Australian Drinking Water Map

2009 July – 2011 November – Longreach (Queensland) – E.coli
 
Number of samples 213. Max 9, Average 0.14
 
2014/15: No E.coli detected since January 2010. 7 samples above ADWG

Incident Description: Detection of E. coli in the reticulation system. Possible contamination of sample. In-house testing from the same sample point on the same day was clear and had free chlorine of 1.41. Water treatment plant operator also took sewerage samples on the same day and likely contaminated a sample bottle prior to reticulation sample being taken. Corrective and

Preventative Actions: Three additional samples were taken one from the same sampling point, one from before and one from after on the same line. All samples came back clear of E. coli. The line was flushed and staff were retrained on sampling.

Longreach Regional Council Drinking Water Quality Management DWQMP – Annual Report
30 June 2014 – 30 June 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 2011

2009/11 – Longreach (Queensland) – Fluoride
 
2009/11: Longreach (Queensland) – The only quality parameter that exceeds the ADWG health limit is fluoride, which ranges from 5.5 to 6 mg/L (6 in the Snapshot Monitoring). This is precisely the feature that will be used for beneficial purposes by adding borewater at 10% to the treated river water to provide fluoride in the specified range of 0.6 to 0.8 mg/L (quarterly average).
 
 

“Fluoride occurs naturally in seawater (1.4 mg/L), soil (up to 300 parts per million) and air (from volcanic gases and industrial pollution). Naturally occurring fluoride concentrations in drinking water depend on the type of soil and rock through which the water drains. Generally, concentrations in surface water are relatively low (<0.1–0.5 mg/L), while water from deeper wells may have quite high concentrations (1–10 mg/L) if the rock formations are fluoride-rich.” 2011 ADWG.

Longreach (Queensland) – Turbidity

2009-11: Longreach (Queensland) – Turbidity 10.5 NTU (Maximum detection during year), 1.99NTU av.

2015/16: Longreach (Queensland) – Turbidity 187 NTU (Maximum detection during year) (11.83NTU av.)

Longreach Regional Council Drinking Water Quality Management Plan 2015/16

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.

2011 Dec: Longreach (Queensland) – Chlorate

13 Dec 11: 0.75mg/L

Chlorite: ADWG Health 0.3mg/L.

Chlorite and chlorate are disinfection by-products of chlorine dioxide disinfection process.

“… industry are having serious problems meeting chlorite/chlorate limits that were proposed in the new Australian Drinking Water Guidelines, especially for disinfection in long distance pipelines that are dosed with sodium hyptochlorite” pers comm 18/5/11.

“Chlorite occurs in drinking water when chlorine dioxide is used for purification purposes. The
International Agency for Research on Cancer (IARC) has concluded that chlorite is not classifiable as carcinogenic to humans and is listed in the Group 3 category. Changes in red blood vessels due to oxidative stress are a major concern with excessive levels of Chlorite in drinking water. According to the US EPA, potential health problems for people drinking Chorite above safe drinking water guideline include: Anemia in infants and young children and nervous system effects.” https://water.epa.gov/drink/contaminants/index.cfm

“Chlorine dioxide (chlorite) is rarely used as a disinfectant in Australian reticulated supplies.
When used, the chlorite residual is generally maintained between 0.2mg/L and 0.4mg/L. It is
particularly effective inthe control of manganese-reducing bacteria. Few data are available on
chlorate levels in Australian water supplies….Chlorine dioxide, chlorite, and chlorate are all
absorbed rapidly by the gastrointestinal tract into blood plasma and distributed to the major
organs. All compounds appear to be rapidly metabolised. Chlorine dioxide has been shown to
impair neurobehavioural and neurological development in rats exposed before birth. Experimental studies with rats and monkeys exposed to chlorine dioxide in drinking water have shown some evidence of thyroid toxicity; however, because of the studies’ limitations, it is difficult to draw firm conclusions (WHO 2005) The primary concern with chlorite and chlorate is oxidative stress resulting in changes in red blood cells. This end point is seen in laboratory animals and, by analogy with chlorate, in humans exposed to high doses in poisoning incidents (WHO 2005).” Australian Drinking Water Guidelines – National Health and Medical Research Centre

“…Subchronic studies in animals (cats, mice, rats and monkeys) indicate that chlorite and chlorate cause haematological changes (osmotic fragility, oxidative stress, increase in mean corpuscular volume), stomach lesions and increased spleen and adrenal weights… Neurobehavioural effects (lowered auditory startle amplitude, decreased brain weight and decreased exploratory activity) are the most sensitive endpoints following oral exposure to chlorite…” https://www.hc-sc.gc.ca/ewh-semt/pubs/water-eau/chlorite-chlorate/indexeng.
php#sec10_1Guidelines for Canadian Drinking Water Quality.

Longreach (Queensland) – Trichloroacetic Acid

Breaches to ADWG listed only

2011 February 8: Longreach (Queensland) 104ug/L

2011 March 15: Longreach (Queensland) 109ug/L + 102ug/L

2012 February 29: Longreach (Queensland) 106ug/L

2012 April 3: Longreach (Queensland) 110ug/L

Australian Guidelines Trichloroacetic Acid 0.100mg/L, Dichloroacetic Acid 0.100mg/L

“Chloroacetic acids are produced in drinking water as by-products of the reaction between chlorine and naturally occurring humic and fulvic acids. Concentrations reported overseas range up to 0.16mg/L and are typically about half the chloroform concentration. The chloroacetic acids are used commercially as reagents or intermediates in the preparation of a wide variety of chemicals. Monochloroacetic acid can be used as a pre-emergent herbicide, dichloroacetic acid as an ingredient in some pharmaceutical products, and trichloroacetic acid as a herbicide, soil sterilant and antiseptic.” Australian Drinking Water Guidelines – National Health and Medical Research Council…

There are no epidemiological studies of TCA carcinogenicity in humans. Most of the human health data for chlorinated acetic acids concern components of complex mixtures of water disinfectant by-products. These complex mixtures of disinfectant by-products have been associated with increased potential for bladder, rectal, and colon cancer in humans [reviewed by Boorman et al. (1999); Mills et al. (1998)].” Ref: tmp/Trichloroacetic acid (TCA) CASRN 76-03-9 IRIS US EPA.htm

Longreach (Queensland) – Lead

15/8/11: Longreach Lead 0.0048mg/L (max)

Lead Guideline reduced from 0.01mg/L to 0.005mg/L in June 2025. “The concentration of lead in water within premises may be higher, especially in older buildings, due to contact of the water with lead-containing plumbing products (enHealth 2021). A review found several Australian and international studies that detected up to 0.162 mg/L of lead in drinking water due to leaching from lead-containing plumbing materials including taps and lead service lines, suggesting that leaching of lead from lead-containing plumbing materials can be substantial (SLR 2023)… Based on health considerations, the concentration of lead in drinking water should not exceed 0.005 mg/L.”

2009/16 – Longreach (Queensland) – E.coli, Fluoride, Turbidity, Chlorate, Trichloroacetic Acid, Lead

in , , , ,
2009 July – 2011 November – Longreach (Queensland) – E.coli
Number of samples 213. Max 9, Average 0.14
2014/15: No E.coli detected since January 2010. 7 samples above ADWG
Incident Description: Detection of E. coli in the reticulation system. Possible contamination of sample. In-house testing from the same sample point on the same day was clear and had free chlorine of 1.41. Water treatment plant operator also took sewerage samples on the same day and likely contaminated a sample bottle prior to reticulation sample being taken. Corrective and Preventative Actions: Three additional samples were taken one from the same sampling point, one from before and one from after on the same line. All samples came back clear of E. coli. The line was flushed and staff were retrained on sampling. Longreach Regional Council Drinking Water Quality Management DWQMP – Annual Report 30 June 2014 – 30 June 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 2011
2009/11 – Longreach (Queensland) – Fluoride
2009/11: Longreach (Queensland) – The only quality parameter that exceeds the ADWG health limit is fluoride, which ranges from 5.5 to 6 mg/L (6 in the Snapshot Monitoring). This is precisely the feature that will be used for beneficial purposes by adding borewater at 10% to the treated river water to provide fluoride in the specified range of 0.6 to 0.8 mg/L (quarterly average).
“Fluoride occurs naturally in seawater (1.4 mg/L), soil (up to 300 parts per million) and air (from volcanic gases and industrial pollution). Naturally occurring fluoride concentrations in drinking water depend on the type of soil and rock through which the water drains. Generally, concentrations in surface water are relatively low (<0.1–0.5 mg/L), while water from deeper wells may have quite high concentrations (1–10 mg/L) if the rock formations are fluoride-rich.” 2011 ADWG.
Longreach (Queensland) – Turbidity 2009-11: Longreach (Queensland) – Turbidity 10.5 NTU (Maximum detection during year), 1.99NTU av. 2015/16: Longreach (Queensland) – Turbidity 187 NTU (Maximum detection during year) (11.83NTU av.) Longreach Regional Council Drinking Water Quality Management Plan 2015/16 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. 2011 Dec: Longreach (Queensland) – Chlorate 13 Dec 11: 0.75mg/L Chlorite: ADWG Health 0.3mg/L. Chlorite and chlorate are disinfection by-products of chlorine dioxide disinfection process. “… industry are having serious problems meeting chlorite/chlorate limits that were proposed in the new Australian Drinking Water Guidelines, especially for disinfection in long distance pipelines that are dosed with sodium hyptochlorite” pers comm 18/5/11. “Chlorite occurs in drinking water when chlorine dioxide is used for purification purposes. The International Agency for Research on Cancer (IARC) has concluded that chlorite is not classifiable as carcinogenic to humans and is listed in the Group 3 category. Changes in red blood vessels due to oxidative stress are a major concern with excessive levels of Chlorite in drinking water. According to the US EPA, potential health problems for people drinking Chorite above safe drinking water guideline include: Anemia in infants and young children and nervous system effects.” https://water.epa.gov/drink/contaminants/index.cfm “Chlorine dioxide (chlorite) is rarely used as a disinfectant in Australian reticulated supplies. When used, the chlorite residual is generally maintained between 0.2mg/L and 0.4mg/L. It is particularly effective inthe control of manganese-reducing bacteria. Few data are available on chlorate levels in Australian water supplies….Chlorine dioxide, chlorite, and chlorate are all absorbed rapidly by the gastrointestinal tract into blood plasma and distributed to the major organs. All compounds appear to be rapidly metabolised. Chlorine dioxide has been shown to impair neurobehavioural and neurological development in rats exposed before birth. Experimental studies with rats and monkeys exposed to chlorine dioxide in drinking water have shown some evidence of thyroid toxicity; however, because of the studies’ limitations, it is difficult to draw firm conclusions (WHO 2005) The primary concern with chlorite and chlorate is oxidative stress resulting in changes in red blood cells. This end point is seen in laboratory animals and, by analogy with chlorate, in humans exposed to high doses in poisoning incidents (WHO 2005).” Australian Drinking Water Guidelines – National Health and Medical Research Centre “…Subchronic studies in animals (cats, mice, rats and monkeys) indicate that chlorite and chlorate cause haematological changes (osmotic fragility, oxidative stress, increase in mean corpuscular volume), stomach lesions and increased spleen and adrenal weights… Neurobehavioural effects (lowered auditory startle amplitude, decreased brain weight and decreased exploratory activity) are the most sensitive endpoints following oral exposure to chlorite…” https://www.hc-sc.gc.ca/ewh-semt/pubs/water-eau/chlorite-chlorate/indexeng. php#sec10_1Guidelines for Canadian Drinking Water Quality. Longreach (Queensland) – Trichloroacetic Acid Breaches to ADWG listed only 2011 February 8: Longreach (Queensland) 104ug/L 2011 March 15: Longreach (Queensland) 109ug/L + 102ug/L 2012 February 29: Longreach (Queensland) 106ug/L 2012 April 3: Longreach (Queensland) 110ug/L Australian Guidelines Trichloroacetic Acid 0.100mg/L, Dichloroacetic Acid 0.100mg/L “Chloroacetic acids are produced in drinking water as by-products of the reaction between chlorine and naturally occurring humic and fulvic acids. Concentrations reported overseas range up to 0.16mg/L and are typically about half the chloroform concentration. The chloroacetic acids are used commercially as reagents or intermediates in the preparation of a wide variety of chemicals. Monochloroacetic acid can be used as a pre-emergent herbicide, dichloroacetic acid as an ingredient in some pharmaceutical products, and trichloroacetic acid as a herbicide, soil sterilant and antiseptic.” Australian Drinking Water Guidelines – National Health and Medical Research Council… There are no epidemiological studies of TCA carcinogenicity in humans. Most of the human health data for chlorinated acetic acids concern components of complex mixtures of water disinfectant by-products. These complex mixtures of disinfectant by-products have been associated with increased potential for bladder, rectal, and colon cancer in humans [reviewed by Boorman et al. (1999); Mills et al. (1998)].” Ref: tmp/Trichloroacetic acid (TCA) CASRN 76-03-9 IRIS US EPA.htm Longreach (Queensland) – Lead 15/8/11: Longreach Lead 0.0048mg/L (max) Lead Guideline reduced from 0.01mg/L to 0.005mg/L in June 2025. “The concentration of lead in water within premises may be higher, especially in older buildings, due to contact of the water with lead-containing plumbing products (enHealth 2021). A review found several Australian and international studies that detected up to 0.162 mg/L of lead in drinking water due to leaching from lead-containing plumbing materials including taps and lead service lines, suggesting that leaching of lead from lead-containing plumbing materials can be substantial (SLR 2023)… Based on health considerations, the concentration of lead in drinking water should not exceed 0.005 mg/L.”