Skip to content

Close to Tullamarine Airport, Jacksons Creek (flowing from the west) and Deep Creek (flowing from the north) join to form the Maribyrnong River at Keilor North. The river runs south through Yarraville in inner Melbourne before meeting the Yarra and flowing into Port Phillip Bay. Rosslynne Reservoir near Gisborne is the largest storage in the system and harvests water from the headwaters of Jacksons Creek

Rosslynne Reservoir is the only major storage in the Maribyrnong catchment, and it is located in the upper reaches of Jacksons Creek. The priority river reaches for environmental watering in the Maribyrnong system are reaches 6 and 7 (upper and lower Jacksons Creek respectively), downstream of Rosslynne Reservoir. The release capacity of 20 ML/day from Rosslynne Reservoir is a significant constraint on what can be achieved by environmental deliveries.

The VEWH does not hold an environmental entitlement in the Maribyrnong system and depends on temporary trade to meet demands. Over the past four years, Melbourne Water and the VEWH have worked with local diversion licence holders to purchase unused water that can then be delivered specifically for environmental outcomes in the system. This arrangement is negotiated each year and will only occur with the agreement of all parties involved.

Environmental watering objectives in the Maribyrnong River

Plant icon
Maintain or rehabilitate in-stream vegetation and reduce invasive terrestrial vegetation populations
Fish icon
Allow for the passage of small-bodied fish through the system
Insect icon
Maintain waterbug habitat by providing suitable depth over riffles
Water icon
Maintain water quality, particularly dissolvedoxygen levels, by flushing pools

Environmental values

The upper Maribyrnong catchment contains areas of intact streamside vegetation, which provide important habitat for native fish including migratory short-finned eels, common and ornate galaxias, flathead gudgeon, tupong and Australian smelt. There are highly diverse community of waterbugs and a significant platypus population in several reaches of the system.

Social, cultural and economic values

The Maribyrnong River is located in the western suburbs of Melbourne and provides water (primarily from Rosslynne Reservoir on Jacksons Creek) to urban and rural users.

The river provides many recreational opportunities (such as boating, fishing, cycling, walking and picnicking in the adjacent parklands). The river at Keilor provides good canoeing and has three ponding points, designed to enable children and adults to catch fish with a hand net. There are nine boat landings along the river (most notably at Canning Reserve, Maribyrnong Park and Fairbairn Park) and the rivers hosts water-based events such as the University of Melbourne intercollegiate regatta, Canoeing Victoria's Winter Marathon Series and Scouts Australia paddling events.

Fishing is popular from jetties and fishing platforms along the parks and reserves on either side of the river. A popular walking track skirts the river and bicycle tracks follow the riverbanks and cross the river via pedestrian bridges at several points along the river's length.

The waterways of the Maribyrnong system hold significance for the Wurundjeri and Boon Wurrung (Bunurong) people, who are the Traditional Owners in the region, with Aboriginal people frequenting its banks for at least 40,000 years.

Conditions mid-2017

Between 2012 and 2015, rainfall and run-off into the waterways of the Maribyrnong system decreased with the drier conditions. Spring 2016 saw a return of wetter conditions with multiple high-flow events, particularly in reach 7. Flows in reach 6 were lower because Rosslynne Reservoir captures a high proportion of upstream flows and there are few tributaries to deliver unregulated flows immediately downstream of the storage. Despite the wet conditions, most winter/spring flow targets were either not met or only partially met.

Conditions dried over summer and into autumn, and environmental water was delivered to provide freshes to the waterway. These events were timed for March and May to improve water quality — particularly oxygen levels, which are essential for waterbugs, fish and platypus. The events also refreshed pools, improved fish passage and supported aquatic plants.

Scope of environmental watering

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

Potential environmental watering1

Environmental objectives

Summer/autumn freshes (up to 3 events of 20–40 ML/day for up to 7 days) in December–May

  • Maintain water quality by flushing pools
  • Support the in-stream vegetation
  • Provide passage for smallbodied native fish

Summer/autumn low flows (4–6 ML/day) in December–May

  • Maintain waterbug habitat by providing suitable depth
    over riffles

Winter/spring low flows (20–40 ML/day) in June– November

  • Maintain or rehabilitate in-stream vegetation and disturb invasive terrestrial vegetation populations
  • Allow for the passage of small-bodied fish through the system

1 The range in flow requirements represent the target flow requirements for reaches 6 and 7.

Risk management

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

Engagement

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.

Communities in the Melbourne region are involved in decisions about the Tarago, Yarra and Werribee river systems through each system's Environmental Water Advisory Group.

Who is engaged and how

Recreational users

Through formal advisory groups coordinated by Melbourne Water, representatives of recreational user groups are engaged. Advisory group members receive notifications about planned environmental water deliveries via the community bulletin.

For recreational users, safety related to higher water levels are a key concern.

On occasion, Melbourne Water informs recreational users directly about environmental watering (such as the Werribee fishing club or Canoes Victoria).

Environment groups

Representatives of environment groups are engaged through formal advisory groups coordinated by Melbourne Water. Advisory group members receive notifications about planned environmental water deliveries via the community bulletin.

Melbourne Water has informal relationships with various environment groups (such as Landcare, Birdlife Australia, Yarra Riverkeepers, Environment Victoria and Waterwatch) and meet with these groups on an as-needs basis.

Some groups, such as Waterwatch, share monitoring information with Melbourne Water.

Landholders/farmers

Through the Yarra Diversions newsletter, diversions licence holders receive information and updates on environmental watering.

Landholders and farmers are engaged through formal advisory groups coordinated by Melbourne Water. Advisory group members receive notifications about planned environmental water deliveries via the community bulletin.

Traditional Owners

Melbourne Water is doing a collaborative project with the Wurundjeri Tribe Land and Compensation Heritage Council and the Victorian Environmental Water Holder to document the Wurundjeri cultural values in the Yarra river system. The aim of this project is to increase understanding of values that can be supported with environmental water to achieve shared benefits for Aboriginal people from environmental watering (Aboriginal environmental outcomes).

Councils

Through formal advisory groups coordinated by Melbourne Water, Council representatives (from various local councils across region) are engaged. Advisory group members receive notifications about planned environmental water deliveries via the community bulletin.

Melbourne Water publishes an annual two-pager for each Council about activities undertaken in their catchment, including delivery of environmental flows.

General public

Melbourne Water communicates and engages with the general public through their website, media releases and Facebook and Twitter. Melbourne Water community bulletins are posted on their webpage, Facebook and Twitter, and issued to media contacts.