Annual environmental water priorities in the Intersecting Streams 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 communities, Aboriginal representatives, partner agencies, and other stakeholders 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

The Intersecting Streams rely on rainfall in southern Queensland and connection across the New South Wales–Queensland border to generate flows that support rivers and wetlands in this area.

There was above average rainfall in the region from late 2021 to late 2022. This rainfall created periods of high flow across the Intersecting Streams, followed by an abrupt dry period from early 2023. Rainfall returned to some areas in spring 2023, bringing reasonable conditions over much of spring and summer. Notable flows in this period included peaks of up to:

• 8,500 megalitres (ML) per day in the Paroo at Willara gauge
• 2,500 ML per day in the Culgoa at Collerina gauge
• 1,300 ML per day in the Narran at Narran Park gauge
• 855 ML per day in the Warrego at Fords Bridge combined gauges
• 15,000 ML per day in the Moonie at Gundablouie.

This rainfall generated inflows to Narran Lakes and the Paroo and Warrego wetlands.

With dry to moderate and warmer conditions forecast over the coming months in the northern Basin, critical environmental demands may come back into focus, particularly in relation to connectivity in the new water year. In 2024–25, the focus will be on continued recovery and maintaining current system conditions where possible.

Partnering with Aboriginal peoples

Water for Country is environmental water use planned by the Department of Climate Change, Energy, the Environment and Water and Aboriginal people to achieve shared benefits for the environment and cultural places, values and/or interests.

We will continue to work with the Toorale Aboriginal Joint Management Committee:

• on a project with the Kurnu-Barkandji Aboriginal people to better understand the cultural, ecological and operational features on the western floodplain – this information will allow for better flows across the floodplain
• to support the development of a cultural water management plan
• to discuss how the Kurnu-Barkandji people want to be reflected in the Intersecting Streams Long-Term Water Plan update.

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.

Following wet conditions through much of 2021–22, rainfall began to subside in December 2022 and conditions became dry through 2023 until spring. Sporadic rainfall through spring and summer saw notable flow events in the Paroo, Warrego, Lower Balonne and Moonie. These systems are primed and expected to respond to future rainfall events.

Water managers have prepared annual 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. Dry to moderate conditions are forecast for the Intersecting Streams in 2024–25, which means water availability planning will follow the 'dry' and 'moderate' scenarios.

Key planned actions

Native fish

A key priority is to support native fish populations and provide opportunities for them to breed and disperse into secure habitats.

Waterbirds

In 2024–25, a small volume of water is likely to be retained in Narran Lake due to an extended period of inflows, which began in late 2021. This was followed by an event-based mechanism release, which saw the Commonwealth Environmental Water Holder arrange for flows to be released from an irrigation storage in early 2023 and inflows in early 2024. A priority is to ensure adequate vegetation condition and water levels should further inflows trigger a waterbird breeding event in spring 2024.

Vegetation

The water that reached Narran Lakes in late 2021, 2022 and early 2024 will further improve vegetation condition in the lakes system. Opportunities that arise in 2024–25 to increase the duration of inundation of water-dependent vegetation will be prioritised. Supporting vegetation recovery following the fire in the 2023 summer will be a priority for water managers. Flows in early 2024 did not provide sufficient inundation to the area, so spring and summer 2024–25 flows would be of great benefit to the recovering vegetation community.

Connectivity

In the Warrego River, flows inundated vegetation communities on the Toorale western floodplain wetland in late 2022, early 2023, and early 2024. Repeated inundation in 2024–25 will increase the vigour and diversity of wetland vegetation.

Flows and inter-system connections depend on rainfall occurring throughout the year. Connectivity between the Warrego and downstream Baaka – Darling rivers is the priority alongside maintaining connection when environmental water is delivered to the western floodplain.

Water for the environment will be delivered at Toorale in line with the priorities set out in the Toorale water management infrastructure operating and maintenance plan.

The Barwon–Baaka – Darling and Intersecting Streams Environmental Water Advisory Group will be consulted when there is no identified priority. This environmental water advisory group is being established and expected to be operational in the 2024–25 water year.

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