Best anchor for deep mud conditions

[jibes138]

I know a guy who has been having repetitive problems anchoring in deep mud conditions in the creeks around the Chesapeake region. I have also experienced deep mud and dragged a few anchors in the NC area. Does anyone have a recommendation for the best anchor for these conditions?

 

[Ross]

Just bigger. with a longer scope.

 

[Shoaldrafter]

Anchors

Dave,

You might have given the forum where this is being discussed:

http://forums.oday.sailboatowners.com/showthread.php?t=139814

And told everyone of your recommendation of an anchor that would work:

Ed K

 

[Don12364]

Contemplate Your Anchor!

Having edited this 3 times and still the site removes all paras and formatting - I give up and apologise on behalf of SBO - with whom I have NO connection whatsoever. Contemplate Your Anchor! Imagine placing your anchor on your flower bed and attaching the rode to the tow hitch on your car or pickup. Then driving off slowly. Would you expect the vehicle to be able to tow the anchor – I would. Yet, in stormy conditions, my boat (H376) can generate far higher pulling forces than my car (Lexus). Also, as the drag proceeds one would expect the anchor to continue to dig in deeper and deeper. In practice this is not what happens to anchors because their shank and the rode travel along the surface of the sea bed and provide an upward lead angle which prevents further burying. Anchorages are normally in quiet areas not prone to strong currents and then consider that the sea bed is only formed from silt and other detritus that has fallen down through the water over millions of years and that this is likely to be even softer than the soil in your flower bed - so it is a miracle that the anchor has any holding power at all. The sea bed is easily fluidized by the boat moving the anchor from side to side and the snatch caused by wave motion only makes matters worse. Visualise again all the above but with the anchor now laid out on a sandy beach and the vehicle on the promenade road surface. Again one would expect the vehicle to win every time. Setting a second anchor may help to resist ‘sailing about on anchor’ but this will only be of benefit if you can stop the boat first pulling on one and then the other. Alternate loading of each anchor simply means they take turn in dragging so this reduced by half. A better way is to lay two anchors in tandem with the second attached to the crown of the first. Over the years I have had excellent results from Bruce, Delta and now Manson anchors – all 35lb size. Yes I can drag most anchors when at full power in reverse with my 3 blade feathering prop and yes these anchors are likely to move under stress of weather. One simply has to accept that anchoring is something of a lottery because the actual state of the sea bed is an unknown factor and the maximum strength of the wind to be experienced is also unknown at the time of setting the anchor. Proper seamanship ensures you are not in an exposed situation when the gale arrives. Many yachts are lost to owners who don’t monitor the forecasts and take proper action in good time. Such individuals get little sympathy from me nor would I expect any from them were I so remiss as to get caught out. Hurricanes and Tornados, of course, are a completely different kettle of fish though. An interesting website for those needing a deeper analysis is that of Frenchman Alain Fraysse – in English or French. He even has a spreadsheet for you to insert your own boat’s details with graphs of anticipated performance and red banner warnings if the rope and chain are not man enough. See:- http://alain.fraysse.free.fr and http://alain.fraysse.free.fr/sail/rode/rode.htm

 

[RichH]

I use either a heavy spade type anchor or a fortress type with an adjustable fluke angle for soft mud anchoring.

With a 'heavy' anchor, in soft mud you simply have to wait for the anchor to 'sink down' by its own weight before pulling any strain to set the anchor ... sometimes up to an hour! Then s-l-o-w-ly increasing strain until it sets. You can decrease the 'settling time' by 'jerking' it to set - simply apply repetitive 'jerks' by hand on the rode and 'worry' the anchor and chain into the mud.

For a danforth type, you need one with BIG flukes and with the adjustable flukes set at at least double the angle of an anchor set up for sand, etc. ... and you still have to 'jerk' it in for it set well ...... and hope to hell that the wind doesnt change direction.

If either of the above isnt firmly secure and I need to be anchored for several days, I will sometimes set the above two in series-tandem, with the large fluke anchor on about 30 ft. of chain at the end of the set-up, the heavy anchor closer to the boat. Some folks I know dont use chain for the fluke anchor but instead use steel cable when setting up anchors in tandem in mud. Also when finally 'pulling strain' its best when pulling strain to pull at 10:1 or greater scope and then when finally 'set' pull in the rode to 7:1 or shorter ... and hope to hell the wind doesnt change direction. Obviously you can use 10:1 when anchoring in deep (~50+ ft. depth) water.

For me, it seems in soft mud the best is let the anchor sink deep into the mud by its own weight before setting, set it 'gently' so you dont rip it out and then 'worry' it deeper into the bottom below the mud.

 

[Ducati]

A Wing Keel works best

Sorry I couldn't resist

 

[Rob2435]

I've used a plow anchor in and around NY(Hudson River, Raritan Bay, Long Island Sound) and have never had a problem, even when squalls passed through with 60MPH winds. It is a "set it and forget it" type anchor. I do, however, make sure I have at least 5 to 1 scope.

 

[Bad Obsession]

I use a bruce type anchor. On my Catalina 30 I have a 33lb pound anchor with 30 feet of chain. It has worked well so far. I back down very hard on mine when I set it also.

I do regret not having about 60 feet of chain. It is because I would usually be putting out the whole chain scope and maybe 10 feet of my rope in most anchoring situations.

 

[Maine Sail]

In my experience, and from actually load testing many anchors with a load cell, the new generation anchors perform exceptionally well in soft mud. The Manson Supreme, Rocna and Spade at the top. The Fortress also performs exceptionally well in soft mud BUT you must have it set for soft mud and be using the mud palms. My problem with the Fortress is they tend to not like to reset on wind or tidal shifts and we almost lost our boat to a Fortress when using it as a primary. The Spade, Manson and Rocna will all re-set on their own and most often just spin on themselves and don't actually un-set to re-set.

While the Bruce is a good setting anchor the holding power is lower per pound than that of the new gen anchors so you often need to go up two sizes+ to equal a Spade, Manson Supreme or some other new gen anchors in sheer holding. We dragged our genuine Bruce, which was generously over-sized, steadily and slowly through soft mud in a storm with winds between 40 & 50 knots. This is 100% unacceptable behavior when on 9:1 scope with an OVERSIZED anchor that was very well set.. It remained set but simply did not have the sheer surface are to hold our boat.

We currently have a 44HP diesel with a fixed three blade prop that can deliver about 600-700 pounds of pull on the anchor for setting (no where near storm loading). We can drag all our anchors, after fully setting them, except the Fortress, Rocna, Manson Supreme and Spade. The CQR drags around the bottom the easiest, then the Bruce, then the Delta..

Plow anchors often do what they were designed to do, plow.... I have had our Spade, Manson and Rocna so buried that it took tide pressure to break them free from the soft mud bottom they started in. In the mornings I often pull up to 1:1.1 or so scope 30 minutes before we are heading out so that our new gen anchor has time to "un-set".. Even soft mud gets hard once you get the anchor in a few feet...

 

[captainpat]

Great discussion! Anchoring/ground tackle is one of those topics that everyone has differing opinions on, oftentimes based on bad, or good, experiences. For my part, no matter the anchor, use plenty of chain. I have a Delta on my 44 with 100' of 5/16" G-4 chain on a swivel plus 250' of three-strand. Considering that I rarely anchor in more then 15' of water in the Chesapeake, I normally don't even get into the three-strand. Even so, I would feel better with an additional 50-100’ chain. Deploying the anchor, no matter what type, demands patience. As RichH said, let it settle into the bottom and GRADUALLY back down on it, slowly increasing the rpm's to about 2000. That should be good up to about 40 knots of wind. As it begins to blow I let out all the chain so it lies on the bottom. Sometimes I think it’s the chain doing all of the work instead of the anchor. I also use a three-strand snubber on the chain. The only time I ever had an anchor drag was in Atlantic City at the Brigantine Bridge. The bottom is so scoured there because of the shallow water and the fast current that it's like anchoring on concrete.

 

[dscribner]

I use a good ol' Danforth and had good luck. If things get hairy, I'll set a second about 10 feet up the chain and hopefully set both. Never had a problem, but Sparrow is a tetch smaller than some of your girls so she probably pulls less in a blow.

 

[MrBee]

We use a Manson Supreme in the Chesapeake Bay.
Drop it down, Set it, at least 5 - 1 scope, more if conditions dictate. NEVER had a problem. I do not understand why people spend many thousands on a boat but go cheap on an anchor. The ONLY thing we use a Danforth style for is a day hook off the stern.

But hey, opinions are like you know what, and ever bodies got one.

Brian

 

[Fortress]

We have exhibited at the US Sailboat show in Annapolis for the past 15 years or so and this has given us a great opportunity to talk firsthand with sailors who regularly anchor in the local area.

First and foremost, sizing up to a larger anchor than a manufacturer's standard recommendation for your boat is wise, since the soft mud bottoms in the Chesapeake Bay insure that the holding power will be dramatically reduced for ANY type of anchor.

Further still, the thunderstorms which come howling through the Bay with 30-40 knot winds insure that your anchor and technique are going to be challenged, so be sure to also have as much scope out as possible to keep a good horizontal pull on your anchor.

Regarding our anchor's performance during a wind or tidal shift, we contend that a well-buried Fortress anchor, with its massive twin fluke surface area, is not more likely to break free than another anchor type in this situation.

That said, although the Fortress anchor is sharpened and tapered for deep penetration capability into a sea bottom, many sailboats simply do not have the engine power to "power set" and back down hard enough to deeply bury the larger Fortress, which will help insure that it will not break free in a veering situation.

This issue is obviously more evident in a harder bottom type (hard clay), but less in a softer bottom (soft mud).

Evidence of a Fortress anchor's ability to handle a wind shift once properly buried can be found in the Sailing Foundation's anchor tests (summary attached) in which they conducted straight, 90 degree, and 180 degree pulls. Once the much lighter Fortress was buried at over 4,000+ lbs of load, it did not break free in the 90 degree and 180 degree pulls when subjected to additional 4,000+ lb. loads.

And so no matter the anchor, be sure to "power set" it as hard as possible if you intend to stay put for an extended period of time, and if it breaks free afterwards, then good....better then than during the middle of the night when that thunderstorm comes crashing through.

Safe anchoring,
Brian

Fortress Marine Anchors