Much of the northern Basin is beginning 2021 with little reprieve from its prolonged dry period. This is despite drought-breaking rain in other parts of the Murray–Darling Basin over the past couple of months.
The MDBA head of River Management, Andrew Reynolds, said the whole of the Queensland part of the Basin remained drought declared, and northern and far-west regions of New South Wales were still waiting for significant rainfall to help replenish their river systems.
“The northern Basin’s water storage levels have started the year lower than we’d hoped, despite the influence of La Niña,” Mr Reynolds said.
“While the Basin storages as a whole are sitting on 54 per cent, the dams in the northern Basin are on 27 per cent.
“These water storage results demonstrate just how patchy rainfall has been – the Paroo, Moonie, Gwydir, Namoi, Peel and Castlereagh catchments have had minor to moderate inflows and sent unregulated flows into the Barwon River, including flows past Walgett. Yet cease-to-flow conditions are still occurring further downstream in the Darling River.
“Persistent above-average rainfall is needed to turn around this long-term drought.”
Areas that received a healthy flow early last year are once again struggling with no flow or disconnected river reaches. In response to the situation in the Barwon-Darling, the New South Wales Government has enacted the new Resumption of Flows rule which means water coming through cannot be taken by certain licence holders for irrigation until there is a period of improved flow past Wilcannia or good prospects of sustained flow at Bourke.
“Protecting water in this way for downstream communities and ecosystems strikes a balance with upstream needs to also access water,” Mr Reynolds said.
To help support stressed ecosystems, the Commonwealth Environmental Water Holder is delivering water into the upper Barwon River system from the Gwydir and Macintyre rivers as part of the Northern Waterhole Top-up.
Mr Reynolds said that in contrast with the north, most of the southern Basin has benefited from reasonable rain in the past few months, reflected in state water allocations that are up to 100 per cent in regions such as the Murrumbidgee and for some Victorian licences. Southern storages are 62 per cent of capacity, which is up from 37 per cent this time last year.
“Water quality issues continue to be a watchpoint for the MDBA and state agencies, due to the ongoing risk of hypoxic blackwater. We also encourage people to be alert to blue-green algae outbreaks, which have been occurring in several parts of the River Murray and in storages in Victoria and the northern Basin.”
For more on the current state of the Basin, see the latest Basin in Brief.