Bottom Paint in the Mud

[a64pilot]

Where I am now, I pretty much had to plow my way into the slip during high tide, there is only about 1.2’ tidal change, but of course I’m sitting in the mud most of the time. I’m not worried at all about structure of the boat, but just had a bottom job and was wondering if being mud covered somehow is bad for the bottom paint.

I assume not as many, many boats sit in the mud in places where the tidal swing is large

[thinwater]

I used to have a slip where the keel was deep in the mud frequently, sometimes for days. The areas that were in the mud did not get heavier growth.



Of course, there is always abrasion, if you are plowing through the mud.

[a64pilot]

Originally Posted by thinwater

Of course, there is always abrasion, if you are plowing through the mud.

I had thought that too, but I don’t expect to really move until after Hurricane season

[gonesail]

i kept my boat in a tidal creek where it sometimes dried out in the soft mud. i was worried that the thru hulls might get plugged but they did not. it looked a bit sad sitting there surrounded by black mud but had no problems.

[sailorboy1]

is it Seahawk's best???

[a64pilot]

Originally Posted by sailorboy1

is it Seahawk's best???

Could be

[sailorboy1]

Originally Posted by a64pilot

Could be

must not be or there would already be hard growth on the boat and the mud would only be a plus because maybe it had something effective in it

[thinwater]

FWIW, I was using Petite SR 40.

[stormalong]

If you plowed through the mud you have already abraded the bottom paint off the bottom of the keel. I seem to do this after ever bottom job and the barnacle growth starts. Paint is Petit Trinidad SR. Plenty hard but the mud takes it right off.

[a64pilot]

Originally Posted by stormalong

If you plowed through the mud you have already abraded the bottom paint off the bottom of the keel. I seem to do this after ever bottom job and the barnacle growth starts. Paint is Petit Trinidad SR. Plenty hard but the mud takes it right off.

I hope not, it’s real soft mud, like pudding. You only know your in it cause the boat gets sluggish and doesn’t steer well, and you of course see the mud churned up in your wash. I think I only plowed about 50 feet or so, but it’s hard to tell, cause depth was reading zero all the way into the fairway.

Running aground in sand or rock is how I usually abrade my keel.
By bottom job time, the chin part of my keel is bare fiberglass usually.

But if it did wear off the paint, it’s only the bottom foot at most, and I don’t usually get much growth there.

[AndyEss]

Buried in the mud might expose the bottom paint to a reducing (anaerobic) environment. Elemental copper might start reducing to a copper sulphate. I don't know if copper sulphate is as toxic to marine growth as is elemental copper.

[RaymondR]

Originally Posted by AndyEss

Buried in the mud might expose the bottom paint to a reducing (anaerobic) environment. Elemental copper might start reducing to a copper sulphate. I don't know if copper sulphate is as toxic to marine growth as is elemental copper.

I think it's the copper compounds which form from the action of oxygen and sea water which is inimical to marine growth. Copper sulphate is called bluestone and is sold fore use as an antifungal.

[a64pilot]

Originally Posted by RaymondR

I think it's the copper compounds which form from the action of oxygen and sea water which is inimical to marine growth. Copper sulphate is called bluestone and is sold fore use as an antifungal.

I believe you are correct, because pure metal copper doesn’t inhibit marine growth, if you don’t believe me, hang a piece of copper pipe in the water and see. I tired it years ago and there was plenty of growth.

It’s why I am very suspicious of Copper Coat, and why adding copper powder in bottom paint doesn’t do anything.

[a64pilot]

I’ve also heard that they aren’t allowed to dredge here because the mud is contaminated with chemicals from WWII manufacturing of PT boats and landing craft near here.
I don’t know if there is any truth to that or not.

[AndyEss]

Originally Posted by a64pilot

I’ve also heard that they aren’t allowed to dredge here because the mud is contaminated with chemicals from WWII manufacturing of PT boats and landing craft near here.
I don’t know if there is any truth to that or not.

That is a pretty common reason why dredging isn't allowed. The old contaminants are buried and pretty immobile. Dredging re-suspends all those nasties and the contamination starts a new cycle of problems. Sometimes contaminated sediments are even capped in place to keep them buried.