The Environment Protection Authority (EPA) and the Department of Industries and Regional Development (DPIRD) are working with local councils to respond to the fish kills in Richmond and Clarence waterways after ex-cyclone Alfred.

The fish deaths are the result of a series of Hypoxic water events which occur when floodplain vegetation dies and organic material is washed into waterways during flooding.

As this organic material breaks down in the water, it depletes the levels of dissolved oxygen. Without sufficient levels of dissolved oxygen, fish and other aquatic organisms struggle to breathe, and in some cases, this causes them to die.

Water can appear dark brown or black as the organic matter decays due to the release of dissolved carbon compounds, including tannins.

The EPA and DPIRD are working with local councils to manage clean-up actions in key locations where fish deaths have been reported.

As part of flood debris clean-up in waterways, the EPA has engaged specialist clean-up contractors who are collecting dead fish from accessible riverbanks during their search for large and hazardous flood debris.

Last week clean-up contractors were working in the Tweed, Clarence and Manning Rivers. This week, clean-up contractors will start work in the Richmond River.

Community members are encouraged to report any fish deaths or water quality concerns to the Fishers Watch on 1800 043 536. 

Read more: It’s eerie, a river with no life left in it – More fish kills in Richmond and Clarence rivers
This information was provided by the EPA.

This article appeared on indyNR.com on 29 March 2025.
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