Water Quality

How is our water treated?

Water in Karangi Dam is treated by pumping air through a pipe into the bottom of the dam. The purpose of aeration is to:

• prevent water turning over (destratification)
• raise the dissolved oxygen level
• oxidise iron and manganese which settles out within the dam
• settle out suspended dirt particles or other matter within the dam

Water is then pumped from the dam where it is dosed with low levels of lime, this raises the alkalinity of the water, which prevents corrosion in copper and concrete pipes and reservoirs. At the same time CO2 is added to the water to lower the pH.

At the balance tank a low dose of chlorine is added to disinfect the water and eliminate disease-carrying bacteria. The end result is a safe product for all consumers, that meets the Australian Drinking Water Guidelines.

Is our water fluoridated?

Fluoride will be added to the Coffs Harbour town water supplies from November 2005.

How is our water tested?

Testing is carried out regularly at 32 different sites to ensure that drinking water is of good quality and meets the Australian Drinking Water Guidelines and Department of Health standards.

What do we test for?

Biological, Physical, Chemical and Radiological characteristics that may affect the quality of water are tested.

These water quality indicators can be categorised as:

• Micro Biological: bacteria, algae.
• Physical: temperature, turbidity, colour, dissolved solids, pH, dissolved oxygen, taste and odour.
• Chemical: Inorganic chemicals, including arsenic, chloride, copper, iron, lead, manganese, nitrate, nitrite, sodium, tin, zinc etc., organic compounds and disinfection by-products.
• Radiological: gross alpha and beta activity concentrations.

Do you require water testing?

Coffs Harbour Water has an Environmental Laboratory that provides commercial water testing services.

For further information, phone the laboratory on (02) 6648 4460 or fax on (02) 6648 4466.

What causes our water to become discoloured?

When there is a sudden increase in the rate of water flow through pipes or a change in direction, it is possible to stir up sediments that have settled in the pipes over a period of time. These sediments are then suspended in the water, giving it a discoloured appearance.

Although unsightly, the suspended particles that cause discoloured water are harmless to health. The sediment contains very fine iron and manganese particles.
Burst pipes can also result in discoloured water, due to the need to reverse water flow patterns in surrounding streets.

Water Flushing

The reticulation system is flushed on a regular basis to prevent a build up of minerals and particles in the pipes. Water in the system is not filtered as it currently meets appropriate water quality standards. Council is however investigating the installation of a water filtration plant to ensure higher water quality and to meet anticipated future guidelines.

Why does my water have a cloudy or milky appearance?

If you experience white, cloudy or milky looking water it is caused by air in the water, and it is harmless. It can occur when work is carried out on water mains (eg. a burst water main) or when a faulty air valve allows air to enter the water pipe. If you leave the water to stand in a glass for a short period it will allow the air bubbles to be released and the water will return to a clear appearance.

Do you have water quality problems?

If you have a dirty water problem check to see whether a regular water flushing program is underway by looking in the paper or listening to the radio.  If there's no program underway, try running a tap near the front of the property (closest to mains) for a couple of minutes to see if it clears. If it doesn't clear, call Coffs Harbour Water's 24-hour service on 6648 4000.

If the discolouration stains your washing, keep the articles immersed in water and call Coffs Harbour Water and we can deliver a cleaning agent to help remove stains from your washing.