Environmental good practice and antifouling need not be the opposite ends of the spectrum. But do you know how to choose the right antifouling, apply the right quantities, and remove and dispose of the old coatings?
Biocidal antifouling paints are hazardous mixtures that function by preventing the build-up of marine organisms on the hulls of commercial ships and pleasure craft of all sizes. Antifouling paints work largely by releasing biocides into the water, thus preventing organisms from attaching themselves to the bottom of boats.
Whilst antifouling does a great job of keeping our hulls clean, and even has some environmental benefits such as improving fuel efficiency and preventing the spread of invasive non-native species, it is toxic to aquatic life. Since the banning of TBT in 1987, most antifouls are now copper or zinc based. Some of the compounds found in these antifouls can accumulate in marine organisms, and can find their way into marine wildlife further up the food chain.
The majority of copper in antifouling enters the marine environment through leaching. However concentrated amounts do enter the marine environment during the removal of antifouling paint, which occurs mostly by water blasting or mechanical scraping, and can form concentrated deposits in the sediments around marinas and in river beds.
Boat owners can play a vital role in preventing concentrated scrapings from entering the water by choosing a marine facility that uses a washdown system that captures run off, and by following the best practice advice available from The Green Blue. A growing number of marinas, clubs and boatyards have installed washdown facilities which collect residues from your boat instead of letting it run back into the water. Some also recycle the wastewater for re-use, preventing pollution and saving water costs.
Some best practice advice includes: