AlburyCity is aware of the ongoing situation with discoloured water in some households in the Albury local government area. We also completely understand that people are put off by discoloured water. There are several factors contributing to this issue: the recent hot weather, increases in water consumption and natural changes within Lake Hume. We’ve sought advice from NSW Health, who have said that the element causing the discolouration (manganese) is unlikely to cause health issues.
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Why is my water discoloured? keyboard_arrow_right
Your water is discoloured because of the presence of the naturally occurring elements iron and manganese in the pipe network.
Manganese builds up in water supply reservoirs and pipes over time. Even when it is present in treated water at very low levels, manganese can be further ‘oxidised’ by the chlorine in our town water to ‘drop out’ of the water as very fine sediment (manganese oxide).
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Is the water safe to drink? keyboard_arrow_right
NSW Health advises that manganese is unlikely to cause any health issues.
The Australian Drinking Water Guidelines values for manganese are as follows:
- Guideline health value – 0.5 mg/litre
- Guideline aesthetic value – 0.1 mg/litre
Council’s operational target value for manganese is 0.02 mg/litre
Ongoing testing confirms that water leaving the water treatment plant has not exceeded 0.05 mg/litre (10 times lower than the guideline health value).
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Where is the iron and manganese coming from? keyboard_arrow_right
Iron and manganese are present in Lake Hume as a result of the 2019-2020 bushfires, which saw large volumes of sediment and bushfire run-off enter the lake.
Large amounts of this sediment now sit on the bottom of the lake, near the dam wall.
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How is it getting into the town water supply? keyboard_arrow_right
The dam water being released into the river has been very cold, low in dissolved oxygen and high in manganese and iron.
AlburyCity’s water supply is sourced from the Murray River. As a result, the release of this water from the dam over time has meant that low levels of manganese have entered the pipes of our water systems.
Despite the treatment plants operating effectively to keep levels of manganese in the treated water well below Australian Drinking Water Guidelines (ADWG), manganese is now observable in the water supply to some of our community.
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What are you doing to fix the issue? keyboard_arrow_right
We have crews on the ground flushing mains in affected areas, and we’ve increased our water sampling and testing regimes within our city.
We’ve also negotiated with the dam operator, the Murray Darling Basin Authority, to change how water is being released from the dam.
These changes saw some of the water released occur over the top of dam wall to enable better aeration of the discharged waters.
By changing the combination of flows from Hume Dam, we have been able to improve the quality of the source water and reduce the levels of iron and manganese within our piped water network by 40%.
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Why aren't I seeing any change? keyboard_arrow_right
Although we’ve reduced the amount of manganese coming into the treatment plant, there is still an amount of residual manganese in the pipe network that is causing the discoloured water issue in households.
Unfortunately, there is no overnight fix for this situation. It will take some time for the manganese to be reduced within all our pipes across the city, but you can be assured that we are working hard to improve things for affected households.
It’s difficult to say how long the situation will last, but we are aiming to see gradual improvement over the coming weeks.
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What should I do in the meantime? keyboard_arrow_right
If you are experiencing dirty water:
- run an outside tap for five minutes or until it runs clear. A 5-minute flush will cost around 21c (household water costs $1.44 per 1,000 litres). It’s not ideal, and we know there are other pressures financially, but people should take comfort in the fact that it’s not a huge amount of money being used.
- Report discoloured water to us as soon as possible to arrange a water mains flush in the affected area.