2015 February – Theodore (Queensland) – E.coli

Theodore (Queensland): E.coli
E.coli Detection – Theodore: E.coli were detected in two samples collected from the Theodore water reticulation network on 26/02/2015. Incident DWI-7-504-00040 refers. The counts recorded were 1 E.coli per 100ml at both locations, with chlorine disinfection residuals of 0.59 mg/L and 0.22 mg/L respectively. Chlorine levels in the system were checked and suitable levels of free chlorine identified. Both in house follow-up sampling (using coli-tabs) and external laboratory analysis by Qld Heath indicated that follow up samples were free of E.coli.
Banana Shire Drinking Water Quality Management Plan 2014-15

“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