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

24/1/18 – McKinlay (Queensland) – Fluoride

24/1/18: • The township has readings around 1.45mg/L every month however some months see the level exceed the health guideline limit of 1.5mg/L
• McKinlay Township has an open incident with results to be reported every month

Fluoride

“Fluoride occurs naturally in seawater (1.4 mg/L), soil (up to 300 parts per million) and air (from volcanic gases and industrial pollution). Naturally occurring fluoride concentrations in drinking water depend on the type of soil and rock through which the water drains. Generally, concentrations in surface water are relatively low (<0.1–0.5 mg/L), while water from deeper wells may have quite high concentrations (1–10 mg/L) if the rock formations are fluoride-rich.” 2011 ADWG. Health Guideline: 1.5mg/L

2015/16 – McKinlay (Queensland) – Total Dissolved Solids

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.

2017/18 – McKinlay (Queensland) – Ammonia

Based on aesthetic considerations (corrosion of copper pipes and fittings), the concentration
of ammonia (measured as ammonia) in drinking water should not exceed 0.5 mg/L.
No health-based guideline value is set for ammonia.

“…Most uncontaminated source waters have ammonia concentrations below 0.2 mg/L. High concentrations (greater than 10 mg/L) have been reported where water is contaminated with animal waste. Ammonia is unlikely to be detected in chlorinated supplies as it reacts quickly with free chlorine. Ammonia in water can result in the corrosion of copper pipes and fittings, causing copper stains on sanitary ware. It is also a food source for some microorganisms, and can support nuisance growths of bacteria and algae, often with a resultant increase in the nitrite concentration.” ADWG 2011

McKinlay (Queensland) – pH (alkaline)

The McKinlay Township samples are just over the max aesthetic limit of 8.5

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.

When pH is below 6.5 or above 11, the water may corrode plumbing fittings and pipes. This, however, will depend on other factors such as the material used, the concentration and type of ions in solution, the availability of oxygen, and the water temperature. Under some conditions, particularly in the presence of strong oxidising agents such as chlorine, water with a pH between 6.5 and 7 can be quite corrosive.

Chlorine disinfection efficiency is impaired above pH 8.0, although the optimum pH for monochloramine disinfectant formation is between 8.0 and 8.4. In chloraminated supplies chlorine can react with ammonia to form odorous nitrogen trichloride below pH 7.

Chlorination of water supplies can decrease the pH, while it can be significantly raised by lime leached from new concrete tanks or from pipes lined with asbestos cement or cement mortar. Values of pH above 9.5 can cause a bitter taste in drinking water, and can irritate skin if the water is used for ablutions.

2017/18 – McKinlay (Queensland) – Sodium

McKinlay around 220mg/L