In-water cleaning (IWC) of ship hulls and niches is an essential part of biofouling management.

In the Baltic Sea Region (BSR), granting of permissions for IWC is in the responsibility of national or even local administrations, depending on the country. One outcome of the COMPLETE project was that there is no common understanding of the regulation of IWC and no common basis for the granting of permissions. Thus, as part of the COMPLETE PLUS project and as important addition to the proposed HELCOM Biofouling Management Roadmap, BSH (Federal Maritime and Hydrographic Agency) developed a proposal for a harmonized risk assessment procedure as basis for permissions of in-water cleaning (IWC) of ships by taking into account three relevant environmental impacts of IWC:

• Risk of species introduction (biosecurity risk)
• Risk of biocide input
• Risk of particle input

The risk assessment bases on experiences from the COMPLETE project but also on experiments performed in other research studies from all over the world. Administrations and Ports who are the main bodies responsible for IWC as well as transport agencies, EPAs, scientific institutes and diving companies from all interested Baltic Sea countries have been involved in the development by inviting them to provide input and discuss the applicability in their respective locations at several national and international meetings. The resulting options for consideration of IWC permissions of ships in the BSR are visualized in a flow chart aiming to create the decision process more transparent for both, the applicants and the responsible authorities. In the resulting risk assessment outcomes, IWC may be permitted (1) if the fouling material is captured and filtered, (2) if the fouling material is captured and filtered plus explicitly filtrating biocides and/ or a prior chemical risk assessment, or (3) the IWC is not recommended or even prohibited and the ship must be cleaned in dry-dock.

All aspects and ratings included in this proposal of a risk assessment as basis for the permission of IWC should be revisited as soon as the revision of the IMO Biofouling Guidelines has been finalized. Details might differ from what is going to be agreed internationally. It is therefore also be mentioned that the terms used and the definitions might differ from those used in the future Biofouling Guidelines and thus, need to be adopted accordingly.

For more information on the proposal of a risk assessment as basis for permissions of IWC in the BSR, see the Risk assessment of in-water cleaning (IWC) of ships in the Baltic Sea Region published on the COMPLETE PLUS website.

Text: Nicole Heibeck and Katja Broeg (Federal Maritime and Hydrographic Agency, Hamburg, Germany)

Flow chart of recommended IWC decisions for ships in the BSR: Cleaning could be allowed with (1) capture and filtration (yellow), (2) capture and filtration including biocides and/or chemical risk assessment beforehand (orange) or IWC should not be permitted (red).