Don’t fall foul of dust, debris and drips

Antifouling tins must be disposed of as hazardous waste

The Green Blue urges boaters to prevent antifoul scrapings, drips and spills from entering the water by placing a tarpaulin under the hull.

Kate Fortnam, The Green Blue Campaign Manager.

It Is that time of year again… when we turn our thoughts to annual winter maintenance and the chore of scrubbing down hulls and applying a new coat of antifoul for next season.

Antifouling paints are hazardous mixtures that prevent the build-up of marine organisms on vessel hulls. They work largely by releasing biocides into the water, preventing organisms from attaching themselves to the bottom of boats.

Whilst this is good for keeping the hull clean, improving efficiency through the water and preventing the spread of invasive non-native species, it does mean that some of the toxic ingredients leach into the water. Increased concentrations of copper that can sometimes be found in the sediment around lift out points in estuaries and rivers can find their way into the food chain causing a wide range of environmental problems and can also increase dredging costs.


Boat owners can play a vital role in preventing concentrated scrapings from entering the water by following best practice advice from The Green Blue, the joint environment initiative of the RYA and British Marine. A growing number of marinas, clubs and boatyards have installed wash-down facilities that 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.

If you wash your hull off on a slipway, place a length of rope across the slope to catch larger paint particles that can be swept up and put in the hazardous waste bin. If you use scrubbing piles, only scrub off the fouling and not the residue paint – be careful not to let debris enter the water. When sanding, use a dustless vacuum sander to reduce toxic dust from the paint and antifouling coatings.

Most marine facilities would prefer not to have their sites covered with blue patches and do not want loose material entering the water or nearby surface water drains. Tarpaulins are an easy and inexpensive solution when sanding or scrubbing and to catch drips and spills when painting. It is also important to note that antifouling tins as well as topside paints, varnishes and solvents have to be disposed of as hazardous waste, as do used brushes, rollers and trays.

A tarpaulin can be used to collect much of the paint residue.


Take advice from your chandlery on the correct type of antifoul for your location and use, preferably with the lowest levels of biocides and copper suitable for your needs. Take a look at different technologies, copper free antifouling or alternative hull paints such as vinyl, silicone or Teflon or even consider an ultrasonic system.

And do not forget, always follow the paint manufacturer recommendations and wear the recommended Personal Protective Equipment to minimise skin contact and avoid breathing dust.

Kate Fortnam, Campaign Manager for The Green Blue, says: “If a pressure-washer is used to remove fouling, it is highly likely that the water run-off will be contaminated with paint and this could enter the marina water if it is not contained.  A permanent bund, tarpaulin or heavy rope lain across the hard standing can be used to collect much of the paint residue.

“Once the hull is clean, this waste can be collected and disposed of in an appropriate way. Boat owners can also play a vital role in preventing concentrated scrapings from entering the water by choosing a marine facility that uses a washdown system to capture run off.”

To find out more about antifouling best practice, visit the RYA’s Environment hub at For top tips on safeguarding our inland and coastal waters, visit The site is packed with practical advice, case studies and information on green products to help you save money and protect water quality and habitats.


The Green Blue is the joint environment initiative of the RYA and British Marine that helps boat users, boating businesses, clubs and training centres to reduce their impact on coastal and inland waters to keep them in great shape for now and the future. The Green Blue raises awareness, supports practical projects, runs bespoke outreach activities and offers easy to follow advice to make boating in the UK as sustainable as possible. Visit to find out more.