Australian in-water cleaning standards

We have developed draft Australian in-water cleaning (IWC) standards that specify the requirements for the removal of biofouling and cleaning of vessels that occur in-water – in Australian territorial seas.

The standards seek to manage the biosecurity and chemical contamination risks associated with in-water cleaning to an acceptable level.

Developing the standards

In Australia, in-water cleaning is currently managed in line with the Anti-fouling and in-water cleaning guidelines. The guidelines inform decisions about when to request in-water cleaning, and the conditions under which cleaning or treatment may be approved.

The Marine Pest Sectoral Committee reviewed the uptake and effectiveness of the guidelines in 2018. From this review, the committee recommended that an in-water cleaning standard be developed.

We worked with state and territory regulators to develop the Australian in-water cleaning standards to manage the biosecurity and chemical risks that may be caused by in-water cleaning. 

Australian regulators are receiving increasing numbers of requests to in-water clean. The standards will provide vessels with a way to manage their biofouling in an appropriate manner. 

In-water cleaning and treatment

In-water cleaning is the physical removal of biofouling and anti-fouling coating surface deposits from the submerged surfaces of vessels or other structures. For the purposes of the standards, ‘in-water’ refers to the parts of a vessel or movable structure that are either below the load line or normally submerged and/or are coated in anti-fouling coating. In-water cleaning includes hull grooming, propeller cleaning or polishing and cleaning of niche areas.

In-water cleaning may also include the treatment of biofouling to render it non-viable. Either in situ or after removal and capture.

Hull grooming

Hull grooming is proactive, regular and light cleaning of a vessel’s hull to remove slime or to prevent biofouling.

Hull grooming generally occurs on the flat surfaces of the hull that are prone to drag. It improves ship performance and efficiency. It also reduces environmental impact by reducing drag, fuel consumption, greenhouse gas emissions, and costs. Regular hull grooming may also eliminate the need for high intensity hull cleaning methods and increase the coating’s longevity.

Propeller cleaning and polishing

Propeller cleaning and polishing eliminates surface roughness of propellers to restore their propulsion efficiency.

Research

We commissioned studies to assess the biosecurity and chemical contaminant risks associated with in-water cleaning. These studies informed the evidence base for developing the Australian in-water cleaning standards.

Marine biosecurity

Vessel biofouling is a major pathway for the introduction of marine pests into Australian waters. In-water vessel cleaning and removal of biofouling is useful in minimising the biosecurity risk; however, biological waste must be captured to prevent exotic plants or animals establishing in Australia’s marine environment.

A review of minimum viable propagule sizes of key biofouling taxa was commissioned to:

• assess the potential for release of organisms during in-water cleaning
• inform the filtration level contained in the biosecurity standard.

Chemical contaminant risks

Most vessels are coated with an anti-fouling coating to prevent the growth of biofouling on their hulls and maintain vessel efficiency. Many anti-fouling coatings contain a biocide which is released into the seawater by one of several chemical mechanisms to deter marine growth.

Reports were commissioned to help the department better understand the potential chemical contaminant risks posed by in-water cleaning of anti-fouling coatings in Australian waters.

This report collates and evaluates available information on the chemical contaminant risks of in-water cleaning. It provides recommendations to the department on ways to manage these risks.

MAMPEC modelling of key Australian ports to predict environmental impacts of in-water cleaning discharge

This report includes a Marine Antifoulant Model for Predicting Environmental Concentrations (MAMPEC). It’s used to predict the amount of copper that may be released in key Australian ports under different cleaning scenarios.