VEWH - Goulburn River

There are several environmental water holders in the Goulburn system. The Commonwealth Environmental Water Holder (CEWH) holds the largest volume, and the use of Commonwealth Water Holdings is critical to achieving outcomes in the Goulburn River, as well as priority environmental sites further downstream. Water for the environment held on behalf of the Living Murray program may assist in meeting objectives in the Goulburn system en route to icon sites in the Murray system (see subsection 1.4.2). Water held by the VEWH in the Goulburn system is primarily used to meet environmental objectives in the Goulburn River and the Goulburn wetlands, but it can also be used to support ecological objectives at downstream sites along the Murray River and in South Australia.

The construction and operation of Lake Eildon and Goulburn Weir have significantly altered the natural flow regime of the Goulburn River. Water-harvesting during wet periods, and releases to meet irrigation and other consumptive demands during dry periods, means that flow below these structures is typically low in winter/spring and high in summer/autumn. This effectively reverses the natural seasonal flow pattern. Land use changes and the construction of small dams and drainage schemes have further modified the Goulburn River’s flow regime. Levees and other structures prevent water from inundating the floodplain and filling many of the natural wetlands and billabongs. Several tributaries, including the Acheron, Yea and Broken rivers below Lake Eildon, add some flow variation on top of the Goulburn River’s regulated flow regime. Large floods that cause the Goulburn River’s storages to fill and spill are also important for the overall flow regime and its associated environmental values.

The priority environmental flow reaches in the Goulburn River are downstream of Goulburn Weir (reaches 4 and 5), which are collectively referred to as the lower Goulburn River. The mid-Goulburn River extends from Lake Eildon to Goulburn Weir (reaches 1 to 3). From early spring to late autumn, large volumes of water are delivered from Lake Eildon to Goulburn Weir to supply the irrigation system. During that period, flow in the mid-Goulburn River is usually well above the recommended environmental flow targets. Deliveries of water for the environment have the most benefit in the mid-Goulburn River (especially in reach 1 immediately downstream of Lake Eildon) outside the irrigation season when the flow is much lower than natural.

Environmental flow targets can sometimes be met by the coordinated delivery of operational water being transferred from Lake Eildon to the Murray River. These inter-valley transfers (IVTs) occur during the irrigation season between spring and autumn and may meet environmental flow objectives without the need to release water for the environment. In recent years, IVTs in the Goulburn River have significantly exceeded the environmental flow recommendations for summer and early autumn and have damaged bank vegetation and eroded the riverbanks. A new interim Goulburn to Murray trade rule and operating plan was introduced in 2021-22. It is intended to prevent further damage to the lower Goulburn River from prolonged high flow over summer and autumn.

Proportion of water entitlements in the Goulburn River held by private users, water corporations and environmental water holders on 30 June 2020

System map

Environmental watering objectives in the Goulburn River

Protect and increase populations of native fish

Maintain populations of turtles

Increase populations of platypus

Maintain the form of the riverbank and channel and a high diversity of river bed surfaces to support all stream life

Maintain abundant and diverse waterbug communities to support riverine food webs

Minimise the risk of hypoxic blackwater

Provide sufficient rates of carbon and nutrient production and processing to support native fish and waterbug communities

Increase the abundance of aquatic and flood-tolerant plants in the river channel and on the lower banks to provide shelter and food for animals and stabilise the riverbank

Environmental values

The Goulburn River and its tributaries support a range of native fish (including golden perch, silver perch, Murray cod, trout cod, Macquarie perch, freshwater catfish), turtles, platypus and rakali (water rats). Aquatic vegetation, scour holes and woody debris within the channel provide high-quality habitat for adult and juvenile fish. River red gums are a dominant feature of the streamside zone along the length of the Goulburn River. These trees shade the river and provide habitat for many species, including the squirrel glider. Leaves that fall from the river red gums provide carbon that supports riverine food webs, and dead trees that fall into the river provide a surface for biofilms and waterbugs and habitat for fish. Birds (such as egrets, herons and cormorants) use trees along the river to roost and feed, while frogs benefit from shallowly wetted vegetation at the edge of the river channel and in adjacent wetlands.

The Goulburn River system is an important conservation area for threatened species. Several wetlands in the Goulburn catchment are formally recognised for their conservation significance. Tributaries of the mid-Goulburn River between Lake Eildon and Goulburn Weir host some of the last remaining Macquarie perch populations in the Murray-Darling Basin, while freshwater catfish occur in lagoons connected to reach 3 of the Goulburn River. Citizen science monitoring programs indicate the mid-Goulburn River supports a strong population of platypus, which are now classified as vulnerable under Victoria’s Fauna and Flora Guarantee Act 1988. Monitoring in recent years shows that environmental flows in the lower Goulburn River trigger golden perch and silver perch to spawn. However, the extent to which these spawning events contribute to populations locally and in the wider southern basin is unknown. Self-sustaining populations of Murray cod have been confirmed, and trout cod are extending their range in the lower Goulburn River.

Traditional Owner cultural values and uses

Goulburn Broken CMA consulted with the Taungurung Land and Waters Council and the Yorta Yorta Nation Aboriginal Corporation during seasonal water planning for the Goulburn River. The environmental and ecological objectives of the proposals were supported, and they align with the broad values of these Traditional Owner groups.

Increasing the involvement of Traditional Owners in the planning and management of environmental flows and ultimately providing opportunities to progress towards self-determination within the environmental watering program is a core commitment of the VEWH and its agency partners. This is reinforced by a range of legislative and policy commitments, including the Water Act 1989, the Victorian Aboriginal Affairs Framework, the 2016 Water for Victoria and in some cases, agreements under the Traditional Owner Settlement Act 2010.

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 5.4.1 with an icon. The use of this icon is not intended to indicate that these activities are meeting all the needs of Traditional Owners but is incorporated in the spirit of valuing their contribution and indicating progress towards deeper involvement.

Watering planned to support water angling activities

The Taungurung Land and Waters Council indicated there is alignment between planned environmental flows in the mid- Goulburn River (Waring) and Taungurung objectives and responsibilities to heal and care for Country. Reach 1 baseflows, and the winter and spring freshes will help protect the landscape and health of the river. These flows will help support cultural values, protecting intangible cultural heritage, valued species, traditional food and medicine plants. The flows will also support ongoing efforts by Taungurung and partner organisations to care for the river and its floodplain, including investigations into rehabilitating degraded significant sites.

The Yorta Yorta Nation Aboriginal Corporation indicated there is alignment between planned watering actions in the lower Goulburn River (Kaiela) (reaches 4 and 5) and the cultural and ecological values of the Yorta Yorta People. A Yorta Yorta representative contributed to the 2020 Kaiela (Lower Goulburn River) Environmental Flows Study, which shaped planning for environmental flows in the lower Goulburn River during 2021-22 and beyond. Through this consultation, Yorta Yorta and Goulburn Broken CMA have identified that environmental flows are critical for culturally important plant and animal species.

Flows encouraging spawning activity, recession flows to alleviate slumping of culturally important sites (such as middens and scar trees) and flows with a focus on reviving streamside vegetation are important to sustain food, fibre and medicine.

Social, recreational and economic values and uses

In planning the potential watering actions in Table 5.4.1, Goulburn Broken CMA considered how environmental flows could support values and uses such as:

water-based recreation (such as boating, canoeing, fishing, gaming, hunting and kayaking)
riverside recreation and amenity (for landholders and visitors)
community events and tourism (such as paddling and boating businesses)
socio-economic benefits (such as improving water quality for stock and domestic uses, irrigation diverters and water supply for settlements on the Goulburn River).

If the timing or management of planned environmental flows may be modified to align with a community benefit, this is acknowledged in Table 5.4.1 with the following icon.

Watering planned to support water angling activities

The Goulburn River provides numerous recreational and economic benefits. Environmental flows support native fish populations by providing fish passage and habitat and by encouraging fish migration and spawning, which in turn provides benefits for recreational anglers. Following community feedback, the timing of a targeted environmental flow in November/ December is planned to reduce impacts on river access around peak fishing periods, benefitting anglers and local businesses.

Recent conditions

Rainfall in the Goulburn catchment and inflows to Goulburn storages during 2021-22 were close to the long-term average. Natural flows contributed to winter and spring freshes, including a bankfull event of 19,500 ML per day at Shepparton in September. Allocations to high-reliability water shares reached 100 percent by October 2021, meaning sufficient water was available throughout the year to meet high-priority environmental flow requirements in the Goulburn River and support demands in the Broken, Campaspe and Loddon systems via trade.

Deliveries of water for the environment for the Goulburn system were managed in line with an average climate scenario throughout 2021-22. Most planned watering actions were fully or partially met with natural or environmental flows. A late-spring fresh was not delivered to allow newly germinated lower bank vegetation to establish. Natural flows delivered a winter fresh and spring fresh in the lower Goulburn River. Water for the environment was used to slow the recession after these natural events, to help optimise environmental outcomes. Water for the environment was also used to supplement lower-than-normal operational flow in reach 1 between March and November, to maintain habitat for fish and waterbugs and to deliver a spring and autumn fresh in the lower Goulburn River. The autumn fresh aimed to support bank vegetation and was timed to attract juvenile fish that recruited in the Murray River in the previous year. Ecologists used satellite tracking technology to monitor the movement of tagged golden perch and silver perch from the Murray River in response to freshes in the Goulburn River and other Murray tributaries. The results of that monitoring will inform future deliveries of water for the environment.

A new interim trade rule and operating plan for IVTs was introduced in 2021-22, which specifies the maximum monthly volumes of water that can be delivered from the Goulburn system to the Murray system. Wet conditions across the southern connected basin created low demand for IVTs from the Goulburn system, which meant the new trade rules were not tested. The low demand for IVTs also meant flow in spring and summer in the lower Goulburn River was within environmental flow recommendations for the first time since 2015-16. Ecological monitoring conducted during 2021-22 detected an improvement in vegetation condition on the banks of the lower Goulburn River compared to previous years and highlighted the importance of maintaining flows within environmental flow recommendations. Water for the environment will be used to build on bank vegetation recovery and support native fish migration in 2022-23.

Scope of environmental watering

Table 1 Potential environmental watering actions and objectives for the Goulburn River

Potential environmental watering action	Expected watering effects	Environmental objectives
Goulburn River reach 1
Year-round low flow (400-2,000 ML/day in reach 1)	Maintain habitat for small-bodied native fish Maintain adequate foraging habitat for platypus and reduce the risk of predation Provide habitat and food for turtles Wet and maintain riffles to provide habitat for biofilms and waterbugs Additional benefits to reach 1 of the Goulburn River when flows delivered are above 800 ML/day: scour fine sediment from the gravel bed and riffle substrate maintain existing beds of in-channel vegetation provide connection to off-stream wetland habitats, which increase food resources (waterbugs) available for fish and native animals
Winter/spring fresh (one fresh of more than 5,000 ML/day for two days during July to September in reach 1)	Encourage female platypus to select a nesting burrow higher up the bank to reduce the risk of higher flow later in the year flooding the burrow when juveniles are present Scour fine sediment from the gravel bed and riffle substrate Maintain existing beds of in-channel vegetation
Winter/spring off-stream habitat flow trial (one fresh of up to 6,000 ML/ day for three days during May to June 2023 in reach 1)	Maintain off-stream habitat for small-bodied native fish and platypus Scour fine sediment from the gravel bed and riffle substrate Maintain existing beds of in-channel vegetation Connect lower Goulburn River wetlands and anabranches to the river channel
Goulburn River reaches 4 and 5
Year-round low flow (600-800 ML/day in reach 4 and 600 - 1,000 ML/day in reach 5)	Provide slow, shallow habitat required for the recruitment of larvae/juvenile fish and habitat for adult small-bodied fish Provide deep-water habitat for large-bodied fish Submerge snags and littoral vegetation to provide habitat for fish and waterbugs and a substrate for biofilms to grow Provide habitat and food for turtles Maintain habitat for aquatic vegetation and water the root zone of low-bank vegetation Vary flow within a specified range to encourage plankton production for food, disrupt biofilms and maintain water quality Low, variable flow to enable vegetation to establish to protect against notching and bank erosion
Winter/autumn fresh (one fresh of more than 7,300 ML/day for two days in reaches 4 and 5 during July to August 2022 and May to June 2023)	Provide organic matter and carbon (e.g. leaf litter) to the channel Provide connectivity to off-channel habitats and through the river for fish dispersal and greater food resources Scour bed sediments to maintain pools and change in-channel complexity to improve habitat Provide cues for platypus to nest higher up the bank Provide sediment and plant propagules from tributary inflows after large rain events to encourage the establishment of new plants Inundate and reduce terrestrial vegetation on low banks and trigger the recruitment of native, flood-tolerant streamside vegetation Improve waterbug habitat and food availability by scouring fine sediments
Pass a portion of the natural tributary flow in the mid-Goulburn to reaches 4 and 5 when flow in reach 3 is above 4,000 ML/day (1,000 - 5,000 ML/day in reaches 4 and 5 during May and October)	Provide organic matter and carbon (e.g. leaf litter) to the channel Transport and deposit seed, sediment and plant propagules on the riverbank
Early-spring fresh (one fresh of up to 10,500 ML/ day with more than seven days above 7,300 ML/day during September and October in reaches 4 and 5)	Provide organic matter and carbon (e.g. leaf litter) to the channel Provide connectivity to off-channel habitats and through the river for fish dispersal and greater food resources Scour bed sediments to maintain pools and change in-channel complexity for improved habitat Increase soil moisture in banks to improve the condition of existing native vegetation Provide sediment and plant propagules from tributary inflows after large rain events to encourage the establishment of new plants Inundate and reduce terrestrial vegetation on low banks and trigger the recruitment of native flood-tolerant streamside vegetation Improve waterbug habitat and food availability by scouring fine sediments and biofilms from hard substrates
Late-spring fresh (one fresh of more than 6,000 ML/day for two days during November and December in reaches 4 and 5)	Stimulate spawning of golden and silver perch Scour bed sediments to maintain pools and change in-channel complexity for improved habitat Improve waterbug habitat and food availability by scouring fine sediments and biofilms from hard substrates
Autumn fresh (one fresh of more than 5,700 ML/ day for two to five days during March and May in reaches 4 and 5)	Cue fish to move into and through the system to increase their abundance and dispersal Scour bed sediments to maintain pools, and change in-channel complexity for improved habitat Increase soil moisture in banks for existing vegetation maintenance Scour old biofilm from hard substrates to allow new biofilm growth to improve food and habitat for macroinvertebrates
Slow recession of unregulated flow or releases from Goulburn Weir (3,000 ML/day and below in summer/autumn and from 6,000 ML/ day in winter/spring in reaches 4 and 5)	Minimise the risk of bank erosion associated with a rapid reduction in the water level Transport and deposit seed, plant propagules and sediment on the riverbank Minimise the risk of hypoxic blackwater after natural events

Scenario planning

Table 5.4.2 outlines potential environmental watering and expected water use under a range of planning scenarios.

The recently updated environmental flows study for the Goulburn River recommends a range of watering actions that are needed most years to achieve the target environmental outcomes. High water availability in the Goulburn system at the end of 2021-22 and a strong resource outlook for 2022-23 mean all recommended watering actions can potentially be met, even under a return to dry conditions. Therefore, the proposed actions are the same for all planning scenarios in 2022-23.

Providing year-round low flow in all reaches of the Goulburn River is the highest priority under all climate scenarios. Year-round low flow in the mid-Goulburn river (reach 1) maintains habitat for fish, platypus, turtles and waterbugs, and it also ensures in- stream vegetation remains inundated and persists through the non-irrigation season when operational flow ceases. Year-round low flow in the lower Goulburn River (reaches 4 and 5) provides habitat for fish and macroinvertebrates and helps lower bank vegetation to recover following multiple years of high operational flows during warmer months. Water for the environment in the lower Goulburn River continues to focus on vegetation recovery, to improve the condition of the lower banks that showed signs of recovery in 2021-22 following lower-than-normal demand for IVTs. Goulburn-Murray Water generally diverts a proportion of the natural high flow from Goulburn Weir into the Waranga Basin. These operational transfers can cause the flow rate in the lower Goulburn River to drop rapidly after a natural high-flow event. Water for the environment may be used as required to slow the recession of natural spills at Goulburn Weir, reduce the risk of bank slumping, improve water quality and provide a more natural flow pattern for native fish.

Delivering a winter/autumn fresh in reaches 4 and 5 is a high priority under all climate scenarios to scour bed sediments, support channel-forming processes and improve habitat. In reach 1, a winter/spring fresh is a high priority under all scenarios to cue platypus to nest higher up the bank.

A winter/spring off-stream habitat flow trial is proposed in 2022-23 to connect low-lying wetlands and anabranches to the main river channel. Operational flows delivered from Lake Eildon mean these habitats are often wet in the summer months when they should be drawing down, and they dry through the winter months when they should be filling. The flow trial will assess ecological responses to a more natural watering regime and inform how infrastructure could be used to implement better water regimes in the future. The flow trial is a partnership project between Goulburn Broken CMA and the Taungurung Land and Waters Council, and it aims to boost environmental and Traditional Owner outcomes.

Timing deliveries of water for the environment alongside natural-flow events will again be a focus for 2022-23. Passing tributary flows from the mid-Goulburn River to the lower Goulburn River to provide variability through winter and spring is a high priority under all scenarios. Tributary flows following high-rainfall events carry more plant seed, nutrients and sediments that are beneficial to the lower Goulburn River than water released from Lake Eildon.

An early-spring fresh to prime the system and stimulate plant germination is a high priority under all climate scenarios. A late- spring fresh to trigger perch spawning is a tier 2 priority under all scenarios. Golden and silver perch are long-lived species that do not need to spawn annually to maintain good populations, and events delivered in November 2020 and 2021 achieved good spawning outcomes in the lower Goulburn River. However, if bank vegetation on the lower banks has had sufficient time to establish and is in good condition, or high natural flows have delayed germination, a late-spring fresh could be delivered under below-average to wet scenarios in 2022. There may not be sufficient water to deliver a late-spring fresh under drought and dry scenarios. If summer low-flow targets are met (that is, if IVTs are not too high), an autumn fresh will be delivered between March and May 2023 to maintain the bank vegetation and allow new seeds to germinate and provide a cue for native fish to move into the lower Goulburn River from the Murray River.

Carrying over water to meet minimum low-flow objectives from July 2023 to September 2024 is an important consideration under drought and dry climate scenarios but is less important under average and wet scenarios due to likely high early-season allocations.

Planning scenario table

Table 5.4.2 Potential environmental watering for the Goulburn River under a range of planning scenarios

Planning scenario	Drought	Dry	Below average	Average	Wet
Expected river conditions	Very few or no large natural- flow events Blackwater could be an issue if there is a large rain event in the warmer months	One to two short-duration, large, natural flow events are likely to provide small winter/ spring freshes Blackwater could be an issue if there is a large rain event in the warmer months	Large natural- flow events are expected to provide some low flow for a few months from winter/ mid-spring and are likely to provide small winter/spring freshes Blackwater could be an issue if there is a large rain event in the warmer months	Large natural- flow events will provide low flow for most of the year and will likely provide winter/ spring freshes Blackwater could be an issue if there is a large rain event in the warmer months	Large natural- flow events will provide low flow and multiple freshes and/ or overbank flow events in winter/spring
Expected availability of water for the environment¹	438 GL	567 GL	567 GL	567 GL	567 GL
Goulburn River (targeting reach 1)
Potential environmental watering – tier 1 (high priorities)²	Tier 1a (can be achieved with predicted supply)
	Year-round low flow Winter/spring fresh Winter/spring off-stream habitat flow trial	Year-round low flow Winter/spring fresh Winter/spring off-stream habitat flow trial	Year-round low flow Winter/spring fresh Winter/spring off-stream habitat flow trial	Year-round low flow Winter/spring fresh Winter/spring off-stream habitat flow trial	Year-round low flow Winter/spring fresh Winter/spring off-stream habitat flow trial
Goulburn River (targeting reaches 4 and 5)
Potential environmental watering – tier 1 (high priorities)³	Tier 1a (can be achieved with predicted supply)
	Year-round low flow Winter/autumn fresh Pass mid- Goulburn tributary flows Early-spring fresh Autumn fresh Recession flow management	Year-round low flow Winter/autumn fresh Pass mid- Goulburn tributary flows Early-spring fresh Autumn fresh Recession flow management	Year-round low flow Winter/autumn fresh Pass mid- Goulburn tributary flows Early-spring fresh Autumn fresh Recession flow management	Year-round low flow Winter/autumn fresh Pass mid- Goulburn tributary flows Early-spring fresh Autumn fresh Recession flow management	Year-round low flow Winter/autumn fresh Pass mid- Goulburn tributary flows Early-spring fresh Autumn fresh Recession flow management
Potential environmental watering – tier 2 (additional priorities)²	Late-spring fresh	Late-spring fresh	Late-spring fresh	Late-spring fresh	Late-spring fresh
Possible volume of water for the environment required to achieve objectives	390,000 (tier 1a) 50,000 ML (tier 2)	515,000 (tier 1a) 50,000 ML (tier 2)	505,000 (tier 1a) 50,000 ML (tier 2)	515,000 ML (tier 1a) 50,000 ML (tier 2)	420,000 ML (tier 1a) 50,000 ML (tier 2)
Priority carryover requirements for 2023-24	23,000 ML		0 ML

¹ When trading opportunities are available, additional allocations of water for the environment from the Murray River can be transferred to meet Goulburn demand.
² A winter/spring off-stream habitat flow trial fresh is not required in 2023 if delivered in May to June 2022.
³ Preceding low-flow periods and bank vegetation condition triggers must be met before delivery of late-spring and autumn freshes are considered.

Engagement

Table 2 shows the partners and stakeholder organisations that Goulburn Broken CMA engaged when preparing the Goulburn River and Goulburn 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 Goulburn Broken Regional Catchment Strategy and Goulburn Broken Waterway Strategy.

Table 2 Partners and stakeholders engaged in developing the Goulburn system seasonal watering proposal

Partner and stakeholder engagement
Goulburn Valley Environment Group Common- wealth Environmental Water Office Goulburn- Murray Water Murray- Darling Basin Authority Parks Victoria Individual landholders who are on the Goulburn Environmental Water Advisory Group Local ecotourism operator Trelly’s Outdoor Staff from the Monitoring, Evaluation and Research Program, Goulburn River (Com- monwealth Environmental Water Office program) Taungurung Land and Waters Council Yorta Yorta Nation Aboriginal Corporation

Partner and stakeholder engagement

Goulburn Valley Environment Group
Common- wealth Environmental Water Office
Goulburn- Murray Water
Murray- Darling Basin Authority
Parks Victoria
Individual landholders who are on the Goulburn Environmental Water Advisory Group
Local ecotourism operator
Trelly’s Outdoor
Staff from the Monitoring, Evaluation and Research Program, Goulburn River (Com- monwealth Environmental Water Office program)
Taungurung Land and Waters Council
Yorta Yorta Nation Aboriginal Corporation

Page last updated: 01/12/22