A stressed Murray cod from a waterhole in the Darling River presents with red lesions on its body (early April 2018). Image NSW DPI Fisheries.
In January 2018, over 1,000 km of the Barwon-Darling River downstream of Brewarrina ceased to flow. This happens from time to time. As a result, the water quality deteriorates in stagnant waterholes, and the instream life is put under significant stress.
Some rainfall in Queensland has been flowing into the Barwon-Darling throughout March 2018. A modest amount of water has partly replenished some of the drought refuge waterholes in the Barwon-Darling and some northern tributaries, but these flows have been not enough to complete the task or provide much connectivity between waterholes.
In response, between April and June 2018, Commonwealth and NSW water for the environment will be delivered to build on these natural inflows and provide for connectivity across multiple river systems to protect and support native fish.
Between 25 and 30 GL of environmental water will be used mainly from the Gwydir Valley and Border Rivers catchments.
Connecting the northern rivers will support at least five important native fish species, including threatened species such as silver perch and iconic Murray cod.
Murray cod being released after monitoring. Image CEWO.
It will help by providing better food sources and opportunities to disperse and either improve water quality in their stretch of the river or giving them the chance to find better habitat in neighbouring waterholes.
This flow event will help preserve these species for future generations of Australians.
It is a complex task to coordinate an environmental flow over 2,000 km of river, including the northern tributaries and the full length of the Barwon-Darling River to the Menindee Lakes.
NSW has provided significant support for this flow event including providing environmental water, technical advice, river information, and protecting the water so that it stays in the river channel to benefit the environment.
Extensive monitoring of flows, habitat condition, and fish response will be undertaken. The learnings will be shared with the community, and inform future use of water for the environment. This is an opportunity for the community to work with government to gain a better understanding of the river and the environment.
Communities in the north of the Basin from Goondiwindi and Moree to Bourke and onto Wilcannia can expect a healthier river as a result of flow events such as this.
As a result of the Basin Plan, we are able to help the river system to recover, bit by bit, through actions such as this.
This map shows the storages that water for the environment will be delivered from and when flows are expected to arrive at Wilcannia. Up to 23.8GL of Commonwealth environmental water and 7.2GL of NSW Government environmental water has been made available to connect the northern rivers.
For more information