2003/17: Daly Waters (Northern Territory). E.coli, Selenium, Chloride, Hardness, Total Dissolved Solids, Sodium, Iodine, Iron

2008/9: Daly Waters (Northern Territory) – E.coli

2003/4: E coli (org/ 100ml) 4 total exceedances. 91.3% samples passing reporting level.

2006/7: Daly Waters E.coli  1 exceedances. 97.4% samples passing reporting level.

2008/9: Daly Waters (Northern Territory) 2 exceedances. 92.9% samples passing reporting level.

Thermotolerant coliforms are a sub-group of coliforms that are able to grow at 44.5 ± 0.2°C. E. coli is the most common thermotolerant coliform present in faeces and is regarded as the most specific indicator of recent faecal contamination because generally it is not capable of growth in the environment. In contrast, some other thermotolerant coliforms (including strains of Klebsiella, Citrobacter and Enterobacter) are able to grow in the environment and their presence is not necessarily related to faecal contamination. While tests for thermotolerant coliforms can be simpler than for E. coli, E. coli is considered a superior indicator for detecting faecal contamination…” ADWG

Daly Waters (Northern Territory) – Selenium

2004/5: 0.01mg/L Daly Waters

2005/6: 0.012mg/L Daly Waters

2006/7: 0.012mg/L Daly Waters & Mataranka

2007/08: Daly Waters Selenium 0.01mg/L

2008/09: Daly Waters Selenium 0.01mg/L

2009/10: Daly Waters Selenium 0.008mg/L

Selenium: ADWG Guideline 0.01mg/L. An element and non-metal mainly found in sulphide ores such as pyrite. 50% of selenium used in the world, is for glass production. “Selenium and selenium salts are widespread in the environment. Selenium is released from natural and human-made sources, with the main source being the burning of coal. Selenium is also a by-product of the processing of sulfide ores, chiefly in the copper refining industry. The major use of selenium is in the manufacture of electronic components. It is used in several other industries, and selenium compounds are used in some insecticides, in hair shampoos as an anti-dandruff agent, and as a nutritional feed additive for poultry and livestock.” ADWG 2011

Daly Waters (Northern Territory) – Chloride

2003/04: Daly Waters Chloride 350mg/L

2004/05: Daly Waters Chloride 330mg/L

2005/06: Daly Waters  Chloride 334mg/L

2007/08: Daly Waters Chloride 348mg/L

2008/09: Daly Waters  Chloride 346mg/L

2009/10: Daly Waters Chloride 342mg/L

2010/11: Daly Waters Chloride 358mg/L

2011/12: Daly Waters Chloride 347mg/L

2012/13: Daly Waters Chloride 297mg/L

2014/15: Daly Waters Chloride 255mg/L

2015/16: Daly Waters Chloride 275mg/L

2016/17: Daly Waters Chloride 277mg/L

“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

Daly Waters – Northern Territory – Hardness

2003/04: Daly Waters Hardness 550mg/L

2004/05: Daly Waters  Hardness 550mg/L

2005/06: Daly Waters  Hardness 547mg/L

2006/07: Daly Waters Hardness 587mgL

2007/08: Daly Waters Hardness 587mg/L

2008/09: Daly Waters Hardness 580mg/L

2009/10: Daly Waters Hardness 528mg/L

2010/11: Daly Waters Hardness 526mg/L

2011/12: Daly Waters Hardness 517mg/L

2012/13: Daly Waters Hardness 501mg/L

2013/14: Daly Waters Hardness 505mg/L

2014/15: Daly Waters Hardness 516mg/L

2015/16: Daly Waters Hardness 562mg/L

2016/17: Daly Waters Hardness 549mg/L


“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

Daly Waters – Northern Territory – Total Dissolved Solids

2004/05: Daly Waters  Total Dissolved Solids 1292 mg/L

2005/06: Daly Waters  Total Dissolved Solids 1304 mg/L

2006/07: Daly Waters Total Dissolved Solids 1320mg/L

2007/08: Daly Waters Total Dissolved Solids 1339mg/L

2008/09: Daly Waters  Total Dissolved Solids 1337 mg/L

2009/10: Daly Waters Total Dissolved Solids 1321mg/L

2010/11: Daly Waters Total Dissolved Solids 1310mg/L

2011/12: Daly Waters Total Dissolved Solids 1297mg/L

2012/13: Daly Waters Total Dissolved Solids 1300mg/L

2013/14: Daly Waters Total Dissolved Solids 953mg/L

2014/15: Daly Waters Total Dissolved Solids 1018mg/L

2015/16: Daly Waters Total Dissolved Solids 1075mg/L

2016/17: Daly Waters Total Dissolved Solids 1150mg/L


“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

Daly Waters (Northern Territory) – Sodium

2003/4: Daly Waters Sodium 230mg/L

2004/05:  Daly Waters Sodium 221mg/L

2006/07: Daly Waters Sodium 222mg/L

2007/08: Daly Waters Sodium 218mg/L

2008/09:  Daly Waters Sodium 215mg/L

2009/10 Daly Waters Sodium 216mg/L

2010/11: Daly Waters Sodium 215mg/L

2011/12: Daly Waters Sodium 213mg/L

2012/13: Daly Waters Sodium 211mg/L

2016/17: Daly Waters Sodium 199mg/L

“Based on aesthetic considerations (taste), the concentration of sodium in drinking water
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

Daly Waters – (Northern Territory) – Iodine

2006/07: Daly Waters Iodine 0.262mg/L

2007/08: Daly Waters Iodine 0.26mg/L

2008/09: Daly Waters  Iodide 0.27mg/L

2009/10: Daly Waters Iodine 0.25mg/L

2010/11: Daly Waters Iodine 0.25mg/L

Daly Waters (Northern Territory) Iron

2016/17 Daly Waters Iron 0.36mg/L

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