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The construction and operation of Lake Eppalock has significantly altered downstream river flows and reversed seasonal flows. Lake Eppalock captures rainfall run-off and reduces natural winter and spring flows downstream. The stored water is then released at a higher-than-natural rate over summer and autumn to meet downstream irrigation demand in the reaches between Lake Eppalock and the Campaspe Siphon. Environmental water is held and released from Lake Eppalock, with some limited ability to regulate flows further downstream at the Campaspe Weir. 

Higher-than-natural flows throughout summer may reduce the amount of suitable habitat for juvenile fish, which rely on protected shallow areas of water near the edge of the river channel. Delivering water to users downstream in the River Murray when they need it over summer is essential, and storage managers and the CMA have been working together to limit any negative effects these transfers may have on native plants and animals. 

Providing the target flows in all reaches below Lake Eppalock is important. Environmental water is usually released from Lake Eppalock to meet specific flow targets in reach 4 (that is, downstream of Rochester). These flows also achieve the desired flow objectives in reaches 2 and 3 between Lake Eppalock and Rochester. Primary flow measurement points are at Barnadown (reach 2) and downstream of the Campaspe siphon (reach 4). In specific circumstances, water can be delivered to reach 4 from the Goulburn system via the Waranga western main channel.

System map

Campaspe System
Grey river reaches have been included for context. The numbered reaches indicate where relevant environmental flow studies have been undertaken. Coloured reaches can receive environmental water.

Environmental watering objectives in the Campaspe River

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Provide connection along the length of the Campaspe River and into the River Murray
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Sustain adult river red gums and encourage the growth of new plants
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Provide habitat to help protect and boost populations of native fish

Help native fish species (such as the trout cod, river blackfish and Macquarie perch) recolonise the river
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Increase the diversity and biomass of waterbugs to provide energy, break down dead organic matter and support the river’s food chain
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Maintain and increase the cover of in-stream and riverside plants
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Maintain the resident platypus population by providing places to rest, breed and feed, as well as opportunities for juveniles to disperse to the River Murray
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Prevent high salinity and maintain healthy levels of oxygen in deep pools

Environmental values

The Campaspe River below Lake Eppalock provides important habitat for several fish species including Murray cod, silver perch, golden perch, Murray–Darling rainbowfish and flat-headed gudgeon. Maintaining flows is important for migration opportunities and dispersal of these native fish species and juvenile platypus. Turtles and frogs are also present and the intact river red gum canopy along the riverbanks supports terrestrial species (such as the squirrel glider).

Social, cultural and economic values

The Campaspe River is an important source of water and a delivery mechanism for irrigation and town water. Popular recreational activities along the Campaspe River include camping, boating, kayaking, fishing, swimming, bushwalking, picnicking and birdwatching. These activities draw locals and tourists alike, providing economic benefits to towns along the river. The Campaspe River is culturally significant with many Aboriginal cultural heritage sites including shell deposits, scar trees, mounds and artefacts recorded along the banks. The Campaspe River continues to be a place of significance for Traditional Owner groups and Nations in the region including the Dja Dja Wurrung, Taungurung and Yorta Yorta people.

Conditions mid-2017

The Campaspe River has suffered from extreme climatic events over the last 15 years including the Millennium Drought and record floods in January 2011. Most of the recommended environmental flows could not be delivered between 2005 and 2010 because of very low rainfall and inflows to Lake Eppalock, and the ecological condition of the river declined. The 2011 flood scoured most of the established in-stream vegetation and riparian vegetation from the banks of the river. Conditions have been relatively normal since, but 2015–16 was quite dry and there was low water availability at the beginning 2016–17, with allocations starting at zero.

A small volume of water carried over from 2015–16 was used to provide winter low flows at the beginning of 2016– 17 before conditions became very wet, causing high inflows to Lake Eppalock, which began to spill on 3 October 2016. Unregulated flows from tributaries downstream of Lake Eppalock and storage spills provided high flows to all reaches during winter and spring, meaning there was no need to release additional environmental water for much of this period. During the spill from Lake Eppalock, an overbank flow event occurred that helped to maintain the river form by scouring sediment from pools and riffles and by improving riparian vegetation. Rainfall throughout the rest of 2016–17 was variable, with a return to drier conditions again toward the end of the year.

Environmental water was delivered in accordance with a wet scenario. This aimed to optimise the benefit of high river flows to maintain and improve environmental values including native fish and bank vegetation and to increase the resilience of the river to cope with stress in future. Monitoring showed an improvement in the native fish community with increasing numbers and range of golden and silver perch throughout the river and high numbers of Murray–Darling rainbowfish. Fewer carp were recorded in reaches that had increased numbers of golden perch. To support native fish, environmental water was used to provide summer low flows targeting the lower reaches of the river to prevent high salinity and low-dissolved-oxygen concentrations and consequent impacts on native fish. Deliveries of water to downstream users in the River Murray in summer and autumn were managed by the storage operator and the CMA to achieve a series of summer and autumn freshes. Low flows in winter were also provided with a combination of environmental water and unregulated flows to allow fish to move between habitats, increase the abundance of waterbug habitat and improve water quality.

Scope of environmental planning

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

Potential environmental watering

Environmental objectives

Summer/autumn low flows (10–50 ML/day in December–May)

  • Maintain aquatic vegetation
  • Maintain fish habitat and reinstate slack waters (areas with minimal water movement)
  • Limit the effect of cold water pollution from Lake Eppalock on fish
  • Maintain access to riffle habitat and water quality for waterbugs
  • Maintain permanent connectivity for water quality
  • Maintain permanent connectivity for platypus movement

Winter/spring freshes (up to 2 events at 1,000–1,800 ML/day for up to 7 days each in June– November)

  • Reduce encroachment by exotic and terrestrial vegetation
  • Enhance river red gum recruitment
  • Stimulate fish movement, allow movement to downstream reaches and provide spawning triggers
  • Flush and mix river pools for water quality
  • Flush organics from the bank and benches to reduce the risk of blackwater events in summer
  • Mix and flush river pools for waterbugs
  • Inundate additional snags and flush sediment off biofilms (groups of microorganisms) for waterbugs
  • Support platypus habitat and breeding including triggers for burrow selection

Winter/spring low flows (50–200 ML/day [or natural1], in June–November)

  • Provide longitudinal connectivity for fish
  • Maintain access to riffle habitat and water quality for waterbugs
  • Maintain permanent longitudinal connectivity of river for improved water quality
  • Facilitate platypus habitat and breeding opportunities

Summer/autumn freshes (up to 3 freshes of 50–200 ML/day for up to 3 days each in December–May)

  • Maintain riparian and in-channel recruitment vegetation
  • Increase extent of / maintain in-stream aquatic vegetation
  • Provide longitudinal connectivity for fish in periods of low flows
  • Maintain waterbug habitat and wash organic matter into the river to drive aquatic food webs
  • Respond to blackwater events as required

1 'Or natural' means that flow rates may be above or below the specified target rates depending on inflows and climatic conditions.

Risk management

In preparing its seasonal watering proposal, North Central CMA considered and assessed the risks of environmental watering and identified mitigation strategies. Program partners continually reassess risks and mitigation actions throughout the water year


Waterway managers meet communities on environmental watering regionally, although other program partners also play a role.

In each region of Victoria, community engagement on environmental watering happens when environmental watering objectives and priorities are scoped (long term and annually), when delivering environmental water, and when reporting on environmental watering results.

In the North Central region communities are involved in decisions about the Loddon and Campaspe river systems, Murray river system including Gunbower Forest and some of the wetlands connected by the Wimmera-Mallee pipeline. This happens through formal advisory groups: Environmental Water Advisory Groups including river and wetland focused groups and the Gunbower Island Community Reference Group.

Who is engaged and how

Recreational users

Through formal advisory groups, recreational users provide local advice and raise opportunities for potential 'shared benefits' from environmental watering. Through Environmental Water Advisory Groups, recreational users are informed of environmental water deliveries and provide data that assists with reporting on the outcomes of environmental watering.

Goulburn-Murray Water engages with recreational user groups (such as Save Lake Eppalock and Lake Meran Users Group) that use water storages for recreation through planned consultations and meetings to discuss storage levels and potential impacts of environmental water releases from storages.

Environment groups

Through formal advisory groups, environment groups provide local knowledge, land management advice and advocate for the environment. They are also informed of environmental water deliveries and provide data that assists with reporting on the outcomes of environmental watering (including citizen science monitoring data such as providing bird counts).


Through formal advisory groups, farmers and landholders (including those who own private wetlands that receive environmental water) provide local knowledge and land management advice regarding environmental watering.

They are also informed of environmental water deliveries and provide data that assists with reporting on the outcomes of environmental watering. Goulburn-Murray Water engages (and often) with consumptive entitlement holders (often irrigators) and landholders (often with river frontages).

Traditional Owners

Through the North Central Catchment Management Authority Indigenous Facilitator, Traditional Owners from the Barapa Barapa, Dja Dja Wurrung and Yorta Yorta Nations are given the opportunity to provide input to seasonal watering proposals. The Catchment Management Authority and the Barapa Barapa Nation have conducted a cultural values mapping project in Gunbower Forest which will eventually enable cultural values to be incorporated in Gunbower environmental water planning. The Barapa Barapa and Yorta Yorta Nations undertake monitoring of cultural values in Gunbower Forest.

There are Dja Dja Wurrung and Yorta Yorta representatives from the North Central region who are members of the Murray Lower Darling Rivers Indigenous Nations. The Victorian Environmental Water Holder, the Commonwealth Environmental Water Holder and the Murray Darling Basin Authority engage the Murray Lower Darling Rivers Indigenous Nations on strategic (often longer term) issues related to environmental watering.


Councils are invited to participate in formal advisory groups meetings. Goulburn-Murray Water  consults with the City of Greater Bendigo, Gannawarra Shire and Swan Hill Rural City Council regularly on water management, including on environmental water management.

General public

The North Central Catchment Management Authority communicates and engages with the general public through their website, media releases, newsletters, public notices, community forums, community events (such as tours of Gunbower Forest during environmental watering), social media and direct contact to interested parties by email distribution list.