The Department of Climate Change, Energy, the Environment and Water (DCCEEW) has published the ‘Guidance – Key environmental factors for offshore windfarm environmental impact assessment under the Environmental Protection and Biodiversity Conservation Act 1999 (Cth)’ (Guidance Document).


  • The Guidance Document identifies 13 key impacts which offshore wind proponents should consider when undertaking their environmental impact assessment (EIA) for the purposes of the Environment Protection and Biodiversity Conservation Act 1999 (Cth).
  • The Guidance Document provides high-level comments on assessing cumulative impacts, but flags that further specific guidance will be issued by DCCEEW in relation to assessing cumulative impacts of offshore wind projects.

There are 13 key impacts to be assessed by offshore wind proponents

The Guidance Document identifies 13 key impacts typically associated with offshore wind projects which should be considered when undertaking EIA. As the guidance is intended to apply nationally, not all of the impacts may be relevant to each project.

The 13 impacts are listed below:

  1. Underwater noise – mortality, injury and behavioural effects
  2. Turbine interactions – injury and mortality to birds and bats
  3. Electromagnetic fields
  4. Seabed disturbance – loss of/harm to benthic habitats
  5. Disturbance of underwater cultural heritage
  6. Physical presence – effects on hydrodynamics and sediment transport processes
  7. Physical presence – barrier effects and displacement of marine fauna
  8. Light emissions
  9. Vessel interactions – injury and mortality to marine fauna
  10. Invasive marine species
  11. Physical presence – socioeconomic: interference/displacement of existing use
  12. Physical presence – socioeconomic: seascapes and visual amenity
  13. Multiple impact pathways – Australian marine parks and their values

For each of the 13 key impacts identified, the Guidance Document provides information on:

  • Key receptors and protected matters (e.g. land and sea fauna and flora, cultural heritage, existing human uses (including views) and heritage values etc);
  • Key statutory documents, management principles and other resources that may be relevant to EIA of the impact;
  • Examples for how to define an acceptable level of impact against which to evaluate predicted impacts of a project;
  • Good practice management, including recommendations and/or potential requirements to minimise, monitor and mitigate potential impacts.

 Approach to assessing cumulative impacts

The Guidance Document notes that the process of declaring specific areas as suitable for offshore projects will likely result in having multiple projects in one area. The Guidance Document states that proponents should, where possible, take into account potential impacts of each project.

DCCEEW is still considering a policy approach to assessing cumulative impacts of offshore wind projects and has flagged that additional guidelines may be published in the future.

Monitoring data

As part of a broader suite of reforms to the EPBC Act, the Commonwealth is establishing Environment Information Australia, to identify and consolidate key environmental data to improve availability and accuracy.

The Guidance Document notes that while the reforms are ongoing, proponents of offshore wind projects are encouraged to voluntarily provide data and study outcomes to DCCEEW.

Next steps

A copy of the Guidance Document can be found here.

If you would like to understand what the Guidance means for your project or if would like to discuss offshore wind projects generally, please get in touch.

By Heidi Asten (Partner), Peter Briggs (Partner), Brigitte Rheinberger (Senior Associate) and Mayumi Martins (Graduate).

Heidi Asten
Heidi Asten
Partner, Melbourne
Peter Briggs
Peter Briggs
Partner, Sydney
+61 2 9225 5155
Brigitte Rheinberger
Brigitte Rheinberger
Senior Associate, Sydney
+61 2 9225 5750