WHERE HAS THE MURRAY DARLING BASIN'S WATER GONE?

**bob10** · 24th September 2020, 07:23 AM

Originally Posted by ramblingboy42

Cubby harvests floodwater , doesn't pump out of the Darling or it's tributaries.

Yes, but it's that floodwater that has flushed out and regenerated the Murray / Darling eco system for thousands of years. Yes it's legal , but no thought was given to the cumulative effect over time of the lack of refreshing flood water for the ephemeral watercourses of the Murray/ Darling. Many rivers and creeks of the system only flow during flood , the rest of the time are just a string of pools along the water course. By taking the flood water from the Culgoa catchment , in time of flood, Cubby has unwittingly denied those regenerative flood waters from flowing into the wider Murray/ Darling system.

It's this water flow that helps flush the river of salt, sediment and nutrients. High water flows are the way floodplains and wetlands receive sediment and nutrients, and how ground water systems are recharged. By artificially changing the eco-system, as in Cubby Station cotton growing, denying the wider system of these flood waters, Europeans have unknowingly committed the Murray Darling to a slow death. The corrupt mismanagement of the system by modern Australians hasn't helped, but is just one part of the problem .

Perhaps the definition of floodplains and wetlands would be helpful to understanding the wider implications of the European folly of trying to artificially change nature, with no thought for the long term consequences.

Floodplains

A floodplain is the land alongside a river that is slightly higher in elevation, and, as the word suggests, becomes flooded when there are high volumes of water in the river system. The plain itself is mainly made up of sediment that has been deposited by the existing river in times of flood, or sometimes by ancient rivers that flowed through the general area of the floodplain. Some floodplains have a more complex geology, influenced by previous high sea levels or earth movements at a local scale that lifted or created specific soil and rock formations.
The areas of the floodplain that remain wet after flood waters recede are called wetlands.
Floodplains are an important feature of the Basin. They contain unique ecosystems, such as the Barmah–Millewa Forest in the central Murray catchment, and they provide fertile ground for irrigated agriculture, such as the area alongside the Darling River from Bourke to Menindee. Below the surface of the floodplain there is usually a complex system of underground streams and aquifers that are connected to the river. The quality of the groundwater beneath floodplains is highly variable, and can also be influenced by the groundwater that flows from upper catchment areas.
Floodplain vegetation is important as it uses groundwater in the soil profile. This prevents water and salts rising to the surface or being transported to the river. Irrigation can increase the height of the watertable, dissolving salt in the soil and bringing salt into the root zone of crops or into aquifers that flow into the river.
Flooding is the natural process by which excess salts are periodically removed from the floodplain and the river system.
Wetlands

Wetlands are areas on the floodplain that are at times inundated with shallow, still (or slow moving) water. They are among the Basin's most productive and biologically diverse ecosystems, providing essential breeding and feeding habitat for many kinds of organisms─ waterbirds, fish, invertebrates, and plants. Wetlands are also important in absorbing, recycling and releasing nutrients and trapping sediment, acting as natural filters which improve water quality. At the same time, excessive pollutants will degrade or destroy wetlands. Wetlands also increase the productivity of associated aquatic and terrestrial ecosystems
Wetlands add to the diversity of the landscape and are the focus for a number of recreational activities. Given the Basin's generally dry but highly variable climate, the wetlands act as environmental buffer areas. During wet periods, they spread flood peaks and store floodwaters, releasing them gradually and reducing the effects of flooding. During drought, they provide refuges for wildlife and grazing for stock.
The Basin has over 30,000 wetlands, some of them listed internationally (Australia's Ramsar wetlands) for their importance to migratory birds that visit the site. To be healthy and promote life, the wetlands of the Basin need to be alternately wet and dry.

**bob10** · 24th September 2020, 07:49 AM

Flow-MER, heard of it ? If you scroll down, there is an excellent map of the whole Murray / Darling system, showing how each small section is part of the whole , and how a change in one place will flow on [ no pun intended] to another.

"The Flow-MER program team acknowledge and respect the Traditional Owners as the First Peoples of the lands and waters of the Murray Darling Basin.

We recognise their unique ability to care for Country and their deep spiritual connection to it. We honour Elders past and present whose knowledge and wisdom has ensured the continuation of culture and traditional practices.

We are committed to genuinely partner, and meaningfully engage, with Traditional Owners and Aboriginal communities to support the protection of Country, the maintenance of spiritual and cultural practices and their broader aspirations in the 21st century and beyond. In particular we acknowledge the Traditional Owners of the seven Selected Areas where Flow-MER research is focussed."

Flow '-' Monitoring, Evaluation and Research program

**Tote** · 24th September 2020, 07:54 AM

The Murray darling is beset by the competing demands of irrigators who have all been granted licences to remove water from the river by their respective state governments. The state governments have proven recently that they are incapable of working together to achieve a collaborative outcome.

Cubby is only pumping what it is allowed to, along with most other irrigators on the river. If Cubby is harvesting floodwater where would that floodwater go if not captured? However Cubby isnt the problem, the over allocation of irrigation licenses is.

How do you wind back a scheme where state governments have issued licenses for more water that they have and where resuming those licenses would impact on industries and towns along the river. It's easy to make statements such as just shut (insert irrigator here) down, however that irrigator is operating under a legally issued licence from their respective government.

There is also the perspective of the "environmentalists" who want regular flows at any cost and will not accept that in a river system that naturally fluctuates between 0 and 12 metre river heights there will be events like fish kills.

The Murray Darling Basin Authority is probably a good start but they only have oversight of state resources and no control over flood flows that are not controlled by dams.

Regards,
Tote

**bob10** · 24th September 2020, 08:41 AM

Originally Posted by Tote

If Cubby is harvesting floodwater where would that floodwater go if not captured? However Cubby isnt the problem, the over allocation of irrigation licenses is.

Regards,
Tote

It's myopic reasoning that has perpetuated the problem, by focusing on part of the problem, not the whole. Cubby is part of the problem, as is irrigation. Too much irrigation increases the height of the water table dissolving salt into the soil and bringing salt into the root zone of crops or into aquifers that flow into the river. Flooding is the natural process by which excess salts are periodically removed from the floodplain and the river system.

In Australia primary responsibility for managing wetlands and their associated flora and fauna is invested in the appropriate land holders/ land managers. Individual State And Territory Governments have the primary legislative and policy responsibility for natural resource management. The Australian Government Department of the Environment is the administrative authority within Australia for the RAMSAR Convention on Wetlands of International importance.

The Australian Government meets its obligations under the RAMSAR convention by providing National wetland policy leadership and direction , working with State and Territory governments through the Standing Council on Environment and Water, implementation of the Environment Protection and Bio- diversity Conservation Act 1999 ,and by the development of programs to improve the development of wetlands.

**bob10** · 24th September 2020, 08:46 AM

Originally Posted by ramblingboy42

the Darling is my river , I spent a lot of my youth on and around it.....it makes me cry to see one of the oldest worlds eco systems abused like this.

You might appreciate this. Part of my bucket list is a drive down along the Warrego/Darling.

Selected Area: Warrego'-'Darling | Flow'-'MER Program

**bob10** · 24th September 2020, 08:53 AM

Originally Posted by Tote

The Murray Darling Basin Authority is probably a good start but they only have oversight of state resources and no control over flood flows that are not controlled by dams.

Regards,
Tote

The Murray Darling Basin Authority. The Murray–Darling Basin Authority operates the River Murray on behalf of New South Wales, Victoria and South Australia.

Murray-Darling Basin Authority |

**bob10** · 24th September 2020, 08:55 AM

River Murray water allocations, THE FACTS.

River Murray water allocations | Murray-Darling Basin Authority

A video on water allocations.

River Murray water allocations on Vimeo

**Tote** · 24th September 2020, 11:39 AM

From the link you posted:

Each state has their own unique suite of water entitlement products. For example New South Wales has high security and general security licences. In Victoria, there are high and low reliability water shares. South Australia has something different too. These products are different and not comparable.
Also contributing to the differences between water products in the River Murray system are state shares. Where rainfall occurs in each catchment drives differences in state shares and how much water a state has to allocate.
For more information on your state allocation approaches, contact your state water department.

That sums up the difficult bit, also MDBA only has control of water releases from dams, the dams that contribute to the available flows in the upper darling are negligable in comparison to the catchment area and no one controls the amount (or lack of) flood water, however different states have different schemes as mentioned above on what can be done with that floodwater.

A good contrast is the snowy river where environmental flows are reasonably easy to manage, there is a big dam at the top and it is only a matter of freeing up enough water allocation to increase the flows. It is much more difficult on the Darling.

Regards,
Tote

**bob10** · 24th September 2020, 11:48 AM

For those interested, how the States operate.

**bob10** · 24th September 2020, 11:52 AM

Flood plain harvesting in NSW. Flood plain harvesting is the last substantial capture of water to be licenced in the basin which will improve accounting and compliance of water use in NSW.

Floodplain harvesting program - Water in New South Wales

Thread: WHERE HAS THE MURRAY DARLING BASIN'S WATER GONE?

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