Possible taste and odour to drinking water in Murray River towns
10 February 2021
North East Water is anticipating customers in Murray River towns may soon experience taste and odour in their drinking water due to the blue-green algae bloom developing in Lake Hume.
The bloom could enter the Murray River and flow downstream effecting the Wodonga, Bellbridge, Yarrawonga and Wahgunyah drinking water systems.
Executive Operations, John Day, said blue-green algae produces a naturally occurring compound called Geosmin in raw water.
“This Geosmin is the real culprit which can cause an earthy taste and odour in treated tap water”, Mr Day said.
“When the compound is at very high levels, it can be difficult for our treatment processes to remove all the taste and odour.
“Although the water may be unpleasant to taste, it is still safe to consume and meets all Australian Drinking Water Guidelines.
“We will use everything in our toolbox to treat this issue, including powdered activated carbon to help reduce the taste and odour.
“This process is generally quite effective at reducing the effects, however we are detecting higher concentrations of Geosmin than usual this year.”
Mr Day added, “It’s believed the current blue-green algae bloom in Lake Hume is caused by high levels of nutrients entering the system from catchments effected by last year’s bushfires.”
“The climate extremes we are now experiencing continue to push our treatment systems, and we will continue to monitor, adjust and trial different processes to help address the issue.
“Our customers in Tallangatta have been subjected to the same issue for several weeks now.
“I understand this is not an ideal situation and apologise to those who are affected.”
For more detail about blue-green algae and treated drinking water supplies visit www.newater.com.au/bga.
The Corporation sources water from Wodonga Creek (Murray River anabranch) to supply the towns of Wodonga, Baranduda, Barnawartha, Bonegilla, Chiltern, Ebden, Kiewa, Killara, Springhurst and Tangambalanga.
The Wahgunyah water treatment plant sources water from the Murray River and also supplies Rutherglen.
The Yarrawonga water treatment plant sources water from the Lake Mulwala and also supplies the towns of Bundalong, Tungamah, St James, Devenish and Goorambat.
*Blue-green alage near the Tallangatta raw water off-take.
* Satellite observation using Aquatic Plants and Algae Custom Script Detector (APA Script). The script allows to highlight aquatic plants and algae in lakes and lagoons. Applying the script, vegetation and algae in the water is displayed from turquoise colour to bright green and denser vegetation cover in bright yellow. In a second order of results, turbid water is also identified by the set of indices presented in the script and, thus, these areas with a large amount of sediment in suspension are painted in brown and red to purple colours.