By Rose Reed May 18 2006

Little river systems can die due to the affect of damming according to Professor Jean Joss of Macquarie Univeristy following the massive fish kill at Mingo.

“It’s not surprising there’s been a fish kill, it’s totally inappropriate to have big dams on fragile little river sytems, lets hope the same mistake won’t be made on the Mary,” she said.

Her comment followed the disvcovery of 1000’s of dead fish several weeks ago by landholders in the Mingo area.

 
Drought conditions in the Burnett and an enviromental impact of Paradise Dam are believed to be responsible.

The enviromental Protection Agency has confirmed they were contacted by Sunwater several weeks ago and gave advice to them on the disposal of the dead fish.

A Sunwater spokesman said when they were informed of the fish kill they had immediatley put their Enviromental Management Plan into effect and contacted the EPA.

“We followed the directions of the EPA and travelled by boat some 17 to 20 kilometres along the Mingo area noting the dead fish and taking water samples for the EPA, we did start to clean them out but there were too many,” the spokesman said.

The EPA has not yet released the report which includes the results of the water testing and said it was liasing with Sunwater as to the cause and how a recurrence may be prevented.

However the Sunwater spokesman confirmed they had found large numbers of bony brim and landholders in the region confirmed they had found large numbers of yellow belly and catfish.

Professor Joss said she thought the fish most probably died by oxygen deprivation as rotting vegetation starved the water and the full enviromental impact of the dam may not be fully realised for up to 100 years.

“Little river systems could die-that’s what damming does, the Burnett River should never have been dammed particularly in a drought,” she said.

Gayndah biologist Graeme Armstrong confirmed that when vegetation gets submerged, bacteria eats the vegetation and in doing so uses up all the oxygen in the water.

“This leads to the death of animals, including fish, which live in the river, the process is enhanced if the temperature of the water goes up because this reduces the waters capacity to hold oxygen,” he said.

Mr Armstrong said the process was well known which was why Burnett Water Pty Ltd took vegetation out of the impounded area before the dam filled.

“However the did not take it all out. They only harvested the millable timber and left all the small trees like bottle brush,” he said.