Huonville (Tasmania) – E.coli
E.coli exceedance occurred 8/02/2017 at HVSTE40 Huonville/ Football Club Entrance, Wilmot Rd, Sample Tap. A review of the system found low chlorine residuals within the Ranelagh Reservoir. Reservoir was disinfected and the surrounding pipelines were flushed. A resample was sent for analysis and was clear. Investigation of the cause of the failure was inconclusive.
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
Huonville (Tasmania) – Cobalt
12/7/24: Conara (Tasmania) Cobalt (dissolved total) 0.0001mg/L
There is no guideline for Cobalt and compounds in the Australian Drinking Water Guidelines
Huonville (Tasmania) – Chloroketones
12/7/24: Huonville (Tasmania): 1,1,1-trichloropropanone 3.2ug/L (max), 2.76ug/L (av.)
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
Huonville (Tasmania) – Haloacetonitriles
12/7/24: Huonville (Tasmania) Dichloroacetonitrile 1.8ug/L (max), 1.6ug/L(av.)
“GUIDELINE
Data are inadequate to set guideline values for haloacetonitriles in drinking water
GENERAL DESCRIPTION
Haloacetonitriles are formed from organic precursors during chlorination or chloramination of drinking water. Concentrations of dihaloacetonitriles reported overseas range up to 0.04 mg/L but are typically less than 0.003 mg/L. Concentrations of trichloroacetonitrile are less than 0.001 mg/L.
Trichloroacetonitrile has been used as an insecticide. No data are available on uses for the other haloacetonitriles.
TYPICAL VALUES IN AUSTRALIAN DRINKING WATER
No data are available on concentrations of haloacetonitriles in Australian drinking waters”. ADWG 2011