Westbury (Tasmania) – E.coli

28/12/17: Westbury (Tasmania) E. coli of 4.1 MPN/100mL in weekly compliance sample

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

Westbury – Tasmania – Temperature

January 19 2016: Westbury (Tasmania) – Temperature 21C

February 9 2016: Westbury (Tasmania) – Temperature 22C

February 23 2016: Westbury (Tasmania) – Temperature 20.5C

GUIDELINE

“No guideline is set due to the impracticality of controlling water temperature.
Drinking water temperatures above 20°C may result in an increase in the number of
complaints.

Temperature is primarily an aesthetic criterion for drinking water. Generally, cool water is more palatable than warm or cold water. In general, consumers will react to a change in water temperature. Complaints are most frequent when the temperature suddenly increases.

The turbidity and colour of filtered water may be indirectly affected by temperature, as low water temperatures tend to decrease the efficiency of water treatment processes by, for instance, affecting floc formation rates and sedimentation efficiency.

Chemical reaction rates increase with temperature, and this can lead to greater corrosion of pipes and fittings in closed systems. Scale formation in hard waters will also be greater at higher temperatures…

Water temperatures in major Australian reticulated supplies range from 10°C to 30°C. In some long, above-ground pipelines, water temperatures up to 45°C may be experienced…

The effectiveness of chlorine as a disinfectant is influenced by the temperature of the water being dosed. Generally higher temperatures result in more effective disinfection at a particular chlorine dose, but this may be counterbalanced by a more rapid loss of chlorine to the atmosphere (AWWA 1990).

Westbury (Tasmania) Turbidity

14/7/20: Westbury (Tasmania) – Turbidity 5.59NTU (max)

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.

Westbury  (Tasmania) – Chloroketones 

27/8/24: Westbury (Tasmania): 1,1,1-trichloropropanone 2.9ug/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

Westbury (Tasmania) – Haloacetonitriles 

27/8/24: Westbury (Tasmania) Dichloroacetonitrile 2.3ug/L

“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

2016/24 – Westbury (Tasmania) – E.coli, Temperature, Turbidity, Chloroketones, Haloacenitriles

Westbury (Tasmania) – E.coli 28/12/17: Westbury (Tasmania) E. coli of 4.1 MPN/100mL in weekly compliance sample 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 Westbury – Tasmania – Temperature January 19 2016: Westbury (Tasmania) – Temperature 21C February 9 2016: Westbury (Tasmania) – Temperature 22C February 23 2016: Westbury (Tasmania) – Temperature 20.5C GUIDELINE “No guideline is set due to the impracticality of controlling water temperature. Drinking water temperatures above 20°C may result in an increase in the number of complaints. Temperature is primarily an aesthetic criterion for drinking water. Generally, cool water is more palatable than warm or cold water. In general, consumers will react to a change in water temperature. Complaints are most frequent when the temperature suddenly increases. The turbidity and colour of filtered water may be indirectly affected by temperature, as low water temperatures tend to decrease the efficiency of water treatment processes by, for instance, affecting floc formation rates and sedimentation efficiency. Chemical reaction rates increase with temperature, and this can lead to greater corrosion of pipes and fittings in closed systems. Scale formation in hard waters will also be greater at higher temperatures… Water temperatures in major Australian reticulated supplies range from 10°C to 30°C. In some long, above-ground pipelines, water temperatures up to 45°C may be experienced… The effectiveness of chlorine as a disinfectant is influenced by the temperature of the water being dosed. Generally higher temperatures result in more effective disinfection at a particular chlorine dose, but this may be counterbalanced by a more rapid loss of chlorine to the atmosphere (AWWA 1990). Westbury (Tasmania) Turbidity 14/7/20: Westbury (Tasmania) – Turbidity 5.59NTU (max) 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. Westbury  (Tasmania) – Chloroketones  27/8/24: Westbury (Tasmania): 1,1,1-trichloropropanone 2.9ug/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 Westbury (Tasmania) – Haloacetonitriles  27/8/24: Westbury (Tasmania) Dichloroacetonitrile 2.3ug/L “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