Update of seasonal determinations and outlooks for 2020/21

Monday 3 August, 2020

The Resource Manager for northern Victoria today announced an update to the 2020/21 seasonal determinations.

The Murray system moves from 15 per cent of high-reliability water shares (HRWS) to 19 per cent HRWS.

The Bullarook system increases from 0 per cent HRWS to 5 per cent HRWS.

Seasonal determinations in the Goulburn, Broken, Campaspe and Loddon systems remain unchanged.

Resource Manager Mark Bailey said continued dry conditions during July after a dry June had slowed the water availability improvements seen in the previous three months.

“Rainfall in July was below average in the catchment areas,” Dr Bailey said.

“After a very dry June, the continued low rainfall meant streamflows slowed appreciably. 

“Flows into the major storages in the Goulburn, Broken, Campaspe and Loddon systems in the past fortnight were close to the estimates. That means we didn’t pick up more resource for allocation in these systems.

“Flows into the Murray system were enough to increase the seasonal determination by 4 per cent.

“The mid-river storages such as Waranga Basin in the Goulburn system and Lake Victoria in the Murray system are effectively full.

“Flows into Lake Eildon, Lake Hume and Dartmouth Dam plus any supply that is met from catchment flows will define seasonal determination improvements in the Goulburn and Murray systems over the next few months.”

 Dr Bailey said the latest Bureau of Meterology seasonal outlook still favours above-average rainfall across the catchment ares for the three month period from August to October.

“The outlooks for August and September do not favour wetter or drier conditions over the catchment areas," Dr Bailey said. 

“The Bureau’s El Niño–Southern Oscillation outlook remains at La Niña watch meaning the chance of a La Niña forming is around 50 per cent in late winter or early spring. La Niña events may support rainfall across southeast Australia.”

Dr Bailey advised entitlement holders to use the seasonal determination outlooks and weather information when planning their water needs in 2020/21.

The seasonal determinations for northern Victorian water systems on Monday 3 August are:

Water System High-Reliability Water Share Low-Reliability Water Share
Murray 19% 0%
Broken 30% 0%
Goulburn 37% 0%
Campaspe 40% 0%
Loddon 37% 0%
Bullarook 5% 0%

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 in the Victoria’s share of the both Hume and Dartmouth reservoirs below 50 per cent. The current risk of spill in the Murray system allows 200 GL of net trade from New South Wales to Victoria. Customers can find out more about trade adjustments on the Water Register website.

The Goulburn system’s inter-valley trade (IVT) account owes about 234 GL to the Murray system. The Goulburn, Campaspe and Loddon systems can trade to the Victorian Murray system, New South Wales and South Australia while the total volume owed to the Murray system is less than 200 GL.

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) is restricting trade of water allocations from above the Barmah Choke to downstream of the Choke 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 risk of spill in the Murray, Goulburn and Campaspe systems will be updated on Monday 10 August 2020.
  • The next 2020/21 seasonal determination announcement and outlook will be released on Monday 17 August 2020.