Posidonia Anchoring

[dgadee]

Just accidentally came across this:

Note how the move from superyachts to all anchoring.

Me, I can't find an anchor that works on the stuff so I leave it alone

 

[Yngmar]

Best technique for Posidonia anchoring I've found is to toss the anchor in like a charter boat and don't set it (but unlike a charter boat, lay out sufficient scope). Then I dive down, find the anchor resting on top of the grass, pick it up (our Rocna has a handy roll bar for that) and jam the tip down under the roots as hard as I can. Now I can surface and signal the crew to put the engine in reverse, watching the anchor below me as it sets with increasing rpm (immediately waving to abort if it doesn't). With the help of the tip jammed in, it usually works the first time. No plowing around, no trenches dug. Otherwise a 25kg anchor is too light to get its tip under there and just sits on top of the strong grass blades most of the time, dragging as soon as the wind picks up.

When leaving, we never drag the anchor out of the seafloor in reverse as shown in that video either (why would you even do that), we get the boat up to almost directly above it and pick it up vertically. This does minimal damage, although you do rip out the roots you were set under.

We still avoid the stuff wherever possible though, as all of this is much more difficult than just finding a patch of sand, if there are any!

Also, there's the sweeping of the chain to consider as the boat swings around. It doesn't harm the grass, but it does utterly destroy the Pinna Nobilis (fan shell) that sticks out like a little tower from the seafloor. It's sad to see, but most everywhere I've been diving, they're already long dead, laying on their sides, shattered to pieces.

Superyachts are best impounded and chained to a harbour wall anyways.

 

[sanjeev79]

I came across with a useful article about the new anchoring law. Read more - What are the French laws on anchoring around Posidonia seagrass? | Yachting Pages

 

[RunAgroundHard]

Quite a dramatic and powerful video showing how anchoring destroys the area of the meadow where anchored.

 

[dgadee]

Quite a dramatic and powerful video showing how anchoring destroys the area of the meadow where anchored.

Aye, but only if you can get the anchor to hold there. Beyond me.

 

[RobbieW]

Since this thread has been resurrected, do remember that the vid is about Mediterranean Seagrass. Not the much tougher variety that grows round the UK, eg studland