2016 – Ball Bay/Halliday Bay – (Queensland) – E.coli

2016 March: 8 MPN/100mL.

There were less than 100% of samples which complied with the nil E.coli standard for the
Mackay and Sarina water supply schemes (see grey shading in Table 3-1) due to an E.coli
detection at Ball Bay/Haliday Bay Reservoir in March 2016 and at Sarina Apex Park in March
2017.

“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