Horrocks –  Western Australia – Iron

2007/08: Horrocks (Western Australia)  – Iron 0.65mg/L (Highest level only)

2011/12 Horrocks (Western Australia) Iron 0.600mg/L (max), 0.265mg/L (av)

Based on aesthetic considerations (precipitation of iron from solution and taste),
the concentration of iron in drinking water should not exceed 0.3 mg/L.
No health-based guideline value has been set for iron.

Iron has a taste threshold of about 0.3 mg/L in water, and becomes objectionable above 3 mg/L. High iron concentrations give water an undesirable rust-brown appearance and can cause staining of laundry and plumbing fittings, fouling of ion-exchange softeners, and blockages in irrigation systems. Growths of iron bacteria, which concentrate iron, may cause taste and odour problems and lead to pipe restrictions, blockages and corrosion. ADWG 2011

Horrocks (Western Australia) – pH (acidic)

Average pH: 2007 July-2008 June: 6.27 pH units

Average pH: 2009 July-2010 June: 6.48 pH units

2011/12 Horrocks (Western Australia) pH 6.34 (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.

Horrocks – Western Australia – Total Dissolved Solids

2008/09: Horrocks (Western Australia) – Total Dissolved Solids 1260mg/L (max), 1210mg/L (mean)

2009/10: Horrocks (Western Australia) – Total Dissolved Solids 1200mg/L (max)

2010/11 Horrocks (Western Australia) Total Dissolved Solids 1215mg/L (max), 1187mg/L (av)

2011/12 Horrocks (Western Australia) Total Dissolved Solids 1182mg/L (max), 1174mg/L (av)

2013/14 Horrocks (Western Australia) Total Dissolved Solids 1327mg/L (max), 1289mg/L (av)

2014/15 Horrocks (Western Australia) Total Dissolved Solids 1357mg/L (max), 1303mg/L (mean)

2015/16 Horrocks (Western Australia) Total Dissolved Solids 1286mg/L (max), 1268mg/L (mean)

2016/17 Horrocks (Western Australia) Total Dissolved Solids 1358mg/L (max), 1318mg/L (mean)

2017/18 Horrocks (Western Australia) Total Dissolved Solids 1352mg/L (max), 1328mg/L (mean)

2018/19: Horrocks (Western Australia) Total Dissolved Solids 1407mg/L (max), 1347mg/L (mean)

2019/20: Horrocks (Western Australia)  Total Dissolved Solids 1341mg/L (max), 1325mg/L (mean)

2022/23: Horrocks (Western Australia)  Total Dissolved Solids 1323mg/L (max), 1310mg/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

Horrocks (Western Australia) – Chloride

2013/14 Horrocks (Western Australia) Chloride 610mg/L (max), 602mg/L (av)

2014/15 Horrocks (Western Australia) Chloride 615mg/L (max), 608mg/L (mean)

2015/16 Horrocks (Western Australia) Chloride 605mg/L (max), 594mg/L (mean)

2016/17 Horrocks (Western Australia) Chloride 620mg/L (max), 601mg/L (mean)

2017/18 Horrocks (Western Australia) Chloride 610mg/L (max), 593.8mg/L (mean)

2018/19: Horrocks (Western Australia) Chloride 620mg/L (max), 601mg/L (mean)

2019/20: Horrocks (Western Australia) Chloride 605mg/L (max), 601mg/L (mean)

2022/23: Horrocks (Western Australia) Chloride 605mg/L (max), 601mg/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