Goulburn-Murray Water (GMW) will begin early works on the Koondrook and Cohuna Weir fishways in coming weeks with preliminary inspections and investigations set to take place at the two Gunbower Creek sites.
The fishways will enable upstream and downstream passage of native fish by connecting the length of Gunbower Creek between Koondrook Weir and the National Channel Inlet Regulator.
In the coming weeks, GMW staff will inspect the sites to assess cultural and environmental impacts of the works while practising physical distancing. A contract will be awarded in late December 2020 with tender documents being issued in September in readiness to undertake these major projects in 2021.
Building of the Koondrook and Cohuna fishways is planned for February to October 2021, with the majority of works being undertaken during the irrigation season shutdown from May 15 to August 15, 2021. The works will result in a drawdown of the weir pool during the shutdown period and GMW will aim to minimise the aesthetic impact on the local community.
Quotes from GMW General Manager Infrastructure Delivery Services Warren Jose
“The Cohuna and Koondrook fishways will enable upstream and downstream passage of native fish, connecting the length of Gunbower Creek between Koondrook Weir and the National Channel Inlet Regulator.”
“The unique design of these vertical slot fishways provides passage for a wide range of species, large and small, to ensure broad benefits to fish populations including the Murray cod.”
“It is exciting to be one step closer to launching this project, alongside our partners at the North Central Catchment Management Authority, Department of Land, Water and Planning and Victorian Environmental Water Holder.”
“The project will create jobs for local people in the area bringing much needed economic benefits.”
Quotes from North Central Catchment Management Authority Environmental Projects Assets Manager Nicole Bullen.
“Fish need to be able to swim upstream to survive and thrive, and with weirs in the way they can’t.”
“These projects are great news if you love fish. Once all barriers to fish movement are removed, the threatened Murray cod and golden perch and critically endangered silver perch will have almost 700kms of waterways to breed and feed in.”
“Gunbower Creek is ideal habitat for perch and cod, and this work complements the current environmental flows program in the creek.”
“We want to create a world-class native fishery in the rivers and creeks around Cohuna, and these projects are a big step towards that.”
Quotes from Gannawarra Shire Council Chief Executive Officer Tom O’Reilly
“Once completed, the fishways at Cohuna and Koondrook will provide environmental benefits to local wildlife, which, in turn, will be beneficial to our growing nature based tourism sector.”
Background:
The Koondrook Weir fishway is co-funded by the Victorian Environmental Water Holder and the Victorian Government and will comprise:
- A double-entrance, 25 slot vertical fishway;
- Sheet pile walls to create a stilling pool to dissipate energy;
- Replacement of the undershot gates at the existing weir and installation of FlumeGates™ allowing improved flow conditions for the effective operation of the fishway.
The Cohuna Weir fishway is funded by GMW and will comprise:
- A vertical slot fishway attached to the existing Cohuna Weir
- Improvements in public access and fencing for safety
Koondrook Weir is the last weir on Gunbower Creek, about six kilometres upstream from the creek’s confluence with the Murray River. The weir maintains a stable pool level to provide water to the No. 4 and No. 5 channels during the irrigation season. Cohuna Weir was re-built in 2005. Both weirs are a barrier to upstream fish passage along Gunbower Creek.
Upstream, vertical slot fishways have been built at Gunbower Weir and Hipwell Road Weir, and a rock ramp fishway at Thompsons Weir. Gunbower Creek is an important economic and environmental asset to the region, providing a range of values to Gunbower, Cohuna, Leitchville and Koondrook communities.
The creek is part of the Torrumbarry Irrigation Area and is primarily operated as an irrigation channel to deliver water for domestic and agricultural use. Water from the Murray River is diverted into Gunbower Creek via the National Channel above Torrumbarry Weir and is controlled by a series of weirs and regulators. Gunbower, Thompsons, Cohuna and Koondrook weir pools control water that is extracted by direct diverters as well as delivered throughout the irrigation district via the No.3, No.4 and No.5 channels.
Gunbower Creek runs parallel to the Murray River creating a forested island floodplain of up to eight kilometres wide. The floodplain is a Living Murray Icon Site, of which Gunbower Creek forms the southern boundary.