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Department of Transport and Main Roads


Dredging is a vital part of operating a safe and efficient port.

Dredging management

Dredging management is a form of sustainable infrastructure asset management involving maintaining (maintenance dredging) and enhancement (capital dredging) of dredged channels, swing basins and berth pockets.

Dredging and disposal

Applications for dredging and disposal must undergo a comprehensive environmental assessment.

Read more about dredging in Queensland ports

Capital dredging

Capital dredging is the removal and relocation of natural previously undisturbed seabed to increase water depth for shipping channels, swing basins and berth pockets.

Under the Sustainable Ports Development Act 2015, it is a condition of approvals for any capital dredging in the Great Barrier Reef World Heritage Area that dredge material must be beneficially reused for example, for land reclamation.

Maintenance dredging

Maintenance dredging is the removal of mobile natural sediments that settle into existing channels, basins and berth pockets to ensure continued safe navigational movement of vessels and port operations. 

Regulatory framework

There are international, federal and state legislation, policies and guidelines that cover dredging and disposal at sea.

Australia is a signatory to the 1996 Protocol to the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter, 1972 (London Protocol).

The London Protocol is a global convention that aims to protect and preserve the marine environment from all sources of pollution and take effective measures to prevent, reduce and where practicable eliminate pollution caused by disposal or incineration of wastes at sea.

All dredging activities in Queensland are managed under both State and Commonwealth legislation. The application of the State and Commonwealth legislation varies depending on specific legislative requirements applicable at each port.

There are legislative requirements that apply specifically to the activity of dredging, and different regulatory instruments applying to the activity of placing dredge material at sea.  

The key Commonwealth Acts relating to the regulation of dredging and dredge material disposal at sea include:

  • Environment Protection (Sea Dumping) Act 1981 (Sea Dumping Act) which implements Australia’s obligations under the London Protocol to prevent marine pollution by dumping of wastes and other matter.
  • Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) provides a legal framework to protect and manage nationally and internationally important flora, fauna, ecological communities and heritage places (matters of national environmental significance).
  • Great Barrier Reef Marine Park Act 1975 (GBRMP Act) provides for the long-term protection and conservation of the environment, biodiversity and heritage values of the Great Barrier Reef Region. Applications for dredging and disposal of dredge material within the Great Barrier Reef Marine Park must undergo a comprehensive environmental assessment.
  • The Great Barrier Reef Marine Park Regulations 1983 bans the disposal of dredge material in the Great Barrier Reef Marine Park from capital dredging projects such as port developments.  

The National Assessment Guidelines for Dredging 2009 (NAGD) seeks to provide clear, consistent standards and criteria for assessment of dredged material, and to facilitate better decision-making by regulators, by improving the quality of information on which assessments are based. The NAGD are actively used by all ports and regulators, and form the basis of the approvals process. It must be addressed as part of an application under the Sea Dumping Act. 

The NAGD sets out the framework for the environmental impact assessment and permitting of the ocean disposal of dredged material. The framework includes:

  • evaluating alternatives to ocean disposal
  • assessing loading and disposal sites
  • assessing potential impacts on the marine environment and other users
  • determining management and monitoring requirements.

The intention of the NAGD is to provide greater certainty about the assessment and permitting process behind dredging approval applications. Although not a legislative act, the NAGD provides guidance for all dredging activities undertaken in Australian Waters. The NAGD should be read in conjunction with the Sea Dumping Act and its Regulations, the EPBC Act, the GBRMP Act and Australia’s international obligations outlined in the London Protocol. 

Queensland Government legislation applies for dredging that occurs within State Waters. As all ports within the GBRWHA also reside within Queensland State Waters, Queensland State legislative acts are applicable to all GBRWHA port dredging operations. The primary state legislation that may apply includes:

  • Transport Infrastructure Act 1994 requires Queensland ports to undertake maintenance dredging to fulfil their requirement to provide and operate effective and efficient port facilities and services.
  • Marine Parks Act 2004 supports the creation of a comprehensive and balanced zoning system within the GBR Coast Marine Park, providing protection of the GBR’s unique biodiversity, while continuing to provide opportunities for the use of and access to the marine park.
  • Sustainable Ports Development Act 2015 provides for the protection of the GBRWHA through managing port-related development in and adjacent to the area. Master planning is required for the priority ports of Gladstone, Abbot Point, Townsville and Hay Point/Mackay that establishes a long-term vision for the future development of the priority ports consistent with the principles of ecologically sustainable development.
  • Coastal Protection and Management Act 1995 provides for the protection, conservation, rehabilitation and management of Queensland’s coastal zone, including its resources and biological diversity.
  • Environmental Protection Act 1994 provides for the protection of Queensland’s environment through an integrated management program that is consistent with ecologically sustainable development.
  • Fisheries Act 1994 sets out Queensland’s responsibilities for the economically viable, socially acceptable and ecologically sustainable development of Queensland’s fisheries resources.
  • Planning Act 2016 provides for land use planning and development assessment to facilitate the achievement of ecological sustainability.   

Regulators for dredging

A dredging campaign may involve at least one, or all of the relevant activities in each jurisdiction, requiring approvals from at least one, or up to all regulators, for example:

Dredging management

The port industry incorporates environmental risk assessment and management into the planning and execution of dredging activities. Read more about dredging management.

Sediments and dredging at ports

The Reef 2050 Long-Term Sustainability Plan required the delivery of Water Quality Action 17 (WQA17) to understand port sediment characteristics and risks in relation to dredging at Queensland ports. Queensland Ports Association delivered WQA17.

Further information

Last updated 14 May 2024