VEWH - Central Murray wetlands

The Central Murray wetlands are almost wholly contained within the Torrumbarry Irrigation Area and are all wetlands of regional or international significance. The area has experienced dramatic changes since European settlement with the construction of levees, roads and channels. Most of the wetlands are now cut off from natural flow paths and are rarely filled by natural floods. They rely on water for the environment to maintain their ecological character and health.

Ten of the central Murray wetlands can receive water for the environment from permanent infrastructure: Lake Cullen, Hird Swamp, Johnson Swamp, Round Lake, McDonalds Swamp, Lake Elizabeth, Lake Murphy, Richardson’s Lagoon, Third Reedy Lake and the Wirra-Lo wetland complex. Temporary pumps may be used to deliver water for the environment from the Murray River to some semipermanent wetlands in the Guttrum and Benwell forests.

System map

Environmental watering objectives in the Central Murray wetlands

Maintain and improve populations of listed threatened species including critically endangered Murray hardyhead and southern purple spotted gudgeon Maintain or increase populations of common small-bodied native fish (such as carp gudgeon and flatheaded gudgeon)

Maintain and improve populations of endangered growling grass frog Maintain populations of common native frogs (such as barking marsh frog, Peron’s tree frog and spotted grass frog)

Maintain populations of native turtle species (such as Murray River turtle and the common long necked turtle)

Restore and maintain the health of streamside trees (such as river red gum and black box)  Restore and maintain mudflat vegetation communities (such as tall marsh, herblands, rushes and sedges)  Restore and maintain native aquatic vegetation species (such as tassel, milfoil and pondweed)  Reduce the extent and density of invasive plant species  Support a mosaic of wetland plant communities across the region

Provide resting, feeding and breeding habitat for a variety of waterbird feeding guilds including threatened species (such as Australasian bittern, little bittern and brolga)

Provide carbon and nutrients to Pyramid Creek to boost the riverine food web

Environmental values

The wetlands in the Central Murray system support numerous listed threatened species ranging from vulnerable to critically endangered including the Australasian bittern, Murray hardyhead, Australian painted snipe, growling grass frog and the southern purple spotted gudgeon, which was presumed extinct in Victoria until it was found at Third Reedy Lake in spring 2019. When the wetlands receive environmental water, they can attract prolific birdlife and provide feeding and breeding habitat for many threatened and endangered bird species (including the eastern great egret and white-bellied sea eagle) listed under legislation and international agreements. Lake Cullen, Hird Swamp and Johnson Swamp are internationally recognised under the Ramsar Convention, while the other wetlands in the Central Murray system have bioregional significance.

Traditional Owner cultural values and uses

The wetlands and surrounding land in the central Murray region are rich in cultural heritage, with sites and artefacts of cultural practices present throughout the landscape. The rivers and floodplains are valued as food and fibre sources and contain many sites of significance such as camp sites and meeting places. Environmental watering supports values such as native fish, waterbirds and turtles, and promotes the growth of culturally important plants that provide food, medicine and weaving materials. The presence of water itself can be a cultural value, as well as the quality of the water, as healthy water promotes a healthy Country.

Barapa Barapa, Wamba Wemba and Yorta Yorta Traditional Owners have contributed to environmental water planning for wetlands important to them in the central Murray region in 2020-21. Focus areas include:

Barapa Barapa and Wamba Wemba Traditional Owners have highlighted maintaining or improving the health of wetland vegetation as a key priority across the wetlands. Watering activities in Guttrum Forest will again be a particular focus for Barapa Barapa and Wamba Wemba Traditional Owners in 2020–21 (as described below)
North Central CMA and Barapa Barapa Traditional Owners have collaborated to deliver the DELWP funded Decision-Support Tool project, which is guiding vegetation works at McDonalds Swamp, and Lake Leaghur and Lake Yando (sites within the Boort wetlands). This has allowed them to align watering actions in these wetlands with the watering requirements of the revegetation and enabled monitoring to be completed by Barapa Barapa
North Central CMA and Yorta Yorta Nation Aboriginal Corporation have considered watering priorities for 2020–21, with a particular focus on Richardsons Lagoon. The Yorta Yorta Traditional Owners are supportive of the current drying phase in the lagoon, and its objectives of aerating sediment, reducing carp and providing a boost to productivity when water returns.

Waterway managers are seeking opportunities to increase the involvement of Traditional Owners in environmental water planning and management. Where Traditional Owners are more deeply involved in the planning and/or delivery of environmental flows for a particular site, their contribution is acknowledged in Table 1 with an icon.

Watering planned and/or delivered in partnership with Traditional Owners to support Aboriginal cultural values and uses

Barapa Barapa and Wamba Wemba input to watering actions for Guttrum Forest in 2020–21

The proposed delivery of water for the environment to Guttrum Forest during 2020–21 has been planned in conjunction with the Barapa Barapa and Wamba Wemba peoples, for whom the wetlands and surrounding forest are places of high cultural significance. The Traditional Owners have been an important part of Guttrum Forest planning and management from the outset and were directly involved in the delivery of environmental flows to Reed Bed Swamp in 2019–20.

Barapa Barapa and Wamba Wemba collaborate with waterway managers to ensure that during watering events their cultural heritage is protected and that the hydrological needs of important cultural values (such as food and medicinal plant species, scar trees and ring trees) are supported through the timing and duration of planned watering actions to the forest.

The Traditional Owners advised that filling Guttrum Forest in winter 2020 and a top-up in spring would be appropriate timing to support large old trees and bird breeding. Additional watering in autumn/winter 2021 was recommended to prime the wetland for fills in the 2021–22 water year, to increase the duration of wetting.

Social, recreational and economic values and uses

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

water-based recreation (such as kayaking, canoeing, fishing, swimming and water sports)
riverside recreation and amenity (such as walking, running, cycling, camping, birdwatching and duck hunting)
community events and tourism (such as visitation during the hunting and fishing seasons, Breakfast with the Birds events (North Central CMA), supporting Aboriginal cultural heritage and history-based tours)
socio-economic benefits (such as ecosystem services like groundwater recharge, flood mitigation, nutrient treatment and carbon storage).

Recent conditions

The central Murray area had below-average rainfall and above-average temperatures throughout most of 2019–20. Rainfall in spring 2019 was well below the long-term average and as a result, storage inflows for the year were also much lower than average. Water for the environment was delivered to seven central Murray wetlands in 2019–20 in line with planning under a dry scenario.

Round Lake and Lake Elizabeth received environmental water during 2019–20 to maintain salinity within the target range for endangered Murray hardyhead. Lake Cullen, which has held water since the natural floods in 2016, was topped up in spring 2019 to support the growth and recruitment of submerged and emergent aquatic plants and provide feeding and roosting habitat for waterbirds.

Wirra-Lo wetland complex received environmental water during the spring and summer 2019–20 that primarily targeted growling grass frogs and wetland vegetation communities. Wetting and drying regimes are being staggered across the eight wetlands within the Wirralo wetland complex based on their ecological condition and site-specific watering needs, including to support revegetation projects and the feeding and breeding habitat of various species (such as the growling grass frog and Australasian bittern).

Water for the environment was delivered to Reed Bed Swamp and Little Reed Bed Swamp in Guttrum Forest for the first time in spring 2019. The watering action aimed to reduce the recent encroachment of river red gum saplings across the bed of the wetland and provide feeding and breeding habitat for waterbirds and frogs. Many of the large old fringing river red gums showed improved tree canopy with new growth after the watering event. Johnson Swamp was filled in spring 2019 to provide food and breeding habitat for waterbirds, especially Australasian bittern. Subsequent monitoring detected Australasian bittern breeding calls as well as large numbers of smallbodied native fish, waterbugs, frogs and eastern long-neck turtles. A spring fresh in Pyramid Creek was partly diverted through Johnson Swamp to help export nutrients, carbon and waterbugs from the wetland into the creek to increase the productivity of riverine food webs.

After completing its drying cycle, McDonalds Swamp received a partial fill in autumn 2020. The watering aimed to promote the growth of planted and naturally recruited river red gums, support early plant germination and promote winter feeding conditions for waterbirds and frogs, and prime the wetland for a spring fill.

Water for the environment was delivered to Third Reedy Lake for the first time in 2019–20. Goulburn-Murray Water used to manage Third Reedy Lake as a water storage, but it is no longer needed for that purpose and the longterm plan for the site is to restore a more natural wetting and drying regime to support a range of environmental values. Ecological surveys conducted as part of the decommissioning work recorded several southern purple spotted gudgeon at the site. The species was thought to be extinct in Victoria, and water for the environment is currently being used to maintain the population at Third Reedy Lake while long-term management plans for the site and the species are being developed.

Scope of environmental watering

Table 1 Potential environmental watering actions and objectives for the central Murray wetlands

Potential environmental watering action	Functional watering objective	Environmental objective
Round Lake (top-up as required)	Maintain salinity within 25,000–60,000 EC (may go up to 80,000 EC) to support suitable habitat and breeding conditions for Murray hardyhead and growing conditions of submerged aquatic plants
Lake Elizabeth (top-up as required)	Maintain salinity within 25,000–60,000 EC (may go up to 80,000 EC) to support suitable habitat and breeding conditions for Murray hardyhead, and growing conditions of submerged aquatic plants Provide permanent water as habitat for waterbirds
Wirra-Lo wetland complex – Brolga Swamp (fill in spring and top up as required)	Promote growth and maintenance of submerged and emergent aquatic vegetation Provide feeding and breeding habitats for growling grass frog and other frog species Provide open water and foraging habitats for shallow wading waterbirds and mudflat specialists to feed and breed Provide refuge and recruitment sites for freshwater turtles
Wirra-Lo wetland complex – Red Gum Swamp (fill in spring and top up as required)	Promote the growth and maintenance of existing red gum trees Provide feeding and breeding habitats for growling grass frog and other frog species Provide recruitment sites for freshwater turtles Provide resting, feeding and breeding habitat to support waterbirds
Wirra-Lo wetland complex – Bunyip Swamp East and Bunyip Swamp West (top up in spring, and further top-up as required)	Support the growth of recently established reed beds to create nesting habitat for Australasian bittern
Third Reedy Lake – (top up as required)	Maintain water level above 74.0m AHD (Australian Height Datum) to support critical habitat and breeding for the southern purple spotted gudgeon
McDonalds Swamp (fill in late winter/spring, and top up as required)	Promote the growth of planted and naturally recruited river red gums, native semi-aquatic and aquatic plants, which provide high-quality habitat for waterbirds to feed and breed Maintain feeding conditions for waterbirds if significant waterbird breeding occurs
Hird Swamp (west) (fill in spring and top up as required)	Promote the growth and establishment of wetland plant communities to provide high quality habitat for waterbirds, reptiles and frogs to feed and breed Maintain food for nesting waterbirds if significant breeding occurs
Hird Swamp (west) (through-flow to Pyramid Creek in spring/summer)	Deliver carbon-rich water to Pyramid Creek to increase the productivity of riverine food webs
Guttrum Forest (partial fill in winter 2020, with top-ups in spring/summer if required to support waterbird breeding)	Wet existing adult river red gums to support growth and drown river red gum saplings to maintain open-water habitat Promote the growth and re-establishment of aquatic and tall marsh vegetation Maintain depth of wetland to support frogs and waterbird feeding and breeding
Richardsons Lagoon (fill in winter/spring, top up as required)	Promote the growth of aquatic macrophytes, reeds and rushes, which in turn would support aquatic biota Wet the higher floodplain environment to maintain eucalypt floodplain woodland and create habitats for waterbirds, reptiles and frogs and associated wetland animals to feed and breed Increase food resources (e.g. waterbugs and zooplankton) for waterbirds and other wetland animals
Guttrum Forest (partial fill in autumn/winter 2021)	Increase water depth and extent to trigger wetland plants to germinate in late winter and early spring Provide feeding and refuge habitat for waterbirds and frogs

Engagement

Table 2 shows the partners, stakeholder organisations and individuals with which North Central CMA engaged when preparing the central Murray wetlands 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 North Central Regional Catchment Strategy and the North Central Waterway Strategy.

Table 2 Partners and stakeholders engaged in developing the central Murray wetlands seasonal watering proposal

Partner and stakeholder engagement
Birdlife Australia Commonwealth Environmental Water Office Department of Environment, Land, Water and Planning Goulburn- Murray Water Parks Victoria Department of Environment, Land, Water and Planning (land manager) Gannawarra Shire Council Campaspe Shire Council Swan Hill Rural City Council Loddon Shire Council Individual landholders and community members Field and Game Australia Gateway to Gannawarra Visitor centre Arthur Rylah Institute (Department of Environment, Land, Water and Planning) Contracted ecologists Dja Dja Wurrung Clans Aboriginal Corporation Yorta Yorta Nation Aboriginal Corporation Barapa Barapa Traditional Owners Wemba Wemba Traditional Owners

Partner and stakeholder engagement

Birdlife Australia
Commonwealth Environmental Water Office
Department of Environment, Land, Water and Planning
Goulburn- Murray Water
Parks Victoria
Department of Environment, Land, Water and Planning (land manager)
Gannawarra Shire Council
Campaspe Shire Council
Swan Hill Rural City Council
Loddon Shire Council
Individual landholders and community members
Field and Game Australia
Gateway to Gannawarra Visitor centre
Arthur Rylah Institute (Department of Environment, Land, Water and Planning)
Contracted ecologists
Dja Dja Wurrung Clans Aboriginal Corporation
Yorta Yorta Nation Aboriginal Corporation
Barapa Barapa Traditional Owners
Wemba Wemba Traditional Owners

Page last updated: 24/07/20