Rivers Need Estuaries
How much do you know about the Murray Darling Basin?
The Rivers Need Estuaries campaign initiated by the Australian Environment Foundation is supported by individuals and communities throughout the MD Basin who believe:
- The health of a river system is more than the quantity of water flowing downstream;
- Current management of the terminal coastal lake system as an artificial freshwater oasis is unsustainable;
- Restoring the Murray River’s estuary must be a priority in any Murray Darling Basin Plan;
- Restoring the estuary must involve fixing the barrages which currently prevent inflows from the Southern Ocean; and
- The current focus on buying back irrigation licences, while ignoring the crippled Murray River estuary and the impact of the barrages, is misguided, unsustainable and irresponsible.
We base our assessment of the current problems in the Murray Darling, not on government reports unduly influenced by activist campaigning, but instead on peer-reviewed science and hard data.
Our logo is the mulloway fish. In 1939, millions of mulloway were trapped against the new barrage structures as they tried to make their way into the lakes to feed. More than 595 tonnes of mulloway were caught that year. Fast forward to 2008-09 and the annual catch of mulloway was only 39 tonnes. The barrages devastated the mulloway fishery and crippled the Murray River’s estuary.
Did you know that Australia’s River Murray Estuary is now only one tenth of its historic natural size?
This loss of habitat has nothing to do with ‘over-allocation’, drought, or climate change. Barrages (dams) were built in the 1940’s to keep seawater out of the Lower Lakes so local farmers could have a guaranteed year round supply of fresh water. Now 90% of this former estuary is kept completely fresh with water from the River Murray.
Retaining fresh water sounds like a good idea; what’s the problem?
During extended drought there is not enough water in upstream storages to keep the lakes with adequate fresh water. Historically, during drought seawater would hold the Lakes at sea level, never exposing acid sulphate soils to air. During the recent drought the Lakes dried out to below sea level and the barrages acted as dykes.
Why were the barrages built in the first place?
Five barrages, 7.6 km long, were built between 1933 to 1940. Like the other states, the growth of the state of South Australia depended upon a reliable source of fresh water for agriculture.
Did you know that the current ‘allocation’ and ‘entitlement’ scheme for irrigation, already takes into consideration the seasonal availability of water?
Irrigation entitlements grant the right to extract water only when when seasonal allocations are made and this depends on water availability. When water is short there are no, or very limited, allocations. During the Millennium Drought extraction entitlements were cut by over 4,000 GL by the allocation system. Buying irrigation entitlements will not put real water in the rivers and will only limit agricultural production when water is plentiful.
Did you know it makes sense to grow some crops that do not need water every year?
Australia has an extremely variable climate; some years it floods and sometimes there is drought. During the recent drought many irrigators with a water licence had no water allocation. So, for example, most rice farmers did not plant a crop.
Did you know that the barrages have decimated the mulloway fishery?
Before the barrages were built, and the Lakes changed to permanent fresh water lakes, mulloway would come through the Murray Mouth and enter the Lakes looking for food supporting a vibrant commercial fishery in the early 1900’s from Milang and Goolwa.
Barrages across a tidal estuary are just plain wrong.
If we resign ourselves to living with our past mistakes, what future do we leave our children?