Sorell (Tasmania) – E.coli
17/3/20: Sorell (Tasmania) 2 MPN100/mL
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
Sorell – Tasmania – Turbidity
August 11 2015: Sorell (Tasmania) William St – Turbidity 22 NTU
June 7 2016: Sorell (Tasmania) William St – Turbidity 31 NTU
4/8/20: Sorell (Tasmania). Turbidity 22 NTU
Chlorine-resistant pathogen reduction: Where filtration alone is used as the water treatment
process to address identified risks from Cryptosporidium and Giardia, it is essential
that filtration is optimised and consequently the target for the turbidity of water leaving
individual filters should be less than 0.2 NTU, and should not exceed 0.5 NTU at any time
Disinfection: A turbidity of less than 1 NTU is desirable at the time of disinfection with
chlorine unless a higher value can be validated in a specific context.
Aesthetic: Based on aesthetic considerations, the turbidity should not exceed 5 NTU at the
consumer’s tap.
Sorell (Tasmania) – Chloroketones
29/7/24: Sorell (Tasmania): 1,1,1-trichloropropanone 2.1ug/L
Data are inadequate to set guideline values for chloroketones in drinking water. GENERAL DESCRIPTION The chloroketones are produced in drinking water as by-products of the reaction between naturally occurring organic matter and chlorine. No data are available on other sources or uses for these compounds. Concentrations of chloroketones in drinking water reported overseas are very low and are estimated at less than 0.01 mg/L.
TYPICAL VALUES IN AUSTRALIAN DRINKING WATER In major Australian reticulated supplies 1,1,1-trichloropropanone has been recorded in concentrations up to 0.02 mg/L, but it is usually below the limit of determination of 0.0005 mg/L. No data are available for other chloroketones.
LIMITING FORMATION IN DRINKING WATER The presence of chloroketones in drinking water can be minimised by removing naturally occurring organic matter from the source water, by reducing the amount of chlorine added, or by the use of alternative disinfectants.” 2011 ADWG
Sorell (Tasmania) Chloropicrin
29/7/24: Sorell (Tasmania) Chloropicrin 1ug/L (max)
No Guideline level for Chloropicrin
Chloropicrin is formed in water by the reaction of chlorine with humic acids, amino acids, and nitrophenols. The presence of nitrates increases the amount formed (6). Chloropicrin has been detected in drinking-water; however, in the presence of reducing agents, it is converted
into chloroform