Gippsland Lakes

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Landsat 7 imagery of the Gippsland Lakes. Lakes Entrance is visible in the top right of the image.

The Entrance to Gippsland Lakes

Lake King from Shaving Point in Metung

The Gippsland Lakes are a network of lakes, marshes and lagoons in east Gippsland, Victoria, Australia covering an area of about 600 km sq, The largest of the lakes are Lake Wellington (Gunai language: Murla^[1]), Lake King and Lake Victoria. They are fed by the Avon, Thomson, Latrobe, Mitchell, Nicholson and Tambo rivers.

The lakes were formed by two principal processes. The first is river delta alluvial deposition of sediment brought in by the rivers which flow into the lakes. Silt deposited by this process forms into long jettys which can run many kilometres into a lake, as exemplified by the Mitchell River silt jetties that run into Lake King. The second process is the action of sea current in Bass Strait which created the Ninety Mile Beach and cut off the river deltas from the sea.

Once the lakes were closed off a new cycle started, whereby the water level of the lakes would gradually rise until the waters broke through the barrier beach and the level would drop down until it equalised with sea-level. Eventually the beach would close-off the lakes and the cycle would begin anew. Sometimes it would take many years before a new channel to the sea was formed and not necessarily in the same place as the last one.

In 1890 a wall was built to fix the position of a naturally occurring channel between the lakes and the ocean at Lakes Entrance, to stabilise the water level, create a harbour for fishing boats and open up the lakes to shipping. This entrance needs to be dredged regularly, or the same process that created the Gippsland Lakes would render the entrance too shallow for seagoing vessels to pass through.

The lakes support numerous species of wildlife and there exist two protected areas within: The Lakes National Park and Gippsland Lakes Coastal Park. The Gippsland Lakes wetlands are protected by the international Ramsar Convention on wetlands. The wetlands provide habitat for about 20,000 waterbirds – including birds from as far afield as Siberia and the North Pole. There are also approximately 400 indigenous flora species and 300 native fauna species. Three plants, two of them being orchid species, and two bird species, the Regent Honeyeater and Swift Parrot, are listed as endangered.