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Old 07-06-2013, 10:00   #1
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How to anchor in a tidal river?

How could i anchor in a tidal river and leave the yacht unattended for a long period of time?
The yacht has a 25# plow anchor. I was thinking of putting out 100-150' of chain rode, then setting my danforth off the stern with 50' of chain rode.
Bottom is muddy.
Depth is 15 with a 6' tide
Thanks
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Old 07-06-2013, 10:14   #2
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Re: How to anchor in a tidal river?

If "a long time" should likely do as a mooring using two anchors each attached to a swivel by chain. The swivel would be under water and attached up to boat with another chain and/or pennant.

I think Larry Pardey did something like this years ago when he left Serefin in Mexico (La Paz?) for a month or two. Was in one of their books.
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Old 07-06-2013, 10:23   #3
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Re: How to anchor in a tidal river?

How would you set the anchors, and what type of anchors?
Any more details on this method would be great.
Its a great method to deal with the changing water direction.
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Old 07-06-2013, 10:46   #4
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Re: How to anchor in a tidal river?

I agree that two anchors on a swivel is a good approach for long term anchoring in a tidal river. Even though I hate Danforths as a general purpose anchor, two should work well in this application: mud with the pull in a constant (for each anchor) direction.

Do not use nylon rode. It will catch on your keel and saw itself in half over time.

David
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Old 07-06-2013, 12:00   #5
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Re: How to anchor in a tidal river?

Anchoring in a changing current equals the Bahamian moor. basically two anchors set 180 degrees apart. One in each direction of the current and both off the bow. Also works well where the wind opposes the current and depending on the relative strength of each the boat wants to point in different directions.
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Old 07-06-2013, 12:18   #6
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Re: How to anchor in a tidal river?

Not knowing how open to wind the anchorage is, or how busy, or how wide the river (in case of a slack tide, could a wind blow you into the path of a river barge?), I think your solution could work fine.

I once anchored for a month on a tidal river in Asia. I didn't have room for a lot of scope, a little more than 2:1 at high tide. I put two anchors, a Danforth and a Delta, on a single chain rode and snugged them in as best I could in soft mud. I didn't have a proper swivel (lost previously with a CQR). I then set a small bruce off the stern, on chain and rope, at a little less than 2:1 scope.

When I returned, all the rope and chain was well twisted, but the bruce seemed to have done all the work and not moved.
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Old 07-06-2013, 13:23   #7
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Re: How to anchor in a tidal river?

Quote:
Originally Posted by rtbates View Post
Anchoring in a changing current equals the Bahamian moor. basically two anchors set 180 degrees apart. One in each direction of the current and both off the bow. Also works well where the wind opposes the current and depending on the relative strength of each the boat wants to point in different directions.
I think this would be a bad idea if the boat is not going to be attended. After a few current shifts the rhodes would be tangled and eventually this would affect resetting of the anchors if/when they drag.

I don't think many people do the Bahamian mooring anymore for that reason.
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Old 07-06-2013, 13:32   #8
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Re: How to anchor in a tidal river?

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Originally Posted by JK n Smitty View Post
I think this would be a bad idea if the boat is not going to be attended. After a few current shifts the rhodes would be tangled and eventually this would affect resetting of the anchors if/when they drag.

I don't think many people do the Bahamian mooring anymore for that reason.
Perhaps it's not a Bahamian moor but I thought you brought both rhodes together at a swivel then another length of chain to the boat. The boat pivots around the swivel. Nothing to tangle.
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Old 07-06-2013, 13:45   #9
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Re: How to anchor in a tidal river?

I've done a lot of this (living in the the Washington, DC area over the last couple of decades) in the tidal potomac. As already noted by another poster, we also use a swivel and two anchors and all chain rodes. I like to set a danforth/fortress in each direction on it's own rode and link them to a swivel and a heavier chain up to the boat. No twisting and an even pull in each tidal direction. Takes a few hours to set and retrieve but never dragged when many did.
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Old 07-06-2013, 18:31   #10
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Re: How to anchor in a tidal river?

i got my swivel today, but i had a question, do i need an extra 200' of chain rode?
100' for each scope?
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Old 07-06-2013, 18:46   #11
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Re: How to anchor in a tidal river?

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Originally Posted by scoobert View Post
i got my swivel today, but i had a question, do i need an extra 200' of chain rode?
100' for each scope?
I sure don't have an extra 200' of chain. I would piece together about 100" for the second rhode and live with 200' on the primary.
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Old 07-06-2013, 18:56   #12
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Re: How to anchor in a tidal river?

I left my boat for a month anchored once down in the Caribbean and I put out two anchors with the rodes leading up to the bows (cat). I did have someone check on the boat once in awhile for me, but he didn't have to do anything. The rodes got a bit wound up, but I untangled things pretty quickly. It was not a tidal river. Generally, wind shifts and tidal shifts are not consistent and you will be surprised that some wind things up and some unwind things--tend to average out after awhile. Using the swivel rig is ideal, but not absolutely necessary, especially for shorter stays. I routinely stay for as long as two weeks on a standard Bahamian moor, but someone is onboard.
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Old 07-06-2013, 18:57   #13
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Re: How to anchor in a tidal river?

Quote:
Originally Posted by Dennis.G View Post
If "a long time" should likely do as a mooring using two anchors each attached to a swivel by chain. The swivel would be under water and attached up to boat with another chain and/or pennant.

I think Larry Pardey did something like this years ago when he left Serefin in Mexico (La Paz?) for a month or two. Was in one of their books.
Dennis, where can one get a swivel like that? Thanks
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Old 07-06-2013, 19:21   #14
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Re: How to anchor in a tidal river?

I would not set it and leave. If it is not going to be looked after, I'd stay on it a while and see what it does in the reversing current and some wind/current combos.

I've seen people set two large, cheap danforth knock-offs for a bahamian moor. Really not such a bad use for a that type of anchor in mud, with chain rodes. To weigh it you can buoy one and weigh the other, then get the second.

My preference would be to shackle the chains to a sling link, then come up with another chain from a regular swivel. The heavier chain idea sounds it could work well. Not so crazy about the double swivel thing, but maybe it works great. I'd worry that it would bind. Who makes it? I only buy Crosby hardware.
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Old 08-06-2013, 07:04   #15
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Re: How to anchor in a tidal river?

A few posts have been deleted.
There is plenty to debate about anchoring techniques without having to drift to political issues .
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