The Murray–Darling Basin Authority (MDBA) is the main government organization responsible for managing the Murray–Darling Basin in a way that protects the environment and ensures resources last. The MDBA is an independent government body that works with the states in the Basin to manage water resources for the benefit of the entire country. It reports to the Minister for the Environment and Water, a position held since May 2025 by Murray Watt.

The MDBA was created by the Water Act 2007 (Cth), a law introduced by the Howard government as part of "A National Water Plan for Water Security." This law was developed to address drought and the possible effects of climate change in Australia. It also aimed to meet Australia’s responsibilities under the Ramsar Convention on Wetlands. The 2007 Act was changed significantly in 2008.

The Chief Executive of the MDBA is Andrew McConville, who took over from Phillip Glyde and Dr. Rhondda Dickson. The Chair of the MDBA is Daryl Quinlivan, who replaced Sir Angus Houston after his four-year term ended in 2024.

Although the MDBA is a Commonwealth Government agency, an intergovernmental Murray–Darling Basin Ministerial Council (Ministerial Council) provides advice to help the MDBA prepare and carry out the Basin Plan. The Ministerial Council includes the Commonwealth Minister for Agriculture and Water Resources (who leads the Council) and one minister from each of the Basin states (Queensland, New South Wales, Victoria, and South Australia) and the Australian Capital Territory. The Ministerial Council introduced the Murray–Darling Cap in response to a 1995 report titled "An Audit of Water Use in the Murray–Darling Basin."

Role of the MDBA

In 2008, the Murray–Darling Basin Authority (MDBA) was created. This was the first time a single group made up of different government levels took charge of planning how to manage water resources together in the Murray–Darling Basin. The MDBA has responsibilities that include:

• making, carrying out, and making sure the Murray–Darling Basin Plan is followed
• giving advice to the minister about approving state water resource plans
• creating a service that helps people trade water across the Murray–Darling Basin
• measuring and watching water levels and conditions in the basin
• collecting information and doing research
• teaching the public and involving them in managing the basin's resources.

The Murray–Darling Basin Authority is an important part of the Australian Government's program called Water for the Future. This program has four goals:

• dealing with the effects of climate change
• keeping rivers healthy
• using water carefully
• making sure there is enough water available.

The MDBA also pays for studies about water life and provides information about freshwater plants and animals in Australia.

History

Since 1914, several agreements between governments have been made to manage water resources in the Murray–Darling Basin. Before the Murray–Darling Basin Authority was created, the five state and territory governments in the Basin managed water resources with little coordination. To address this issue, the Murray–Darling Basin Commission was formed in January 1988 under the Murray–Darling Basin Agreement. Its goals were to manage and fairly distribute water from the River Murray, protect and improve water quality in the River Murray and its tributaries, and advise the Murray–Darling Ministerial Council on water, land, and environmental management in the Basin. Disputes over water use in the Basin, including conflicts between farmers and environmental groups, began in the 1960s. These disputes are described in the book Cottoning on: Stories of Australian Cotton-growing by Siobhán McHugh (Hale and Iremonger 1996), which was nominated for the NSW Premier's History Prize in 1997. The Water Amendment Act 2008, introduced in December 2008, changed the Water Act 2007. This law moved responsibility for managing the Basin from the Murray–Darling Basin Commission to the Murray–Darling Basin Authority, creating an independent group of experts to manage the Basin in a comprehensive way for the first time.

As of November 2016, the Murray–Darling Basin Authority (MDBA) had been working on the Basin Plan for four years. The MDBA has published important reports, including:

• Basin environmental watering strategy
• Annual environmental watering priorities
• Constraints management strategy
• New water trade operating rules

The MDBA also created a water trading system across Basin states to improve water use efficiency.

During the summer of 2018–2019, large fish kills occurred in the Murray–Darling Basin. A report from the Productivity Commission in January 2019 stated, "The MDBA has conflicting roles. It helps basin governments (as their agent) to carry out the plan and must also ensure the plan is followed. These conflicts will become more serious in the next five years. The MDBA should be divided into two separate organizations: the Murray–Darling Basin Agency and the Basin Plan Regulator."

Murray–Darling Basin Plan

On 8 October 2010, the Murray-Darling Basin Authority (MDBA) released a major document called the Guide to the Proposed Murray–Darling Basin Plan. This plan aimed to protect the long-term health of the Murray–Darling Basin’s rivers, wetlands, forests, and floodplains. The guide explained that water allocations would be reduced, and more water would be directed to the environment to help ecosystems recover. The plan was the first step in a three-part process to address issues like overuse of water, drought, natural climate changes, and climate change.

The MDBA prepared the full Murray–Darling Basin Plan, which was released in November 2011. The plan proposed reducing water allocations by 2,750 gigalitres per year over seven years. The plan was approved by Tony Burke, the Minister for Sustainability, Environment, Water, Population, and Communities, on 22 November 2012. It was passed by the Australian Parliament on 29 November 2012. The MDBA is responsible for ensuring the plan is followed by law.

The main goal of the Basin Plan is to return about 2,750 gigalitres of water to the river system each year. The MDBA originally suggested that returning up to 7,600 gigalitres per year would help the environment, but this amount was not considered practical for communities or the economy. The plan sets limits on how much water can be used from the basin’s resources to protect the environment. It also includes goals for improving water quality, managing salt levels, and creating systems for trading water across the basin. The plan aims to balance the needs of the environment, the economy, and communities.

After the guide was released, many people in rural areas expressed concerns during public meetings. In Renmark, over 500 people attended a meeting, but the local hotel could only hold 250 people. The draft plan suggested reducing water use by up to 35% in the Riverland area, which worried farmers about job losses and reduced water flows. In Griffith, over 5,000 people attended a meeting where the local mayor said the plan could harm communities in the Murrumbidgee valley. Groups like the Victorian Farmers Federation and Wine Group Growers’ Australia shared these concerns. However, some groups, such as the Australian Conservation Foundation and Environment Victoria, supported the plan.

In a legal report from October 2010, the Australian Government Solicitor said the plan must consider the environmental, social, and economic effects of reducing water use equally. Some environmentalists and farmers in South Australia believed the MDBA should return more water to the environment. In October 2010, a parliamentary inquiry was started to study the plan’s economic impacts. In November 2010, the MDBA said it might delay releasing the final plan until early 2012.

In January 2011, Mike Taylor, then Chair of the MDBA, announced he would resign. He said the Water Act made it hard to balance environmental and economic needs. He was worried the plan would return less than 3,000 gigalitres of water to the basin. Prime Minister Julia Gillard and Water Minister Tony Burke disagreed, saying the plan’s goals were not compromised.

In May 2011, the Wentworth Group of Concerned Scientists stopped supporting the Basin Plan. They said the process was flawed and would cost too much money. They believed the plan would not fix the river system’s problems and wanted at least 4,000 gigalitres of water returned to the environment. In June 2011, a federal parliamentary committee, led by independent Tony Windsor, reported that returning 4,000 gigalitres of water to the environment could harm communities. The committee also said the river system could be protected without such large water cuts. The Australian Conservation Foundation disagreed, saying buying water from farmers was the best way to save the basin.

According to the Wentworth Group, the government originally planned to buy 2,750 gigalitres of water and increase groundwater use by 2,600 gigalitres at the same time in March 2011. Much of this groundwater is connected to rivers, but the plan did not include it in its calculations.

In late May 2012, a revised version of the plan was sent to state water ministers for review. It still recommended returning 2,750 gigalitres of water to the environment by reducing water rights. After many discussions between the government and states, and input from communities and other groups, the Basin Plan became law in November 2012.

Royal Commission into compliance with plan

In 2017, after reports that upstream states were not following the Murray–Darling Basin Plan, South Australian Premier Jay Weatherill asked the Federal Government to conduct a legal investigation or Royal Commission to find out who was responsible for "water theft" and whether upstream states were involved. When the Federal Government refused, Weatherill started a Royal Commission in South Australia in January 2018. The Weatherill government ended in 2019, and the Federal Government later prevented officials from the Murray–Darling Basin Authority (MDBA) from testifying at the Royal Commission. The Commissioner, Bret Walker SC, also asked the new South Australian Attorney-General, Vickie Chapman, for more time to complete the investigation, but this request was denied.

The Royal Commission’s report was released on 29 January 2019. Commissioner Walker strongly criticized the MDBA’s management. He stated that the process of setting limits on water use was a "major failure of process" and that "The MDBA and the Commonwealth Government of the day can be seen not to have followed the plain requirements of the Water Act." (p24)

Later, after large fish deaths in the Darling River, additional calls for investigations were made.