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Environmental flush to tackle algae in the lower Darling-Baaka

The NSW Government will begin delivering a flush of water from the upper Menindee Lakes through the lower Darling-Baaka River this week to help clear the current infestation of blue-green algae impacting local communities.

We know residents are worried and we have heard their concerns loud and clear which is why NSW is taking strong action to send up to 45-50 GL downstream.

The algal blooms have not budged in weeks, even as the weather has cooled down, and we don’t want to wait any longer because communities are suffering.

Basin Governments have worked quickly to fast track an innovative trial that will allow us to access environmental water to improve connectivity between the northern and southern Murray-Darling Basin which will also have the added benefit of helping to disperse the blue-green algae.

The environmental flush will see water moving along a 500 km stretch of the river which is expected to reach the bottom of the system in about a week’s time.

Thanks to heavy rainfall and fresh inflows from across the northern Basin, up to 225 GL of new, good quality water is arriving in Menindee Lakes currently and over the coming months which will mean the top lakes remain at full capacity regardless of this flush.

It is important to point out these releases will not have any impact on water allocations for downstream users because we are using additional water that is protected from extraction.

This trial has been in the works for some time and has been made possible with the full support of the Murray-Darling Basin Authority and the Commonwealth Environmental Water Holder.

NSW also appreciates the understanding and support provided by Victoria and South Australia in assisting to make this much needed release.

The NSW Government recognises that not only is the foul smell and colour of the water extremely distressing for the local community, blue-green algae can also pose potential health risks to humans and livestock.

It should be made clear that town water in Wentworth and Menindee remains safe to drink because it goes through a water treatment plant process.

However, the raw river water is not treated and is not safe to drink.

The advice from NSW Health to the community is not to drink water direct from the river, or to swim, bathe or eat fish in locations where there is a red alert in place.

Farmers in these areas are also being advised to keep their livestock off river water until conditions improve.

Importantly, dissolved oxygen levels are currently at safe levels for fish, and there have been no additional fish death events at this stage.

While the NSW Government is hoping that this environmental flush will help tackle the blue green algae problem, it is not guaranteed that it will work as there is no silver bullet in dealing with an event of this size and magnitude.

Understandably, the community is concerned, and rightly so. This is a complex issue that is not easy to fix but we have to give everything a go.

We will continue to keep the community informed via regular updates.

For more information go to: Northern to southern Basin environmental flow protection trial

Minister for Water Rose Jackson said:

“I want to reassure communities in the Far West that I have been listening to their concerns which is why I have been advocating strongly behind the scenes for this environmental flush to do whatever I can to get rid of the blue-green algae and improve water quality for local people.

“This has not been an easy task. But I am pleased that all the Basin states are onboard and bringing the trial forward will help reset the river and tackle this severe blue green algae problem.

“It has been over 12 months since I took the reins of this portfolio and from the outset, I have made every effort to put river health and the communities living along it front and centre.

“This includes instigating an independent inquiry by the Office of the Chief Scientist and Engineer into the 2023 fish deaths, ramping up river monitoring and increasing resources to improve the way we manage and respond to water quality issues.

“We need to use every tool at our disposal to try and get results and address this challenging blue-green algae event because it appears the cooler weather, which normally puts an end to algal blooms, is not having the effect it previously has.

“NSW has been on standby to start a connectivity trial including waiting for the right river conditions. With significant flows coming into the system, we feel this is a great opportunity to begin.”

Aerial view of river with brown water
Environmental flush to tackle algae in the lower Darling-Baaka