Testing framework and performance standards for In-water removal or treatment of vessel biofouling

30 Aug 2017
It is often not practical to remove large vessels from the water to clean or treat the biofouling that has accumulated on their hull. In-water removal of biofouling can create additional environmental risks through release of organisms and contaminants dislodged by the cleaning process. This project reviewed available technologies for in-water cleaning and defined performance standards and a testing framework for evaluating their efficacy.
Ectopleura crocea as vessl biofouling
[Image: Chris Woods, NIWA]

In-water cleaning or treatment systems can be used to manage biofouling in the interval between dry-docking a vessel (often up to 5 years). However, use of these systems also carries some residual environmental risk that must be managed. This can include release of viable non-native organisms and contaminants from the vessel's antifouling coatings into the surrounding environment.

This project reviewed the range of technologies that are currently available for in-water cleaning and some that are still in development. The review informed the development of a testing framework and standards for evaluating the performance of in-water systems to obtain approval from the Ministry for Primary Industries (MPI) for use in New Zealand. The testing framework was developed for three generic types of systems:

  • removal (“cleaning”) of vessel biofouling,
  • treatment of vessel biofouling and
  • filtration or treatment of removed waste.

It covered manual and mechanical cleaning methods, surface treatments and shrouding technologies. The framework requires systems to be tested on biofouling present on actual vessels and for the outcomes of the testing to be assessed against specified performance standards. Tests should be realistic simulations of the intended use of the system on a vessel. The testing framework will allow consenting authorities (both government and non-government) to make informed decisions regarding the biosecurity risk of in-water systems for removal or treatment of vessel biofouling.

VesselbiofoulingChrisWoods

[Image: Chris Woods, NIWA]

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Key Contacts

Chris Woods Graeme Inglis Eugene Georgiades
Principal Investigator Principal Investigator Technical Liaison
NIWA NIWA Ministry for Primary Industries
chris.woods@niwa.co.nz graeme.inglis@niwa.co.nz Eugene.Georgiades@mpi.govt.nz