2012 January +2016/17: Belair (South Australia) – Trihalomethanes, Temperature

Belair (South Australia)

Breaches to Australian Drinking Water Guidelines Levels Only

18/01/2012 7:55 Belair Laffers Rd (School) Trihalomethanes – Total 254 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

Belair – South Australia – Temperature

January 11 2017: Belair (South Australia) Alta Mira Cr – Temperature 24C

February 8 2017: Belair (South Australia) Alta Mira Cr – Temperature 22C

February 22 2017: Belair (South Australia) Alta Mira Cr – Temperature 24C

March 8 2017: Belair (South Australia) Alta Mira Cr – Temperature 24C

March 22 2017: Belair (South Australia) Alta Mira Cr – Temperature 22C

April 24 2017: Belair (South Australia) Alta Mira Cr – Temperature 21C

 

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).