Cohuna and Koondrook Fishways Project

From March to October 2021, GMW will be working with the North Central Catchment Management Authority (CMA) to construct two fishways along the Gunbower Creek, at Cohuna and Koondrook, as part of the North Central CMA’s Native Fish Recovery Plan.

The construction of the fishways is the last piece in the puzzle to enable fish, including the iconic Murray cod, to safely move between the creek and the Murray River.

The fishways will benefit the local community through increased recreational fishing and ecotourism opportunities, which contributes more than $304M a year to the regional economy.

There has never been a more important time to invest in the Cohuna and Koondrook communities and help their small businesses get back on their feet. The project will create jobs for local people in the area, bringing much-needed economic benefits.

The Native Fish Recovery Plan

The Native Fish Recovery Plan - Gunbower and lower Loddon aims to create a world class fishery in northern Victoria and recover threatened species by addressing flows, habitat and connectivity for native fish.

The Plan provides a unique opportunity within the Torrumbarry Irrigation Area to assist recovery of native fish populations and demonstrate how the irrigation industry and the environment industry can work together.

To read more about the Plan, please visit the NCCMA website.

Cohuna Weir Fishway Works

Cohuna Weir

Re-built in 2005, the Cohuna Weir on Gunbower Creek is one of the last barriers to upstream fish passage along Gunbower Creek (the other being Koondrook Weir).

Once constructed, Cohuna fishway will allow safe passage for iconic fish species including the golden perch, threatened silver perch and Murray cod upstream and downstream of the existing weirs and importantly access to critical breeding habitat throughout the entire Gunbower Creek.

The Cohuna fishway is fully funded by GMW and will comprise of a 23-slot vertical slot fishway attached to the existing Cohuna Weir. Improvements in public access and fencing for safety will also be completed to further enhance and complement the recent Gannawarra Shire Cohuna CBD waterfront development.

Koondrook Weir Fishways Works

Koondrook Weir

Along with Cohuna Weir, Koondrook Weir is one of the last barriers to upstream fish passage along the Gunbower Creek. Near the junction of Gunbower Creek and the Murray River, the weir currently blocks fish movement between the two systems.

When high flows are passed over Koondrook Weir, large numbers of native fish such as golden perch congregate, seeking to access the high-quality habitat in Gunbower Creek.

The fishway will provide passage to native fish such as golden perch and the vulnerable Murray cod from the river into the creek for the first time in more than a century.

The Koondrook Weir fishway is co-funded by the Victorian Environmental Water Holder and the Victorian Government, and is part funded from the sale of water for the environment to irrigators. It will comprise of a double-entrance and double exit vertical slot fishway, with sheet pile walls to create a stilling pool to dissipate energy. The undershot gates will be replaced with overshot gates to allow for improved flow conditions and safe downstream fish passage.

Construction

Construction of both fishways is planned for March to October 2021:

  • Out of creek construction works will commence first (March to 15 May) and will not interrupt irrigation supply.
  • The majority of works will be done during the irrigation season shutdown from 15 May to 15 August 2021.
  • The works will require a one-off drawdown of the weir pool during the irrigation season shutdown period. 

Customers who rely on Domestic and Stock supply are reminded to fill their domestic and stock dam ahead of the irrigation season shutdown period – beginning 15 May. 

(During the irrigation off season, GMW cannot guarantee access to water from the channel network for Domestic and Stock purposes due to channel maintenance and works requirements.)

Community impacts

Both fishways have been designed to have minimal impacts on the residents of Cohuna and Koondrook.

In Cohuna, the walking access track over the Cohuna Weir structure will be closed for the duration of the works, however the Cohuna Public Recreation Reserve, including the swimming pool will remain accessible via Cohuna Island Road.

Recognising the importance of the large foreshore trees in Cohuna and their location to the planned works site, GMW has conducted detailed vegetation assessments to assist in minimising any vegetation/tree removal impacts. 

In Koondrook, there will be some access track/road closures throughout Gunbower Forest during the Koondrook Fishway construction period. Alternate routes will be available and signposted.

During construction there may be aesthetic and potential noise impacts for the community as a whole. Where possible these will be kept to a minimum.

For more information

Environmental enquiries - North Central Catchment Management Authority via email at info@nccma.vic.gov.au  

Construction enquiries – GMW Project Manager Linc Wellington via email at info@gmwater.com.au or on 1800 013 357.