2000/02 + 2011/12 +2016/17: Blanchetown (South Australia) – Trihalomethanes, Chloral Hydrate, Dichloroacetic Acid, Chlorate, Temperature

Blanchetown (South Australia)

Breaches to Australian Drinking Water Guidelines Levels Only

14/11/2000 Blanchetown Trihalomethanes – Total 321 ug/L

12/12/2000 Blanchetown Trihalomethanes – Total 341 ug/L

9/01/2001 Blanchetown Trihalomethanes – Total 470 ug/L

13/02/2001 Blanchetown Trihalomethanes – Total 387 ug/L

13/03/2001 Blanchetown Trihalomethanes – Total 342 ug/L

10/04/2001 Blanchetown Trihalomethanes – Total 302 ug/L

15/05/2001 Blanchetown Trihalomethanes – Total 264 ug/L

12/03/2002 Blanchetown Trihalomethanes – Total 266 ug/L

14/05/2002 Blanchetown Trihalomethanes – Total 277 ug/L

19/01/2011 Blanchetown Trihalomethanes – Total 262 ug/L

8/02/2011 Blanchetown Trihalomethanes – Total 384 ug/L

9/03/2011 Blanchetown Trihalomethanes – Total 354 ug/L

14/12/2016 Blanchetown Trihalomethanes – Total 282 ug/L

11/1/2017 Blanchetown Trihalomethanes – Total 282 ug/L

Trihalomethanes Australian Guideline Level 250μg/L (0.25mg/L)

Why and how are THMs formed?
“When chlorine is added to water with organic material, such as algae, river weeds, and decaying leaves, THMs are formed. Residual chlorine molecules react with this harmless organic material to form a group of chlorinated chemical compounds, THMs. They are tasteless and odourless, but harmful and potentially toxic. The quantity of by-products formed is determined by several factors, such as the amount and type of organic material present in water, temperature, pH, chlorine dosage, contact time available for chlorine, and bromide concentration in the water. The organic matter in water mainly consists of a) humic substance, which is the organic portion of soil that remains after prolonged microbial decomposition formed by the decay of leaves, wood, and other vegetable matter; and b) fulvic acid, which is a water soluble substance of low molecular weight that is derived from humus”. Source: http://water.epa.gov/drink/contaminants/index.cfm

Blanchetown (South Australia) – Chloral Hydrate

27/6/12 Blanchetown  Chloral Hydrate 21.4ug/L

Chloral hydrate is a disinfection by-product, arising from chlorination of water containing naturally occurring organic material (NOM). Chloral hydrate is a sedative and hypnotic drug. Long-term use of chloral hydrate is associated with a rapid development of tolerance to its effects and possible addiction as well as adverse effects including rashes, gastric
discomfort and severe renal, cardiac and hepatic failure.

2004 Australian Drinking Water Guideline: Trichloroacetaldehyde (chloral hydrate): 0.02mg/L

2011 Australian Drinking Water Guideline: Trichloroacetaldehyde (chloral hydrate): 0.1mg/L

Blanchetown (South Australia) – Dichloroacetic Acid

September 21 2016 Blanchetown (South Australia) – Dichoroacetic Acid 104ug/L

Australian Guideline Level: 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

2016/17: Blanchetown (South Australia) – Chlorate

10/8/16: Blanchetown (South Australia) – Chlorate 0.35mg/L

16/11/16: Blanchetown (South Australia) – Chlorate 1.7mg/L

22/2/17: Blanchetown (South Australia) – Chlorate 0.45mg/L

17/5/17: Blanchetown (South Australia) – Chlorate 0.4mg/L

Incident Description: The first non-compliance was a detection of chlorate from a routine sample taken from the Jericho Water Treatment Plant and the Alpha Water Treatment Plant. As Chlorate is a parameter with no reporting limit, any detection is reported immediately to the Department and results are monitored monthly. Corrective and Preventative Actions: Council are conducting further investigations into how to minimise chlorate occurrences, by looking to delivery methods and storage of chemicals.

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.” http://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…” http://www.hc-sc.gc.ca/ewh-semt/pubs/water-eau/chlorite-chlorate/indexeng.
php#sec10_1Guidelines for Canadian Drinking Water Quality.

Blanchetown – South Australia – Temperature

November 9 2016: Blanchetown (South Australia) – Temperature 21C

November 23 2016: Blanchetown (South Australia) – Temperature 22C

November 30 2016: Blanchetown (South Australia) – Temperature 22C

December 7 2016: Blanchetown (South Australia) – Temperature 23C

December 14 2016: Blanchetown (South Australia) – Temperature 24C

December 21 2016: Blanchetown (South Australia) – Temperature 23C

December 28 2016: Blanchetown (South Australia) – Temperature 26C

January 4 2017: Blanchetown (South Australia) – Temperature 27C

January 11 2017: Blanchetown (South Australia) – Temperature 28C

January 18 2017: Blanchetown (South Australia) – Temperature 27C

January 24 2017: Blanchetown (South Australia) – Temperature 28C

February 1 2017: Blanchetown (South Australia) – Temperature 27C

February 8 2017: Blanchetown (South Australia) – Temperature 27C

February 15 2017: Blanchetown (South Australia) – Temperature 27C

February 22 2017: Blanchetown (South Australia) – Temperature 25C

March 1 2017: Blanchetown (South Australia) – Temperature 27C

March 8 2017: Blanchetown (South Australia) – Temperature 25C

March 15 2017: Blanchetown (South Australia) – Temperature 25C

March 22 2017: Blanchetown (South Australia) – Temperature 26C

March 29 2017: Blanchetown (South Australia) – Temperature 24C

April 5 2017: Blanchetown (South Australia) – Temperature 23C

April 12 2017: Blanchetown (South Australia) – Temperature 20C

April 19 2017: Blanchetown (South Australia) – Temperature 21C

April 26 2017: Blanchetown (South Australia) – Temperature 21C


“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

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).