Projects

The Barmah-Millewa Forest is the largest river red gum forest in Australia. As a listed Ramsar Wetlands, it's a significant waterbird breeding site. This project involves changing the rules associated with the water set aside by Victoria and NSW in an environmental account.

Victoria and NSW established BMFEWA in the late 1990s. Since then, many newly created environmental water entitlements.

The operational rule change will improve the coordination of the BMFEWA with the environmental water recovered under the Basin Plan. This will improve coordination and lead to better environmental outcomes.

It will enable more effective use of BMFEWA and improve the number of successful deliverable environmental events with the same volume of allocated water.

Download the business case for operating rule change to the use of the Barmah-Millewa Forest Environmental Water Allocation. (PDF, 10.8 MB)

Hume Dam is the major operating storage on the Murray River system. The Hume Dam releases irrigation, domestic and stock, urban and environmental water to Victoria and New South Wales, and provides about one-third of South Australia's entitlement.

Hume Dam also affects the delivery of water to many important environmental assets. Prior to this operating rule change, Hume Dam’s operators were not permitted to allow the flow rate below the dam to fall more than 150 mm a day (six inches – ‘the six-inch rule’) at Doctors Point. This rule was made to minimise risk of river-bank slumping.

The rule was reviewed by the Murray-Darling Basin Authority who found it was too conservative and could be relaxed without an unacceptable increase in slumping risk.

‘The six-inch rule’ uses more water than if the flow rate is allowed to drop more quickly. It also contributes to unseasonal flooding of Barmah-Millewa Forest — an adverse environmental impact — because dam releases cannot be quickly scaled back when rainfall means that irrigators no longer need water they have ordered.

This project will save water as well as reducing flooding risks to Barmah-Millewa Forest.

Download the business case for flexible rates of fall in river levels downstream of Hume dam – the six inch rule. (PDF, 6.3 MB)

Hume Dam provides Victoria, New South Wales and about one-third of South Australia's (SA) entitlement for irrigation, urban, domestic and stock use.

Hume Dam also affects the delivery of water to many important environmental assets.

Before the change, Hume Dam’s operators couldn't allow the flow rate below the dam to fall more than 150 mm a day. Or, approximately six inches from the measurement point at Doctors Point. This rule was introduced to reduce the risk of river-bank slumping.

The Murray-Darling Basin Authority reviewed this role and found it was too conservative. As a result, it could be relaxed without an unacceptable increase in slumping risk.

The six-inch rule uses more water than if the flow rate is allowed to drop more quickly. It also contributes to unseasonal flooding of Barmah-Millewa Forest — an adverse environmental impact. This is because dam releases cannot be quickly scaled back when rainfall means that irrigators no longer need water they have ordered.

This project will save water as well as reduce flooding risks to Barmah-Millewa Forest.

Download the business case: Business case for flexible rates of fall in river levels downstream of Hume dam – the six inch rule. (PDF, 6.3 MB)

Airspace management involves calculating the amount of total space available for water storage. This figure is an important management tool for 2 reasons:

1. It protects the storage and reliability of water supplies.
2. It's management also mitigates downstream flood risks to local communities.

These target volume calculations take into account the Hume's total capacity, as well as forecast inflows and irrigator demands. Before the proposed rule change, environmental demands were not considered.

This operating rule change considers environmental water demands in calculating the airspace.

Some of the rule change benefits are:

• A reduced need for the dam operators to pre-release water in spring to create more airspace in the storage in advance of potential inflows.
• More water being available in Lake Hume.

Download the business case for operating rule change to Hume Dam airspace management and pre-releases. (PDF, 10.3 MB)

A key problem for operators is figuring out how much water to release from storage each day. It calls for close consideration, so they can meet all the Basin Plan's commitments.

Operators don't have a perfect knowledge of river conditions and make conservative assumptions. To be safe, they release extra water and the excess is an operational loss.

Before and after the Millennium Drought, there was a lot of water reform and shifts in practices. Operators are now making informed decisions with more accurate and plentiful data.

With lower operational losses, operators can better allocate water based on the demands. It's an enduring improvement in efficiency and the project sought permanent recognition.

Now, this project is included in the package of notified supply measures. Despite this, these offsets were not included in the 605 GL offset determination in 2017.

The project has been retained in the package as a notified project to enable governments to consider the project again in the future.

Download the business case for improved regulation of the River Murray. (PDF, 8.7 MB)

This project involved changes to rules about flows from the Snowy Hydro scheme to the Murray River.

In 2002, Victoria, NSW and the Commonwealth agreed on funding for water efficiency and water entitlement purchases in the Murrumbidgee and Goulburn river systems.

The water recovered allows up to an extra 70 GL and 212 GL each year to be released to the Murray and Snowy rivers for environmental purposes.

Before the rule change, the release of that water was at the discretion of Snowy Hydro. Releases generally suited Snowy Hydro’s commercial outcomes, which limited the environmental benefits.

In 2011, the Snowy Hydro licence changed along with the release rules for this water. This change is known as River Murray Increased Flows (RMIF).

As a result, the Victorian and New South Wales governments now hold that water and order its release for environmental outcomes in the Murray River downstream of Lake Hume.

This project provides a means to control the timing of RMIF water releases from the Snowy Scheme, allowing more flexibility to achieve environmental outcomes targeted in the Murray River below Hume Dam.

Download the River Murray Increased Flow (RMIF) - Current notification (Amendment 1).

This project aims to maximise the benefits of water for the environment across the southern-connected Basin by accelerating improvements in system-wide coordination and the development of new forecasting and planning tools and processes.

This is an opportunity to address long-standing issues relating to coordination and delivery of water for the environment to keep our floodplains and wetlands healthy and provide environmental benefits for the whole system.

The project will respect the independent decision-making of environmental water holders, catchment management authorities and water corporations.

The project will be delivered in stages. The first stage (1A) is now underway and is largely investigative, focusing on reviewing the current knowledge base to inform detailed planning and requirements for the following stages.

The project will take several years to develop, test and review the new tools and processes before being put into action.

This project is sometimes called Hydro-cues, as the initial concept focused on releasing water from storages in response to hydrological cues.

Download the business case Enhanced Environmental Water Delivery (EEWD) - Current notification (Amendment 2).