwater; physicochemical parameters; microbial contamination; rural water resources; rocky-hill settlements; environmental health.

 

Summary:
This study evaluates the physicochemical and microbial quality of water from borehole, well, and rainwater sources in rocky-hill settlements of Southwestern Nigeria across wet and dry seasons. Standard analytical methods were used to assess key water quality parameters. The results show clear seasonal and source-dependent variations, with borehole water generally exhibiting more stable quality, while well water showed higher contamination risks. Rainwater quality varied based on collection and storage conditions. The findings highlight significant environmental and public health implications, emphasizing the need for improved water management and treatment strategies in resource-limited communities.

 

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