MDBA Barmah Choke feasibility study should be completed by the end of the year

The Barmah Choke is a narrow section of the Murray River, where it runs through the Barmah-Millewa Forest restricting water flow to around 7000 megalitres a day.

"We are looking at options as to how we manage getting water through the Choke and downstream," acting MDBA chief executive Andrew Reynolds said.

The MDBA had held several community engagement sessions on what it's called Capacity and Shortfall Projects, underway in the Barmah-Millewa reach and along the river.

"We are expecting to have the feasibility study done by the end of the calendar year," Mr Reynolds said.

"We are certainly trying to capture community views then we will make recommendations to the Ministerial Council about what we think are the relative merits of what the options are and how a package might come together."

The MDBA would then seek guidance from the state and federal Water Ministers as to which of the options they would like to see developed, in more detail, through a business case and implementation process.

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The MDBA says its research has shown land-use changes - in particular gold-mining, and land clearing along with desnagging and river regulation - was responsible for introducing large volumes of sediment to the river over a short period of time.

"One of the options could be to move some of the sand from the river, certainly we are not going to remove all the sand, there is way too much to contemplate completely removing it all," Mr Reynolds said.

"Localised, targeted effort, either in the locations where the biggest build up is and the capacity has been reduced the most might help, and also looking at the upstream end of the Choke, potentially removing more sand to stop more moving into the area where the congestion is greatest."

He said that would be a challenging option, as there were a lot of sensitive cultural and environmental values, associated with the Choke.

The MDBA was still at the early stages of the proposal, if, indeed, it became part of the final resolution of the issue, he said.

Investigations also centred on what to do with the sand, dredged from the river, as well as recreational and environmental issues.

"We think some localised activity could be very beneficial, in terms of managing the capacity of the river, but we don't underestimate those challenges," M Reynolds said.

There were a number of other options on the table: to stabilise the riverbank, moving water through the Murray Irrigation Limited (MIL) or Goulburn River systems, the time of transfers of water from the Hume Dam to Lake Victoria, SA, or using the Snowy River scheme and Murrumbidgee systems.

Riverbank stabilisation would stop further sand from entering the river, but would not reinstate lost capacity.

The MDBA was also examining capacity in the MIL and Goulburn systems and where the water would reenter the Murray.

"They may have a lower impact on the river itself, but are quite significant in the works that need to be done in those irrigation systems to make a meaningful difference," he said.

There was also a trade-off in changing the transfer of water, from Lake Hume to SA, he said, and there were concerns about delivery issues in the Murrumbidgee system.

"The solution is unlikely to be a single thing," he said.

"It's likely to be a suite of things, they will all contribute a bit and in different circumstances," he said.

"In different years, different things might be better."