ASSESSMENT OF THE MICROBIOLOGICAL AND PHYSIOCHEMICAL QUALITIES OF WATER SOURCED FROM DIFFERENT TREATMENT TANKS AT A MUNICIPAL DAM LOCATED IN BENIN CITY, EDO STATE, NIGERIA

Abstract

The culturable microbial profile of water and biofilms associated with the internal walled surface of different treatment tanks at the Benin City water dam facility were investigated using techniques such as serial dilution and pour plate methods. The physiochemical attributes of the stored water were determined using methods which included the use of appropriate meters and titrimetery.The pathogenicity of the biofilm bacterial isolates was determined using the rabbit ileal loop assay. The mean heterotrophic bacterial, fungal and coliform counts ranged from 0.2 × 102cfu/ml to 9.3 × 105cfu/ml, 3.7 ×105 cfu/ml to 6.7 ×105cfu/ml and 18 MPN/100 ml to 180 MPN/100 ml respectively. Several microbial isolates which included Bacillus sp.,Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis, Klebsiella pneumoniae, Staphylococcus epidermidis, Klebsiella mobilis, Micrococcus sp., Flavobacterium sp, Aeromonas sp, Klebsiella sp., Rhizopus stolonifer, Aspergillus flavus, Aspergillus niger, Penicilliumsp., Fusariumoxysporum, Neurospora sp., Mucorsp. and Rhizopus stolonifer were present in both the water and swabbed tank walls. There was fluid accumulation in ileal loops inoculated with Escherichia coli and Staphylococcus epidermidis whilst fluid accumulation was absent in ileal loops seeded with P. aeruginosa, P. mirabilis, K. pneumoniae and B. subtilis respectively.The pH and turbidity readings ranged from 6.6 to 7.2 and 2 NTU to 10 NTU. The authorities managing the water dam facility should improve on their current treatment and disinfection methods