Latham (Western Australia) – pH (alkaline)

Average pH: 2008 July-2009 June: 8.79 pH units

Average pH: 2009 July-2010 June: 8.76 pH units

2010/11 Latham (Western Australia) pH 8.81 (av)

2013/14 Latham (Western Australia) pH 8.91 (av)

2014/15 Latham (Western Australia) pH 9.09 (av)

2015/16 Latham (Western Australia) pH 9.11 (av)

2016/17 Latham (Western Australia) pH 8.97 (av)

2017/18 Latham (Western Australia) pH 9.04 (av)

2018/19: Latham (Western Australia) pH 9.02 (av)

2019/20: Latham (Western Australia) pH 9.14 (av)

2022/23: Latham (Western Australia) pH 9 (av)

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.

Latham – Western Australia – Total Dissolved Solids

2008/09: Latham (Western Australia) – Total Dissolved Solids 665mg/L (max), 656mg/L (mean)

2009/10: Latham (Western Australia) – Total Dissolved Solids 661mg/L (max)

2010/11 Latham (Western Australia) Total Dissolved Solids 646mg/L (max), 646mg/L (mean)

2011/12 Latham (Western Australia) Total Dissolved Solids 664mg/L (max), 652mg/L (mean)

2013/14 Latham (Western Australia) Total Dissolved Solids 642mg/L (max), 642mg/L (mean)

2014/15 Latham (Western Australia) Total Dissolved Solids 647mg/L (max), 645mg/L (mean)

2015/16 Latham (Western Australia) Total Dissolved Solids 691mg/L (max), 674mg/L (mean)

2017/18 Latham (Western Australia) Total Dissolved Solids 707mg/L (max), 687mg/L (mean)

2018/19: Latham (Western Australia) Total Dissolved Solids 687mg/L (max), 673mg/L (mean)

2019/20: Latham (Western Australia)Total Dissolved Solids 696mg/L (max), 696mg/L (mean)

2022/23: Latham (Western Australia)Total Dissolved Solids 791mg/L (max), 746mg/L (mean)

GUIDELINE

“No specific health guideline value is provided for total dissolved solids (TDS), as there are no
health effects directly attributable to TDS. However for good palatability total dissolved solids
in drinking water should not exceed 600 mg/L.

Total dissolved solids (TDS) consist of inorganic salts and small amounts of organic matter that are dissolved in water. Clay particles, colloidal iron and manganese oxides and silica, fine enough to pass through a 0.45 micron filter membrane can also contribute to total dissolved solids.

Total dissolved solids comprise: sodium, potassium, calcium, magnesium, chloride, sulfate, bicarbonate, carbonate, silica, organic matter, fluoride, iron, manganese, nitrate, nitrite and phosphates…” Australian Drinking Water Guidelines 2011

Latham (Western Australia) – Chloride

2013/14 Latham (Western Australia) Chloride 305mg/L (max), 298mg/L (av)

2014/15 Latham (Western Australia) Chloride 295mg/L (max), 293mg/L (mean)

2015/16 Latham (Western Australia) Chloride 315mg/L (max), 310mg/L (mean)

2016/17 Latham (Western Australia) Chloride 305mg/L (max), 300mg/L (mean)

2017/18 Latham (Western Australia) Chloride 325mg/L (max), 307.5mg/L (mean)

2018/19: Latham (Western Australia) Chloride 310mg/L (max), 303mg/L (mean)

2019/20: Latham (Western Australia) Chloride 325mg/L (max), 318mg/L (mean)

2022/23: Latham (Western Australia) Chloride 325mg/L (max), 316mg/L (mean)

“Chloride is present in natural waters from the dissolution of salt deposits, and contamination from effluent disposal. Sodium chloride is widely used in the production of industrial chemicals such as caustic soda, chlorine, and sodium chlorite and hypochlorite. Potassium chloride is used in the production of fertilisers.

The taste threshold of chloride in water is dependent on the associated cation but is in the range 200–300 mg/L. The chloride content of water can affect corrosion of pipes and fittings. It can also affect the solubility of metal ions.

In surface water, the concentration of chloride is usually less than 100 mg/L and frequently below 10 mg/L. Groundwater can have higher concentrations, particularly if there is salt water intrusion.

Based on aesthetic considerations, the chloride concentration in drinking water should not exceed 250 mg/L.

No health-based guideline value is proposed for chloride.” 2011 Australian Drinking Water Guidelines