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The forest’s Victorian components are the Barmah National Park and part of the River Murray Reserve, covering 28,500 ha of forest and wetlands that support a vast range of significant plant and animal species and culturally significant sites to the Yorta Yorta.

The wetlands throughout the forest continue to provide a constant source of nutritional foods and significant fibres for the Yorta Yorta People. It is also evident that the resources in the landscape were utilised to manufacture canoes, shields and carrying devices.

Flooding in the Barmah-Millewa Forest depends on flows in the Murray River. A natural narrowing of the river (commonly referred to as ‘the Barmah Choke’) restricts flow and causes overbank flooding when flows below Yarrawonga Weir exceed the channel’s capacity. This restriction influences both the operation of Yarrawonga Weir and the upper limit of environmental flows that can be delivered to the forests. The Yorta Yorta People see this narrow part of their Dhungulla as a culturally significant creation story, and it provides ecosystem services both from a culturally and environmentally signifcant viewpoint. The name ‘the Barmah Choke’ is not a culturally appropriate name for the Yorta Yorta and is seen as a negative way to view their traditional lands and waters. Yorta Yorta People may refer to this as the ‘Pama Narrows’.

Before the river was regulated, Barmah-Millewa Forest would have regularly flooded with high flows from rainfall in winter and spring. These regular floods shaped a rich, productive forest environment. The construction and operation of Hume Reservoir and Dartmouth Dam have greatly reduced the size and frequency of natural winter/spring floods in Barmah-Millewa Forest.

Also, operational deliveries to supply water to users downstream of the Barmah Choke can cause unseasonal low-level floods, which can damage the forest and banks of the river depending on the timing and volume of the flows. Country for the Yorta Yorta People continues to change, but the changes have been rapid post-settlement due to infrastructure installation and river regulation. This has changed Country culturally and environmentally for the Yorta Yorta People. Their language word for water is Wala and this includes if an area is wet but may imply to others a ‘flood’ which is viewed as negative water.

The delivery of irrigation water during summer/autumn is managed to minimise unseasonal flooding of the forest. Regulators along the banks of the Murray River that control flow between the river and the forest remain closed during summer and autumn to restrict flow through low-lying flood runners. The delivery of water to Barmah-Millewa Forest is also limited by a flow constraint below Yarrawonga Weir to minimise impacts to adjacent farming operations in NSW. The current constraint limits regulated flows to a maximum river level of 3.3 m at the Tocumwal gauge (about 18,000 ML per day downstream of Yarrawonga Weir), subject to various conditions. Regulated flow up to a river level of 3.0 m on the Tocumwal gauge (about 15,000 ML per day downstream of Yarrawonga Weir) can be delivered at any time during the year and is not subject to conditions. To overcome this constraint, most environmental flows are shared between Barmah and Millewa forests to deliver water to low-lying wetlands in each forest at least every second year. It is currently not possible to achieve the desired flood depth and duration for floodplain marsh vegetation in both forests at the same time without larger natural flooding.

Water management at Barmah-Millewa Forest seeks to build on natural flow and the delivery of consumptive and operational water en route to optimise environmental outcomes when possible. As Barmah-Millewa Forest is located towards the upper reaches of the regulated portion of the Murray River, water for the environment that passes through the forest and returns to the river can often be used at sites further downstream as part of multi-site watering events.

Traditional Owners

System map

Environmental watering objectives in Barmah Forest

Connected icon
Enable carbon and nutrient cycling between the floodplain and river through connectivity
Maintain or increase habitat for native fish and increase their population
Maintain or increase habitat available for frogs
Maintain or increase habitat available for turtles including the broad-shelled turtle
Plant icon
Enhance the health of river red gum communities and aquatic vegetation in the wetlands and watercourses and on the floodplain

Promote the growth of floodplain marsh vegetation communities, with a particular focus on increasing the extent of Moira grass
Provide feeding and nesting habitat for the successful recruitment of colonial nesting waterbirds
Provide early-season flushing of the lower floodplain to reduce the risk of low-oxygen events in summer

Environmental values

The Barmah-Millewa Forest is the largest river red gum forest in Australia and the most intact freshwater floodplain system along the Murray River. The forest supports important floodplain vegetation communities including the threatened Moira grass plains and is a significant feeding and breeding site for waterbirds including bitterns, ibis, egrets, spoonbills and night herons. Significant populations of native fish, frogs and turtles also live in the forest’s waterways. Barmah Forest is known to support 74 plant and animal species protected under state and national legislation.

Recent conditions

Despite a La Niña event in south-eastern Australia, Barmah Forest experienced drier-than-average conditions throughout most of 2020-21. Maximum temperatures were generally close to the monthly long-term average, and there were no prolonged hot spells in summer. Local rainfall was below the long-term mean (measured at Echuca) in winter, spring and summer. Carryover of water combined with Murray allocations in Victoria (100 percent of high-reliability water shares) and New South Wales (50 percent of general security) provided sufficient water for the environment to meet the planned watering actions in Barmah Forest.

Forest regulators were opened from August 2020 to December 2020 to allow a natural connection between the Murray River and the waterways within Barmah Forest. Two small natural floods occurred in Barmah Forest in July and August 2020. Water for the environment was delivered to the forest from October to mid-December, to mimic some of the low-level flooding that would have naturally occurred without river regulation. The environmental watering event was part of a coordinated ‘southern spring flow’ that aimed to achieve environmental objectives along the Murray River from Hume Reservoir to the sea. Managed environmental flows slowly reduced through December to enable fish and turtles to return to the main channel, but a short pulse was delivered during the flow recession to trigger golden and silver perch spawning. One regulator remained open in Barmah Forest from mid-December to February to maintain water levels in a wetland until breeding white ibis, straw-necked ibis and royal spoonbills successfully fledged their chicks.

All watering actions for Barmah Forest aligned with an average scenario were delivered as planned in 2020-21, noting the delivery of autumn/winter low flows in May and June 2021 had not occurred at the time of writing. Maintaining a winter/spring connection between the river and the forest enabled carbon and nutrient exchange and improved food resources and habitat for fish, frogs, turtles and waterbirds. Low-level flooding in spring supported wetland plant growth and flowering for species (such as Moira grass) that were unable to flower in 2019-20 due to floodplain watering ending mid-October 2019. The targeted wetland watering through summer helped some 450 pairs of ibis and spoonbills successfully fledge young birds. This was the first successful nesting for these species in Barmah Forest since 2016-17. Bitterns were also recorded calling throughout the forest wetlands in 2020-21, and they are likely to have bred. The drying phase implemented throughout the forest in summer/autumn 2020-21 is important to maintain plant diversity and wetland productivity.

The spring environmental flow to the forest was diverted a little more into Barmah Forest than Millewa Forest in 2020, to achieve the best possible outcomes for the floodplain marshes in Barmah Forest while somewhat compromising the equivalent outcomes in Millewa Forest. This reflected a delivery targeting 3.0 m in the Murray River at Tocumwal (about 15,000 ML per day downstream of Yarrawonga). Delivering to the current maximum constraint of 3.3 m at Tocumwal in 2021-22 would improve floodplain marsh vegetation outcomes in both Barmah and Millewa forests, as well as increase lateral connection and provide more habitat for native fish, turtles, frogs and waterbirds.

Traditional Owner cultural values and uses

‘We are the First People of this place. We were here even before the Murray River flowed through Barmah.’— Uncle Des Morgan, Yorta Yorta Elder
Joint Management Plan for Barmah National Park

Yorta Yorta are joint managers of Barmah National Park under a Traditional Owner Land Management Agreement with the State of Victoria. Goulburn Broken CMA worked with the Yorta Yorta Nation Aboriginal Corporation during the water for the environment planning process to get their feedback about planned watering actions. Yorta Yorta Traditional Owners have been involved in the development of longer-term management plans that have informed these watering actions.

Examples of Yorta Yorta cultural values and uses in Barmah Forest that are supported through environmental flow delivery include:

  • maintaining refuges, which protects turtles that are an important totemic species for the Yorta Yorta People
  • watering to support floodplain marsh vegetation, which includes important food, fibre and medicinal plants (such as sneezeweed and weaving sedge)
  • healthier river red gums, which has benefits for important Yorta Yorta sites and significant markings such as a scarred tree and furthers connections to Country
  • broader restoration to achieving health of Country.

Social, recreational and economic values and uses

In planning the potential watering actions in Table 1, Goulburn Broken CMA considered how environmental flows could support values and uses including:

  • water-based recreation (such as boating and fishing)
  • riverside recreation and amenity (such as birdwatching, camping, benefits physical, mental and social wellbeing of  residents and visitors)
  • community events and tourism (such as boat tours)
  • socio-economic benefits (such as apiarists and irrigation diverters)

Scope of environmental watering

Table 1 Potential environmental watering actions, expected watering effects and associated environmental objectives for the Barmah Forest

Potential environmental watering action

Expected watering effects

Environmental objective

Winter/spring forest low flow to various waterways in Barmah Forest (variable flow rates and duration during July to November)

  • Provide a gradual connection of waterways with the Murray River to minimise erosion within those waterways
  • Provide flow in forest waterways to ensure adequate refuge pools persist for native fish and turtles
  • Provide adequate depth and connection between floodplain waterways and the river to facilitate the movement of native fish
  • Remove accumulated organic matter from waterways to cycle carbon to the river system and minimise the risk of hypoxic blackwater by ensuring through-flow commence in the cooler months

Fish iconMountain iconsTurtle iconJigsaw iconWater drop icon

Winter/spring/summer low flow (8,500-18,0001 ML/ day below Yarrawonga Weir during August to December)

  • Maintain a sufficient water level in the Murray River main channel to avoid Murray cod nest abandonment, increase juvenile survival and improve dispersal opportunities

Fish icon

Spring/summer fresh(es) in the Murray River channel (one to three freshes that increase flow by at least 500 ML/day and maintain it for two to eight days during October to December)

  • Provide variable water levels once water temperatures exceed 22o C, to trigger spawning of native fish species, primarily silver perch

Fish icon

Spring/summer/autumn freshes to Gulf and Boals creeks (100 ML/day for three to five days as required during November to April)

  • Maintain critical refuge pools to provide habitat for native fish and turtles
  • Flush refuge pools to maintain water quality

Fish iconTurtle icon Water drop icon

Spring/summer/autumn low flow to floodplain waterways including Sandspit, Gulf, Big Woodcutter, Boals and Island creeks and Punt Paddock Lagoon (200 ML/day for 30 to 60 days during November to April)

  • Replenish refuge pools in permanent waterways to maintain water quality, fish and turtle populations
  • Maintain connectivity between the forest and the river
  • Remove accumulated organic matter, cycle carbon to the river system and minimise the risk of hypoxic blackwater

Fish iconTurtle iconWater drop iconJigsaw icon

Fill or top-up Boals Deadwood, Harbours Lake, Reedy Lagoon and Top Island wetlands (200-400 ML/day for four and a half months during September to February)

  • Provide a cue to initiate waterbird breeding and maintain a depth of at least 0.5 m beneath reed bed nesting breeding colonies
  • Maintain wetting duration and depth for growth of wetland vegetation

Plant iconHeron icon

Spring wetting of floodplain marshes (variable flow rates of > 9,500-18,0001 ML/day below Yarrawonga Weir for three months during September to December)

  • Wet open plains for sufficient depth and duration to allow the growth of floodplain marsh vegetation
  • Inundate forest wetlands and low-lying floodplain areas to create foraging opportunities for waterbirds and increase available habitat for turtles, frogs and small-bodied native fish

Fish iconFrog iconTurtle iconPlant iconHeron icon

Autumn/winter low flow in the Murray River (1,800- 4,000 ML/day downstream of Yarrawonga during May to June)
  • Increase water depth in the Murray River channel to provide habitat for large-bodied native fish in the Murray River and unregulated anabranches in Barmah-Millewa Forest

Fish icon

1 The maximum flow constraint is a level of 3.3 m at the Tocumwal gauge in the Murray River, estimated at 18,000 ML/day downstream of Yarrawonga Weir. The maximum flow rate actually delivered may vary for these actions.

Engagement

Table 2 shows the partners organisations with which Goulburn Broken CMA engaged when preparing the Barmah Forest seasonal watering proposal.

Seasonal watering proposals are informed by longer-term regional catchment strategies, regional waterway strategies, environmental flow studies, water management plans and other studies. These incorporate a range of environmental, cultural, social and economic perspectives and longerterm integrated catchment and waterway management
objectives. For further details, refer to the Goulburn Broken Regional Catchment Strategy and the Goulburn Broken Waterway Strategy.

Table 2 Partners engaged in developing the Barmah Forest seasonal watering proposal

Partner and stakeholder engagement
  • Goulburn Murray Landcare Network
  • Turtles Australia
  • Commonwealth Environmental Water Office
  • Trellys Fishing and Hunting
  • Field and Game
  • Yorta Yorta Nations Aboriginal Corporation
  • Goulburn-Murray Water
  • Parks Victoria
  • Murray Darling Basin Authority (the Living Murray program)

Page last updated: 13/08/21