Assessment of Physical Water Quality Parameters of Borehole Water in Enugu State: A Comparative Analysis of Wet and Dry Seasons

Abstract

This study assessed the physical water quality parameters of borehole water in Enugu State and examined the influence of seasonal variation on these parameters. Enugu State is characterized by two seasons: the wet season, which covers April to October, and the dry season, covering November to March. For this study, twelve borehole locations in Enugu North Local Government Area were selected, and water samples were collected monthly over a six-month period spanning from Jun to August 2023 (wet season) and from November 2023 to January 2024 (dry season). Standard analytical procedures prescribed by the American Public Health Association (APHA, 2017) were employed to measure pH, temperature, turbidity, electrical conductivity (EC), total dissolved solids (TDS), and total suspended solids (TSS). Descriptive statistics and paired sample t-tests were used to compare seasonal variations, while results were evaluated against the World Health Organization (WHO, 2017) drinking water quality standards. Findings revealed varying degrees of seasonal influence across the parameters. pH values showed minimal variation and generally conformed to WHO guidelines, except in a few samples that recorded slightly elevated values. Temperature was significantly higher during the dry season, although all values were within WHO limits. Turbidity was consistently higher in the wet season but remained far below the 1 NTU standard. EC and TDS exhibited marked increases in the dry season, reflecting reduced dilution and increased ion concentration. Conversely, TSS displayed no significant seasonal differences. The t-test results confirmed significant seasonal variation in temperature, turbidity, EC, and TDS, while pH and TSS showed no statistically significant differences. The findings indicate that although the borehole water in Enugu North generally meets WHO physical water quality standards, seasonal fluctuations, particularly during the dry season, pose potential risks to long-term groundwater quality and public health monitoring.