Annual environmental water priorities in the Gwydir catchment 2024–25

Water that is allocated and managed specifically to improve the health of rivers, wetlands and floodplains is known as water for the environment.

Our environmental water management teams work with local community advisory groups including landholders, Aboriginal stakeholders, partner agencies and other interested community members to develop detailed annual plans for the use of water for the environment in each catchment, including how its use is prioritised.

Water for rivers and wetlands

Moderate rainfall and constant river flows were experienced across the Gwydir catchment during 2023–24. Major flooding occurred across the Gwydir River floodplain during March and April 2023.

Water managers used water for the environment during the 2023–24 water year to support fish communities in rivers and create connections to the Barwon River, the Mallowa Creek, and low flows into the Gingham Watercourse to fill waterholes by season’s end.

In planning for 2024–25, water managers have applied:

• a set of principles and triggers to guide the watering of key water-dependent assets
• an adaptive approach to support fish and downstream ecological connectivity.

Measures are in place to provide water for unforeseen water demands, such as extended dry periods, wetland fires and colonial waterbird nesting.

The Department of Climate Change, Energy, the Environment and Water (the department) may also set aside water for use in future years to support the longer-term resilience of the catchment through drier times.

Partnering with Aboriginal peoples

Water for Country is environmental water use planned by the department with Aboriginal peoples to achieve shared benefits for the environment and cultural places, values and/or interests.

We are working to support Aboriginal people to participate in environmental water management, programs and decision-making processes across the Gwydir catchment, through:

• support for the Aboriginal representatives on the Gwydir Environmental Water Advisory Group
• creation of the Gwydir First Nations Environmental Water Group. This group was set up to promote the views of Aboriginal communities in the Gwydir through the environmental water advisory group process and other water management programs
• partnership with the local community group OzFish Chapter, having a positive approach to connecting local community with water for the environment programs. As an ‘on Country living classroom’, OzFish engage with local Moree students at Whittaker’s Lagoon, a place of both cultural and environmental importance.

Weather and water forecast

As of June 2024, the El Niño–Southern Oscillation outlook is neutral. That is, neither La Niña nor El Niño conditions are favoured as oceanic and atmospheric indicators have returned to neutral levels. International climate models suggest neutral El Niño–Southern Oscillation conditions will persist through the southern winter, but there are some signs that La Niña conditions could form later in the 2024–25 water year.

Water managers have prepared watering plans that consider a range of weather and water availability scenarios. This is known as resource availability scenario planning.

Resource availability scenario

This table provides details about how we plan for different resource availability scenarios. Moderate to dry conditions are forecast for the Gwydir catchment in 2024–25, which means water availability planning will follow the ‘dry’ and ‘moderate’ scenarios.

Key planned actions

Native fish

Water managers may use up to 25 gigalitres (GL) to support native fish communities. In the absence of large natural flows, a release downstream of Copeton Dam will stimulate early-season river productivity and support environmental flows later in the season.

Waterbirds

Heavy catchment rainfall, resulting in large river flows and floodplain flooding, may trigger waterbird breeding events in the wetland systems. In response, 15–25 GL of held water for the environment may be provided to support these events.

Vegetation

Water managers may use up to 20 GL across the catchment. Rainfall may trigger the delivery of held environmental water into the Mehi River, Carole Creek and/or the Gwydir wetlands system. Flows may be provided to Mallowa Creek to continue ecological improvements as part of seasonal planning for this watercourse.

Connectivity

Water deliveries for basic ecological needs in the Carole Creek, Mehi, and Gwydir rivers may occur this season if needed. The aim is to provide instream connectivity and support of native fish communities during extended dry periods. In addition to intra-catchment connectivity, water managers may consider addressing connection to the Barwon River if warranted during the year.

Map of proposed annual priority targets in the water resource plan area 2024–25