This means people upstream of the choke can sell water to buyers downstream of the choke, but only if the same or greater volume of water has been transferred from downstream to upstream of the choke first.
MDBA River Management Executive Director David Dreverman said an assessment of current water resource and operational conditions has been done, and that carefully controlling the demand on channel capacity at the choke was needed for effective operation of the river.
"We've looked at how much water is moving through the system, we've done an estimate of future demand, and we've looked at how much trade is taking place," Mr Dreverman said.
"To protect the delivery through the choke of existing water entitlements from the primary storages at Hume and Dartmouth reservoirs, it's necessary to continue the restriction on trade.
"Water users are advised that the balance of water that can be traded through the choke will be reset on 1 July 2015. An annual adjustment will also be made to take account of water savings transferred to the Snowy scheme, resulting in an opening balance of 32,700 megalitres. This will be the initial volume available to be traded from above to below the Barmah Choke.
"We'll continue to monitor the River Murray system and will lift the restriction if conditions permit."
Trade applications will continue to be processed by basin states. In the first instance, water market participants should contact their state trading authority for more information.
The current trade balance for the choke can be found at mdba.gov.au/river-data/barmah-choke
ENDS
For more information, contact the MDBA Media office at media@mdba.gov.au or 02 6279 0141
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