OPINION: The Commonwealth Environmental Water Holder (CEWH) manages the water that has been recovered under Basin Plan initiatives including water efficiency projects and water purchases. In the Murrumbidgee, the CEWH manages a portfolio of High Security, General Security and Supplementary entitlements. Entitlements managed by the CEWH retain the same characteristics and rules (i.e. allocation, carry over and fees) as other licence holders.
Amongst the debate on water buybacks, a common question we hear is how are we using all the water recovered to date? How is this water benefitting our local wetlands, plants and animals?
Commonwealth Environmental Water in the Murrumbidgee valley
Under the Murray-Darling Basin Plan, water has been recovered to keep our rivers and wetlands healthy. This water is managed by the Commonwealth Environmental Water Holder (CEWH).
In the Murrumbidgee valley, the CEWH has 782 gigalitres of surface water entitlements. Over the long-term, this provides on average 418 gigalitres of water each year.
There is a mix of different entitlement types. This includes 286 gigalitres of General Security entitlements and 429 gigalitres of Supplementary entitlements. The CEWH is subject to the same fees, allocations, carryover, and rules as other water users.
Many people may not know that we use the majority of this water to benefit the local environment. Water recovered in the Murrumbidgee valley is being used in the Murrumbidgee valley. We work with NSW government agencies, irrigator operators (such as Murrumbidgee Irrigation and Coleambally Irrigation), local landholders, First Nations peoples and interested community groups to plan and deliver the water.
We also measure and monitor its use. This means we know what outcomes we are achieving. The results inform our plans and help us innovate to get even better outcomes next time.
Examples of how Commonwealth environmental water is benefitting the Murrumbidgee valley
There are lots of important wetlands throughout the Murrumbidgee valley. There are around 1100 wetlands lining the Murrumbidgee River between Wagga Wagga and Hay. Below Hay, the river breaks out into a vast floodplain, known as the “Lowbidgee floodplain”. The Yanco Creek system (which includes Colombo Creek and Billabong Creek) has large wetlands, billabongs and more than 800 kilometres of creeks.
McCaugheys near Yanco, is one of the many wetlands along the Murrumbidgee river between Wagga and Hay. Photo: Michele Groat
Commonwealth environmental water is rejuvenating many of these wetlands and floodplains. It is resulting in healthier plants and increased diversity of plants. It is also providing critical habitat for fish, turtles, frogs, rakali (water rats) and fishing bats.
Sunshower near Darlington Point, transforming after receiving water for the environment
The Lowbidgee floodplain is one of the most important waterbird nesting areas in the Murray-Darling Basin. It is particularly important for ibis, herons, pelicans, egrets and cormorants. In 2023, the Lowbidgee floodplain supported more than 25 percent of waterbirds breeding in the basin. This included more than 98,000 straw necked ibis nests and 21,000 pelican nests. During these nesting periods, we often ‘top up’ the wetlands with environmental water. This keeps the water levels stable, so the adult birds don’t abandon their nests. It can also reduce the risk of nests becoming accessible to predators like foxes and pigs. We sometimes provide flows to flush the wetlands. This aims to maintain water quality and minimise the risk of disease.
Pelican’s at Gayini on the Lowbidgee floodplain.
Native fish breeding, movement and survival
Native fish populations in the Murray-Darling Basin have declined by more than 90% over the past 150 years. Factors that have contributed to this decline include:
- changes to the timing and size of flows down the river
- barriers to fish movement
- poor water quality
In the Murrumbidgee valley, environmental water is helping to address these threats. This includes providing flows:
- at the right time of year (particularly at the right temperature) to support golden and silver perch spawning
- that connect the river with wetlands that provide nursery habitat for baby fish
- that allow fish to move back and forth between the Murray and Murrumbidgee rivers
- that mitigate low oxygen water, which can occur in both droughts and floods and cause mass fish deaths.
CSU’s Lachlan Spalding, setting nets in Yanco Creek to monitor native fish. Photo: Anna Turner
Commonwealth environmental water is playing a vital role in the Murrumbidgee valley. It is benefiting the region’s birds, native fish, wetlands and floodplains. This water is not diverted away from the region. Instead, it is carefully managed to restore and protect the Murrumbidgee environment we all live in.