Copy
View this email in your browser
AUTUMN EDITION 2022

TRADITIONAL OWNER ACKNOWLEDGEMENT

The Corangamite Catchment Management Authority acknowledges the Traditional Owners of the land and waters of the Upper Barwon River, the Eastern Maar People.  We pay our respects to their Elders past, present and emerging. We are committed to continuing to work in partnership with the Eastern Maar Aboriginal Corporation to ensure their aspirations for the restoration and protection of the Barwon River are achieved.

 

THE UPPER BARWON RIVER

The Corangamite Catchment Management Authority (CMA) has identified the Upper Barwon River as the focus for investment as part of our Barwon Flagship Waterway project. Flagship waterways are large-scale long term rehabilitation projects happening across the state of Victoria, addressing waterway and catchment health.

The Barwon River was identified in Water for Victoria (2016) as a priority waterway within the region. This project is consistent with the Barwon Ministerial Advisory Committee (Barwon MAC) discussion paper and the recently released Rivers of the Barwon (Barre Warre Yulluk) Action Plan.

The Barwon Flagship Project will be delivered as a large scale, long term (30 year) project. During 2022 - 2024 the initial focus of the Flagship Project in the Upper Barwon is about working together with landholders, key agencies, and community groups to develop and implement strategies to enhance riparian management practices and improve the delivery of environmental water further down the Barwon River.

We have just launched the new Barwon Flagship Project webpage where you will find more information, and this will be updated over time: Barwon Flagship Waterway - Corangamite Catchment Management Authority (ccma.vic.gov.au)

BARWON FLAGSHIP PROJECT COORDINATOR 

Corangamite CMA Project Officer Amanda May will be coordinating and communicating all the Barwon Flagship activities along the waterway to make sure the Corangamite CMA are always building towards and maintaining a healthy river and community.

Amanda can be contacted by email amanda.may@ccma.vic.gov.au or mobile 0478 093 998

Keep an eye on your inbox to see how Amanda and the Corangamite CMA are working towards projects that will improve life on the Barwon and learn more about how you can get involved!

 

WHAT PROGRAM OF WORKS MAKES UP THE BARWON FLAGSHIP  

 

During 2022 - 2024 the initial focus of the Barwon Flagship Project is the Upper Barwon and is about working together with landholders, key agencies, and community groups to develop and trial strategies that can be applied to priority Willow (Salix spp) and Reed sweet Grass (Glyceria maxima) chokes using riparian management practices. This will improve the delivery of environmental water within the Upper Barwon and further down the Barwon River.
 

RIPARIAN WORKS

Riparian land is the ‘buffer zone’ between water and land. The land could be used for anything from a recreation reserve to an area for livestock to graze. 

It's important to keep riparian land healthy and well covered with vegetation to help maintain a healthy waterway.  This is of particular relevance to the Barwon River as the catchment is highly modified which adversely impacts the quality and flow of water in the river.


Healthy riparian areas have many benefits to landholders including improved water quality for stock, increased land value, and contribute to nature conservation.
 


Interaction of land and water in the riparian zone (Lovett and Price, 1999)

WATERWAY PROTECTION PROGRAM 

Currently the Corangamite CMA Waterway Protection Program is finalising applications for funding for a recent Expression of Interest (EOI) process. Incentives are available through this program for fencing, weed control, revegetation, stock crossings and off-stream water points, willow removal and pest animal management. The successful applicants will be announced at the end of the month. 
 

FLAGSHIP RIPARIAN PROGRAM 

Flagship riparian works are a new program and will focus on trialling site specific, innovative approaches, developed in collaboration with land managers. Opportunities for demonstration sites are being investigated and these will be further explored at the open house sessions scheduled for June (more detail in ‘Events’ section, below).
 

RECOGNISING GLYCERIA MAXIMA 

Glyceria maxima or Reed Sweet Grass is a highly invasive grass species which creates a dense floating monoculture, reducing biodiversity, dam capacity and increases flood risk. 



Glyceria seed head (Source: Florabase WA)
 

Glyceria thrives in temperate climates with full sun, access to high levels of nutrients, in slow moving water columns at a depth of 0.5 to 1.5 meters. The best control methods are to suppress its growth long-term – this is achieved by shading and increased summer flows in rivers; and maintain the natural vegetation – Glyceria doesn’t grow underneath dense stands of vegetation, even small buffers of vegetation will reduce the density of Glyceria and therefore its impact on the system.

Small infestations should be treated ASAP. If you think you may have Glyceria on your property, please contact Angus Donaldson on angus.donaldson@ccma.vic.gov.au or 0409 794 234.

For further resources on this invasive species please see:
https://florabase.dpaw.wa.gov.au/browse/profile/437

http://vro.agriculture.vic.gov.au/dpi/vro/vrosite.nsf/0d08cd6930912d1e4a2567d2002579cb/4d29328e075999fdca2578c300771ac0?OpenDocument

E-WATER - WHAT IS 'WATER FOR THE ENVIRONMENT'?

 

The Ornithorhynchus anatinus or Platypus can be found in the waters of the Upper Barwon


The Upper Barwon River Environmental Entitlement 2018 is delivered by the Corangamite CMA, on behalf of the Victorian Environmental Water Holder (VEWH). The water is released in carefully timed flows to give a helping hand to native plants and animals, including fish, frogs, and platypus. It also maintains water quality and improves native in-stream and riverside vegetation. We call this water ‘environmental releases’ or ‘water for the environment’, and it is in addition to natural flows and Barwon Water’s passing flows.

“Passing Flow” is water that is required by law to be released from dams by water authorities to maintain some flow in the river downstream, as water is harvested from the river. Passing flow is separate to ‘water for the environment’ held in an Environmental Entitlement, but also helps maintain environmental values and other community benefits.

Environmental releases are based on scientific FLOWS studies (a method for determining environmental water requirements in Victoria ) to maintain life dependant on the r
iver. Water for the environment can be constant low flows down the river or pulses of water to trigger fish migration. 

Due to weed infestations (Willows and Glyceria) there was short-term unintended floodplain inundation with some of the first releases of water between 2019 and 2021.  Consultation with affected landholders resulted in the daily volume of water releases being reduced to avoid this impact. Reductions to the daily volumes of water released will stay in place until weed infestations are addressed, limiting the ability to release higher pulses of water to flush sediments and assist with fish migration. It is important to note that higher flows and floodplain inundation can still occur because of local rainfall events, and that under these conditions, environmental water releases would be ceased.


We measure environmental releases in Megalitres (ML) per day.
How much is a Megalitre, I can’t picture it? A 50m swimming pool holds 2.5ML of water.


HOW DO WE MANAGE ENVIRONMENTAL WATER?

The Upper Barwon water for the environment planning occurs in March each year in consultation with the Upper Barwon Surface Water Advisory Group (UBSWAG) and is approved by the Victorian Environmental Water Holder (VEWH).

If you are interested in joining the UBSWAG please sign up on our webpage:  Upper Barwon River - Corangamite Catchment Management Authority (ccma.vic.gov.au)

WHAT'S HAPPENING AT THE MOMENT?

The Corangamite CMA works closely with Barwon Water for the release of Environmental Flows from the West Barwon Reservoir. This water can be released down the East and or West Branch depending on the requirements for the river. As Barwon Water was undertaking some works in the East Branch (detail provided in ‘Other News - Barwon Water Update’), the CMA is focusing on sending environmental water releases down the West branch, when the reservoir is not spilling.

Environmental releases started in mid-December down the west branch, which has received 6-20ML a day since 13 December. The variability in low flows is important for hatching of invertebrate eggs, allowing native fish populations to build, and potentially reducing exotic fish populations which thrive in regulated flow regimes.

Over March 2022 we have currently reduced the flows in the west branch in preparation for in-stream works planned in this branch.


If you would like more information on Water for the Environment, please contact Hayley Vinden on Hayley.vinden@ccma.vic.gov.au or 0477 719 146

Or visit our web page : Upper Barwon River - Corangamite Catchment Management Authority (ccma.vic.gov.au)

If you are also interested in the Flow date down the Barwon River please visit: Environmental Flows - Corangamite Catchment Management Authority (ccma.vic.gov.au)

COME AND BE A CITIZEN SCIENTIST ON THE UPPER BARWON!

Upper Barwon locals are asked to become citizen scientists to monitor the condition of the Barwon River for the day or for a year.

A range of citizen science opportunities are on offer to help evaluate long term waterway improvement works. The Corangamite CMA Waterwatch program involves monthly water quality monitoring at specific sites located on the Barwon River East and West branches between Forrest and Birregurra. The monitoring data is used to help evaluate the benefits of water for the environment and on-ground riparian works.

Upper Barwon Landcare Network supported a aquatic macro-invertebrate survey of the Barwon River West Branch at Forrest in December 2021 that produced a site score of 3.7 (weighted SIGNALT score).


The Waterwatch program is supported by the Upper Barwon Landcare Network, all training is provided, no experience is necessary and the Waterwatch equipment is centrally located at Upper Barwon Landcare Network’s offices in Birregurra. Water quality testing appeals to people who want to know about the health of their local streams and can regularly do this hands-on activity.

But if time is in short supply, community members can be a citizen scientist for a day by being involved in a survey of aquatic macro-invertebrates through the National Waterbug Blitz. The survey of water bugs measures the diversity and abundance of animals and gives a score for the waterway condition. The citizen science team is using this information to help evaluate the benefits of water for the environment releases.

You can find information on upcoming National Waterbug Blitz activities scheduled for Autumn and a factsheet on Water for the Environment for the Upper Barwon River on the Corangamite CMA website.

Alternatively, you may have a special place you enjoy along the Upper Barwon River, and you might be happy to share photos that you take.

If you would like more information or would like to get involved, please contact
Deirdre Murphy, by deirdre.murphy@ccma.vic.gov.au or phone 0418 145 818 

EVENTS

A series of open house events for the Barwon Flagship are being planned for June 2022. These sessions will be an opportunity to talk with Corangamite CMA, Barwon Water, and members of the local community about the Barwon River – what you value, see as issues and possibilities.

More detail will be provided when times and dates are confirmed.

OTHER NEWS ON THE UPPER BARWON

 

SHORT TERM WORKS TO IMPROVE FLOWS


Works are being undertaken to alleviate the flood risk posed by instream infestations of Glyceria maxima on the road infrastructure.

Expert engineers completed a modelling exercise in September 2021 to determine what impact targeted removal of instream Glyceria (an invasive aquatic weed) would have on the extent of flooding. Currently Glyceria creates instream blockages to water flow that contribute to flooding. The study looked at different flow scenarios and impacts of removing the Glyceria on erosion and floodplain inundation.

In the short term, the Corangamite CMA is looking to reduce the potential for the road to flood and ensure more water can move downstream when water levels are high. Achieving this will not prevent floods from happening but would reduce the extent of localized flooding.

 


Glyceria infestation forming a dense float raft on the West Barwon River at Birregurra-Forrest Road Bridge, August 2020

The Corangamite CMA is removing 2.6 km of Glyceria on the West Barwon to alleviate flooding risks to the Birregurra-Forrest Road bridge (see image above). These works commenced in March and include revegetation of the riverbank to increase shade.
 
Mechanical removal of Glyceria is only a short-term solution. Under current conditions, even with removal of Glyceria, the weed will continue to grow instream and impede river flow. To achieve longer term river health outcomes, we need to improve flow quantity and establish riparian vegetation along significant stretches of the Upper Barwon River. Shading by native vegetation and improved flow, support the long-term control of Glyceria.