Is there a max anchoring depth/boat length ratio?

TheOrs

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Okay; bit of a newbie question possibly but...

25 foot boat/2.5 tons.

I started out with 8kg anchor/8m 8mm rusty chain/40m 10mm warp but I've purchased 10m 8mm galvanised chain/100m 14mm warp.

99% of the time I'll be anchoring in about 10m of (sheltered) water but I want to be able to anchor further offshore if I get engine probe's etc. so I'm thinking of keeping the original warp at the boat end so I end up with 8kg anchor/10m 8mm chain/100m 14mm warp/40m 10mm warp. This would allow me to anchor in deeper water than if I ditch the 40m of 10mm warp.

I can't think of any reason not to keep the original warp but I was wondering if there's a max depth/boat length ratio for anchoring? Is it dangerous to attempt to anchor a small boat in deepish water?


Thanks

Darren
 

superheat6k

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Not many 40'+ will carry 100m of cable. If you have engine problems in deeper water just drift. If you are worried you might drift into the shallows, then just let it dangle (your anchor that is !).

Always have a knife available to release (cut) the cable in an emergency. Most will never need to use it.

If you have an engine failure in deep water, drift onto a shallow shore, and can't find your knife - well it could have been a heart attack or cancer !
 

jfm

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Nothing wrong with your proposal. Its perfectly safe to anchor in any depth, if you have the warp length and if you're not in a traffic-crash zone. you wouldn't normally choose to do it, but if you want/need to then it is perfectly fine

Remember you are spending fuel to carry many kilos of warp around, which you will likely never use. Your vhf+ mobile phone combo is arguably a much better safety device and is much lighter. you might be over-worrying this one
 
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Poole....there's a surprise :-)
Depends what you do with your boat. Nothing wrong or unsafe with anchoring in any depth you choose so long as you have adequate warp. my last boat had 10 metres 8mm chain and a coil (220 metres) of 14mm multiplait and she was under 8 metres. We used the boat mostly for angling. Deepest water we anchored in would have been around 70 metres metres. The most dangerous part of anchoring is the deploying and recovery of your anchor. We use the alderney ring method to recover which works really well but a little experience using the method would be helpful.
 

superheat6k

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OK

Been boating since 1978, so is the alderney ring method similar to the long wait mode, just in a circle !
 

kevburt

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The only real limitation to anchoring depth is the weight of ground tackle you have to haul in. Whatever method you use, when you're over the anchor there will still be at least the length of chain/warp between you and the sea bottom. It might be easy enough to lift that weight on land but hauling in over the bow, especially in anything of a sea could be a problem. Even with a winch there will be a point at which there is too much to be lifted.
 
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jac

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Need to look pragmatically at where you will operate the boat and maximum depth of anchoring.

Around say the solent - the main channel is typically 20-30 metres deep with deeper spots to 50m, However big ships use that so anchoring a bad plan! Out of the channel in say 10m is safer but it's not that sheltered so why anchor?

IN sheltered bays it might be more like 5m so that makes a good anchoring location.

You say you have sheltered spots in 10m so would plan on anchoring there - if the engine dies in deep water then why anchor? you won't hit anything and lowering ( and potentially raising again by hand) will be back breaking. ( assuming no engine so no power to windlass)

If yiou want to anchor deeper for say fishing then that's different - but for that I would suggest a small light anchor to use as a kedge - it will keep the weight down .

Remember that for proper anchoring you need AT LEAST 4 x the depth at high water laid out and ideally 5 or 6 if you want to sleep soundly.
 

TheOrs

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Thanks for the helpful replies, I also have learnt something from this thread; so I think I'll go with the 100m only & save the weight/keep it tidy.

you might be over-worrying this one
The story of my life I'm afraid! :)
 
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