Murray and Lower Darling Environmental Water Advisory Group communique

Murray Environmental Water Advisory Group Meeting

The Murray Environmental Water Advisory Group met online on 28 November 2024.

Edward-Wakool update

The Murray River multi-site event (directed releases from Hume Dam) maintained elevated flows in the Edward–Wakool-Niemur system over spring for Murray cod nesting. Elevated baseflows will be delivered in the Yallakool–Wakool over summer and autumn.

In October 2024, increased environmental flows were trialled in the Edward River, downstream of Stevens Weir and Colligen Creek. The flows entered the Werai Lands Ramsar site via the Tumudgery Creek and Reed Bed Creek and returned to the Colligen Creek, Edward River, and Niemur River. Flows also entered Mary Kelly Creek and Cooyeo Creek but did not completely connect with the receiving streams.

Lower Darling River update

The spring flow delivered for Murray cod breeding was superseded by River Murray Operations, which delivered higher operational flows to meet downstream demand in the Murray River.

If wet conditions and high flows in the Murray River continue, the demand for operational flows from Menindee Lakes Storage will decrease. Environmental water may then be released from Menindee Lakes Storage to meet the environmental water requirements in the Lower Darling.

Reduction to 480 gigalitres of Menindee Lakes Storage volume is occurring at a similar time to previous years (as at the time of meeting).

A report on native fish monitoring conducted in the Lower Darling and Menindee Lakes from 2022–24 has been released: Monitoring native fish response to flows in the Lower Darling River 2022–24.

Great Darling Anabranch and Lower Murray update

A 2022–23 fish monitoring project, managed by the NSW Department of Climate Change, Energy, the Environment and Water and co-funded by the Commonwealth Environmental Water Holder, estimated one million golden perch in Lake Cawndilla. Additionally, 65,000 golden perch moved to Tandou Creek, and 1,000 migrated to the Murray River. Read the report outlining these findings: Native fish movement in the Great Darling Anabranch 2022–23.

Small-bodied native fish – reintroduction program

The NSW Department of Climate Change, Energy, the Environment and Water is working with the Department of Primary Industries and Regional Development – Fisheries to support reintroducing small-bodied native fish into wetland areas. Purple-spotted gudgeon (a threatened native small-bodied fish species) will be released into Bingera Creek, near Tooleybuc, in December 2024 as part of this program. Subsequent monitoring will be conducted to determine the population's health.

Woodleigh wetland is another potential candidate for the program. To date, the environmental water delivered to the wetland has attracted a diversity of waterbirds, and native vegetation (including Moira grass) has responded positively.

Southern bell frogs and waterbirds

The North Dale Billabong (located along the Edward River) is one of several sites in the Saving our Species southern bell frog program. The billabong is currently undergoing a drying phase to eliminate exotic carp that have proliferated in the wetland since the 2022-23 floods. With the carp removed, the southern bell frog and other frog species are expected to benefit. The plan is to re-fill North Dale Billabong in autumn 2025.

There was a great waterbird response at Errinundra wetland, a Lignum-dominated black box wetland in the Murrabit–Swanhill region. This wetland also supports a population of southern bell frog.

Delivery of environmental water to Lake Victoria and Nampoo Station wetlands, located west of Lake Victoria, was delayed due to metering issues with portable pumps. These 2 wetlands are also part of the Saving our Species southern bell frog program.

Lake Gol Gol (located in Gol Gol, NSW) has the highest diversity of waterbirds in New South Wales. A new flume gate and flow meter were installed on the lake's regulator, funded by Commonwealth Environmental Water Holder and project-managed by the department. The department's team will work collaboratively with the Gol Gol Community Reference Group and Gol Gol Creek Water Users to deliver environmental water to the lake, with filling proposed for autumn 2025.

Millewa The Living Murray Icon Site update

The Living Murray program focuses on the delivery of water for the environment and monitoring of environmental outcomes, and it supports an Indigenous Partnership Program.

In 2024, drier forest conditions and delayed watering negatively affected the waterbird response in the forest, including Australasian bitterns, which were recorded calling in small numbers.

Conversely, superb parrot numbers were detected higher than in previous years, which is good news. Woodland birds, like the superb parrot, are a good indicator of forest conditions.

Predators are a significant threat at the site, and the Living Murray program has requested targeted baiting by the NSW National Parks and Wildlife Service.

The Living Murray program and Aboriginal community have been working together to translocate southern pygmy perch, a threatened small-bodied native fish, at Nine Panel Lagoon. This work is part of the Millewa Fish Recovery Strategy.

Recently, fish were tagged as part of the large-bodied native fish movement study. The fish exit (regulator closing) strategy was delayed due to higher Murray River flows.

Koondrook–Perricoota–Campbells Island Icon Site update

The Koondrook–Perricoota and Campbells Island forests have received moderate and major floods over the past 2 winter-springs.

Monitoring detected large numbers of native fish and crustaceans in the forests' wetlands, however, carp dominated overall biomass.

Environmental watering in spring 2024 did not proceed in Koondrook–Perricoota due to delays with Shear Paddock works and a lack of support from affected landholders. Watering may not be possible for at least 12 months until the Barber Creek and inlet regulator works are finished.

To maintain forest/floodplain condition and build ecological resilience, consecutive winter-spring watering is essential. Unfortunately, dry spring conditions in 2024 resulted in no overbank events, higher evapotranspiration rates, and 110 millimetres below the annual mean for regional rainfall. Residual pools in the forests are therefore expected to completely dry over summer.

Mid-Murray Flow MER 2.0 update

Mid-Murray Flow MER 2.0 is a science program funded by Commonwealth Environmental Water Holder. The Flow MER 2.0 program covers the Lower Murray and Lower Darling. The study area ranges from the Hume Dam to Mildura and includes the Edward–Wakool–Niemur system.

Charles Sturt University has started monitoring the Edward River flow trial in spring 2024. They are working with Traditional Owners to report on ecological outcomes in Werai Lands. They held productive workshops to discuss results, share different perspectives, explore how to present the results, and inform the management of Werai Lands and future watering actions.

Flow MER 2.0 incorporates a range of citizen science programs. These include river flow gauging with the Western Murray Land Improvement Group, Barkindji–Maraura Elders Environmental Team, and Murray Darling Wetlands Working Group. These programs also conducted Lignum surveys at Gol Gol wetlands and Bottle Bend using drones and ground-truthing techniques.