Physicochemical and Bacteriological Quality of Water from Storage Tanks in a Tertiary Institution in Rivers State, Nigeria

Abstract

Water quality analysis is essential in assessing the suitability of different water sources used for various purposes, including industrial and domestic uses. This study was therefore aimed at determining the physicochemical and bacteriological quality of water samples from different storage facilities in a tertiary institution in Port Harcourt, Rivers State, Nigeria. The study involved eighty (80) water samples obtained from water storage tanks situated at 16 locations within the premises of the institution, to ascertain the physicochemical property, presence and population of different bacterial groups influencing the quality of these water sources. In-situ and ex-situ physicochemical analyses as well as bacteriological investigations were carried out on all samples, using standard laboratory procedures. Results of physicochemical analysis showed that the pH ranged from 4.15±0.14 to 7.16±0.08; conductivity, from 50.55±0.49 (µs/cm) to 364.00±2.83; salinity, from 0.02±0 (ppt) to 0.18±0; temperature, from 27oC to 28oC; Chloride, from 1.03±0.06 (mg/l) to 10.80±0.79; total alkalinity, from 4.00±0 (mg/l) to 11.00±1.41; Dissolved oxygen from 3.04±.020 to 7.36±0.08 (Mg/l) and BOD ranged from 0.81±0 to 4.23±0.09 (Mg/l). Results for bacterial population showed total heterotrophic bacteria ranging from 1.03±1.19 x 103 CFU/ml in water from reservoir tanks at the Faculty of Engineering, to 5.89±2.59 x 103 CFU/ml at Road A Block B; total coliform count ranged from 0 CFU/ml in most samples, to 10.00±2.36 x 102 CFU/ml in Block B reservoir tanks. Water reservoirs in clinic area recorded the highest Salmonella/Shigella counts (1.00±0.23 x 101 CFU/ml) with other stations having zero counts. Hall F (Hostel Ext) on the other hand had the highest counts for Vibrio (2.20±3.01 x 101 CFU/ml). The phenotypic characterization identified Citrobacter spp. as the most occurring (27.27%) bacterial isolate in the study, followed by Alcaligenes faecalis and Klebsiella spp. (18.18% each). Enterobacter spp., Edwardsiella spp., Erwinia psidii, Acinetobacter spp., Pseudomonas spp., Providentia spp. and Salmonella spp. all appeared as the least occurring, having a percentage of 4.55%, each. Tatumella spp. on the other hand had a percentage occurrence of 9.09%. This study has buttressed the need for increased water hygiene of reservoir tanks as well as water sources in these locations.