“E.Coli was detected at a level of 4CFMU at the Iama school.
The engineering officer monitored free chlorine levels which ranged from 0.26 to 0.38mg/L. The sample at the school was taken from the school tank during the school holidays when the usage was low. It was determined that the chlorine had most likely burned off in the tank due to low usage levels. Hypo 10 was added to the school storage tank. The sampling point was also moved to a location before the water storage tank.
The boil water alert was removed in August 2015.”
“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