Annual environmental water priorities in the Murrumbidgee

Improving the health of wetlands and floodplains is the continued focus of water for the environment in the Murrumbidgee valley.

Priorities for 2017–18

In 2016–17, the Murrumbidgee valley experienced very wet conditions with very high inflows. This resulted in widespread inundation of floodplain creeks, rivers and wetlands which led to significant waterbird breeding and habitat recovery.

Climate models are indicating a neutral El Nino-Southern Oscillation for the second half of 2017 with warmer and drier than average conditions expected across Australia.

The Resource Availability Scenario (RAS) for 2017–18 is determined to be dry to moderate.

Water managers are planning to build on the preceding wet-year outcomes through the careful management of water to maintain habitat and support biological activity in 2017–18.

Further details on watering priorities for 2017–18 can be found in the Statement of annual watering priorities 2017–18 (PDF 1MB).

Highlights from 2016-17

Environmental water manager James Maguire said, during the 2016-17 season, the Murrumbidgee valley experienced very wet conditions and consequently very high inflows into the system.

‘Under these very wet conditions, Office of Environment and Heritage worked with the Commonwealth Environmental Water Office and the Murray Darling Basin Authority to deliver environmental water to the lower Murrumbidgee River reaches during the receding natural flood event. This was the largest managed delivery of environmental water yet undertaken in the Murrumbidgee valley’.

These flows were successful in limiting the impact of hypoxic water and maximising fish escape passage upstream through open weir gates.

Environmental water flows also supported and extended numerous colonial waterbird breeding events throughout the Murrumbidgee system. These waterbird breeding events collectively involved tens of thousands of ibis, spoonbills, egrets, night herons, cormorants, darters and pelicans.

Water delivered to the lower Murrumbidgee River helped maintain habitat availability for colonial-nesting waterbirds and native fish populations and increased connectivity between aquatic systems.

Numerous colonial waterbird rookeries – primarily ibis, herons, egrets and spoonbills were successfully maintained through watering at Nimmie Caira wetlands and Yanga National Park, while also providing habitat for southern bell frogs and Australasian bitterns. These flows also maintained critical refuge and floodplain habitats for fish, frogs, turtles, waterbirds and other aquatic species.

Managed watering events improved fringing river red gum condition and maintained critical refuge habitats for native fish, frogs and turtles at Western Lake and improved aquatic vegetation cover and diversity at several Coleambally Irrigation Area wetlands.