The trial will connect environmental flows between the northern and southern Murray-Darling Basin. This aims to maximise Basin-wide environmental outcomes, while ensuring that existing water users and Victoria’s Murray water resources are protected.
The north-south environmental water trial
Victoria supports the protection of environmental water through the connected Murray system to improve outcomes across the Basin, including in the Victorian lower Murray floodplain.
Under the Murray-Darling Basin Agreement all inflows to the Menindee Lakes are shared between Victoria and New South Wales to support Murray and lower Darling water resources, including the allocation of water to all entitlement holders.
The Australian government has purchased water for the environment in the northern Murray-Darling Basin as part of the Basin Plan. The Murray-Darling Basin Authority has undertaken analysis and provided assurance that this water is being protected as it flows through the northern Basin and can be managed through the Menindee Lakes without adversely impacting Victorian water availability.
Based on this assurance, Victoria has agreed to a three-year trial (July 2025 to June 2028) to protect the environmental water recovered in the northern Basin that arrives at the Lakes, and shepherd that water through to the southern Basin. These arrangements have been agreed on a trial basis while operational, accounting and delivery arrangements are monitored and tested to make sure there are no material impacts on Victorian entitlement holders.
Protecting environmental water through the northern Basin to the Menindee Lakes
Since November 2020, New South Wales have had procedures in place to protect water that has been recovered for the environment in the northern Basin to flow downstream to the Menindee Lakes.
The trial refers to this environmental water arriving at the Lakes as ‘Active Environmental Water’ (AEW). This is because NSW must ‘actively’ manage the water in the upstream Barwon-Darling River to shepherd it through to the Menindee Lakes. NSW does this through tracking daily inflows and changing licenced pumping thresholds as the water flows down the river.
The amount of AEW will vary from year to year. The MDBA undertook modelling as part of the Northern Basin Review in 2016. From this modelling, the MDBA estimates that the long-term average volume of AEW reaching the Menindee Lakes is about 150 GL/year. Victoria’s share is equal to half this estimated amount (75 GL/year).
Estimates of the long-term average of AEW reaching the Menindee Lakes will continue to improve as knowledge of environmental water delivery improves and implementation of the Basin Plan continues.
This additional environmental water flowing to the Menindee Lakes and through to the Murray River will enable a range of additional environmental outcomes in NSW, Victoria and South Australia.
The Victorian Menindee Lakes Trial Entitlement
The Minister for Water has approved an amendment to the Victorian Murray Flora and Fauna Bulk Entitlement to protect Victoria’s share of AEW arriving at the Lakes and support implementation of the trial.
The amendments bring this water under Victoria’s entitlement framework through the introduction of a new ‘Menindee Lakes Trial Entitlement’. The Victorian Environmental Water Holder (VEWH) will manage the entitlement consistent with its functions under the Water Act 1989 and consistent with the agreed conditions of the trial.
The bulk entitlement also provides for VEWH to continue to access this water if enduring arrangements are agreed in the future. No water is available to the VEWH under the entitlement if, for any reason, the trial ceases.
Consistent with the agreed trial arrangements, the bulk entitlement also includes various risk mitigation measures that ensure water availability for Victorian entitlement holders will not be adversely impacted – this includes the setting aside of a reserve, arrangements for the management of physical spills, and the requirement to develop operating arrangements consistent with the conditions of the trial.
More information can be found on the bulk entitlements page. The amendment order and consolidated bulk entitlement instrument can be found on the Victorian Water Register website.
The Menindee Lakes
The Menindee Lakes, located on the Lower Darling (Baaka) River in far western New South Wales (NSW), are a series of interconnected lakes that form a natural connection point between the Barwon-Darling River in the northern Murray-Darling Basin and the Murray River in the southern Murray-Darling Basin.
The Lakes play a crucial role in supporting the southern Murray-Darling Basin, providing water resources, supporting river operations and the environment. They underpin the reliability of Victorian Murray entitlements, support water supply resilience during dry periods in the Murray River and provide an additional way to deliver water to meet demands in the lower Murray that help to manage shortfall risks.
The Lakes also offer significant ecological benefits, providing flows and habitat for native flora and fauna, and supporting values for First Nations and local communities.
Management of water under the Menindee Lakes Trial Entitlement
Delivery of water under the Menindee Lakes Trial Entitlement will occur in line with the VEWH’s annual Seasonal Watering Plan. The VEWH works in close partnership with environmental water managers in NSW, South Australia, the Commonwealth Environmental Water Holder and the Living Murray program through the Southern Connected Basin Environmental Watering Committee to coordinate flows across the southern Murray Darling Basin.
The VEWH will manage the water under these established planning and delivery partnerships to achieve environmental outcomes as efficiently as possible. The VEWH will also work directly with the holder of NSW’s share of AEW inflows to jointly manage the water.
Environment benefits of the North-South Trial
The amended Flora and Fauna bulk entitlement protects Victoria’s share of AEW by increasing available environmental water, enhancing environmental outcomes and delivering on the objectives of the Murray-Darling Basin Plan.
In-channel habitat for native fish and other water dependent animals will benefit from the additional flow into the southern Basin. Fringing, in-stream and floodplain vegetation will benefit both immediately downstream of the Lakes and throughout the lower Murray and its floodplains, including in Victoria’s Lindsay, Mulcra and Wallpolla islands waterways.
The additional water will also provide greater flexibility in using environmental holdings across the connected Murray system, achieving better outcomes. For example, improved landscape-scale outcomes can be achieved by coordinating releases from the upper Murray storages to coincide with releases from the Lakes, providing sufficiently sized river pulses to trigger fish spawning events across the connected Murray System.
Environmental water protected under the trial will also support local environmental outcomes, by providing additional flows into the lower Darling-Baaka River that can help to improve water quality and provide favourable conditions for the recruitment of Basin-wide native fish populations.
Page last updated: 16/04/26