Practical Boat Owner – May 2018

12 Practical Boat Owner • http://www.pbo.co.uk

Fouling away

Scraping, sanding and pressure-washing boat

hulls creates toxic effluent that is being

dumped, untreated, into the sea every day of

the year. Huw Williams is taking a stand

A

blue stream is making its
way from the hardstanding
and across the footpath.
When it reaches the
grassed area, it backs up
a little, before seeping its way through
the soil and eventually into the marina
basin. Once it reaches the water it
blossoms into a circular shape about
4m in diameter. It actually looks quite
pretty and, about 20m away, another
stream, this time pink, is making
similar progress.
After about 30 minutes the colourful
spectacle in the marina is over, although if
you want to see it again you could visit
here tomorrow, or you could visit the
marina on the other side of the harbour, or
anywhere in the country really, because
it’s a very common occurrence.
In a few days, the grass will have died
and small mammals and insects will have

walked through the residue and absorbed

the toxins through their skin. The

hardstanding and footpath will remain

stained for months.

We can’t see it, but below the water’s

surface the toxic chemicals have started

to destroy marine life. No wonder the

water here is a vile soup.

Back on land the yacht owner looks at

his scraped and sanded hull with

satisfaction, knowing in a few days it’ll be

back in the water, freshly antifouled and

ready for another season’s sailing. He’d

made an effort to collect the scrapings

that surrounded his boat, but he hadn't

bothered to catch them with a tarpaulin

and the marina hadn’t checked his

procedures. Those small flakes are almost

impossible to pick up, aren’t they? So

he’d used a hose to flush them away. The

yacht owner with the red antifouling had

done the same, although he’d let his

young daughter do the hosing. You may

have done the same. And on the other

side of the marina a deluge of flakes is

landing on a gravelled area where it will be

impossible to pick up.

At the top end of the marina a large

cruising yacht is being hauled, and as it

hangs in the slings the marina staff go to

work with a jet washer and blast a residue

of weed and antifouling from the hull

straight onto the hard. It takes about 20

minutes, and when the work is complete

there is a blue, weedy layer covering a

large area of the hardstanding. They use

the jet washer to shepherd it into the

marina where it causes a large blue slick

to form. The hardstanding eventually dries

out and a blue residue covering

approximately 250sq m remains. It’s thick

enough for vehicles to leave tracks, and

it’s there 365 days a year as more boats

undergo the same procedure.

Sanding: wet versus dry

It’s a fairly still day, and some boat owners

have decided to carry out some sanding

and painting. Some are using electric

sanders on large areas of the hull and

deck, and others are wet sanding small

areas by hand. Not one of the electric

crowd are using any form of dust

extraction and what isn’t dispersed by the

breeze collects under the boats. It’ll be

hosed into the marina later along with the

wet sanding residue, although some will

collect in the grassed areas. One of the

painters has finished his work, and he

drives away leaving the open tins and

Talking point

We protect ourselves when applying

antifouling paint, but how much protection

is there for the marine environment in the

UK when the stuff is removed?

Gary Blake