30/11/17: Cobradah Court, Pimpana
On 30 November 2017, a positive detection of E. coli (2 MPN/100mL) occurred with non-routine monitoring of the supply reservoir in the Pimpama Coomera WSD. The free chlorine residual at the site was 0.19 mg/L.
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