Why isn an embankment in Lake Alexandrina constructed, creating a salt water lake within the fresh water lake?
The former Murray-Darling Basin Commission considered a range of options for saving water in the Lower Lakes. These included building an embankment, or ‘bund’, within Lake Alexandrina to form a salt water lake inside the fresh water lake. This would be a very expensive technical engineering solution. Construction costs and environmental impacts were considered too high for it to be carried out. Other issues included increased salinity in the inner marine lake, which could lead to hyper-saline conditions, and impact on estuarine plants and animals. There are also issues about whether the structure could physically be built on top of the soft sediments of Lake Alexandrina to withstand wind and tide movements. Building a permanent inner salt water lake within the fresh water lake would have a permanent, negative effect on the Lower Lakes and Coorong’s environment and permanently impact on recreational boating. Although the current low river flows are placing pressure on the river system,
