Six potential options that could address the declining regulated flow through the Barmah-Millewa reach of the Murray River have been detailed in a report released today by the Murray-Darling Basin Authority (MDBA).
Sand visible at Fisherman's Bend, Murray River. Photo credit - Streamology Pty Ltd.
The Barmah-Millewa reach is the narrow section of river that runs through the Barmah-Millewa Forest near Echuca and Deniliquin in the mid-Murray region. Capacity through the Barmah-Millewa reach has been reduced from 11,300 megalitres per day in the 1980s to 9,200 megalitres per day today.
MDBA Executive Director of River Management Andrew Reynolds said the options had been identified and scoped as part of the Barmah-Millewa Feasibility Study, which was initiated at the request of Basin state governments.
"We have spent the past year investigating the cause of lower flows and changed river conditions in this important part of the Murray," Mr Reynolds said.
"This foundational work will support governments to be fully informed when they come to decide how they would like to progress at the end of 2022.
"Six options have been developed to safeguard water delivery downstream while ensuring the Barmah-Millewa section of river does not suffer further reduced volume of flow, environmental decline or cultural impact.
"This work has meant looking at the whole river system to assess each option's effectiveness and reliability, and its engineering and ecological viability.
We have collected and analysed new information to fully understand the movement and impact of the sand slug, which has seen an estimated 20 million cubic metres of sand settle on the riverbed between the Yarrawonga Weir and Picnic Point. That's about 13 Melbourne Cricket Grounds' full of sand, caused largely by former land-use practices and gold mining in the rivers and creeks upstream.
"To develop the options, we have drawn on independent scientific research as well as community knowledge and values. We are talking to local communities, First Nations groups, local food producers and councils to gather their perspective on how this problem could be solved."
The six options being explored are:
- Stabilising the banks to prevent further incursion of water into the Barmah-Millewa Forest
- Removing sand from key locations
- Changing the timing of water delivery to Lake Victoria-Tar-Ru to be better attuned to environmental watering events
- Using Goulburn-Murray Irrigation District infrastructure to deliver water downstream
- Using Murray Irrigation Limited system to deliver water through the Edward/Kolety-Wakool-Niemur river system
- Releasing water to the Murray River via the Murrumbidgee River through the Snowy Hydro scheme.
The options will be presented to governments in December 2022 for them to decide which options to investigate further or to proceed to a business case and formal community consultation.
The Barmah-Millewa Preliminary Scoping Report is available on the MDBA website: Barmah-Millewa Feasibility Study | Murray-Darling Basin Authority (mdba.gov.au)
