World Journal of Biology and Biological Sciences

World Journal of Biology and Biological Sciences Vol. 3 (1), pp. 001-004, December 2015, ISSN 2331-1894 ©2015 World Science Research Journals

Full Length Research

Comparative study of bacteriological quality of open and closed well water in Ozoro Metropolis, Delta State

Okere O. L.  and Orogu J. O.*

Department of Science Laboratory Technology, School of Science and Technology, Delta State Polytechnic Ozoro, Delta State, Nigeria. 

*Corresponding author. Email:

Accepted October 08 2015 


The bacteriological analysis of open and closed well water in Ozoro, Delta State, Nigeria was assessed with a view to ascertain the bacteriological quality of well water. Six samples were collected from different wells and were labeled as A, B, C, D, E, F; Samples A and B were collected from wells for private use only and was always closed. Samples C and D were collected from wells for public use and were always opened. Samples E and F were collected from wells for private use and always closed, though occasionally opened for public use. A total of 6 bacterial species were isolated from the various samples analysed, they were; Escherichia coli, Streptococcus faecalis, Proteus mirabilis, Staphylococcus aureus, Clostridium perfringens and Klebsiella pneumonia. Heterotrophic plate count (HPC), total enteric bacterial count and total coliform count using the most probable number (MPN) as well as some physiochemical parameters such as pH and temperature were determined. HPC ranged from 1.7×106 to 7.1×106cfu/ml, total enteric bacterial count ranged from 1.1× 106 to 4.2×106 cfu/ml and total coliform count ranged from 0 to 1.8×103cfu/100 ml.  Open well water recorded the higher HPC, enteric bacteria count and MPN than closed well water. The pH values ranged from 7.1 – 7.5, temperature ranged from 24.0 to 26.0°C. C. perfringes were the most isolated among all the bacteria with 100% occurrence, while S. faecalis had the least occurrence with 50%. The presence of higher number of pathogenic K. pneumonia, E. coli and C. perfringens among others, encountered in well water is alarming. The presence of these organisms in water should receive particular attention, as their presence indicate public health hazard. 

Key words: Open well, closed well, Bacteriological, enteric bacterial, total coliforms.