Anchoring in Heavy Grass & Weed

[Mr B]

I was trying out my new hoop type anchor in about 6 feet of water,
It had long grass and very soft mud underneath,
I was on the edge of the channel where I knew the tide was going to be the strongest,
After about 6 times of trying to get it to set, Fast, Slow, letting the boats weight and movement to set it, Changing direction, Dragging it back and forth,
I had about 15 feet of chain out,
The mud and grass was just a big blob on it, It just wouldnt set, I was still dragging slowly,
I then put my 40 Kg anchor out as well, It works but I have never tried it in grass,
It was also dragging slowly in the mud and grass,
Then I put my medium sized Danforth off the stern, It just wouldnt look at it,

3 anchors out, 75 Kgs in total weight of the hoop type anchors and the Danforth,
4.5 ton of Catamaran, and I was still dragging very very slowly,
3 tide changes and an hour in a storm that blew thru for about an hour, 25 knots and metre high waves, BOM predicted 40 Knots,
I was a good kilomtre off shore totally exposed to what ever came thru, as I wanted to see if the anchor worked or not, My First real test of it,
I did get a good bottom clean sitting on the grass and mud in a foot of water, ,
In future, I just wont anchor in grass,
I will also find a nice protected spot to anchor in with out the constant wave action, and no wind to rock the boat all night,

[conchaway]

Take ASA 101, 103, and 104.

[GILow]

Another vote for the Marsh Stockless, now sold by North Haven marine. Specifically suited to the dense seagrass we see here in South Australia.

https://nhmarine.com.au/about-us/#anchor1

Sets reasonably well, but not nearly as fast as my SARCA Excel. However, unlike the Excel, not at all troubled by seagrass or weed.

[Dave Isom]

[QUOTE=Dave Isom;3115352]There is a lot of kelp (thick leather-like weed) off the SE coast of Tasmania.... well there was but much has disappeared due to warming waters. The only anchor which can be relied on in weed is the fisherman’s or Admiralty style anchor. It has long flukes and pointy ends which can penetrate weed. These anchors are not in vogue today so you might have to search for one....bigger the better. If you’re unsure of what they look like, they’re the traditional pattern,”old style”if you like....with a removable bar which ensures the flukes face square to the sea bed.
Using a “Kellet “or weight on the chain helps catenary effect too. The kellet loops on the chain but must be off the seabed.
Good luck...Cheers from Downunder...

[UFO]

Thanks for all the replies - Looks like the wrong anchor for the job. Fortunately this is not my normal anchoring situation, so I think I'll avoid splashing out more dollars on another heavy and bulky anchor just for weed, I already have a fortress as a second so that should cover me hopefully - I'll do more homework and just avoid it in the future.

[mawtty]

Fisherman's anchor, like you see in old ships, works well in weed.
Not too heavy and can be stored flat when bar is unpinned.
Tulku Tim.

[davefrediam]

I have a 30kg Budgel anchor (on a 12m 14 ton yacht) and have only had problems with weed once. It was at Studland bay in about 4 - 5 meters of water. I thought I had dug the anchor in but the wind veered by 90 deg and picked up from 12 to around 35 knots. We had settled in for the evening so were just in pajammers when I checked the pilothouse plotter because of the rising wind and found we had dragged around 500 meters and were making a steady half a knot NNE! Luckily Studland is a huge anchorage. When I raised the anchor it was literally a ball of grass weed (it could never have redug in). I cleared the anchor of all weed and redropped it around the same spot and gave it an extra 15 meters of scope (from around 27 meters to 40) and it dug straight in and held all night no problem.
So my advice for weed would be:
Use plenty of scope.
Ensure the anchor is not dragged at all before the full scope is out.
If the anchor does not dig in straight away the chances are it wont at all and will need cleaning and resetting again.

USE AN ANCHOR ALARM!

Dave

[Mr B]

Originally Posted by GILow

Another vote for the Marsh Stockless, now sold by North Haven marine. Specifically suited to the dense seagrass we see here in South Australia.

https://nhmarine.com.au/about-us/#anchor1

Sets reasonably well, but not nearly as fast as my SARCA Excel. However, unlike the Excel, not at all troubled by seagrass or weed.

That Queensland Police boat I mentioned in Western Port Bay,
It was built by Hart marine at Yaringa Marina, Vic,
Its a Mono Hull and does 46 knots,
It cant go to Queensland as it cant get past NSW due to the lockout by the Virus,
It needs to refuel in NSW on the way to Qld,

Cheers, Brian,

[Marc13]

I am race comittee chairman at Marseille in the Mediterranean sea and we regularly anchor our race comittee boat with a lot of wind and sea on seagrass beds. The best solution is to use plow type anchors like the DELTA from LEWMAR which are perfect. They penetrate the seagrass and hang on the bottom while the flat anchors only land and hang on the seagrass.

[BlackHeron]

IMHO a Fortress is not a primary anchor, and poorly suited for that use. Its strengths are that it is lighter for its size and stows flat, yet still has large surface area on its flukes for its light mass.

A Danforth style steel anchor already is more difficult to set. The lighter weight of the aluminum Fortress makes setting it more difficult, even through minor grass or in a gravely bottom. Personally I would not trust a Fortress without seeing it from the top through a look bucket or diving on it. And then all bets are off once the current and/or wind sits as it can not be trusted to reset on its own. It needs to be reinspected and likely reset for the new direction manually.

As a lightweight supplimental anchor that doesnt weigh much or take up too much space the flat aluminum form of the Fortress is great. Before a storm as a second anchor with time to dive on it to ensure it is set is what it is for IMHO. But in the roller at rhe bow? Makes little sense to me.

The Danforth doesn't really fit a roller all that well, and the added weight of a steel new-generation rollbar anchor doesn't make much difference on a cruising boat tucked into a good bow roller and with a good windlass to lift it.


Now on a race boat that rarely anchors, I can see it as the primary, stowed in a small anchor locker and the boat not having a chain rode or even much of a bow roller at all, if any. Many race boats tend not to carry heavy gear that isn't necessary to go around the racecourse quickly. If this were "Racers Forum" inatead of Cruisers Forum I suppose my rhinking here might be different.

[rslifkin]

I've seen a few roller setups that hold a Danforth / Fortress well, but not many. A through-pulpit roller at the right angle works, as it can tuck flat to the bottom of the pulpit. However, on a boat with dual rollers or a big pulpit (one mounted through, one deployed over the top/end), it would make sense to carry your primary and a big Fortress up forward, as it's not a big weight penalty and it reduces having to manually fiddle with a big anchor in less than ideal conditions when you end up needing it.

As far as use, I'll agree they're not a great primary in most parts of the world. In my mind, they're meant for use in soft-ish sand or mud, basically anything where it can get a good bite to set. And ideally soft enough that you can power-set it deep enough to avoid it tripping out on a reversal.

[MicHughV]

The anchor is only one component of anchoring your boat under difficult situations, one must also factor in:
Chain, anchor rode or any combination thereof...
Scope....
Tidal current....
Your boats behavior at anchor, does it dance around, etc, etc, etc...

For me, I'm a big proponent of the Bruce....plus 75' of chain and then the nylon rode...the chain helps provide a horizontal load on the anchor and the nylon rode provides some spring absorption.

I have dove on my anchor numerous times in numerous different bottoms and wind conditions..and I can't remember a time when this combo dragged.

Sometimes have to put two anchors out in strong current conditions.

My boat lays to an anchor like a baby, but I've seen many boats which are dancing a jig while anchored...

Over time, I experimented with numerous different anchor designs and anchor rode options, but the setup I've just explained...works best...for me!!

A lot will depend on your personal boat. There is no one size fits all here !

[DeValency]

Had the same experience in the (locked out) Bahamas last month. My 55lbs. Delta was helpless, but my second, a modified Fortress did the job right away. For grassy bottom you need very sharp and narrow flukes - Rocna is the opposite.

And lucky you! It is the cheapest anchor and on a cat you can easily find a place for it.

Originally Posted by UFO

So I tried to Anchor where the grass is around 2 feet long and the bottom is densely covered with Grass and Weed - No Sand patches at all.


I have a 40KG Rocna and 12mm Chain on a Lagoon 440 - After the 3rd attempt, the conditions were benign, so I decided to snorkel down as the boat was being held on the chain and the depth was only 3.5m.


The Anchor was just sitting on its side, so I got the better half to back down - Under idle it did not move at all, but with a bit of power it just skidded across the weed.


Fortunately a mooring came free and I took that, but then proceeded to watch a couple of other boats (Mono and Powerboat) try to anchor multiple times with no success.


If I had Scuba gear, I could have cleared a patch and guided it into the sand underneath as it was backed down, but that seems a bit excessive to anchor



So my question is, is there a technique or any tips for anchoring in such conditions?

[IanTrail]

My everyday anchor on my Nicholson 45 is a 30kg Spade. It is great on everything except weed (probably not good on rock either but I like rock even less than weed). On weed I just cannot tell what I'm hooked on; maybe the mud or maybe the weed. I have seriously dragged on weed too often.

So now if I have to anchor on weed I use my 32kg Fishermans. OK, it doesn't have the surface area of a modern anchor so it has less ultimate holding power. BUT it does cut straight through the weed and when setting the anchor it feels like the boat has hit a brick wall! I have never dragged on the Fishermans.

The main disadvantage is swapping the anchors over on the chain, which obviously has to be done underway before anchoring. Playing with 30kg anchors on the foredeck risks tacking lumps out of the deck, feet, fingers etc. But I find it's the only way to feel safe anchored on weed and it looks impressive when stored on deck!

[Salmonater]

In the Pacific Northwest where I cruise, we’re taught not to anchor in eelgrass (seagrass) beds. Seagrass meadows provide critical habitats for juvenile fish, including herring and salmon, crabs, and a host of other important marine life. Recent scientific studies demonstrate seagrass meadows filter marine pollution and protect humans from harmful bacteria found in sewage and land runoff.

Anchors and anchor rodes tear up seagrass beds. Meadows in popular anchorages have been damaged or destroyed. Most cruisers here anchor <30’ or use mooring buoys provided by county and state authorities to minimize seagrass impacts at popular locations.

I suspect the ‘heavy grass and weed’ where you are trying to anchor provide similar ecological services. Moreover, seagrass meadows are not good holding grounds. I recommend you anchor in deeper water, secure your boat, and help protect the marine environment we all enjoy as cruisers.