Paringa (South Australia) – Trihalomethanes

Breaches to Australian Drinking Water Guidelines Levels Only

13/04/2010 Paringa Lindsay Point Rd (outside Council Depot) Trihalomethanes – Total 297 ug/L

26/10/2010 Paringa Lindsay Point Rd (outside Council Depot) Trihalomethanes – Total 319 ug/L

21/12/2010 Paringa Lindsay Point Rd (outside Council Depot) Trihalomethanes – Total 294 ug/L

18/01/2011 Paringa Lindsay Point Rd (outside Council Depot) Trihalomethanes – Total 457 ug/L

15/02/2011 Paringa Lindsay Point Rd (outside Council Depot) Trihalomethanes – Total 406 ug/L

15/03/2011 Paringa Lindsay Point Rd (outside Council Depot) Trihalomethanes – Total 435 ug/L

22/11/2011 Paringa Lindsay Point Rd (outside Council Depot) Trihalomethanes – Total 287 ug/L

20/12/2011 Paringa Lindsay Point Rd (outside Council Depot) Trihalomethanes – Total 286 ug/L

14/02/2012 Paringa Lindsay Point Rd (outside Council Depot) Trihalomethanes – Total 280 ug/L

13/03/2012 Paringa Lindsay Point Rd (outside Council Depot) Trihalomethanes – Total 368 ug/L

22/01/2013 Paringa Lindsay Point Rd (outside Council Depot) Trihalomethanes – Total 251 ug/L

25/02/2014 Paringa Lindsay Point Rd (outside Council Depot) Trihalomethanes – Total 278 ug/L

1/11/2016 Paringa Lindsay Point Rd (outside Council Depot) Trihalomethanes – Total 256 ug/L

29/11/2016 Paringa Lindsay Point Rd (outside Council Depot) Trihalomethanes – Total 340 ug/L

21/2/2017 Paringa Lindsay Point Rd (outside Council Depot) Trihalomethanes – Total 255 ug/L

8/3/22: Paringa Lindsay Point Rd Trihalomethanes 272ug/L (max) 176.5ug/L (av. 2021/22)

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: https://water.epa.gov/drink/contaminants/in

Paringa (South Australia) – pH (alkaline)

2019/20: Paringa (South Australia) pH (average) 8.75pH units

Based on the need to reduce corrosion and encrustation in pipes and fittings, the pH of
drinking water should be between 6.5 and 8.5.

New concrete tanks and cement-mortar lined pipes can significantly increase pH and
a value up to 9.2 may be tolerated, provided monitoring indicates no deterioration in
microbiological quality.

pH is a measure of the hydrogen ion concentration of water. It is measured on a logarithmic scale from 0 to 14. A pH of 7 is neutral, greater than 7 is alkaline, and less than 7 is acidic.

One of the major objectives in controlling pH is to minimise corrosion and encrustation in pipes and fittings. Corrosion can be reduced by the formation of a protective layer of calcium carbonate on the inside of the pipe or fitting, and the formation of this layer is affected by pH, temperature, the availability of calcium (hardness) and carbon dioxide. If the water is too alkaline (above pH 8.5), the rapid deposition and build-up of calcium carbonate that can result may eventually block the pipe.

Paringa (South Australia) – Total Haloacetic Acid

2/11/21: Paringa (South Australia) Total Haloacetic Acid (HAA 9) 161ug/L (max) 135.5ug/L (av.)

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…