In the Lachlan catchment, water for the environment was used to provide a series of flows throughout the year targeting the full length of the Lachlan River, including the Great Cumbung Swamp, the Booberoi Creek anabranch system, Lake Brewster outflow wetlands, and several small private wetland waterings. This:
- provided benefits for native fish populations, including the first pre-emptive use of the water quality allowance to avoid fish kills during record heat and blue-green algal outbreaks
- delivered pulses of water into anabranch creeks, increasing connectivity
- supported successful wetland plant (aquatic macrophyte) establishment
- supported riparian and wetland vegetation in the lower Lachlan, including core reed beds in the Great Cumbung Swamp
- provided roosting and foraging habitats for water birds in the lower Lachlan
- stimulated the aquatic food web along the length of the Lachlan River
- provided opportunities to partner with the mid-Lachlan Aboriginal community and Ngiyampaa Nation to support and access the cultural values and practices of Booberoi Creek.
The Bureau of Meteorology reported 2018–19 as Australia’s hottest summer on record. In the Lachlan catchment, low rainfall accompanied the record heat of summer, with no notable inflow into Wyangala Dam and no new available water determination since August 2017. Water used was carried over in accounts from the 2016 flooding, with Wyangala Dam starting the water year at around 60% and finishing at 29%.