News
22-01-2008
Antifouling - the future?
Discussions about the viability of non-biocide antifouling took a step forward last week at the Collins Stewart London Boatshow.
The Green Blue convened a seminar in partnership with the Broads Authority. Broads Chief Executive John Packman chaired proceedings. David Lewin, of Flag Paints Ltd, spoke on behalf of paint manufacturers.
Research has found that the banned antifouling additive tributyltin (TBT), outlawed for use on small craft in 1987, still exists in substantial quantities especially in boat yards. The Broads Authority presented the research by Dan Hoare Ph.D., a Conservation Officer at the Broads Authority, who spent 3 years studying the legacy of residual TBT contamination on The Broads’ ecosystem.
Turning to prevention, the meeting heard from Dominic Hutton, an M.Sc. student at Kings College London. He studied the concentration of copper entering Lymington River from pressure washing boats, discovering a clear link between high levels of copper in the water and the boat wash down area. This quickly dispersed with tidal action and as time passed, but would have been prevented altogether by a closed loop system. His work was sponsored by the Green Blue as part of its mission to increase the body of available knowledge in this area. The Green Blue’s Katherine Rowberry and Nigel Dark of the Broads Authority, then outlined how closed loop boat pressure washing systems work in practice.
John Packman said: 'The Broads Authority has a long history of supporting research and restoration of The Broads. We hope that this information will alert boat owners to consider biocide-free antifouling, or to minimise the use of antifouling by only painting around the waterline. We are working with the Broads’ boat industry to find ways of minimising their impacts on these special waterways. This includes supporting systems such as closed loop pressure washing.’
The Green Blue Research Manager Anna Wyse commented 'It appears that keeping residual antifouling from boat maintenance and pressure washing out of the water is an effective way of reducing biocides in marine sediments. The Green Blue is today publishing a Fact Sheet on closed loop antifouling systems. We hope to see these grow in popularity in the UK. I would like to see the Government provide a grants scheme to marinas and boatyards to assist them in installing these systems.’
She continued 'The next step is to encourage the use of non-biocide antifouling. The technology for these coatings may have some way to go before it matches the effectiveness of copper based antifouling, however it is improving all the time.'
In general, antifouling paints work by creating a biocide barrier which prevents biofouling i.e. organisms attaching themselves to the hull. Biofouling slows the boat, reduces manoeuvrability and increases fuel consumption. However, if present in sufficient quantities, the chemicals could have an impact on aquatic life including water fleas, dragonfly and fish larvae.
A copy of all the presentations are available to download below.
» Biofouling in the Broads, Andrea Kelly, Conservation Officer, The Broads Authority
» Fate of copper from boat washdown, Dominic Hutton, MSc Kings College London
» Best practice advice when renewing antifouling, Katherine Rowberry, The Green Blue
