Seasonal determination update for northern Victoria systems

Monday 15 August, 2022

The Resource Manager for northern Victoria today updated the seasonal determinations for 2022/23 water availability.

The Goulburn and Loddon systems increase from 76 per cent of high-reliability water shares (HRWS) to 93 per cent HWRS.

The Campaspe system moves from 77 per cent HRWS to 82 per cent HRWS. The Broken system increases from 46 per cent HRWS to 57 per cent HRWS.

The Bullarook system seasonal determination increases from 100 per cent HRWS and 40 per cent of low-reliability water shares (LRWS) to the maximum available 100 per cent HRWS and 100 per cent LRWS.

The Murray system seasonal determination remains unchanged at 100 per cent HWRS.

Resource Manager Mark Bailey said rainfall during the first half of August enabled the seasonal determination increases announced today.

“After a below-average July, this month’s rainfall has generated good streamflow responses in all catchments,” Dr Bailey said. “The Goulburn and Loddon systems have particularly profited from improved storage volumes.

“Another 1,040 gigalitres is needed in the Murray system before the reserves for HRWS in 2023/24 are secure and LRWS seasonal determinations can commence,” Dr Bailey added. “This volume will reduce when system operating requirements and demands are met without releasing water from storage.”

Dr Bailey confirmed the scale of the first deductions from Murray spillable water accounts this season following releases through July to manage Lake Hume close to the full supply level.

“A deduction of about 115 gigalitres will be made with today’s announcement,” Dr Bailey said. “This is about 27 per cent of the current volume held in the spillable accounts.

“As releases to manage the Lake Hume volume continue, Murray system entitlement holders should expect further deductions from spillable water accounts in the September 15 seasonal determination update.”

Dr Bailey said continued rainfall was likely, with longer term predictions favouring wetter conditions.

“The latest Bureau of Meteorology forecast suggests above-average rainfall will continue through to December,” Dr Bailey added.

The seasonal determinations for northern Victorian water systems on Monday, August 15 are: 

The seasonal determinations for northern Victorian water systems on Monday 15 August are:
Water System High-Reliability Water Share Low-Reliability Water Share
Murray 100% 0%
Broken 57% 0%
Goulburn 93% 0%
Campaspe 82% 0%
Loddon 93% 0%
Bullarook 100% 100%


Trading opportunities

Allocation trade from New South Wales to Victoria is limited to the lesser of a net annual volume of 200 GL or a volume that keeps the risk of spill from Victoria’s share of both Lake Hume and Dartmouth Reservoir below 50 per cent. Presently, allocation trade from New South Wales to Victoria is not possible because Victoria’s shares of Lake Hume and Dartmouth Reservoir are full. The opportunity for allocation trade is updated with each risk of spill announcement. Customers can learn more about trade opportunities and a trial of improved trade adjustment methods on the Victorian Water Register website

A new trade rule for trade from the Goulburn, Broken, Campaspe and Loddon systems to the Victorian Murray system, New South Wales and South Australia came into effect on July, 1 2022. Further trade opportunities will be announced in October and December based on seasonal conditions. From December, net trade will be capped.

The Goulburn, Campaspe and Loddon systems can trade from the Victorian Murray system, New South Wales and South Australia while the total volume owed to the Murray system is greater than zero.

Customers participating in the water trading market can monitor trade availability on the Water Register website,

The Murray-Darling Basin Authority (MDBA) has announced that trading of water allocations from above the Barmah Choke to downstream of the Choke is restricted to protect the delivery of downstream water entitlements. Customers can monitor trading opportunities across the Barmah Choke on the MDBA website

Upcoming Resource Manager Announcements

  • The next 2022/23 seasonal determination announcement will be released on Thursday September 1, 2022.
  • The risk of spill in the Murray, Goulburn and Campaspe systems will be updated on Monday September 12, 2022.