Map of the Lachlan catchment showing waterways, wetlands and locations of water for the environment deliveries made in 2019–20.

The delivery of NSW and Commonwealth water for the environment in the Lachlan catchment during 2019–20 focused on avoiding irreversible impacts to priority animal and plant species by building resilience and condition into high priority ecological targets throughout winter and spring.

The watering aims identified in the Lachlan Catchment Annual Environmental Watering Priorities for the 2019–20 water year were largely implemented as proposed under very dry to dry conditions.

This bar chart and table provide a summary of 31,934 megalitres of water for the environment use in the Lachlan catchment during the 2019–20 watering year. Volumes are indicative only. Watering event numbers in the bar chart and table relate to location numbers marked on the map.

Bar chart showing water delivery to the Lachlan catchment in the 2019-20 water year.

Watering event number Location Outcomes Start
date
Finish
date
1 Booberoi Creek
Native fish icon 01 Jul 2019 31 Aug 2019
2 Kiagarthur Waterbird icon 24 Jul 2019 15 Dec 2019
3 Merrowie Creek to Murphys Lake
Waterbird icon 24 Jul 2019 15 Dec 2019
4 Merrimajeel Creek to Murrumbidgil Swamp
Native vegetation icon 11 Aug 2019 08 Oct 2019
5 Burrawang West Yarrabandai
Connectivity and water flow icon 13 Aug 2019 04 Dec 2019
6 Spring pulse: connectivity
Connectivity and water flow iconNative vegetation icon 17 Sep 2019 10 Oct 2019
7 Booberoi spring pulse
Native vegetation iconNative fish icon 01 Oct 2019 30 Mar 2020
8 Noonamah
Waterbird icon 28 Oct 2019 10 Jun 2020
Notes: NSW = NSW licensed environmental water; CEW = Commonwealth licensed environmental water.

Monitoring of the delivery of water for environment in 2019–20 by the Department of Planning, Industry and Environment – Energy, Environment and Science (DPIE – EES) Water for the Environment Team and partners indicated that a number of ecological outcomes were achieved in multiple locations across the Lachlan catchment.

During spring 2019, a whole-of-system multi-site flow in the Lachlan River provided:

  • food and habitat for native fish
  • critical foraging and roosting habitats for a diversity of waterbirds
  • increased productivity in the river
  • support for native vegetation communities.

A diversity of waterbirds including threatened species such as freckled duck, blue-billed duck and brolga, as well as migratory shorebirds such as Latham’s Snipe, common greenshank, sharp-tailed sandpiper and resident wader species, were detected at multiple sites in the mid- and lower-Lachlan. Smaller targeted events to wetlands such as Kiagarthur, Yarrabandai and Noonamah provided critical refuge for a range of waterbird species in an otherwise dry landscape. Due to the very dry conditions the abundance of waterbirds was lower compared with wetter years.

Several additional flows were delivered in the Merrowie, Merrimajeel and Booberoi creeks for vegetation, waterbird and native fish outcomes including strategic drought refuge for threatened eel-tailed catfish and Murray cod.

Water for the environment held in the Brewster weir pool helped provide critical habitat for the Lachlan’s last known population of olive perchlet, a small-bodied native fish which is listed as endangered in NSW.

Low flows below Booligal were supplemented to avoid the river breaking up into isolated pools, mitigate against poor water quality conditions and reduce the risk of fish kills. These outcomes achieved the key planned actions proposed for the 2019–20 water year.

Lake Cargelligo, Australian shelduck and black-winged stilts.

Thousands of birds found refuge from drought in Lachlan wetlands during 2019–20, thanks to NSW and Commonwealth water for the environment.

Three threatened species – freckled ducks, blue-billed ducks and brolga – were among thousands of birds spotted in wetland surveys over spring and summer.

Water for the environment was delivered to 9 separate wetland sites at different times during the season, supporting habitat for a diverse range of waterbirds.

As well as threatened ducks, Australian shelduck, pink-eared duck, black swan, glossy ibis, red-necked avocet, pied cormorant, Australasian darter and Eurasian coot were sighted.

Migratory shorebirds were also seen in the wetlands feeding in preparation for their migration to the northern hemisphere.

Water lasted on some sites from 4 to 8 months, up until April in many places. One deep wetland in the Cumbung Swamp will likely retain water to provide ongoing drought refuge.

Watering events were conducted in partnership with state and federal government agencies, private landowners and local field ornithologists.