Gippsland Lakes salinity concerns


I HAVE watched the Gippsland Lakes salinity debate ebb and flow for some time now.

This debate has been ensuing largely in the absence of any publicly available real time monitoring data related to salinity penetration within the Lakes.

Questions should be asked as to why this is the case, after millions of dollars per year are spent on management of the Lakes and catchment.

The Gippsland Lakes are actually not real lakes they are in fact a large coastal lagoon system.

Prior to the opening of the artificial entrance at Lakes Entrance, the Lakes contained mainly fresh water.

The natural entrance opened and closed, and migrated along the Ninety Mile Beach, according to the competition between coastal processes (trying to close the entrance with sand), and fresh water inflows to the Lakes (trying to break out to sea).

Due to these natural processes (and others interacting dynamically with them), at times the water would be more brackish within sections of the Lakes than fresh, and vice versa.

All that changed with the opening of the artificial entrance in 1889.

The Lakes as an ecosystem has never been the same since.

Current entrance dredging processes are quite effective in their job.

The channels are now maintained at a depth that is deeper overall than has been sustained since soon after the entrance was opened to the sea.

While this is certainly a boon to entrance users, the increased channel dimensions have allowed more salt water to enter the lakes on each tidal cycle.

It is therefore not surprising, for example, that locals throughout the system have noted the incidence of invasive marine species far into the lakes system.

These results should in fact be an expected byproduct of a deeper entrance.

Perhaps some of the initial 30 million dollars provided by the Victorian ALP Government in 2005 to fund the Lakes Entrance Sand Management Program should have been used to research likely environmental impacts on the lakes produced by a deeper entrance and channel system.