2012 August – Korumburra – Bena Road (Victoria) – E.coli

Bena Road – Korumburra (Victoria) – E.coli
A low-level E.coli detection was recorded for a non-regulatory sampling site at the Bena Road standpipe in Korumburra on the 8th August 2012. There were no microbiological detections for three other sites sampled in Korumburra on that day. Mains flushing was carried out prior to a resample being collected from the standpipe on the 10th August. Samples were also collected from four other customer tap sites on the western side of the town. Analysis found no detectable E. coli or other coliforms in any of the follow-up samples,verifying that the water supply system was clean and the original detection was an isolated incident.

Escherichia coli should not be detected in any 100 mL sample of drinking water. If detected
in drinking water, immediate action should be taken including investigation of potential
sources of faecal contamination.

“Coliforms are Gram-negative, non-spore-forming, rod-shaped bacteria that are capable of aerobic and facultative anaerobic growth in the presence of bile salts or other surface active agents with similar growth-inhibiting properties. They are found in large numbers in the faeces of humans and other warm-blooded animals, but many species also occur in the environment.

Thermotolerant coliforms are a sub-group of coliforms that are able to grow at 44.5 ± 0.2°C. E. coli is the most common thermotolerant coliform present in faeces and is regarded as the most specific indicator of recent faecal contamination because generally it is not capable of growth in the environment. In contrast, some other thermotolerant coliforms (including strains of Klebsiella, Citrobacter and Enterobacter) are able to grow in the environment and their presence is not necessarily related to faecal contamination. While tests for thermotolerant coliforms can be simpler than for E. coli, E. coli is considered a superior indicator for detecting faecal contamination…” ADWG 2011