2011 December + 2014 April – Maribyrnong (Victoria) – E.coli

Maribyrnong – Victoria – E.coli
one detection (nine organisms per 100mL) in a non-routine sample from Maribyrnong locality on 2 December 2011. The detection is considered to have been caused by use of a portable standpipe to obtain the water sample under non-aseptic conditions. No other samples, whether upstream or downstream, including repeat sampling, showed presence of E. coli.
one detection (eight organisms per 100mL) in a non-routine sample in Maribyrnong locality on 16 April 2014. The detection is considered to have been caused by the sample having been taken from a temporary house connection under non-aseptic conditions during commissioning of newly constructed water mains. Repeat sampling the next day from a nearby front garden tap confirmed the absence of E. coli in the water supply.


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