How much anchor rope and/or chain is needed for safe river navigation?

[border collie]

I am about to buy an anchor and line suitable for river cruising. My boat is a 50' steel narrowboat. Can anyone advise me whether I need rope or chain or both, and roughly what length? Some rivers I may end up navigating are the Avon, non tidal Thames, Ouse (Yorkshire).

Thanks. bc

 

[Paul's Nulife4-2]

Hi ya, And welcome to the Boards,

 

It may help you to do a search for 'Anchor' threads, There has been a few over recent months for you to read through, loads of information & views, & different applications

If no luck then give another shout.

Happy hunting.

Edited June 27, 2014 by Paul's Nulife4-2

[Alan de Enfield]

Welcome - a common question and if you put in "anchor size chain" into the search box top right of the screen you eil find dozens of topics.

 

Here is one to get you started

 

http://www.canalworld.net/forums/index.php?showtopic=63416&hl= anchor type chain

[Leo No2]

When we took part in the Queen's Diamond Jubilee on the Thames the PLA insisted on 10m of 10mm chain and 30m of 14mm (min) anchor warp. That may have been sensible for the depths on the tidal Thames but most of us thought it was overkill for a narrowboat and quite unmanageable should you need to deploy it. The anchor warp is OK but we all felt that 5m of 10mm chain would be a maximum we'd feel comfortable deploying.

 

Hope this helps.

[Alan de Enfield]

When we took part in the Queen's Diamond Jubilee on the Thames the PLA insisted on 10m of 10mm chain and 30m of 14mm (min) anchor warp.

 

To be honest I would'nt have thought that that was suficient (unless you had an anchor on the end)

 

In all seriousness 10mm anchor chain has a breaking strain of about 6 tonnes. Whilst 3 strand, 14mm Polypropylene rope is only about 3 tonnes.

 

A 15 tonne (ish) Narrowboat going with 2 or 3 mph 'flow / tide' would put one heck of a shock load on the anchor system. Admittedly the rope would have some stretch but I would be seriously looking at the weakest 'link' in the system, be it the attachment of the bitter-end, the shackle / splice between rope and chain or the chain to anchor attachment

[blackrose]

When we took part in the Queen's Diamond Jubilee on the Thames the PLA insisted on 10m of 10mm chain and 30m of 14mm (min) anchor warp. That may have been sensible for the depths on the tidal Thames but most of us thought it was overkill for a narrowboat and quite unmanageable should you need to deploy it. The anchor warp is OK but we all felt that 5m of 10mm chain would be a maximum we'd feel comfortable deploying.

 

Hope this helps.

 

Is 10m of chain really any more difficult to deploy than 5m? If I have to deploy my 10m of 10mm chain I don't envisage having to pick it all up at once and chuck it in.

Edited June 27, 2014 by blackrose

[Paul's Nulife4-2]

I agree with Alan on this one, & would add.

Not to mention probably voiding your insurance if you went any thinner or lighter in ground tackle than the old 'Fit for Purpose for size ,weight & Characteristics of vessel in a given cruising area' chestnut, & ofcourse the recommendations of Both the Anchor / Chain / Warp Manufacturers.

I for one wouldn't risk Life n limb, my Investment, My Home or Possible damages for the sake of a suitable Chain,Warp & Anchor.

 

just my take on things.

[blackrose]

I am about to buy an anchor and line suitable for river cruising. My boat is a 50' steel narrowboat. Can anyone advise me whether I need rope or chain or both, and roughly what length? Some rivers I may end up navigating are the Avon, non tidal Thames, Ouse (Yorkshire).

Thanks. bc

 

 

Welcome to the forum. I think this question falls into the "How long is a piece of string?" category...

[John V]

 

A 15 tonne (ish) Narrowboat going with 2 or 3 mph 'flow / tide' would put one heck of a shock load on the anchor system. Admittedly the rope would have some stretch but I would be seriously looking at the weakest 'link' in the system, be it the attachment of the bitter-end, the shackle / splice between rope and chain or the chain to anchor attachment

 

One of the reasons for having plenty of chain is that apart from keeping the angle of pull on the anchor as near horizontal as possible, the curve of the chain and warp act as a shock absorber. This is why you also have to make sure you have sufficient total length of chain and warp

[George94]

 

To be honest I would'nt have thought that that was suficient (unless you had an anchor on the end)

 

In all seriousness 10mm anchor chain has a breaking strain of about 6 tonnes. Whilst 3 strand, 14mm Polypropylene rope is only about 3 tonnes.

 

A 15 tonne (ish) Narrowboat going with 2 or 3 mph 'flow / tide' would put one heck of a shock load on the anchor system. Admittedly the rope would have some stretch but I would be seriously looking at the weakest 'link' in the system, be it the attachment of the bitter-end, the shackle / splice between rope and chain or the chain to anchor attachment

 

Polypropylene has some stretch, but more importantly, so does chain. The weight of the chain means it takes a huge force to straighten it out, and this acts as an excellent shock absorber.

 

If you don't use chain, then it's best to use nylon rope, which is very stretchy. That's why climbers use it.

 

ETA: John V beat me to it.

 

ETA 2. 10 m of 10 mm chain weighs 21 kg. Add in the anchor, and you've got over 40 kg. Not easy to lift without a winch of some kind.

Edited June 28, 2014 by George94

[Naughty Cal]

You really need to know the depth of water you are likely to be anchoring in.

 

As a general rule of thumb if you use all chain 3 times the water depth is required, 6 times if using a mix of chain and rope and 10 times if using all rope.

 

We use all chain but do have a winch to launch and retrieve it.

 

There is little point in skimping on anchor size or chain and rope length. You need to be sure that if you need to use it then it is up to the job.

 

Also make sure that where you attach it to the boat is suitable.

[Bobbybass]

You really need to know the depth of water you are likely to be anchoring in.

 

As a general rule of thumb if you use all chain 3 times the water depth is required, 6 times if using a mix of chain and rope and 10 times if using all rope.

 

We use all chain but do have a winch to launch and retrieve it.

 

There is little point in skimping on anchor size or chain and rope length. You need to be sure that if you need to use it then it is up to the job.

 

Also make sure that where you attach it to the boat is suitable.

 

I 'echo' that..

 

I 'think' this is the RYA recognised length as well ?

 

Bob

[border collie]

OK. Decision made, anchor ordered, rope and chain bought and awaiting splicing, shackles etc. Many thanks for all the extremely informative replies. bc

[Naughty Cal]

When you fasten it to the boat make sure it is easy to cut off in an emergency!

[George94]

When you fasten it to the boat make sure it is easy to cut off in an emergency!

 

What sort of emergency do you contemplate? A tsunami?

[John V]

 

What sort of emergency do you contemplate? A tsunami?

 

Emergencies are the things you didn't contemplate

[George94]

 

Emergencies are the things you didn't contemplate

 

Speak for yourself.

[Bobbybass]

 

What sort of emergency do you contemplate? A tsunami?

 

That's a strange thing for a boater to say ?

 

Maybe....you are new...and your knowledge of safety on the water came from the back of a matchbox ?

 

It is also bad attitude to impart to the OP who is a new boater asking advice.

Living on a boat does not make you a boater...any more than looking at heads makes you a brain surgeon.

 

You NEVER EVER know what the water...or a boat can do....

Maybe if you just park yourself in one spot and never move...you are safe enough...

Even then people are found drowned every year...where they come back pickled from the pub...display scant regard for the hazzards of water...and fall in.

They probably wish they had paid more attention to safety at that point.

 

If you don't understand that..you are a danger.

 

Assumptions..that you know it all when navigating...could kill you.

 

That's what keeps my mate in the RNLI busy every day.

 

What sort of emergency..?

 

Well...for instance....your engine cuts on a flowing river....

You throw out the anchor.. which you do in a hurry and panic as you are drifting...

It all 'unfolds' in seconds.

 

The anchor hits bottom...you come to a juddering halt...and the force starts to pull your bow down...

You realise that in your panic you made a huge miscalculation...and there is the danger that you will scupper the boat...

 

You cannot undo the rope now as its tight...has locked onto the cleat...and is holding 18 tons against a huge flow.

 

Thankfully...you have anticipated this...reach for the knife and cut the rope...

 

That kind of care and anticipation of problems...makes you a good boater....

 

Note..I say 'good' boater..as there is no such thing as perfect....apart from ..maybe..?..George94 and what he learned from the back of a matchbox ?

Edited July 4, 2014 by Bobbybass

[John V]

 

Speak for yourself.

 

prat

[Bobbybass]

 

prat

 

Gosh...why write a whole section when one word will do...?

 

If you read my post above this....that's what I was trying to say....

[Naughty Cal]

 

What sort of emergency do you contemplate? A tsunami?

 

You might not value you safety but dont assume others also dont value their safety.

 

If your anchor gets wedged/snagged and your boat is in danger you need to be able to cut the anchor free of the vessel.

[George94]

 

That's a strange thing for a boater to say ?

 

Maybe....you are new...and your knowledge of safety on the water came from the back of a matchbox ?

 

It is also bad attitude to impart to the OP who is a new boater asking advice.

Living on a boat does not make you a boater...any more than looking at heads makes you a brain surgeon.

 

You NEVER EVER know what the water...or a boat can do....

Maybe if you just park yourself in one spot and never move...you are safe enough...

Even then people are found drowned every year...where they come back pickled from the pub...display scant regard for the hazzards of water...and fall in.

They probably wish they had paid more attention to safety at that point.

 

If you don't understand that..you are a danger.

 

Assumptions..that you know it all when navigating...could kill you.

 

That's what keeps my mate in the RNLI busy every day.

 

What sort of emergency..?

 

Well...for instance....your engine cuts on a flowing river....

You throw out the anchor.. which you do in a hurry and panic as you are drifting...

It all 'unfolds' in seconds.

 

The anchor hits bottom...you come to a juddering halt...and the force starts to pull your bow down...

You realise that in your panic you made a huge miscalculation...and there is the danger that you will scupper the boat...

 

You cannot undo the rope now as its tight...has locked onto the cleat...and is holding 18 tons against a huge flow.

 

Thankfully...you have anticipated this...reach for the knife and cut the rope...

 

That kind of care and anticipation of problems...makes you a good boater....

 

Note..I say 'good' boater..as there is no such thing as perfect....apart from ..maybe..?..George94 and what he learned from the back of a matchbox ?

 

Thank you for writing War and Peace for me.

 

It's pretty blooming obvious that you must always be able to untie yourself, which is why I teach people not to "lock" knots when tying off. The King of Norway lost his yacht when somebody did that.

 

It's also pretty blooming obvious that you should try to think the unthinkable when making preparations. Although one might not be able to envisage the precise scenario that leads to an emergency, you should be able to think of most of the things that could go wrong. That is why I disagree that an emergency is something you didn't contemplate. You should have done.

 

For instance, somebody falling overboard on a river is an emergency, but we contemplate it, and take the precaution of briefing people on MOB drill, and having lines and rings available.

 

So, if the emergency was something you didn't contemplate, you weren't fully prepared.

[John V]

When you fasten it to the boat make sure it is easy to cut off in an emergency!

 

 

 

What sort of emergency do you contemplate? A tsunami?

 

 

 

Emergencies are the things you didn't contemplate

 

 

 

Speak for yourself.

 

 

 

Thank you for writing War and Peace for me.

 

It's pretty blooming obvious that you must always be able to untie yourself, which is why I teach people not to "lock" knots when tying off. The King of Norway lost his yacht when somebody did that.

 

It's also pretty blooming obvious that you should try to think the unthinkable when making preparations. Although one might not be able to envisage the precise scenario that leads to an emergency, you should be able to think of most of the things that could go wrong. That is why I disagree that an emergency is something you didn't contemplate. You should have done.

 

For instance, somebody falling overboard on a river is an emergency, but we contemplate it, and take the precaution of briefing people on MOB drill, and having lines and rings available.

 

So, if the emergency was something you didn't contemplate, you weren't fully prepared.

 

Analysis confirmed!

[George94]

I admit my response to NaughtyCal was a little flippant, but I thought she was making a rather obvious point. However, I concede that it would not have been obvious to all, and needed saying. My comment was therefore inappropriate.

 

I personally prefer using rope for anchors, partly for ease of handling and partly because it is easy just to cut it if necessary. Chain presents a problem in this regard.

 

It would be interesting to know what NaughtyCal's solution is.

[bizzard]

If all chain it should be lashed with rope to its anchoring point in the boat whether the chain runs through a hawse pipe and is fixed to the Keelson or wherever or to a bollard on deck for cutting through in an emergency. If the hawse pipe exit has a latch lid, cut the rope and lever the latch off the chain with a big screwdriver to release it.

Edited July 4, 2014 by bizzard