Scientists are to test a number of different ways to combat algal blooms in Victorian lakes, says Dr David Fox, Manager of CSIRO's Environmental Projects Office.

Complex information about nutrients entering the water, and movement of the water within the lakes, will be used to create a powerful computer model.

This will allow researchers to assess different management options for the Gippsland Lakes.

The study will first establish a nutrient 'budget' for the lakes and then use new and existing data on water movement within the lakes to construct a three-dimensional hydrodynamic model of the system, in an effort to combat recurring outbreaks of blue-green algae.

"Couple this with an ecological model, and scientists will be able to try out different management actions, and make predictions about the likely improvement to the ecosystem."

"This is an extremely powerful tool that will enable natural resource managers to choose options for managing the Lakes and assess the response," he says.

"There have been many and varied suggestions about how the Lakes should be managed," says Dr Fox. "These range from flow control and altered catchment practices, to major engineering solutions such as dredging and physical barriers.

"Trialing these on the Lakes would be impractical, and time-consuming," he says. "By using realistic computer simulations we can look at the long-term implications of different scenarios in a matter of seconds".

Dr Fox says that CSIRO has been working with the Gippsland Coastal Board, the Victorian Department of Natural Resources and Environment, scientists and stakeholders over the past year to develop a program of research to understand the complex dynamics of the Lakes.

The Gippsland Coastal Board commissioned CSIRO to undertake an 'environmental audit' of the Lakes. "The audit suggested that high nutrient inputs from rivers flowing into the Lakes coupled with an altered saline balance was largely responsible for the algal bloom outbreaks," the Board's Chairman, Mr Duncan Malcolm says.

"In March last year the Lakes suffered a particularly severe and widespread toxic blue-green algal bloom that restricted the use of the Lakes over a 12-week period, which resulted in the first ever restrictions on the consumption of fish caught in the Lakes."

Mr Malcolm says "It has been estimated to have cost the local fishing industry $1.6M in lost production, and that the local tourist industry also suffered an estimated 30% decline during the period of the bloom."

The new $600,000, 18 month study is a joint project between CSIRO and the Victorian Department of Natural Resources and the Environment, involving scientists from CSIRO, University of Melbourne, Environment Protection Authority, and Victoria's Marine and Freshwater Resources Institute.

More information from:
Dr David Fox, CSIRO Environmental Projects Office 0417 937 624
(from Friday evening) 08 9333 6758
Mr. Murray Rankin, Gippsland Coastal Board 03 5153 0456
0419 320 423
Ms Margaret Bryant, CSIRO Land & Water 08 9333 6215

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