2019/2020 Seasonal Determination Outlook

Friday 15 February, 2019

Northen Victorian Resource Manager releases 2019/20 seasonal determination outlook

The Resource Manager for northern Victorian water systems today released the first outlook for 2019/20 seasonal determinations.

Northern Victorian Resource Manager Mark Bailey said seasonal determinations against high-reliability water shares (HRWS) at the start of the 2019/20 water year will depend heavily on flows received into the major storages during autumn and early winter.

“There are lower reserves in the storages compared to the reserves at this time in the last two water years. Unless we see an increase in the storage volumes, opening seasonal determinations are likely to be low,” Dr Bailey said.

“A repeat of the flows into the major storages observed in 2018/19 would result in the Goulburn system reaching about 65 per cent HRWS in February 2020 and the Murray system would be about 60 per cent.

“Early season announcements in the Broken and Bullarook systems will be influenced by the volume carried over and catchment conditions. Both systems are likely to start at 0 per cent HRWS."

“Carryover will be deliverable under all scenarios in the Murray, Goulburn, Campaspe and Loddon systems. At this stage of the year there is currently insufficient water to operate the Broken and Bullarook systems as usual for the entire 2019/20 season, but carryover will be deliverable early in the season and will be extended as resource improvements occur.

“Based on assumed use to the end of 2018/19, allocation carried over into 2019/20 and climate-adjusted flow records, the risk of spill in the Goulburn system during 2019/20 is currently estimated to be less than 10 per cent. The risk in the Murray system is about 35 per cent. The Campaspe system currently has a 40 per cent risk.

“Customers may wish to factor this into their plans for the remaining months of 2018/19.”

Further detail on outlook for the 2019/20 season

The outlooks for 2019/20 seasonal determinations are based on historical flow records that have been adjusted to match climate conditions observed since 1975. The outlook scenarios presented are:

Wet: Inflow volumes to major storages that are greater in 10 years out of 100

Average: Inflow volumes to major storages that are greater in 50 years out of 100

Dry: Inflow volumes to major storages that are greater in 90 years out of 100

Extreme Dry: Inflow volumes to major storages that are greater in 99 years out of 100

The following tables summarise the estimated high-reliability water share seasonal determinations through the season for each scenario in the Murray, Goulburn, Loddon, Campaspe, Broken and Bullarook systems.

Murray System Outlook for Seasonal Determination of High-Reliability Water Shares

Inflow Conditions 1 July 2019 15 August 2019 15 October 2019 17 February 2020
Wet  40% 74% 100% 100%
Average  20%  42% 79% 100%
Dry  0%  23% 41% 58%
Extreme Dry  0%  8% 9% 20%

 

Goulburn System Outlook for Seasonal Determination of High-Reliability Water Shares

Inflow Conditions 1 July 2019 15 August 2019 15 October 2019 17 February 2020
Wet 43% 87% 100% 100%
Average  18% 44% 84% 100%
Dry  6%  21% 39% 47%
Extreme Dry  2% 7% 14% 18%

 

Campaspe System Outlook for Seasonal Determination of High-Reliability Water Shares

Inflow Conditions 1 July 2019 15 August 2019 15 October 2019 17 February 2020
Wet 100% 100%  100% 100%
Average  23%  70% 100% 100%
Dry  16%  21% 31% 32%
Extreme Dry  16%  16% 16% 16%

 

Loddon System Outlook for Seasonal Determination of High-Reliability Water Shares

Inflow Conditions 1 July 2019 15 August 2019 15 October 2019 17 February 2020
Wet  43%  87% 100% 100%
Average  12%  44% 84% 100%
Dry  0%  3% 31% 37%
Extreme Dry  0%  0% 0% 0%

 

Broken System Outlook for Seasonal Determination of High-Reliability Water Shares

Inflow Conditions 1 July 2019 15 August 2019 15 October 2019 17 February 2020
Wet 33% 76% 100% 100%
Average  0%  6% 100% 100%
Dry  0%  0% 0% 7%
Extreme Dry  0%  0% 0% 0%

 

Bullarook System Outlook for Seasonal Determination of High-Reliability Water Shares

Inflow Conditions 1 July 2019 15 August 2019 15 October 2019 17 February 2020
Wet  12% 100% 100% 100%
Average  0%  100% 100% 100%
Dry  0%  0% 7% 39%
Extreme Dry  0%  0% 0% 0%

 

Additional outlook scenarios for each system are available from the Northern Victorian Resource Manager website ( www.nvrm.net.au/outlooks ).

Outlooks for low-reliability water shares (LRWS) will be prepared during the 2019/20 season if seasonal determination are 100% HRWS and there is the possibility of LRWS being allocated.

Upcoming Resource Manager Announcements

  • The next 2018/19 seasonal determination announcement will be released on Friday March 1, 2019.
  • The 2019/20 seasonal determination outlooks will be updated on Wednesday May 15, 2019.
  • The first 2019/20 seasonal determination announcement will be released on Monday July 1, 2019 and will include an assessment of the probability of spill in the Murray, Goulburn and Campaspe systems and an updated outlook.