Water will be available to trade from above, to below, the Barmah Choke at the start of the 2019-20 irrigation year.
Murray-Darling River Management executive director Andrew Reynolds said the trade balance at the Barmah Choke on July 1 was expected to be just above 25 gigalitres.
The Barmah Choke is a naturally narrow part of the River Murray channel stretching from below Cobram in Victoria to just upstream of Echuca, Vic.
The choke restricts the flow in the river, which limits the volume of water that can be delivered over the season.
"Due to the restricted flow, there are rules to ensure water can be physically delivered downstream in the volumes needed," Mr Reynolds said.
"This means in normal circumstances the sale of water from upstream of the choke to buyers downstream can only happen once the same or a greater volume of water has been traded in the opposite direction first sending water from accounts owned downstream to those upstream of the choke.
The balance of trade starts each 'water year' at zero.
"It is then credited with savings transferred up to the Snowy Scheme from downstream of the choke," Mr Reynolds said.
"This year, that credit of 25GL will free up some trade to downstream buyers from the outset."
Mr Reynolds said the persistent dry conditions in the Murray River meant water users were keen to know about upcoming trading opportunities
The limit on trade across the choke was likely to remain for 2019-20, unless there were exceptional circumstances to warrant its relaxation.
"The assessment of water delivery through the choke is part of our planning for the year ahead, which involves consideration of factors including storage levels, state allocations, water demand, the climate and the amount of water held in the tributaries," he said.
"In the interests of transparency and a level playing field we are alerting the market now to the anticipated trading conditions.
"It is worth noting that the trade of water from below the choke to above the choke is always open, and trade applications should continue to be submitted to the relevant Basin state agencies."
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