Use of water for the environment in NSW: Outcomes 2020–21

This report summarises the use of water for the environment across New South Wales in the 2020–21 water year and highlights the ecological outcomes achieved.

Water for the environment is managed to deliver benefits for communities and important environmental assets across New South Wales. When communities and industries face significant challenges during dry times, our rivers and wetlands also do it tough. As more water returns to our river systems, we need to adapt our planning to ensure sites have the opportunity to recover and increase their resilience for future dry times.

New South Wales is home to a unique array of native plants and animals that rely on our rivers and wetlands to survive the boom and bust cycles that shape the Australian landscape.

Water for the environment is a share of the water available in our dams and rivers that is managed to support the ongoing health of local waterways.

Map of New South Wales showing water catchment areas, associated main waterways and locations of water for the environment deliveries made in 2020-21.

The Department of Planning, Industry and Environment – Environment, Energy and Science (DPIE – EES) is responsible for ensuring that water for the environment is managed in accordance with relevant statutory plans, including water sharing plans established under the NSW Water Management Act 2000 and the Basin Plan established under the Commonwealth Water Act 2007.

This outcomes report details the work we do in 9 water resource plan areas to support our river systems and meet the needs of native plants, native fish, waterbirds and other water-dependent wildlife:

  • Murray and Lower Darling Water resource plan area – 237,497 megalitres delivered to multiple sites in the Murray and Lower Darling catchments
  • Murrumbidgee Water resource plan area – 493,768 megalitres delivered to multiple wetlands an instream flows in the Murrumbidgee catchment
  • Lachlan Water resource plan area – 82,091 megalitres delivered to wetlands and instream flows in the Lachlan catchment
  • Macquarie–Castlereagh Water resource plan area – 150,730 megalitres delivered to the Macquarie Marshes and Macquarie River
  • Gwydir Water resource plan area – 20,752 megalitres delivered to watercourses in wetlands in the Gwydir catchment
  • Barwon–Darling Water resource plan area
  • Border Rivers Water resource plan area
  • Intersecting Streams Water resource plan area
  • Namoi Water resource plan area – 1565 megalitres delivered to watercourses and refuge pools in the Namoi catchment.

Visit our Water for the environment webpages for further information on what we do, how we make decisions and how we deliver environmental flows.

Executive summary

Maintaining and restoring the health of rivers and wetlands for future generations is the aim of our Water for the Environment Program. Our adaptive management approach allows us to focus our efforts on outcomes that can be achieved with the water that’s available in any given year.

In 2020–21, the DPIE – EES Water for the Environment Team managed the delivery of approximately 986,403 megalitres of water across 44 delivery events for the environment. This water for the environment was sourced from NSW, Commonwealth, and joint government water accounts and delivered to key sites across the state.

Planning for much of the state was based on a dry to moderate resource availability scenario. However, widespread rainfall and improved dam levels provided an opportunity for the program to pivot and target enhanced outcomes at sites across the state.

To begin the water year, teams focused on ongoing drought recovery efforts, providing water to refuge sites to support key populations of native fish, waterbirds, plants and other water-dependent wildlife. Where more water was available, teams worked to support restoration of habitat and expand areas of inundation to provide feeding, breeding and movement opportunities for native fish, waterbirds and frogs.

In natural flowing rivers we worked with other water agencies to protect some instream flows to provide benefits for communities and the environment.

We continued our work with community advisory groups to prioritise the sites to receive water and build on the successes of previous years. Where possible, we also managed our water reserves to hold some water in account for future dry times. We also collaborated with numerous landholders across the rivers and floodplains in which we work. Their support and cooperation are critical to the successful outcomes achieved.

Water was used strategically to:

Flow-dependent native vegetation icon
–  support native vegetation health


Waterbird icon
–  support water bird health


Connectivity and water flow icon
–  connect and replenish refuge sites, wetlands and rivers


Native fish icon
  –  support native fish health.

Key achievements

Murray and Lower Darling Baaka catchments

In 2020–21 we delivered 237 gigalitres of water to rivers, creeks and wetlands on private and public land. We:

  • oversaw management of environmental flows connecting Menindee Lakes and the Murray River for the first time in 12 months, aiding native fish recovery and instream productivity
  • worked with state and federal partner agencies, First Nations groups, recreational fishing clubs and riparian landholders, to connect rivers and floodplain wetlands on a landscape scale
  • managed flows that triggered breeding and movement of native fish, including the iconic Murray cod and threatened trout cod
  • managed flows that provided essential nesting and foraging habitat for up to 20% of the Australasian bittern population
  • delivered water for the environment to boost floodplain productivity and the aquatic food web
  • supported habitat health and plant growth
  • delivered water to several private wetlands using irrigation infrastructure and private pumping to support southern bell frog populations in the mid- and lower-Murray
  • managed the delivery of water for the environment into the Bottle Bend Reserve to support black box and lignum.

Murrumbidgee catchment

In 2020–21 we delivered 493 gigalitres of water to rivers, creeks and wetlands on private and public land. We:

  • connected the river with floodplain wetlands to provide habitat for threatened species including Australasian bitterns and southern bell frogs
  • used existing infrastructure to provide water to wetlands on the Lowbidgee floodplain
  • triggered breeding and movement of native fish
  • boosted floodplain productivity and the aquatic food web
  • replenished wetland refuges
  • worked with the Commonwealth Environmental Water Holder (CEWH) to manage environmental flows to Gayini and Yanga National Park, which triggered significant colonial waterbird breeding events
  • provided critical refuge habitat for native fish, turtles and frogs at sites throughout the catchment
  • worked with 2 private irrigation companies to deliver water to wetlands to support southern bell frogs, waterbirds and native plant life.

Lachlan catchment

In 2020–21 we delivered 82 gigalitres of water to rivers, creeks and wetlands on private and public land. We:

  • maintained key refuges including Booberoi Creek for native fish and the Great Cumbung Swamp for Australasian bitterns and southern bell frogs
  • supported a pelican breeding event to successful completion, and aquatic plants to complete their life cycle at Lake Brewster
  • provided additional floodplain inundation in the lower Lachlan, including unique wetland types, some for first time since the 2016 floods
  • supported a range of native wildlife and plant communities in anabranch creek systems and their floodplains
  • supported the highest number of waterbird species and total waterbird abundance recorded in the past 5 years of our annual spring ground survey.

Macquarie–Castlereagh catchment

In 2020–21 we delivered 150 gigalitres of water to rivers, creeks and wetlands on private and public land. We:

  • inundated core parts of the Macquarie Marshes to commence post-drought recovery of wetland vegetation communities
  • provided water to maintain stable river flows in the mid-Macquarie River to produce spawning of Murray cod and eel-tailed catfish
  • supported habitat and nesting opportunities for several species of non-colonial waterbirds including magpie geese, brolgas, Australian painted snipe and various species of ducks, waterhens and reedbed birds.

Gwydir catchment

In 2020–21 we delivered 20 gigalitres of water to rivers, creeks and wetlands on private and public land. We:

  • managed the delivery of NSW and CEWH water to the Gwydir wetlands to supplement inflows from upstream rainfall
  • detected breeding in 18 waterbird species
  • detected 9 frog species during spring and summer surveys
  • maintained water quality and water levels in refuge pools along the Carole Creek, Mehi and main Gwydir river channels
  • delivered water to Whittaker’s Lagoon on the Mehi floodplain to support native fish survival and attract birdlife
  • supported vegetation growth and recovery in the Lower Gwydir watercourse wetlands to provide habitat for waterbird species and encourage recruitment of frogs.

Barwon–Darling catchment

In 2020–21 no deliveries of water for the environment were made. During this water year we:

  • worked with partner agencies to protect ecological assets and functionality
  • partnered with Department of Primary Industries – Fisheries to monitor water quality
  • observed rainfall and natural flows that allowed a number of environmental water requirements to be met that connected habitats, triggered fish movement and inundated instream benches (sediments banks within the river channel) for improved productivity.

Border Rivers catchment

In 2020–21 no deliveries of water for the environment were made. During this water year we:

  • advised on the use of the Pindari stimulus flow to help recruitment of Murray cod and freshwater catfish
  • managed stimulus base flows set aside through the Water Sharing Plan for the NSW Border Rivers Regulated River Water Source Order 2021, which contributed to the replenishment of refuge pools and a small winter fresh to increase productivity and improve pre-winter condition of native fish
  • observed rainfall and resulting flows that provided small fresh events in the Severn River, downstream of Frazers Creek
  • observed rainfall and natural flows that provided small and large freshes in the Dumaresq River
  • observed rainfall and natural flows that included a continual base flow in the lower section of the Macintyre River.

Intersecting Streams catchment

In 2020–21 no deliveries of water for the environment were made. During this water year we:

  • operated dam structures in Toorale National Park and State Conservation Area to provide water from the Warrego River to connect to the Darling River.

Namoi catchment

In 2020–21 we delivered 1.5 gigalitres of water for the environment. We:

  • managed the delivery of flows to support and refresh the Peel River below Chaffey Dam to Woolomin.

A year in the catchments

The Water for the Environment Monitoring, Evaluating and Reporting (MER) Program monitors indicators of river and wetland health using 4 major themes:

  • river flows and connectivity
  • native vegetation
  • native animals, including waterbirds and frogs
  • native fish.

By monitoring these indicators, we can measure progress towards meeting Basin Plan and long-term water plan objectives. We are also able to continually improve how we deliver water for the environment to meet those objectives.

We monitor environmental flow events and long-term changes in vegetation condition and extent, as well as changes in waterbird and frog populations in response to water management. Our monitoring efforts focus on wetlands targeted by water for the environment, including the Gwydir Wetlands, Macquarie Marshes, Lower Lachlan Wetlands, Lowbidgee Floodplain and Millewa Forest. We have also extended our monitoring efforts to the Snowy River, in partnership with the Department of Planning, Industry and Environment – Water.

We use a variety of technologies to determine whether the environmental water requirements of our river and wetland ecological communities are being met. This includes:

  • satellite imagery to track floodplain wetland inundation and changes in vegetation extents
  • aerial and ground surveillance to understand vegetation and waterbird responses to the water for the environment deliveries
  • acoustic recordings and observation to monitor frogs.

We work with the Commonwealth Environmental Water Holder (CEWH) to deliver water for the environment and ensure improvements to the health of rivers and wetlands in the most effective way. This efficiency extends to monitoring. We collaborate with the CEWH, independent researchers, tertiary institutions, and community groups to improve our understanding and prevent duplication of effort.

We report our findings to the Murray–Darling Basin Authority to meet Schedule 12 requirements of the Basin Plan. Schedule 12 includes annual reporting of ecological outcomes at an asset-scale (Matter 9.3) and a 5-yearly evaluation (Matter 8). The 5-year evaluation is due in 2025. We also provide regular updates to the community through our website and stakeholder engagement.

An independent evaluation of our Water for the Environment MER Program between 2014 and 2019 has also been completed and these findings will be made publicly available later in 2021.

The year in review

Following a dry start to the 2020–21 water year, widespread rainfall across the NSW Murray–Darling Basin resulted in wetter conditions as the year progressed. Increased storage levels enabled water for the environment to be delivered to river and wetland habitats across the state. Targeted habitats included non-woody wetland vegetation, river red gum forests and woodlands, black box and coolabah woodlands and lignum shrublands.

The aim of these deliveries was to support long-term water plan objectives. For example, improved connectivity and inundation across rivers and wetlands included watering:

  • 37,705 hectares of Lowbidgee wetlands
  • 8919 hectares of Barmah-Millewa forests
  • 40,194 hectares of wetlands in the mid and lower Lachlan
  • 30,191 hectares of the Macquarie Marshes
  • 236,718 hectares of the Gwydir floodplain, including Ramsar-listed wetlands.

The increased areas of wetland habitat and watercourse connectivity improved riparian and floodplain vegetation condition, and supported waterbird and frog breeding.

Waterbird surveys

At the start of the water year, waterbird surveyors in the Gwydir Wetlands, Macquarie Marshes, Mid and Lower Lachlan, Murrumbidgee and Murray wetlands encountered numerous dry sites, with waterbird habitats confined to watercourses and isolated waterholes.

Over the spring and summer, following widespread rainfall and the delivery of water for the environment to wetlands across the NSW Basin, wetlands filled and waterbird habitats increased.

Over this wetter period, we found 51 waterbird species in the Gwydir Wetland System. This included 5 NSW-listed threatened species (freckled duck, black-necked stork, brolga, back-tailed godwit and magpie goose) and 4 migratory shorebird species (Latham’s snipe, sharp-tailed sandpiper, black-tailed godwit and wood sandpiper). There was also an incidental sighting of a nationally endangered Australasian bittern on the Gwydir State Conservation Area in early March 2021. Breeding was detected in 18 waterbird species (including 6 colonially-nesting species) during the 2020–21 surveys.

We observed a high number of waterbirds in the Macquarie Marshes. The 48 waterbird species detected included 3 threatened waterbird species (Australasian bittern, brolga, magpie goose), and large numbers of grey teal, Pacific black duck, hardhead and Eurasian coot. At least 3 colony sites were found in the northern marsh, with 8 additional waterbird species nesting in small numbers, including the Australasian darter, Australian white ibis, little pied cormorant, little black cormorant, eastern great egret, cattle egret, intermediate egret and magpie goose. Other notable waterbird species observed were the migratory Latham’s snipe and wood sandpiper, and the blue-billed duck which is listed as vulnerable in NSW.

In the Mid and Lower Lachlan, we observed 55 species of waterbirds including blue-billed ducks and magpie geese, as well as migratory shorebird species (sharp-tailed sandpiper, Latham’s snipe and red-necked stint) recognised under international migratory bird agreements. The nationally endangered Australasian bittern was heard calling, which was significant as there have been few records of Australasian bitterns in the Great Cumbung in recent decades – the last confirmed record was in 1991. Inundated wetlands also provided habitat for breeding, with 6 active waterbird colony sites identified.

Twenty active waterbird colonies were found in the Murrumbidgee. This included a large ibis colony in the Gayini Wetlands, and smaller ibis, egret, spoonbill, heron and cormorant breeding sites across the rest of the Murrumbidgee catchment. The nationally endangered Australasian bittern, NSW-listed vulnerable blue-billed duck and freckled duck were also found at several Lowbidgee floodplain sites.

Surveys in the Barmah–Millewa Forest under The Living Murray Program identified 48 waterbird species which was a significant increase from the 36 species recorded in 2019–20. Australasian bitterns were recorded calling at Moira Lake and successful breeding of spoonbills, cormorants and ibis was observed.

Frog surveys

Over the 2020–21 summer, natural inflows and the delivery of water for the environment supported frog breeding across many monitored sites.

Nine flow-responsive frog species were identified in the Gwydir over spring and summer. Detected species included spotted marsh frogs, eastern sign-bearing froglets, barking marsh frogs, Peron’s tree frogs, broad-palmed frogs and salmon-striped frogs. Although frog breeding activity was relatively low in spring 2020 due to dry conditions, activity increased for all species over summer following wetland inundation by natural flows and the provision of water for the environment.

Surveys in the Macquarie Marshes also found high levels of frog breeding success. Eight frog species were detected, including all 6 flow-dependent species (spotted marsh frog, barking marsh frog, Eastern sign-bearing froglet, Peron’s tree frog, broad-palmed frog and salmon-striped frog) and 2 arboreal frog species (green tree frog and desert tree frog).

The presence of the nationally vulnerable southern bell frog in the Lower Lachlan was confirmed at 2 locations in the Lachlan’s Great Cumbung Swamp. These latest records of nationally listed threatened species are significant for the Lower Lachlan which was once a stronghold for these species. Southern bell frogs were last confirmed in the Lower Lachlan in 2012.

Monitoring in the Murrumbidgee, as part of a long-term Commonwealth program, found frogs actively calling at most sites that received water for the environment. Southern bell frogs were heard calling at multiple wetlands in Yanga National Park and the Gayini Wetlands, with large choruses also heard at Sunshower Lagoon in the mid-Murrumbidgee.

The Saving our Species southern bell frog conservation project monitored the outcomes for water for the environment in the mid- and lower- Murray regions. Southern bell frogs were found at 15 of 19 monitored sites in the Mid-Murray and 2 monitoring sites in the lower-Murray region.

The Department of Planning, Industry and Environment – Environment, Energy and Science (DPIE – EES) is the lead agency for the delivery of water for the environment in New South Wales. This includes collaboration on the delivery of Commonwealth water held by the Commonwealth Environment Water Holder.

This figure summarises current water holdings, or State ‘held’ water for the environment, recovered to 30 June 2021 (megalitres).

Bar chart showing held environmental water for each valley in New South Wales for the 2020-21 water year.

Water trade

Our business model allows for the periodic trading of water to cover some of the charges involved in holding and managing water licences. Our trades are modest and usually less than 2% of the water available to the environment within a water year.

Funds may also be used to purchase water or implement small-scale projects that improve the outcomes of watering events. In 2020–21, the department sold 1765 megalitres of environmental groundwater allocation and 1060 megalitres of environmental surface water allocation. Future trade will continue to manage the portfolio for maximum environmental benefit.

More information about understanding water trade is available.

We work with a range of partner agencies, organisations and individuals to achieve/secure effective and efficient delivery of water to our rivers and wetlands.

These include:

  • Commonwealth Environmental Water Office
  • Department of Primary Industries – Fisheries
  • Department of Planning, Industry and Environment – Water
  • First Nations peoples
  • landholders
  • Murray–Darling Basin Authority
  • Murray Lower Darling Rivers Indigenous Nations
  • Northern Basin Aboriginal Nations
  • Northern Basin Environmental Water Group
  • NSW Environmental Water Advisory Groups
  • recreational fishers
  • Southern Connected Basin Environmental Water Committee
  • universities
  • Water NSW.

More information about some of our partner agencies is available on our terms and definitions webpage.