Abstract:
This ongoing study assesses the presence of Escherichia coli (E. coli) and Total Coliform
bacteria in sea beach waters at two popular tourist destinations, Arugam Bay and Pasikuda,
located in eastern Sri Lanka, from January to June, 2025. Seven water samples from different
location of each places which 100 m far from shore were analysed at a time using the
Membrane Filtration method to enumerate microbial levels and two samplings were done
per month. The spatial and temporal variations between the two sites were compared.
Results revealed a considerable month-to-month variation in contamination levels, in spite
of the general similar trend of overall changes in both sites. It might be due to the changing
environmental factors or worse anthropogenic activities. The water samples from Pasikuda
recorded the higher E. coli and Total Coliform colony counts than the water sample from
Arugam Bay, While the counts resulted for Arugam Bay waters peaked in April, 2025 (24.9
CFU/100 ml), the highest E. coli level (61.6 CFU/100 ml) was observed in beach waters
from Pasikuda in March, 2025. Total Coliform levels were highest in Pasikuda beach water
in January (135.6 CFU/100 ml) and in Arugam Bay waters in March (116.3 CFU/100 ml).
The lowest contamination levels for both sites were recorded in May, 2025. Statistical
analysis indicated significant differences in Total Coliform levels between sites in January
(p = 0.001) and in E. coli levels in March (p = 0.021). These findings highlight the
importance of continuous monitoring and site-specific management strategies to ensure safe
recreational waters in Sri Lanka’s coastal zones which is more influencing the tourism
industry.
