Annual environmental water priorities in the Gwydir catchment

Water managers will respond to rainfall and natural flows to provide flows for water-dependent assets in the Gwydir catchment.

Priorities for 2021–22

If heavy catchment rainfall triggers colonial waterbird breeding events in the wetland systems, water for the environment may be provided to support these events.

This season there may be water deliveries for basic ecological needs in the Carole Creek and Mehi and Gwydir rivers. We will prioritise stream connectivity and support for native fish communities during extended dry periods.

Substantial rainfall and river flows may initiate a small delivery of held water into the Gwydir Wetlands system, Mehi River, and Mallowa or Carole creeks this season.

Further details on watering priorities for 2021–22 can be found in the Gwydir Catchment – Water for the Environment: Annual Priorities (PDF 1.2MB).

Highlights from 2020–21

The Gwydir catchment experienced an increase in water availability in the later part of 2020, after a very dry period since 2017. Conditions continued to improve in early 2021, culminating in a major natural flood event across the Gwydir River floodplain during March and April. This natural flooding has reset the floodplain ecosystems, which will support strong productivity in the 2021–22 season ahead.

During the 2020–21 water year, water for the environment was used to return a portion of natural flows into the Gwydir Wetlands, Mehi River and Mallowa and Carole creeks. It was also used to support a small colonial waterbird breeding event that occurred in the Gingham Watercourse.

Breeding was detected in 18 waterbird species which included a small colony of great egrets, cormorants and magpie geese on the Gingham watercourse. Cormorants and darters were also detected nesting along the Lower Gwydir River.

The Department of Planning Industry and Environment and National Parks and Wildlife Service detected 9 frog species in spring and summer surveys. This included all 6 species known to breed in response to wetland flows.

As the season progressed, flows into the Mehi River and Carole Creek also provided an important contribution to flows further downstream in the Barwon River system.