Weed, worm, growth etc in marinas

wombat88

wombat88

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Every year, about now, I go down to the marina and spend half an hour scraping the growth of the floats that support the pontoon adjacent to my boat. With a garden hoe it is an easy task.

I do this because the first time I did it (some years ago) it seemed to make a difference and reduced fouling on my boat. Since then I have changed boats (and anti fouling) more than once.

I used to believe that it discouraged the nearest stuff from leaping across onto my boat's bottom.

Is there any scientific justification for my action?

I never see anyone else doing it...
 
wombat88 said:
Is there any scientific justification for my action? I never see anyone else doing it...
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When they are spawning, fertilised eggs will land and grow wherever suitable including nearby hulls so, removing them from floats may well reduce fouling. If they are just lying on the bottom in shallow water, then still a problem.
 
I can't really believe that it makes any difference. If it does, then the fouling on the side away from the pontoon should be less before the scraping started. This might be complicated by there being more sunlight on one side or other, affecting weed growth. Still, you will have the smartest pontoon in the harbour.
 
There is a large (2500 boat) marina here that forbids in-water cleaning of hulls on the grounds that it increases fouling of nearby boats. (Other ground include increased silting of the slips and liability.) They have no evidence of this claim, saying it is just a "feeling." The real reason, of course, is that they can charge for haul-outs and more frequent painting.

Racers pool resource and have a diver meet them out in the harbor.

Vanuatu forbids all in-water hull cleaning because of invasive species concerns. Australia, Denmark, Sweden, and several US States have measures in place, although these are primarily for commercial ships.

So I too am curious.
 
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Surprisingly little comment or for that matter ridicule. Happy to receive either.

Perhaps we are a bit low on marine biologists.
 
Aren't you remotely tempted to cut and glue-together a tough, hull-shaped tarpaulin, with pool-noodles sewn around its waterline to make it float, so you can isolate your boat from the water around it? I only ask because your boat isn't a deep-keeler, Wombat.

It would rely upon calm water around the hull, so I guess a marina in a river wouldn't work. But it wouldn't be hard to pump the water out of the tarp when the boat is inside, then refill it with a few gallons of fresh water, so the sea-critters that are calling your hull home, find it a less ideal place to live.

I revive the idea now and then, and it is beaten out of town as a non-starter, but I'm keen to try it. Even if it's on someone else's boat. :biggrin-new:
 
Boat bags, tarpaulins with noodles, are not 'common' but there are a few on Pittwater. They can be used with keel boats, a couple of Etchells near our mooring use them. You don't need fresh water. Common practice is to drop some 'American' bleach (powdered not liquid) into the bag. The ends are self sealing 'sort of' and the concept works 'OKish'. Not for big yachts, not particularly cheap - but considered adequate for an Etchells if you cannot dry sail.

They are a little bit of a faff to enter, and leave. Easier with crew, which is commonly or invariably the case if you are racing.

Its quite an old idea.

However if you race - dry sailing is better - because you keep hull weight down. They have a special 'class' here for 'wet Etchells'.


Slight drift - I did conjure with the concept on a smaller scale as a means to keep the prop and sail drive clean - builders bucket with a drawstring top into which you dropped dry bleach down a tube (tube would surface at transom which would have a funnel to ease refiling of dry bleach). It never even got onto the drawing board - to complicated getting a bag or bucket to encase the prop without diving each time. I did think of biodegradable bags, non woven fabrics, as well but it all went into the too hard basket.

Jonathan
 
Neeves said:
...I did conjure with the concept on a smaller scale as a means to keep the prop and sail drive clean - builders bucket with a drawstring top into which you dropped dry bleach down a tube (tube would surface at transom which would have a funnel to ease refiling of dry bleach). It never even got onto the drawing board - to complicated getting a bag or bucket to encase the prop without diving each time...
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Hardly suitable for regular/day to day usage, but when we overwintered afloat in Greece a few years ago and again sat on a mooring in Ecuador for two months this year we did similar: Heavy poly-bag with bleach in it, snorkeled down and fed it over the prop, then fastened it around the shaft with a cable tie; half a dozen boats fitted them in Greece and they made a substantial difference come spring and you could still 'taste' a hint of bleach in the water when the bags came off.
Easy enough to install in the warm water of October, but removing in late March was a tad nippy, not helped by the fact that as we were the first boat planning to leave, so the first to remove, at which point everyone else said: "Well, as you're already in there, could you just..."
Subsequently a friend's done this regularly, though he now advocates using a very lightweight poly-bag; he's found that they survive the winter without breaking-up/leaking and come spring he simply puts the motor into gear, let's the prop shred the bag and leaves the cable tie on the shaft until the water's warmed up a bit. Though when I tried doing it this way in Ecuador - swinging to 2-4 knot tides - the bag had shredded before we returned.
 
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Lots of interesting stuff but just to get back on track I'm not scraping the bottom of the boat with my garden hoe, I'm scraping the pontoon floats in the perhaps misguided belief that removing stuff from close proximity to the boat will reduce fouling of said boat...
 
BobnLesley said:
Hardly suitable for regular/day to day usage, but when we overwintered afloat in Greece a few years ago and again sat on a mooring in Ecuador for two months this year we did similar: Heavy poly-bag with bleach in it, snorkeled down and fed it over the prop, then fastened it around the shaft with a cable tie; half a dozen boats fitted them in Greece and they made a substantial difference come spring and you could still 'taste' a hint of bleach in the water when the bags came off.
Easy enough to install in the warm water of October, but removing in late March was a tad nippy, not helped by the fact that as we were the first boat planning to leave, so the first to remove, at which point everyone else said: "Well, as you're already in there, could you just..."
Subsequently a friend's done this regularly, though he now advocates using a very lightweight poly-bag; he's found that they survive the winter without breaking-up/leaking and come spring he simply puts the motor into gear, let's the prop shred the bag and leaves the cable tie on the shaft until the water's warmed up a bit. Though when I tried doing it this way in Ecuador - swinging to 2-4 knot tides - the bag had shredded before we returned.
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I'm betting the bleach was not needed; just the lack of O2 would do it. Additionally, it will trap the Cu and Zn ions inside the bag, which are lethal at ppb levels. I'd skip the bleach, It may do more harm than good.

Anode in or out? Anode in protects the prop and most of the shaft. IF the anode is expected to protect anything else, you'll need to make other arangments.

In my mind, a cool water boat without a wet suit of dry suit on board is somewhere between under-equiped and unsafe. You need to be able to work in the water.
 
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BobnLesley said:
..........he now advocates using a very lightweight poly-bag; he's found that they survive the winter without breaking-up/leaking and come spring he simply puts the motor into gear, let's the prop shred the bag and leaves the cable tie on the shaft until the water's warmed up a bit. Though when I tried doing it this way in Ecuador - swinging to 2-4 knot tides - the bag had shredded before we returned.
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Obviously not concerned about the damage dumping plastics does, hope anyone doing this gets caught doing it somewhere where stiff fines are the order of the day.
 
I've watched a Marina lift boats and every vessel that was covered in Quagga and Zebra mussels had their hulls power washed and the mussels blown straight back in the river, right by the marina residents boats. So much for pollution control. If I kept my boat there, I'd change marinas after witnessing that.
 
Actionmat said:
I've watched a Marina lift boats and every vessel that was covered in Quagga and Zebra mussels had their hulls power washed and the mussels blown straight back in the river, right by the marina residents boats. So much for pollution control. If I kept my boat there, I'd change marinas after witnessing that.
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Not legal here. It's in their operating permit. The water must be captured and treated.
 
It's not legal here either and I watched it happen daily for a month.
The Australian authorities have a reputation for not messing about when it comes to pollution, but this
is the Thames, run by the 'cash strapped EA.
 
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