Yulara (Northern Territory) – Nitrate

2006/11: Yulara Nitrate 52mg/L

2015/16: Yulara Nitrate 42mg/L

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.

Yulara (Northern Territory) – pH (acidic)

2003/04: Yulara pH 6.5

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.