Skip to main content Skip to main navigation Skip to search

Queensland and NSW floods 2022

Visit recovery.gov.au to see what help is available.

Close
Home

Top navigation main

  • News & media
  • Jobs
  • Ministers
  • Contact us
Main menu

AWE Main

  • Climate change
    Climate change Driving climate action, science and innovation so we are ready for the future.
    • Climate science and adaptation
    • Australia's climate change strategies
    • Emissions reduction
    • Emissions reporting
    • International commitments
    • Climate Active
    • Climate change publications and data
    • Australian Greenhouse Emissions Information System (AGEIS)
    Stronger action on climate change

    Stronger action on climate change

    See how the Australian Government is committed to taking more ambitious action on climate change.

    Find out more

  • Energy
    Energy Building a secure and sustainable energy system for all Australians.
    • Energy policy in Australia
    • Energy ministers
    • Renewable energy
    • Energy publications
    • energy.gov.au
    • Energy Rating
    • Commercial Building Disclosure Program
    • Nationwide House Energy Rating Scheme (NatHERS)
    • Your Home
    Save on your winter energy bills

    Save on your winter energy bills

    Making energy-smart choices can reduce winter’s impact on your wallet.

    Find out more

  • Environment
    Environment Improving stewardship and sustainable management of Australia’s environment.
    • Bushfire recovery
    • Climate change and the environment
    • Biodiversity
    • EPBC Act
    • Environmental information and data
    • International activities
    • Invasive species
    • Land
    • Marine
    • Partnerships
    • Protection
    • Report a breach of environment law
    • Threatened species & ecological communities
    • Waste and recycling
    • Wildlife trade
    Waste exports

    New waste plastic export regulations

    The Australian Government works to reduce waste plastics and turn that waste into valuable products.

    Find out more

  • Water
    Water Improving the sustainable management of Australia’s water supply for industry, the environment and communities.
    • Coal, Coal seam gas (CSG) and water
    • Commonwealth Environmental Water Office
    • Water policy and resources
    • Wetlands
    Water matters

    Water Matters

    Keep up with the latest news on the department's work in managing Australia's water resources.

    Read the latest edition here

  • Parks and heritage
    Parks and heritage Managing Australia’s iconic national parks, historic places and living landscapes.
    • Australian Marine Parks
    • Australian National Botanic Gardens
    • Booderee National Park
    • Kakadu National Park
    • Christmas Island National Park
    • National parks
    • Norfolk Island National Park
    • Heritage
    • Pulu Keeling National Park
    • The Great Barrier Reef
    • Uluṟu-Kata Tjuṯa National Park
    The reef

    Great Barrier Reef

    Australia is protecting and conserving this World Heritage Area.

    Find out more

  • Science and research
    Science and research Undertaking research and collecting data to support informed decisions and policies.
    • Climate change
    • Australia's biological resources
    • National Environmental Science Program (NESP)
    • Our science strategy
    • Australian Biological Resource Study (ABRS)
    • State of the Environment (SoE) reporting
    • Bird and bat banding
    • Supervising Scientist
    Our climate is changing

    Our climate is changing

    Find out more about how climate science helps Australians with the impacts of climate change.

    Find out more

  • About us
    About us We lead Australia’s response to climate change and sustainable energy use, and protect our environment, heritage and water.
    • Accountability and reporting
    • Assistance, grants and tenders
    • Contact us
    • Fees and charges
    • News and media
    • Our commitment to you
    • People and jobs
    • Publications
    • What we do
    • Who we are
    Our department has changed

    Our department has changed

    Learn more about our roles and responsibilities.

    Find out more

  • Online services
    Online services We do business with you using online platforms. This makes it easier for you to meet your legal requirements.
Department of Climate Change, Energy, Enviroment and Water

Breadcrumb

  1. Home
  2. Water
  3. Commonwealth Environmental Water Office
  4. Commonwealth Environmental Water Office Publications and resources
  5. MER Lower Murray 2019-20 Annual Reports

Sidebar first - EN - Water

  • Publications and resources
    • Events
      • Fish, Feathers and Flows
      • Northern Fish Flow Drop-In Sessions
      • Webinar: A conversation with the CEWH
    • Freedom of Information

MER Lower Murray 2019-20 Annual Reports

2021

A report prepared for the Commonwealth Environmental Water Office by the South Australian Research and Development Institute, Aquatic Sciences and the Lower Murray Selected Area team

Download
MER Lower Murray 2019-20 Summary Report (PDF 4.5MB)
MER Lower Murray 2019-20 Summary Report (DOC 4.8MB)
MER Lower Murray 2019-20 Technical Report (PDF 10.2MB)
MER Lower Murray 2019-20 Technical Report (DOC 35.5MB)

About the document

The summary and technical reports present the 2019-20 results from the Commonwealth Environmental Water Office’s (CEWO) Monitoring, Evaluation and Research (MER) Project (Flow-MER) in the Lower Murray River. Monitoring and research activities in 2019-20 included the monitoring of Hydrology, Stream Metabolism and Water Quality, Fish Community, Hydraulic Regime, Matter Transport and Coorong Habitat, Littoral Vegetation Diversity and Productivity, Microinvertebrate Assemblage, Murray Cod Recruitment, Flow-cued Spawning Fish Recruitment and Lamprey Migration. Both reports evaluate the contribution that water for the environment has made to environmental outcomes in 2019-20 in the Lower Murray River, building on the monitoring and evaluation undertaken from 2014-2019.

Key findings include:

  • Increased flowing habitat: The length of river with ‘flowing water’ habitat (greater than 0.3 metres per second) increased by 10% (for at least a four-week period).
  • During spring–summer, increased water mixing and oxygen exchange (due to more flowing water) decreased the likelihood of low oxygen levels (e.g. <5 milligrams per litre, mg/L). Aquatic animals generally need oxygen levels above 5 mg/L, particularly during spring–summer, which is the main reproductive season of many species.
  • Increased Murray cod recruitment, potentially supported by the increased extent of their favourable (flowing water) habitat during the spawning/early larval period, and increased larval food resources.
  • Increased water level variability: Water for the environment, in combination with weir pool manipulations, increased water level variability. Subsequent inundation of the riverbank increased the diversity of native vegetation on the bank.
  • In the river channel, food production marginally increased (by ~1%) due to changes in water level and channel width. Nevertheless, the amount (density) and variety (diversity) of microinvertebrates increased due to water for the environment, likely through inputs from off-channel or upstream environments as a result of increased lateral and longitudinal connectivity.
  • Spawning of golden perch occurred in the Lower Murray, but there was negligible ‘recruitment’ and diminished golden perch population resilience. The current fish community in the Lower Murray is characteristic of low river flows.
  • Maintained connectivity between the river, Coorong estuary and Southern Ocean. Flows through the barrages to the Coorong were continuous throughout the year and comprised of 100% Commonwealth environmental water.
  • Barrage flows during winter and spring facilitated connectivity and promoted lamprey migration. Migration between fresh and saltwater habitats is necessary for lamprey to successfully reproduce.
  • Water for the environment substantially increased salt export out of the Basin (by 623,999 tonnes), reduced salt import into the Coorong (by ~5.5 million tonnes 2017-20) and reduced salinity concentrations in the Coorong, which maintained estuarine habitats (e.g. for fish and aquatic vegetation) in the Coorong. This was crucial in maintaining species diversity and ecosystem functions.

The information from the Lower Murray MER reports is being combined with six other MER Project Selected Areas to provide a Basin-scale evaluation (led by the Commonwealth Scientific and Industrial Research Organisation (CSIRO)) of the outcomes of water for the environment. Recommendations and limitations outlined in the Flow-MER Program are used to inform future management of water for the environment, using the best available scientific knowledge.

Further information:

  • Monitoring - Lower Murray-Darling
Thanks for your feedback.
Thanks! Your feedback has been submitted.

We aren't able to respond to your individual comments or questions.
To contact us directly phone us or submit an online inquiry

CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.

Please verify that you are not a robot.

Skip

Footer

  • Contact us
  • Accessibility
  • Disclaimer
  • Privacy
  • FOI
Last updated: 03 October 2021

© Department of Climate Change, Energy, the Environment and Water

We acknowledge the Traditional Owners of country throughout Australia and recognise their continuing connection to land, waters and culture. We pay our respects to their Elders past, present and emerging.