2023-24 watering events
- Early Season Stimulus Flow
- Barwon River connection flow
- Restoring Natural Flows (20 GL)
- Mallowa Creek
The Gwydir Environmental Water Advisory Group (EWAG) met in April to discuss how to use environmental water for the current water year and plan for the 2024-25 water year.
Early Season Stimulus Flow
The Early Season Stimulus Flow (ESSF) gave an early season productivity stimulus downstream to Pallamallawa in late September/early October 2023. This was the main outcome of the event. Because of irrigation orders in the system, we needed 5,000 ML to achieve the event objectives. We diverted some of this water into the Carole Creek and Mehi River systems to help native fish, including Murray cod. This water helped them to stay on nests.
Barwon River connection flow
On the end of the Early Season Stimulus Flow, we delivered another 4 GL into the Barwon River. This flow increased the connection between river systems and watercourses. We delivered this water into the Barwon via the Carole Creek and Mehi River.
Restoring Natural Flows (20 GL)
We started this event in November 2023, at an initial rate of 50 ML/day and recently increased to 100 ML/day. We directed this water into the Gingham Watercourse to fill major waterholes by the end of June 2024.
Mallowa Creek
We delivered water into the Mallowa watercourse from December 2023 to February 2024. In total, we delivered 7,950 ML. This delivery built on the last few years' rainfall, natural flooding and inflows, and environmental water deliveries. It has continued to make this system more resilient.
The remainder of the 2023–24 water year
At the time of the meeting, we expected significant rainfall for a large part of New South Wales and the Gwydir catchment. This rainfall was likely to generate higher river flows.
Restoring Natural Flows (20 GL)
We will continue to deliver water in the Gingham Watercourse until we fill Boyanga waterholes.
A Barwon River connection flow
We have identified a possible autumn flow into the Barwon from the Gwydir. We will hold these flows until later in the water year.
Watering the burned area of the Gwydir Wetlands State Conservation Area
We discussed the recently burned area (about 900 ha) on the Big Leather-Lower Gwydir, Old Dromana portion of the state conservation area. We proposed to use the forecast high flows to improve outcomes for the wetland vegetation communities, especially the marsh club rush.
2024–25 watering principles
The members agreed to use an adaptive watering approach to meet the needs of the Gwydir's changing climate. As such, members adopted a range of Water Management Principles for the most likely scenarios over the next 12 months. The draft 2024–25 Gwydir Environmental Water Plan will be distributed to the Environmental Water Advisory Group when completed.
