The Australian Government owns entitlements to water in the Murray-Darling Basin. This water is used to keep our rivers healthy, so they may continue to support communities for future generations. This water is referred to as water for the environment.
The water in our rivers and dams is shared by many different users. Managing water for the environment is the job of the Commonwealth Environmental Water Holder (CEWH). From October 2022, Simon Banks holds the role of the CEWH. The CEWH is just one of many water holders in the Murray-Darling Basin, and is subject to the same fees, allocations, carryover and rules as other water users.
The CEWH is an independent statutory position established under the Water Act 2007. The CEWH leads, and is supported by, the Commonwealth Environmental Water Office (CEWO). The CEWO is a division of the federal Department of Climate Change, Energy, the Environment and Water.
How we operate
Every year is different and the amount of water available changes from year to year. The CEWO makes decisions annually on how best to use the water it has available. The CEWO works with local landholders, water managers and First Nations using an annual water management cycle to plan, deliver, measure and review the use of water for the environment.
Many different people and organisations work with the CEWO to decide how, when and where water for the environment will be delivered across the Basin. Some of the CEWOs delivery partners include:
- State government land managers and environmental water holders: work with the CEWO to deliver environmental flows at local sites.
- River operators: manage government storages on the rivers, including planning and delivering environmental flows.
- Scientists: research how best to use water to help the environment and monitor whether it’s making a difference.
- First Nations peoples: provide guidance on how environmental flows can meet cultural objectives.
- Local communities and interest groups: input into how, when and where water is delivered.
- Murray-Darling Basin Authority: sets limits on water use through the Murray-Darling Basin Plan, provides advice on Basin-wide priorities and runs the River Murray system.
The Basin spans southern Queensland, the Australian Capital Territory, much of New South Wales, over half of Victoria and the southeast of South Australia. The Commonwealth environmental water portfolio is large and complex with 80 water entitlement types across 17 Basin Plan regions.

Delivering water for the environment with Renmark Irrigation Trust.
Decision making
Environmental water is often used to supplement other water in the system. Depending on river operating rules, flow constraints, and climatic conditions, the Commonwealth Environmental Water Holder can agree to:

- Use the water to meet identified environmental demands. More information on use and managing water can be found at: Water Use framework
- Hold on to the water and carry it over for use in the next water year (‘carryover’). More information on carryover, can be found at: Carryover
- Trade (sell or buy water) for equal or greater environmental benefit. More information on how trading works can be found at: Water Trading Framework
Planning – how to get the most out of every drop!
Careful planning is critical to get the most for the environment out of every drop of water available.
The CEWO works closely with many people and organisations to plan our water use. The CEWO are grateful for their contributions and look forward to working together to deliver water to keep our rivers flowing and healthy. Planning overviews for the northern and southern regions of the Basin are available at: Water Management Plan 2022-23 Summary Brochures.
How our planning fits under the Basin Plan
The CEWO provides water across the Basin to meet environmental priorities and targets set out under the Basin Plan. It is the Murray-Darling Basin Authority’s (MDBA) job to set these priorities each year and the CEWO’s job to deliver water to meet them where possible.
The environmental watering strategy can be found at the Murray-Darling Basin Authority - Basin-wide environmental watering strategy 2014.
Water Holdings
As at 31 July 2023, the Commonwealth environmental water holdings total 2,888,695 megalitres of registered entitlements with a Long term average annual yield of 2,000,662 megalitres.
For more information see:
*Previous years are available in a table below.
Water use
The figure below shows water availability and water use as at 30 June each year from 2008-09 to 2023-24. As at 31 July 2023, 15,075 gigalitres of Commonwealth environmental water has been delivered to rivers, wetlands and floodplains of the Murray-Darling Basin.
Carryover against the Commonwealth’s regulated southern-connected basin entitlement into 2023-24 was 548 GL. This equates to 32 per cent of the aggregate southern-connected basin entitlement of 1,729 GL where carryover rules apply. The maximum allowable carryover within state carryover rules against these entitlements is 1,074 GL, or approximately 62 per cent.
In the northern Basin, carryover against the Commonwealth’s regulated surface water entitlement into 2023-24 was 429 GL. In the northern Basin most catchments have continuous accounting rules, and there are no carryover limits applied at the end of a water year. These rules are designed to provide capacity for substantial carryover for all entitlement holders because inflows and allocations are more variable than in the south of the Basin.
For detailed information on water delivered in each catchment of the Murray-Darling Basin, see the Water use page for each individual Catchment.
*Previous years are available in a table below.
Previous water holdings
Year | Entitlements | Long term average yield (LTAAY) |
---|---|---|
2008-09 | 65 | 39 |
2009-10 | 738 | 485 |
2010-11 | 993 | 679 |
2011-12 | 1,368 | 984 |
2012-13 | 1,632 | 1,192 |
2013-14 | 2,126 | 1,454 |
2014-15 | 2,309 | 1,592 |
2015-16 | 2,432 | 1,692 |
2016-17 | 2,562 | 1,780 |
2017-18 | 2,706 | 1,859 |
2018-19 | 2,847 | 1,952 |
2019-20 | 2,876 | 1,989 |
2020-21 | 2,877 | 1,990 |
2021-22 | 2,877 | 1,991 |
2022-23 | 2,889 | 2,001 |
Previous water use
Year | Annual Allocation (GL) | Carryover (GL) | Water delivered (GL) |
---|---|---|---|
2008-09 | 14 | 13 | |
2009-10 | 187 | 154 | |
2010-11 | 690 | 34 | 387 |
2011-12 | 979 | 331 | 680 |
2012-13 | 1,112 | 565 | 1,272 |
2013-14 | 1,056 | 394 | 982 |
2014-15 | 1,021 | 450 | 1,014 |
2015-16 | 1,007 | 444 | 1,049 |
2016-17 | 1,721 | 361 | 1,453 |
2017-18 | 1,198 | 612 | 1,270 |
2018-19 | 885 | 526 | 853 |
2019-20 | 1,076 | 509 | 1,198 |
2020-21 | 1,828 | 333 | 1,376 |
2021-22 | 2,541 | 738 | 2,016 |
2022-23 | 1,682 | 1,081 | 1,360 |