Victoria's Gippsland Lakes are the latest battleground in the national struggle to turn the tide on the toxic blue-green algal plague afflicting Australia's lakes, rivers, estuaries and coastal lagoons.

Research into the causes of algal blooms and ecosystem decline in Gippsland Lakes is paving the way for better management of many of Australia's most important and beloved waterways, says CSIRO Land & Water Chief, Dr Graham Harris.

A combination of land clearing, damming of rivers, declining rainfall, nutrient inflows, overfishing, carp and salinity have led to a situation where the Lakes can "turn green virtually overnight", Dr Harris told a National Science Briefing in Sale, Victoria, hosted by Federal Minister and local MP Peter McGauran.

"The risk of such devastating algal blooms can be reduced – but our efforts need to be focussed in order to achieve greater value from limited resources," he says.

Researchers from CSIRO, the Marine and Freshwater Research Institute and Victorian Environment Protection Authority have accumulated wide knowledge about the water, sediments, marine life, climate and human impacts to explain how the Lakes function.

"We can now take physical data like weather conditions and water inflows to model water circulation. Combine this with our understanding of nutrient cycling and you can model the entire ecosystem," says Dr Harris.

"From this you can predict whether it will lead to the growth of algal blooms – or to healthy meadows of seagrass which support fish, prawns and other marine life."

These models can then be used to test various strategies for curbing toxic blue-green algae, to see whether they work or not, Dr Harris says.

"We can then answer questions like: how much must we cut nutrient levels in the Lakes to reduce algal blooms? How long will it take for the accumulated nutrients in the Lakes to dwindle so they no longer support blooms? What will happen if we flush the Lake system with sea water?"

The Chairman of the Gippsland Coastal Board, Mr Duncan Malcolm, said CSIRO had sounded a warning that the Lakes were approaching a crisis point during an environmental audit for the Board's Coastal Action Plan.

There remained some concern that the many activities being undertaken throughout the Lakes catchment by local authorities and communities might not bring about an improvement quickly enough.

"CSIRO have recommended a hydrodynamic model to better understand catchment and in-lake processes and to test engineering, technological and hydraulic options to improve water quality.

"The Gippsland Coastal Board has asked that the modelling be carried out under the direction of CSIRO, with the support of regional stakeholder groups.

"The development of the model means the Board and regional stakeholders are covering all possible avenues for providing long-term protection of the Gippsland Lakes," Mr Malcolm said.

More information:
Dr Graham Harris, CSIRO Land & Water Mobile:0417 463 158
Mr Duncan Malcolm, Gippsland Coastal Board Mobile: 015 812 367
Mr Murray Rankin, Gippsland Coastal Board Ph:03 51 530 456
Dr David Fox: Environmental Project Office Mobile:0417 937 624
Mr Robert Molloy, Environmental Project Office Mobile 0408 572 241
Ms Margaret Bryant, CSIRO Land & Water 08 9333 6215 or 0417 247 241