It’s official: expert review rejects NSW plan to let seawater flow into the Murray River

Jamie Pittock, Australian National University; Bruce Thom, University of Sydney; Celine Steinfeld; Eytan Rocheta, UNSW, and Nicholas Harvey, University of Adelaide

A major independent review has confirmed freshwater flows are vital to maintaining the health of the Murray River’s lower lakes, striking a blow to demands by New South Wales that seawater flow in.

The review, released today, was led by the CSIRO and commissioned by the Murray Darling Basin Authority. It examined hundreds of scientific studies into the lower lakes region of South Australia, through which the Murray River flows before reaching the ocean.

The review recommends managing the lakes with freshwater, not seawater. More importantly, it highlights how climate change and upstream farming is reducing the flow of water for the environment in the lower lakes.

These findings are critically important. They show the severe health threat still facing the river system and its internationally important wetlands. They also cast doubt on whether the A$13 billion basin plan can achieve all its aims.

A plan to save the parched Murray Darling system may not succeed.
Dean Lewins/AAP

A barrage of criticism

The Murray Darling river system runs from Queensland, through NSW, the ACT and Victoria. In South Australia the River Murray discharges into two large lakes, Alexandrina and Albert, before flowing into the 130 kilometre-long Coorong lagoon, through the Murray Mouth and into the ocean.

Since 1940 five low dams, or barrages, have stopped seawater flowing into the lakes from the Murray Mouth and Coorong, and raised the lakes’ water level.

NSW wants the barrages lifted to allow seawater back into Lake Alexandrina, to free up freshwater for agriculture upstream.

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In December 2019, NSW Nationals John Barilaro said: “I refuse to let regional communities die while we wash productive water into the Great Australian Bite (sic), 1000km away”. Irrigation advocates have backed his calls.

Victoria has also questioned whether the lower lakes can continue to be kept fresh, given the water scarcity plaguing the entire river system.

But today’s review confirmed the lower lakes were largely a freshwater ecosystem prior to European occupation. It said removing the barrages would cause significant ecological and socioeconomic harm, and would not lead to water savings if the basin plan targets are to be met.

The Murray Mouth is choking

The review cited research we published this month, which concluded it was impossible to achieve the basin plan target to keep the Murray Mouth open 95% of the time.

This is because Murray Darling Basin Authority modelling did not factor in the power of the Southern Ocean to move sand into the Murray Mouth, which is now choked. Dredging will be required most of the time to keep the Murray Mouth open and maintain the ecology of the Coorong.

The Coorong and Lakes Alexandrina and Albert are a wetland of international importance under the Ramsar Convention.

The review found removing the barrages would significantly change the freshwater character of the site, which we have an international obligation to maintain for the sake of waterbirds, fisheries and threatened species.

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This is becoming harder during periods when freshwater inflows are scarce. In the Millennium Drought for example, lake levels fell exposing highly acidic mudflats. In other areas, the waters became more salty.

After the basin plan was adopted in 2012, the condition of the lower lakes improved when the Millennium Drought broke and environmental flows were delivered, sustaining the system in the current drought. But very little of those flows enter the sea, except during floods.

The system of barrages in the lower lakes consist of 593 gates. Using official data, we calculate that for 70% of the time since 2007, fewer than ten gates have been open to the sea. For one-third of the time, none were open, indicating there is insufficient water to sustain fisheries and flush salt to the ocean.

Our research concludes that without the barrages the sand banks will reduce the volume of water flowing through the Murray Mouth. The tides would not be strong enough to keep the lakes flushed so water quality would decline. No barrages means lower lake levels and exposed mudflats, generating sulphuric acid.

Aerial view of the Murray River barrages, circa 1940.
State Library of South Australia

An uncertain future

The review reinforces the South Australian government’s position that the lakes should be maintained with freshwater. It also obliges the federal government to implement the basin plan in its current form, despite NSW’s demands for changes.

The final report also highlighted how climate change will make management of the Coorong, Lower Lakes and Murray Mouth “increasingly challenging” and said adaptation options were needed for the entire river system.

By the end of this century, rising seas may flow over the barrages. Maintaining freshwater inflows and the barrages buys us time, but we need a serious national conversation about how to manage this challenge.

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The federal and South Australian governments recently announced a Coorong Partnership to enable local communities and groups participate in programs to improve management of the lagoon. This is timely and should be expanded to cover the broader Lower Lakes and Murray Mouth regions.

Freshwater flowing from the headwaters to the sea is vital for the health of the Murray-Darling Basin as a whole. Today’s report should be the start of the national discussion on shoring up the health of Australia’s most important river system in the face of an uncertain future.

Jamie Pittock, Professor, Fenner School of Environment & Society, Australian National University; Bruce Thom, Emeritus Professor, University of Sydney; Celine Steinfeld, Acting Director, Wentworth Group of Concerned Scientists & Adjunct Lecturer at UNSW Sydney; Eytan Rocheta, Policy Analyst, Wentworth Group of Concerned Scientists & Adjunct Associate Lecturer at UNSW Sydney, UNSW, and Nicholas Harvey, , University of Adelaide

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Is the Murray-Darling Basin Plan broken?

Ross M Thompson, University of Canberra

A recent expose by the ABC’s Four Corners has alleged significant illegal extraction of water from the Barwon-Darling river system, one of the major tributaries of the Murray River. The revelations have triggered widespread condemnation of irrigators, the New South Wales government and its officials, the Murray-Darling Basin Authority and the Basin Plan itself.

If the allegations are true that billions of litres of water worth millions of dollars were illegally extracted, this would represent one of the largest thefts in Australian history. It would have social and economic consequences for communities along the entire length of the Murray-Darling river system, and for the river itself, after years of trying to restore its health.

Water is big business, big politics and a big player in our environment. Taxpayers have spent A$13 billion on water reform in the Murray-Darling Basin in the past decade, hundreds of millions of which have gone directly to state governments. Governments have an obligation to ensure that this money is well spent.

The revelations cast doubt on the states’ willingness to do this, and even on their commitment to the entire Murray-Darling Basin Plan. This commitment needs to be reaffirmed urgently.

Basic principles

To work out where to go from here, it helps to understand the principles on which the Basin Plan was conceived. At its foundation, Australian water reform is based on four pillars.

1. Environmental water and fair consumption

The initial driver of water reform in the late 1990s was a widespread recognition that too much water had been allocated from the Murray-Darling system, and that it had suffered ecological damage as a result.

State and Commonwealth governments made a bipartisan commitment to reset the balance between water consumption and environmental water, to help restore the basin’s health and also to ensure that water-dependent industries and communities can be strong and sustainable.

Key to this was the idea that water users along the river would have fair access to water. Upstream users could not take water to the detriment of people downstream. The Four Corners investigation casts doubt on the NSW’s commitment to this principle.

2. Water markets and buybacks

The creation of a water market under the Basin Plan had two purposes: to allow water to be purchased on behalf of the environment, and to allow water permits to be traded between irrigators depending on relative need.

This involved calculating how much water could be taken from the river while ensuring a healthy ecosystem (the Sustainable Diversion Limit). Based on these calculations, state governments developed a water recovery program, which aimed to recover 2,750 gigalitres of water per year from consumptive use, through a A$3 billion water entitlement buyback and a A$9 billion irrigation modernisation program.

This program hinged on the development of water accounting tools that could measure both water availability and consumption. Only through trust in this process can downstream users be confident that they are receiving their fair share.

3. States retain control of water

Control of water was a major stumbling block in negotiating the Murray-Darling Basin Plan, because of a clash between states’ water-management responsibilities and the Commonwealth’s obligations to the environment.

As a result, the Murray-Darling Basin Authority sits outside of both state and Commonwealth governments, and states have to draw up water management plans that are subject to approval by the authority.

The states are responsible for enforcing these plans and ensuring that allocations are not exceeded. The Murray-Darling Basin Authority cannot easily enforce action on the ground – a situation that generates potential for state-level political interference, as alleged by the Four Corners investigation.

4. Trust and transparency

The Murray-Darling Basin Plan was built on a foundation of trust and transparency. The buyback scheme has transformed water into a tradeable commodity worth A$2 billion a year, a sizeable chunk of which is held by the Commonwealth Environmental Water Office.

Water trading has also helped to make water use more flexible. In a dry year, farmers with annual crops (such as cotton) can choose not to plant and instead to sell their water to farmers such as horticulturists who must irrigate to keep their trees alive. This flexibility is valuable in Australia’s highly variable climate.

Yet it is also true that water trading has created some big winners. Those with pre-existing water rights have been able to capitalise on that asset and invest heavily in buying further water rights, an outcome highlighted in the Four Corners story.

More than A$20 million in research investment has been devoted to ensuring that the ecological benefits of water are optimised – most notably through the Environmental Water Knowledge and Research and Long Term Intervention Monitoring programs. What is not clear is whether water extractions and their policing have been subjected to a similar degree of review and rigour.

What next for the Murray-Darling Basin?

The public needs to be able to trust that all parties are working honestly and accountably. This is particularly true for the downstream partners, who are the most likely victims of management failures upstream. Without trust in the upstream states, the Murray-Darling Basin Plan will unravel.

State governments urgently need to reaffirm their commitment to the four pillars that underpin the Murray-Darling Basin Plan, and to reassure the public that in retaining control of water they are operating in good faith.

Finally, rigour and transparency are needed in assessing the Basin Plan’s methods and environmental benefits, and the operation of the water market. The Productivity Commission’s review of national water policy, and its specific review of the Murray-Darling Basin Plan next year, will offer a clear opportunity to reassure everyone that the A$13 billion of public money that has gone into water reform in the past decade has been money well spent.

Only then will the fragile trust that underlies the water reform process be maintained and built.

Ross M Thompson, Chair of Water Science and Director, University of Canberra

This article was originally published on The Conversation. Read the original article.

Article: Forced Underground Streams

The link below is to an interesting article on streams that have been forced to flow underground. It is a very interesting read.

For more, visit:
http://environment.nationalgeographic.com/environment/photos/underground-rivers