The Murray–Darling Basin in southeastern Australia is a wide catchment that extends across four states and the Australian Capital Territory, covering more than a million square kilometres and representing about one-seventh of Australia’s total land area. Its management is one of Australia’s largest and most complex environmental challenges.
Containing six of Australia’s seven longest rivers (the Murray, Darling, Paroo, Warrego, Murrumbidgee and Lachlan), the Murray–Darling Basin links up several lakes and important wetlands, including 16 that are listed under the Ramsar Convention. These include the large Macquarie Marshes, near Coonamble, and the chain of nine Menindee Lakes, in the far west of New South Wales, not far from Broken Hill. Near the mouth of the Murray, it enters the Coorong, a shallow and very long lagoon, before reaching the ocean southeast of Adelaide.
Since large-scale irrigated farming began in the Murray–Darling Basin during the 1970s, Australia has grappled with balancing this water-intensive agriculture with the environmental flows needed to keep the river system in good health, while supplying cities and towns that use Murray–Darling water. Management of the system is shared across the relevant states and the Commonwealth and is governed by the Murray–Darling Basin Plan water-sharing roadmap. Irrigation water allocations have become politicised, and the National Party in particular has a history of being heavily pro-irrigation.
Water challenges in the basin are heightened because the level of flow cannot be predicted. The Millennium drought affected the basin from 2001 to 2009, and more recently a dry period between 2017 and 2019 was considered the most intense short drought in 120 years’ worth of records. At the time of writing in early 2022, there is currently a lot of water in the system, following substantial rain in the catchment during a La Niña cycle. Water passes slowly through the system, and lingers for a fairly long time.
Considering the environment
Ecologically, the basin has experienced degradation and biodiversity erosion. It is threatened by land clearing and the loss of habitat, grazing by feral animals, climate change and diversion of water for agriculture. The problem of salinity is worsened by native vegetation clearing, flooding for irrigation and low river flows. Threatened species include the Murray cod, Australia’s largest freshwater fish, and the plains-wanderer, a well-camouflaged bird that likes grassland habitats.
As you travel downstream, the water level is likely to drop, and if you’re unlucky you could find yourself on a dry river bed, as happened in the lower reaches of the Darling during the last drought. While the Murray–Darling Basin normally cycles between wet and dry periods, the drier periods are growing more frequent and intense. Over the past 20 years, long-term-average total flows have nearly halved, causing some concern.
When the rivers reach a point where their creek beds are dry, natural and human-made drought refuge habitats become an important means of restocking the river with aquatic life when the water comes back. In relation to possible long-term effects on the river’s biodiversity from dry conditions, there is a lot of scientific uncertainty about their ability to rebound.
Could the Murray–Darling Basin survive another Millennium drought? According to Craig Wilkins from the Conservation Council of South Australia, it led the river system to become bordering on a “whole system collapse”. River red gums in the Macquarie Marshes wetland area were stressed, and some died. Parts of the Coorong became five times saltier than the sea, killing native plants and animals. In January 2019 at the Menindee Lakes, mass fish kills briefly became front page news.
Climate change is likely to lead in the future to hotter and drier conditions, with an increase in droughts. CSIRO scientist Francis Chiew has estimated a 20 to 40 per cent reduction in flow through the system by 2070. The Murray–Darling Basin Plan has come under severe criticism for not taking the expected effects of climate change into account.
Investment funds can play a role in steering the Murray–Darling towards greater health. A few years ago, VicSuper invested A$200 million in its Farming Landscapes Trust near Swan Hill in northern Victoria. The aim is to restore the health of 37 farms, representing 9150 hectares of salinity-affected farming land, by pursuing agricultural activities with sustainability goals in mind.
Farming in the Murray–Darling basin
The importance of the Murray–Darling to Australia’s agricultural sector cannot be overstated. This zone produces nearly 100 per cent of the country’s rice, 80 per cent of grapes and 28 per cent of dairy products. It accounts for about 40 per cent of the country’s food production. Farming in the basin is dominated by irrigation techniques.
Cotton farms at the northern part of the basin in southwest Queensland and northwest New South Wales have attracted the most criticism. Cubbie Station, near Dirranbandi, is Australia’s largest cotton farm and the largest irrigated farm in the Southern Hemisphere. Dryland cotton can also be grown, but is chancy, depending on sufficient soil moisture and rainfall.
In recent years, some higher-value irrigated crops such as almonds have become increasingly seen as a good growth-sector investment and have attracted institutional investors. Almonds are also thirsty, with one figure from California estimating that 12 litres of water are needed to grow one single almond.
Southern basin irrigators’ groups such as the Southern Riverina Irrigators, associated with the Murrumbidgee Irrigation Area, tend to feel that too much water is going to the northern basin cotton growers. As a result of worsening water security and quality, the area of irrigated grapes in the Menindee region has been steadily shrinking, and most growers have sadly exited the industry.
Floodplain harvesting is a term for the capturing of water falling on or flowing across a property by using banks and levees to divert it into dams and storages. Having operated unregulated in New South Wales for decades, it was recently given a formal stamp of approval. A 2020 investigation by the Wentworth Group of Concerned Scientists found that rivers were missing about 20 per cent of their expected flows under the plan, with floodplain harvesting a likely contributing factor.
Issues with irrigated farming in the Murray–Darling Basin were highlighted by the ABC show Four Corners in its 2017 episode “Pumped”. One observation has been the prevalence of broken or disconnected meters to attempt to avoid paying for water, despite laws requiring modern tamper-proof meters and the maintenance of log books.
The water market
To manage the allocation of water in the basin, a water trading system was established during the 1980s. Operating as a market-based response to water allocation, it uses a “cap and trade” model based on a finite limit of water availability. “Water rights” are sold and purchased, and water sold by an owner in one location can be used elsewhere in the basin.
This lucrative market has attracted a range of players, including traders, brokers and hedge funds. Once a small part of the picture, over the years their share of the market has steadily grown. The water market operates under a low-regulation model, and unlike the financial markets, there are no rules against manipulating it for profit.
Small farmers have valid concerns about speculators pushing up the price of water and can find it hard to compete in the market. During drought periods when farmers need water the most, they are liable to be struggling financially and may be priced out from buying what they need. One effect of this has been to increase water use because when it previously lacked a market value it went unused in one location without boosting allocation elsewhere.
When the Commonwealth Government purchases water allocated for irrigation to use for other purposes such as boosting environmental flows, it is known as a “buyback”. A second means of saving water, preferred by the government, is through subsidies for improving irrigation efficiency, but these are at least 2.7 times more costly in terms of value for money.
Manager and regulator
At a Commonwealth level, the overarching body responsible is the Murray–Darling Basin Authority (MDBA), and it has been heavily criticised for a variety of reasons. A 2019 Royal Commission found what it described as major shortcomings, including negligence, maladministration and unlawful actions. The MDBA was judged to operate under a culture of unnecessary secrecy, and its plan ignored the risks of climate change. The report emphasised a need to revise the plan, with more water diverted from irrigation into the environment.
As with some other government bodies, the MDBA appears to have succumbed to the politicisation of decisions. A 2010 draft document recommended that 6900 gigalitres (Gl) be returned to the river to achieve a “low uncertainty” of achieving desired environmental outcomes. When 2750Gl was allocated for the environment under the plan in 2012, concern was raised that this was decided according to politics rather than science. The figure was further lowered by a 2014 decision by the Abbott government to cap buybacks to 1500Gl.
Another 2019 report by the Productivity Commission recommended that the MDBA should be broken up. At present, it fulfils the dual roles of manager and regulator, which are often in conflict.
Scientists, activists and environmental groups
Among those speaking out about the Murray–Darling is:
- The Wentworth Group of Concerned Scientists, lists water among its key areas of focus. It characterises itself as independent and offers much-needed scientifically based scrutiny.
- The Nature Conservation Council of NSW is that state’s peak environmental lobby group. It is currently running a court challenge against the state government in a bid to block the Border Rivers Water Sharing Plan (WSP.) The primary argument is that this plan fails to consider climate change.
- Tolarno Station, a farm in the Menindee Lakes region of NSW, is largely involved with farming sheep. It is also vocal about local water issues, and can be followed on Facebook.
- JR, is a French artist who is identified by the abbreviated form of his name. In February 2021, he used the dry state of part of the Murray–Darling as a springboard for his conceptual art. This involved creating large, 30-metre cloth images of three local citrus farmers and Barkindji artist William “Badger” Bates, which were later carried onto the dry river bed at Lake Cawndilla, one of the Menindee Lakes in western NSW, by numerous people in a symbolic walk likened by the artist to a funeral march. This was photographed from above and attracted some media coverage.
Indigenous connections to the Murray–Darling Basin
For Indigenous tribes occupying the basin, including the Barkindji people living near the Darling, the river system has a particularly important historical, cultural and spiritual significance. Water represents so much more than a commodity. Where a river such as the Baaka (Darling) runs dry as a consequence of human interference, this is very painful for the local Indigenous community.
Water allocations for specific Indigenous uses are often referred to as cultural flows and may be for purposes such as fishing, hunting, ceremonies and gathering medicinal plants. These handovers are supported by the Murray–Darling Basin Authority but have not yet been granted. Often they involve culturally significant natural features, an example of which is Margooya Lagoon (also known as Tol Tol), a culturally significant wetland located near Robinvale in Victoria. The local Tati Tati traditional owners are looking for a small buyback, and this is currently at the discussion stage.
Learning from Uzbekistan
In what sounds like a case of déjà vu, starting in the 1960s the Soviet Union diverted two rivers from flowing into the Aral Sea, a body of water split between Uzbekistan and Kazakhstan, instead using it for growing cotton in massive irrigated projects. Over the decades, this loss of inflow has caused the Aral Sea to largely disappear.
It is easy to ignore the Murray–Darling Basin. Geographically it is remote from population centres, especially pockets of environmental activism in the inner suburbs of metropolitan areas. It is also very large, making it hard to grasp as a whole system. It fails to receive very much media, except during major droughts. The ongoing controversy over water allocations and the competing narratives are at times confusing.
Fortunately, it is on many people’s radars. Engagement with environmental issues continues to grow, and the basin is no exception. When I read one story about water and Murray–Darling irrigation in an Australian media outlet, I was struck by the way in which every comment without exception seemed to be united in its rejection of business as usual, a remarkable circumstance in today’s polarised society.
