Managing biofouling

Biofouling is the growth of marine plants and animals on the submerged parts of a vessel or infrastructure including the:

  • hull
  • propellers
  • anchors
  • niche areas
  • fishing gear
  • port infrastructure
  • navigation equipment.

Vessel biofouling is a major pathway for the introduction of exotic species into Australian waters.

The infrastructure that supports the operation of vessels (for example ports, boat harbours, marinas, slipways, recreational boating mooring areas and fishing ports/bases) provide hotspots for the introduction and spread of marine pests from both international and domestic vessels.

Marine facility owners, operators and their personnel can reduce and manage the risk of marine pest introduction, establishment and spread by following best practice strategies for managing and mitigating impact from biofouling at their facilities and operations.

Vessel owners can reduce the risk of spread of marine pests by incorporating practices that minimise the build-up of biofouling into routine cleaning and maintenance programs.

National biofouling management guidance has been developed for a range of vessel types.

Biofouling guidelines

The national Anti-fouling and in-water cleaning guidelines apply to vessels and moveable structures such as:

  • oil and other exploration rigs
  • floating dry docks
  • pontoons
  • aquaculture installations
  • navigational structures.

In-water cleaning

In-water cleaning of vessels, including immersible equipment, can reduce the likelihood of invasive marine species (IMS) introduction and spread. Maintaining a clean hull can also assist in preserving vessel performance. If appropriate in-water cleaning practices are not employed, however, they can result in the release of IMS into the marine environment. Overly abrasive cleaning methods can also damage anti-fouling coatings and lead to the release of contaminants into Victorian waters.

Removal of vessels from the water and cleaning on land is the preferred method of treating biofouling and should be used whenever possible. However, when dry docking is not possible, in-water cleaning may be recommended in exceptional circumstances.

Wherever possible, in-water cleaning activities should only occur using systems for which there is high-quality evidence, based on independent testing, that they are capable of removing, capturing and containing biofouling and contaminants.

In-water cleaning requests

Vessel operators must make every attempt to clean vessels outside of Victorian coastal waters.

Where this is not possible, any request to undertake in-water cleaning activities should be made to or forwarded to Agriculture Victoria in the Department of Energy, Environment and Climate Action, as the lead for marine biosecurity in Victoria, as soon as practicable. Agriculture Victoria will liaise with the Environment Protection Authority to ensure contaminant risks are addressed. Requests must be made at least 10 business days prior to the intended clean. Requests should be sent to

All requests to undertake in-water cleaning must be accompanied by the following:

1.  Detailed information regarding vessel history including:

  • recent IMS inspection or in-water cleaning documentation
  • dry dock reports
  • last ports of call information
  • information on anti-fouling coating condition

2.  Risk assessment of the vessel’s biofouling management. The preferred assessment tool is the online Vessel-Check portal. Information that will be collected on the Vessel-Check portal will include, but is not limited to:

  • biofouling management plan
  • biofouling record book
  • anti-fouling documentation

Provision of a desk top risk assessment by a qualified biofouling inspector may be acceptable.

3.  Detailed information regarding the proposed cleaning process including:

  • cleaning method
  • capture method
  • contractor
  • biofouling inspector

Applicants must be able to demonstrate that:

  • The antifouling coating will remain unaffected.
  • All cleaned surfaces are free from visible macro-fouling or fouling has been rendered non-viable.
  • All debris greater than 50μm will be captured.
  • There is no possibility of material escaping into the environment whether by mechanical failure or inappropriate cleaning method.
  • Collected material will not be released into the environment unless it has been rendered non-viable. Hard waste or macro-fouling must not be returned to the environment.

Final approval for in-water cleaning activities in Victoria will only be given by the Harbour Master of the port in which the cleaning will occur on advice from Agriculture Victoria.

Australian in-water cleaning standard

The Australian Government is developing a national in-water cleaning standard for vessels. The standard will outline how to manage the potential biosecurity and environmental risks of in-water cleaning and treatments.

Victoria has been involved in the development of the national standard which aims to provide national consistency for in-water cleaning activities.

If you are considering undertaking in-water cleaning of a vessel in Victoria, you must contact us on 136 186 or email before starting any works.

Page last updated: 22 Apr 2024