| Date post: | 14-Apr-2017 |
| Category: |
Engineering |
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SHALLOW WELL WATER QUALITY IN AKURE METROPOLIS, SOUTH
WESTERN NIGERIA.
OJO, Ochuko MaryDepartment of Civil and Environmental Engineering, the Federal
University of Technology, P.M.B 704, Akure, Nigeria.E-mail: [email protected]
Introduction Globally, one person dies from water-related disease every
minute (UNICEF, 2005), while these diseases cause an estimated 12 million deaths worldwide each year (Buor, 2004).
One of the major challenges facing water and Environmental Engineers around the world is the provision of wholesome water to meet the needs of the increasing population.
Approximately one third of the world population use groundwater for drinking and other purposes. Ground water is abstracted through boreholes and wells.
Case study Area and Sampling points This study was carried out in Akure metropolis and a selected
neighboring town. Akure town is located in Akure South Local Government Area of Ondo
State, South Western Nigeria.
Sources of potable water in the study Area
METHODOLOGY The well water samples were randomly selected and
subjected to comprehensive physical, chemical and bacteriological analysis.
The physicochemical examination of the water samples were completed within six hours of sample collection.
The pH of each water sample was determined using a calibrated pH meter. The colour and turbidity of each sample was measured with a digital spectrophotometer.
A calibrated conductivity meter was employed for the determination of the Conductivity of the water samples.
Other chemical analyses of the samples were done using methods specified in APHA (2005).
Results and Discussion A comparison was made with the WHO drinking
water standards.
Some variations were observed in the chemical and bacteriological characteristics of the water samples.
Results and Discussion continuedThe Total Dissolved Solids (TDS) content ranged from 189.4 to 865.7. 30% of the water samples had TDS values higher than the WHO recommended limit of 500mg/L. TDS is an indication of organic salts and dissolved materials in water.
The conductivity values ranged from 172to 910mg/L, but none of them exceeded the WHO maximum limit of 1000mg/L. Conductivity could be an indicator of mineralization or salinity problems and could affect physical properties such as colour, taste and odour.
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Results and Discussion continued
The water samples met the WHO requirement for total bacterial count for drinking water as none of them exceeded the maximum limit of 100 CFU/100mL. However, 60% of the well water samples had E.coli present. The presence of e-coli in water is an indication of the presence of faecal contamination.
The pH values of 90% of the well water samples did not fall within WHO recommended standard of 6.5 to 8.5. Low water pH can cause gastro-intestinal irritation in sensitive individuals.LAFE2ILA
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Conclusion and Recommendation The physical analysis carried out revealed that most the
well water samples met up with the W.H.O standards in terms of odour, total suspended solid, taste, temperature and turbidity
The concentrations of heavy metals, conductivity, TDS and total hardness were also within permissible limits set by WHO.
However, elevated level of pH above WHO permissible limits in some samples pose serious health concern
Some of the well water samples contain coliform which is an indication of contamination by faecal organisms.
Suitable treatment, preferably disinfection is recommended
