Meekatharra (Western Australia) – Nitrate
2016/17 Meekatharra (Western Australia) Nitrate 70.28mg/L (max), 64.09mg/L av
2017/18 Meekatharra (Western Australia) Nitrate 67.32mg/L (max), 60.72mg/L (av)
2018/19: Meekatharra (Western Australia) Nitrate 65.6mg/L (max), 61.2mg/L (av.)
2019/20: Meekatharra (Western Australia) Nitrate 66.44mg/L (max), 62.04mg/L (av.)
“Cue, Meekatharra, Mount Magnet, New Norcia, Sandstone, Wiluna and Yalgoo have been granted an exemption from compliance with the nitrate guideline by the Department of Health. The water supplied is harmless to adults and children over the age of 3 months of age. Carers of infants younger than three months should seek advice from the Community Health Nurse regarding the use of alternative water sources for the preparation of bottle feeds. The Water Corporation provides bottled water free of charge for this purpose.” Water Corporation WA 2004/5 Annual Water Quality Report
“…According to the Water Corporation (2013) in 1996, the Western Australian Department of Heath exempted the following remote towns from meeting the water quality guidelines regarding excessive nitrate levels in drinking water: Cue, Meekatharra, Mount Magnet, Nabawa, New Norcia, Sandstone, Wiluna, Yalgoo, Laverton, Leonora, and Menzies. These exemptions are still current. Community health nurses are instructed to provide bottled water free to nursing mothers, at no cost…” Unsafe drinking water quality in remote Western
Australian Aboriginal communities Geographical Research 184 • May 2019 • 57(2), 178–188
Nitrate: ADWG Guideline 50mg/L. Nitrate is the product of oxygenated nitrogen created from the breakdown of organic matter; lightning strikes; inorganic pesticides; or explosives. The Australian Drinking Water Guidelines recommend that nitrate levels between 50-100mg/L are a health consideration for infants less than three months, although levels up to 100mg/L can be safely consumed by adults. Mainly a problem in Northern Territory and some communities in Western Australia.
Meekatharra – Western Australia – Hardness
2007/08: Meekatharra (Western Australia) – Hardness 287mg/L (Highest Detection Only)
2008/09: Meekatharra (Western Australia) – Hardness 280mg/L (max), 270mg/L (mean)
2010/11 Meekatharra (Western Australia) Hardness 290mg/L (max), 274mg/L (av)
2011/12 Meekatharra (Western Australia) Hardness 290mg/L (max), 275mg/L (av)
2013/14 Meekatharra (Western Australia) Hardness 300mg/L (max), 282mg/L (av)
2014/15 Meekatharra (Western Australia) Hardness 280mg/L (max), 278mg/L (mean)
2015/16 Meekatharra (Western Australia) Hardness 290mg/L (max), 283mg/L (mean)
2016/17 Meekatharra (Western Australia) Hardness 300mg/L (max), 290mg/L (mean)
2017/18 Meekatharra (Western Australia) Hardness 310mg/L (max), 292mg/L (mean)
2018/19: Meekatharra (Western Australia) Hardness 300mg/L (max), 288mg/L (mean)
2019/20: Meekatharra (Western Australia) Hardness 300mg/L (max), 285mg/L (mean)
GUIDELINE
“To minimise undesirable build‑up of scale in hot water systems, total hardness (as calcium
carbonate) in drinking water should not exceed 200 mg/L.
Hard water requires more soap than soft water to obtain a lather. It can also cause scale to form on hot water pipes and fittings. Hardness is caused primarily by the presence of calcium and magnesium ions, although other cations such as strontium, iron, manganese and barium can also contribute.”
Australian Drinking Water Guidelines 2011
Meekatharra – Western Australia – Total Dissolved Solids
2008/09: Meekatharra (Western Australia) – Total Dissolved Solids 1080mg/L (max), 1040mg/L (mean)
2009/10: Meekatharra (Western Australia) – Total Dissolved Solids 1083mg/L (max)
2010/11 Meekatharra (Western Australia) Total Dissolved Solids 1268mg/L (max), 1222mg/L (av)
2011/12 Meekatharra (Western Australia) Total Dissolved Solids 1071mg/L (max), 1046mg/L (av)
2013/14 Meekatharra (Western Australia) Total Dissolved Solids 1100mg/L (max), 1076mg/L (av)
2014/15 Meekatharra (Western Australia) Total Dissolved Solids 1075mg/L (max), 1064mg/L (mean)
2015/16 Meekatharra (Western Australia) Total Dissolved Solids 1071mg/L (max), 1066mg/L (mean)
2016/17 Meekatharra (Western Australia) Total Dissolved Solids 1083mg/L (max), 1069mg/L (mean)
2017/18 Meekatharra (Western Australia) Total Dissolved Solids 1090mg/L (max), 1068mg/L (mean)
2018/19: Meekatharra (Western Australia) Total Dissolved Solids 1078mg/L (max), 1059mg/L (mean)
2019/20: Meekatharra (Western Australia) Total Dissolved Solids 1071mg/L (max), 1053mg/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
Meekatharra (Western Australia) – Chloride
2013/14 Meekatharra (Western Australia) Chloride 305mg/L (max), 302mg/L (mean)
2014/15 Meekatharra (Western Australia) Chloride 310mg/L (max), 308mg/L (mean)
2015/16 Meekatharra (Western Australia) Chloride 310mg/L (max), 301mg/L (mean)
2016/17 Meekatharra (Western Australia) Chloride 305mg/L (max), 296mg/L (mean)
2017/18 Meekatharra (Western Australia) Chloride 325mg/L (max), 314mg/L (mean)
2018/19: Meekatharra (Western Australia) Chloride 300mg/L (max), 293mg/L (mean)
2019/20: Meekatharra (Western Australia) Chloride 290mg/L (max), 286mg/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
Meekatharra (Western Australia) – Sodium
2013/14 Meekatharra (Western Australia) Sodium 215mg/L (max), 204mg/L (av)
2014/15 Meekatharra (Western Australia) Sodium 195mg/L (max), 195mg/L (mean)
2015/16 Meekatharra (Western Australia) Sodium 205mg/L (max), 204mg/L (mean)
2016/17 Meekatharra (Western Australia) Sodium 210mg/L (max), 204mg/L (mean)
2017/18 Meekatharra (Western Australia) Sodium 210mg/L (max), 204mg/L (mean)
2018/19: Meekatharra (Western Australia) Sodium 210mg/L (max), 201mg/L (mean)
2019/20: Meekatharra (Western Australia) Sodium 205mg/L (max), 201.3mg/L (mean)
should not exceed 180 mg/L….The sodium ion is widespread in water due to the high solubility of sodium salts and the abundance of mineral deposits. Near coastal areas, windborne sea spray can make an important contribution either by fallout onto land surfaces where it can drain to drinking water sources, or from washout by rain. Apart from saline intrusion and natural contamination, water treatment chemicals, domestic water softeners and
sewage effluent can contribute to the sodium content of drinking water.” ADWG 2011
Meekatharra (South Australia) – Silica
2013/14 Meekatharra (Western Australia) Silica 80mg/L (max), 77mg/L (av)
2015/16 Meekatharra (Western Australia) Silica 80mg/L (max), 77mg/L (mean)
2016/17 Meekatharra (Western Australia) Silica 80mg/L (max), 78.8mg/L (av)
2017/18 Meekatharra (Western Australia) Silica 80mg/L (max), 78mg/L (av)
To minimise an undesirable scale build up on surfaces, silica (SiO2) within drinking waters should not exceed 80 mg/L.
GENERAL DESCRIPTION
Silica present in water is usually referred to as amorphous silica (i.e. lacking any crystalline structure). When silica is dissolved within water it forms monosilicic acid:
SiO2 + 2H2O à Si(OH)4
When the concentrations of monosilicic acid increase, polymerisation of the silica occurs, forming polysilicic acids followed by formation of colloidal silica. Monosilicic acid and polysilicic acids are the forms of silica analysed when determining dissolved silica content.
The deposition of silica from solutions can occur via various mechanisms. The deposition of silica that can cause the most problems for the water industry is via silica’s ability to deposit on solid surfaces that have hydroxyl (OH) groups present. Surfaces that commonly have hydroxyl groups present are glass and metallic surfaces. For example, dissolved silica will react with the surfaces of glass and begin to form a white precipitate. The silica forms silicates on the surface, resulting in silica build-up. In cases where customer complaints occur due to scale build-up, water hardness and silica concentrations should be investigated to determine the cause.
Silica can be a problem in water treatment due to its ability to cause fouling of reverse osmosis (RO) membranes (Sheikholeslami and Tan, 1999, Ning 2002, Sahachaiyunta and Sheikholeslami 2002). This occurs when the dissolved silica of the concentrate becomes super-saturated, causing silicates to form in the presence of metals, and these deposit on the membrane surface. The silicate then dehydrates, forming hard layers on the membrane that reduce the effectiveness of the process… 2011 ADWG
2014/15: Meekatharra (Victoria) Iron
2014/15 Meekatharra (Western Australia) Iron 80mg/L (max), 76mg/L (mean)
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