About the document
This report is the product of the first year of monitoring and evaluation in the Murrumbidgee River under the Commonwealth Environmental Water Office’s Long Term Intervention Monitoring (LTIM) Project. The report evaluates the contribution of Commonwealth environmental water to environmental outcomes in 2014-15, complementing previous short term monitoring and evaluation work undertaken in 2012-13 and 2013-14.
The Murrumbidgee River LTIM Project identified a number of key environmental outcomes achieved through the use of environmental water in 2014-15, including:
- Spawning of at least seven native fish species including golden perch, silver perch (critically endangered under EPBC Act), Murray cod (vulnerable under EPBC Act) and trout cod (endangered under EPBC Act).
- Breeding and recruitment of southern bell frog (vulnerable under EPBC Act) in the Nimmie-Caira.
- Germination, growth and flowering of aquatic and semi-aquatic vegetation at all sites receiving water.
- First recording of spiny mudgrass and the inland banjo frog since before 2010, following repeated inundation of Yarradda Lagoon in the mid-Murrumbidgee wetlands.
- The development of productive wetland ecosystems capable of supporting diverse food webs, including algae and microinvertebrates, which support biota at higher trophic levels such as fish and waterbirds.
- Return flows in the Lowbidgee floodplain (release of water from the floodplain to the main channel) contributed to improvements in water quality across the river red gum wetlands, reducing the risks of future hypoxic blackwater events.
The report is presented in three parts: an executive summary; a non-technical synthesis report; and technical appendices which provide detailed methods, analyses and results for each indicator.
This report is the first of five to be produced for the Murrumbidgee River Selected Area under the LTIM Project, with monitoring and evaluation being undertaken from 2014-15 to 2018-19. The data and evaluation report from this project are being combined with those from six other LTIM Project Selected Areas within the Basin, as part of a Basin-scale evaluation of the contribution of Commonwealth environmental water to the environmental objectives of the Basin Plan being led by the Murray-Darling Freshwater Research Centre.
In addition to assisting the Office to demonstrate environmental outcomes, the LTIM Project is designed to allow adaptive management of the water holdings. As such, identified outcomes and limitations are used to inform environmental watering in future years leveraging the best available, contemporary scientific knowledge.
Redressing environmental decline that has occurred over decades is going to take us some time – it will be at least ten years before we can show lasting change and improvements to the health of the rivers, floodplains and wetlands, consistent with the long-term targets of the Murray-Darling Basin Authority’s Basin-wide environmental watering strategy.