CONTENTS-
Abstract
Introduction
Material and Methods
Results and Discussion
Conclusion
Bibliography

Bacterial pollution of groundwater has become a major problem in India. It is mainly due to lack of safe drinking water and proper sanitation and indiscriminate sinking of tube wells, which has resulted in causing various water borne diseases. The present study was aimed with the main objective of assessing the MPN/100 ml and E.coli level of groundwater (openwells, borewells) in various parts of Mysore city. The work represents results of E.coli test of 100 selected water samples, during the summer seasons (2002). The values of MPN/100ml are found to vary from 3 to 2400 /100ml. The high values of MPN are observed in northern (Mandimohalla, N.R. Mohalla, Metagalli) and eastern (Vidyaranyapuram, Laxmipuram) part of city. The unplanned release of large amount of sewage water into the subsurface is responsible for bacteriological pollution of groundwater in the area.

Water is precious for life. The fast growth of population has led to the rapid scarcity of safe drinking water. Corporations have switched from rivers and lakes to groundwater. Pollution in open waters is understandable; but in present day even ground water is contaminated. Ground water is a major source of water to most of the regions in Mysore city though a river flows just 20 km from the city.

Groundwater pollution has been defined as - impairment of water quality by heat, chemicals or bacteria to a degree, that does not create an actual public health hazard but adversely affects the water for domestic, farm, municipal and industrial use. Shallow wells are notoriously liable to pollution from neighbouring sources of contamination (Garod et.al., 1997) like latrines, urinals, drains, composts, soakage pits and collection of manure. Presently bore-wells are also getting increasingly polluted which lodge pathogenic microorganisms like E.coli and related organisms, coliforms. The coliform group includes E. coli, Enterobacter aerogens and Klebsiella pneumoniae . These are formulative, anaerobic, gram negative, non-sporing, rod shaped bacteria that ferment lactose with gas formation within 48 hours at 35 ° C. The bacteriological quality of water is generally expressed in terms of E.coli and total bacteria. These are important water quality parameters from public health point of view. They play a key role in water-borne diseases. The present study was undertaken to record fecal indicator bacteria and total bacteria in hundred water samples collected from wells and borewells of Mysore city.

Hundred water samples were collected from all existing open and bore wells of Mysore city, used for domestic and drinking purposes. These samples were analysed for biological parameters like MPN of coliform as per the methods of Trivedy and Goel (1985) and H 2 S strip test by Manja et.al (1982); Manja and Kaul (1992), Manja (1994) were estimated using standard methods during summer of 2002.

Biological characteristics of drinking water of Mysore city are presented in Table 1. The MPN of coliform bacteria varied from 3 to ³ 2400/100ml.

The rating of drinking water quality based on various standards is presented in Table 1. The results of the bacterial analysis in each zone are presented in Table 2 and Table 2.1. 25 samples were analysed in each zone. In north zone, one sample each belongs to satisfactory and suspicious categories respectively, while 23 samples were of unsatisfactory class. The only two samples that were not too much polluted were from Banimantap

where the usage of groundwater accounts for only 30%.

In the south zone, 6 samples belonged to the satisfactory class, 2 were suspicious while 17 samples were rated as unsatisfactory. J.P. Nagar area had all the wells categorised as unsatisfactory where the usage of water was 90%. Water samples of the east zone seemed to be quite similar to north zone. Interestingly wells that was lesser used were also polluted to a greater extent as these samples were collected from open wells.

A much interesting result is that the bore well waters of west zone had the greatest usage ranging from 50-90% and yet there were only two samples that fall under unsatisfactory class, 13 samples were satisfactory and only 10 samples fall under suspicious class. Overall, considering a majority of groundwater samples (64%) belong to the unsatisfactory class; 15 samples to the suspicious class, 21 samples to the satisfactory class, while none of the samples would be classified as excellent. The probable reason   for this is the improper use of water, where the activities around these wells is very intense, leading to seepage by used water. Moreover, samples collected represent only the summer months during drought conditions. Analysis for the other two seasons would give a better understanding of the quality of borewell water.

As the need for groundwater is increasing day by day due to the shortage of major river sources, there is an urgent need to educate the communities regarding the proper usage of valuable groundwater

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Manja K.S. (1994) Simple microbiological methods for water quality testing and their field applications. Micon 84 and 35 th AMI conference (9 th –12 th Nov. 1994)

Manja K.D. and Kaul R.K. (1992); Efficacy of a simple test for bacteriological quality of water. J. Ind. Assoc. Env. Managemnet 19:18-20

MHC (1957) British Ministry of Health Classification

MWBLC (1975). Meteropolitan Water Board London Classification.

Preeti Mukerjee and Kaik M.L. (1997). Bacteriological water quality of the ponds of Raipur city. Proc. Acad Environ Biol. 6 (1), 77-79.

Richariya L.K. and Mishra Ravi (1998) MPN and E.coli in samples of Rewa area (M.P.) India. Journal of Environment and Pollution 5(1)., 73-77.

Trivedi R.K. and Goel P.K. (1984) Chemical and Biological Methods for water Pollution studies. Environ Publ. Karad India.

DOS in Botany
* DOS in Environmental Science
University of Mysore, Manasagangotri,
Mysore – 570 006. Karnataka. India.