Pump up the volume

Photos: Aerial: Michael Bell, Pelican: Richard Brown.

The volume of water that is! Pumps have started moving water from Lake Alexandrina to the Lower Lakes to prevent them from becoming acidic. On 2 May, water began flowing into Lake Albert, which is hoped will reduce the risk of environmental damage.

The reduced availability of water to the lower end of the Murray-Darling system has led to some serious health issues. The extremely low water levels mean that there is a very high risk of irreversible damage from exposure of acid sulphate soils.

Acid sulphate soils contain sulphuric acid, or can form sulphuric acid when exposed to oxygen in the air — such as when a lake bed usually covered by water is exposed to the air. This can lead to low water quality that may harm wildlife and threaten public health.

The Minister for Climate Change and Water and Chair of the Murray-Darling Basin Ministerial Council, Senator Penny Wong, and the South Australian Minister for the River Murray, Karlene Maywald, said the pumping would be undertaken by South Australian Government agencies for the Murray-Darling Basin Commission (MDBC).

The Lake Albert pumping project is a temporary measure that will prevent the lake from acidifying. The ultimate solution is to allow more water to flow down to the end of the system to improve the health of the Lower Lakes and Coorong.

“The Coorong and Lakes Alexandrina and Albert wetlands are among our best-known wetland systems and an icon site under The Living Murray initiative. Their importance is recognised internationally,” Senator Wong said.

The Coorong, Lower Lakes and Murray Mouth are internationally recognised Ramsar-listed sites (under the Ramsar Convention) being part of an agreement regarding environmental conditions for migratory birds. The Murray-Darling Basin Ministerial Council has recognised that the crisis facing the Lower Lakes is a national issue and that all areas within the Basin must be part of the solution.

The water provided from Lake Alexandrina is expected to have a minimal impact on that lake but is expected to safeguard Lake Albert until later this year.

Extensive monitoring will be undertaken to evaluate the effects of the pumping on Lake Albert. In coming days, a silt plume may be visible in the channel connecting Lake Albert and Lake Alexandrina due to the large volume of water being transferred.

Depending on how the lakes respond to the additional water, the MDBC will look at options for the medium to long-term management of the Lower Lakes at its October 2008 meeting.

For more information go to www.environment.gov.au/minister/wong/2008/index.html