Abstract:
The study was aimed to determine the water quality of the collector wells in the Vallipuram
area of the northern Sri Lanka and to determine the suitability of the water for domestic
utilization. Because of the infection of well water by iron and coliform bacterial species in
2016, public water supply was temporarily stopped and after a complete sterilization and
clean-up process using chlorination and integrated control methods only, the water supply
restarted after six months. Since then, there had been no steps made to check the quality of
the drinking water supplied to the public from these wells. Water samples (36) were collected
from the four major water supply collector wells in both top, middle and bottom randomly in
triplicates during the rainy season of 2018. Samples were analyzed for pH, Electrical
conductivity (EC), Turbidity, Total iron, Colour, Coliform test and Bio chemical tests such as
Indole production test, Methyl red test,Voges-Proskauer test, Oxidase test and Catalase test.
The results were compared with WHO and SLS standards and it was concluded that all the
water samples from the collector wells tested, did not have any contaminants thus the quality
of those samples was good for drinking.Based on the biochemical and molecular analysis,the
bacterial species presented in some water samples was identified as Bacillus
thuringiensis. Exactly similar conclusion was reached when the same research study was
repeated after 6 months from the earlier study and the values obtained for the physico
chemical factors tested were not significantly different with that of the previous study.
Therefore, water in all the collector wells could be used for domestic and sustainable
agricultural purposes continuously in the future too.
