Did you know it’s been 10 years of continuous flows through the barrages from South Australia’s River Murray to the Coorong following the devastating Millennium Drought?
While the drought was a terrible time, thanks to the hard work and strong collaboration between governments, the local community and environmental scientists, improvements have been observed in the local ecology and community.
And many of these improvements have been made possible by the delivery of water for the environment flowing down the river.
What impact did the drought have?
The entire Murray-Darling Basin experienced an extended period of drought, with the worst conditions for the South Australian end of the system occurring in 2007-2010.
Water levels in the Lower Lakes and weir pool below Lock 1 dropped to a metre below sea level, resulting in no flow through the barrages to the Coorong estuary for more than three years.
This meant the ecology of the region suffered considerably, creating issues like escalating salinity, no migration opportunities for native fish, little to no food resources for migratory birds and other waterbirds, and a depletion of invertebrate and plant species in the area.
The good news is the natural environment has been recovering slowly with the help of supplementary water for the environment for specific ecological outcomes.
While we have had some periods of good flows, much of the site, particularly the Coorong, is still in a period of recovery and there is still lots of work to be done.
How have continuous flows helped?
There are many good stories as a result of the last 10 years of connectivity, both for the environment and for the people who rely on it, including the commercial fishing and tourism industries.
Diadromous fish are now migrating between fresh and salt water in increasing numbers, some migratory shorebirds are returning in reasonable numbers, salt export is helping to maintain riverine salinity levels and native fish populations continue to increase in the Lower Lakes.
Specifically, research shows the delivery of water for the environment has helped achieve the following outcomes:
- Barrage fishways have been continuously open and operating since September 2010.
- A recovery from near local extinction of the native fish congolli.
- A significant recruitment event for the Coorong black bream population in 2017/18.
- Increased detection of pouched and short-headed lamprey undertaking winter migration.
- An increase in abundance and diversity of invertebrates in the Coorong North Lagoon.
- A steady increase in diversity and extent of aquatic plants in the Lower Lakes.
- Improvements in recruitment of Murray hardyhead fish in the Lower Lakes.
More than 12 years of data collection through The Living Murray program has also helped increase water managers’ understanding of how the Coorong, Lower Lakes and Murray Mouth system responds to flows.
They now have a greater ability to fine-tune the timing, location, duration and extent of flows to target certain species and outcomes – allowing more efficient use of water for the environment.
Commemorating 10 years of connectivity
The community came together to celebrate the ecological, social, economic and cultural recovery that is occurring at this iconic wetland and acknowledge the continuing importance of water for the environment in keeping the area and its communities alive.
The gathering, however, was about more than just connection in the waterways, it’s also about connection between people. Ten years of continuous connectivity honours all those who have worked tirelessly together for the area’s recovery.
Learn more about this species that call the River Murray home – like the toothy, eel-like lamprey. Here’sits story.