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Birchs Creek is part of the broader Bullarook system, which contains two small storages – Newlyn Reservoir and Hepburn Lagoon – that provide water for irrigation and urban supply. The storages fill and spill during winter or spring in years with average or above-average rainfall. The VEWH holds water for the environment in Newlyn Reservoir, but there is no water held in Hepburn Lagoon.

Birchs Creek receives tributary inflows from Rocky Lead, Langdons, Lawrence and Tourello creeks. Groundwater provides reliable baseflows to the downstream reaches of Birchs Creek in most years.

The VEWH is allocated 100 ML in Newlyn Reservoir on 1 December each year, provided that seasonal determinations in the Bullarook system are at least 20 percent. Any unused allocation from 1 December can be carried over until 30 November
of the following water year, but if Newlyn Reservoir spills from 1 July to 30 November, the volume held in carryover is lost. Any water remaining on 30 November is forfeited. When seasonal determinations are below 20 percent, the VEWH does not receive an allocation, and the system’s resources are used to protect essential human needs.

Traditional Owners
Storage manager
Environmental water holder

Environmental watering objectives in Birchs Creek

Maintain the abundance and diversity of small- and medium-bodied native fish, including river blackfish, mountain galaxias, flat-headed gudgeon and Australian smelt
Platypus icon
Maintain the platypus population and improve its resilience to future droughts and floods
Plant icon
Maintain the diversity and abundance of in-stream aquatic plants

Maintain a diverse variety of fringing and streamside native vegetation communities
Insect icon
Maintain the population of waterbugs and the diversity of functional groups to drive productive and dynamic food webs
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Maintain water quality to support aquatic life and ecological processes

Environmental values

Birchs Creek supports threatened aquatic plants, and its deep pools provide habitat for aquatic animals during dry periods. The creek contains native fish, including regionally significant populations of river blackfish and mountain galaxias, as well as flat-headed gudgeon and Australian smelt. Recent monitoring indicates that platypus are present throughout the entire creek.

Traditional Owner cultural values and uses

Birchs Creek is recognised as Dja Dja Wurrung Country. The Djaara (Dja Dja Wurrung people) Nation Statement in Water is Life and the Dhelkunya Dja (Healing Country) Country Plan 2014-2034 both describe their objectives around the management of water on their Country.

In planning for environmental flows in Birchs Creek, the Dja Dja Wurrung Clans Aboriginal Corporation (trading as Djaara) and the North Central CMA have identified the creek as a potential site for future projects.

The North Central CMA and Djaara continue to work towards increased engagement in planning and delivering environmental water, including identifying opportunities for Dja Dja Wurrung to play a greater role in its management and administration.

Social, recreational and economic values and uses

In planning the potential environmental watering actions in Table 5.7.5, the North Central CMA considered how environmental flows could support values and uses, including:

  • water-based recreation (such as fishing)
  • riverside recreation and amenity (such as cycling and walking [particularly in Newlyn, Smeaton and Clunes] and improved amenity at key community spaces like Andersons Mill)
  • improved water quality (such as for domestic and stock use)
  • socioeconomic benefits (such as increased tourism and visitation to key community spaces).

Scope of environmental watering

The term ‘environmental watering’ refers to the active delivery of held environmental water to support particular environmental objectives by altering the flow in a river or the water level in a wetland. While other terms are sometimes used to describe the delivery of environmental water, ‘environmental watering’ is deliberately used here and in seasonal watering statements to ensure consistency in the legal instruments that authorise the use of water for the environment in Victoria.

Table 5.7.5 describes the potential environmental watering actions in 2023-24, their expected watering effect (that is, the intended physical or biological effects of the watering action) and the longer-term environmental objectives they support. Each environmental objective relies on one or more potential environmental watering actions and their associated physical or biological effects.

Table 5.7.5 Potential environmental watering actions, expected watering effects and associated environmental objectives for Birchs Creek

Potential environmental watering

Expected watering effects

Environmental objectives

Birchs Creek (targeting reach 2)1

Winter/spring fresh (one fresh of 27 ML/day for three days during June to November)

  • Maintain and support the growth and germination of streamside vegetation by increasing soil moisture and depositing sediment on the bank and benches
  • Scour old biofilms and organic matter that has accumulated in the channel, and cycle nutrients throughout the creek
  • Improve water quality by freshening refuge pools and provide connectivity between pools for fish and platypus movement
Fish iconPlant iconWater drop iconPlatypus iconInsect icon

Summer/autumn freshes (three freshes of 10-15 ML/ day for three days during December to May)

  • Increase the water depth to maintain and support seed germination and the growth of in-stream aquatic vegetation
  • Top up pools to refresh water quality (particularly oxygen levels) and enhance connectivity between pools for fish and platypus movement
Fish iconPlant iconWater drop iconPlatypus icon

1 Environmental flows target outcomes in reach 3, but compliance can only be assessed in reach 2.

Page last updated: 01/07/22