Anchors and Anchoring along the ICW

9 Jul

Anchors– Anchor designs have evolved greatly over the centuries. The Danforth anchor was a breakthrough design in the early years of world war II: a lightweight anchor with superb holding capabilities. After the war, it became the standard anchor for small craft. Its one weakness is that the flukes may get jammed with a stone, stick, or quahog and it will not reset if a wind or current reversal pops the anchor out. The various plow and claw style anchors were developed to address that possible weakness. However, their ultimate holding power did not measure up to the light weight fluke style on a weight for weight basis. The spade type anchor. Rocna, Manson, Mantus, Ultra etc. appear to be the best of both worlds. Although diehard Danforth owners and their Fortress family are very happy with the performance of the fluke style anchor, the spade style anchors have a terrific reputation for coastal cruisers and are now the most frequently used on the ICW.

The Atlantic ICW is a great anchor proving ground. Some anchorages are very protected from winds with sand and mud bottoms. Just about anything you drop will work here. Others are open roadsteads with winds and waves, and often with strong and reversing currents. Here you want to be sure your anchor will reset if changing conditions cause it to pop out. While you do see all three basic styles of anchors on ICW cruisers. The spade type anchor is now the most commonly used.

Rode – Many cruisers prefer an all chain rode. It is not necessary in the ICW, but has some advantages, but also with a few disadvantages. In the ICW there is no place where chafe on the bottom is a concern.  Rope rode is fine; it is all mud, or mud and sand. The advantage of chain is that you do not need as much scope in a crowded anchorage. For equivalent scope there is a deeper catenary, so the anchor holding is likely to be better for any given scope. When you get to the islands with coral, you do not have to worry about chafe on the chain rode. The drawbacks of chain include, added weight in the bow, you will need to set a snubber almost every night, and mud. Chain will bring up mud, a lot of mud. You will want to have a good wash-down system if you are using an all chain rode!

Regardless of your chosen rode, cruising in the ICW you must have the rode marked so you know how much you have payed out. Let’ say your bow roller is 5 feet above the water. If you anchor in 10 feet of water, you would put out 75’ of chain (5:1) or 105’ of rope (7:1). If you are experienced at anchoring, you might be able to accurately estimate the rode ratio by eye as you back down to set the anchor. But let’s say that you are anchoring in 10 feet of water, at low tide in GA. Now you will need to put out more scope to have the correct ratio at high tide when there is 8-9 feet more water. If all chain rode, you will have to add an additional 45 feet of rode. If using a rope rode ,you will need to pay out an additional 65 feet to allow for the incoming tide. If the rode is not marked, it will be hard to judge whether you have payed out enough rode.

Marking – When marking your rode, it is easy to make the system overly complicated. There really is no need to mark the rode more frequently than every 20 feet, though many cruisers do mark it every 10 feet. The rode ratio of 5:1 for chain and 7:1 for rope, are not engineering principles to be carried out to the 3rd decimal place. They are merely suggestions. and rounding up is always encouraged. A bit too much scope is far better than a bit too little. There are many systems used to mark the rode. With rope it is very easy to put a marked plastic tag or a wire tie through the lay of the line, paint is a very long-lasting solution for rope. For all-chain it is a bit more complicated. Painting the chain is one common approach. But the paint will wear off in the frequently used portion of the chain. There are plastic inserts you can put in the links. They get dirty and are hard to see from a distance. Wire ties are one simple way to mark the rode, although they will break off going over the wildcat with time. Almost any system for marking chain seems to require bi-annual maintenance.

Over the years, we have had rope, chain and, rope and chain rodes.  We have used each and every one of the above-mentioned systems.  These day we are cruising will all chain rode.  Our roller is 6′ off the water we typically anchor in 10’ depths. Our first mark is at 15′.  At this mark,  the anchor is hanging 9 feet below the surface,  just above the bottom. The next mark is at 80′.  This is the point of  5:1 ratio for 10 feet of water.  The following mark is 105′, the correct ratio in 15′ of water.  We mark the rode for water depths of 20’, 25’, 30’, 45′, 40’, and so on. Our rode is marked with  ¼”polypropylene rope woven through the links. These rode marks have no trouble going over the wildcat. This system is easy to read from a distance. Is easy to see at night. These markers have stood up through 5 years full time cruising, the marks are still there.

Whether you use rope or chain, it is always wise to have the bitter end secured. You do not want your rode to pay itself out and cast you free. But, on the other hand, the day may come when you must slip your rode to get clear of danger. A sacrificial link which can easily be freed is recommended. Here is an idea to consider. Whether your rode is rope or chain, have a 40-foot length of polypropylene secured at the end of the rode and secured at the boat. If you should have to slip your rode, you can cut the polypro with a knife, and have 40’ of floating yellow line which might allow you to recover your anchor and rode when conditions improve.

 

 1/4″ polypropelene woven through 4 links

 Weaving blue polypropylene through the links.

 Yellow followed by blue marks @ 130′ the proper scope for 20′ depths.

 

 

 Splicing polypropylene sacrificial link to the tail of the anchor rode.

 Yellow polypropylene floats to the surface marking the rode if you have to slip your rode in an emergency.

Comments

  1. Rick Shaw

    I have been teaching lessons about anchoring for years and never thought about the tide factor. Thanks.

  2. Yorgos Doumas

    Yep, a great advice, good comments! For peaceful sleep i always tie a line ashore or a second anchor from the stern. the combination of the forces makes the anchors dig really deep despite their type. Also in a crowded anchorage, I can find a spot to stay there still. For smaller scoop I put the snubber’s hook right in front of the roller and then release chain until it reaches the water, so i save 50′ of chain. If the waves come from a different direction than the wind, I let out the one side of the snubber so the bow can turn more to them.

  3. Jonathan Lewis

    Anchoring can be a testy subject. However, Danforth style anchors should never be used with an all chain rode because the weight changes the shank angle which changes the blade orientation and may cause a poor set or difficulty in setting. Rule Industries recommendation in the old days was about a 5 ft section of chain spliced to three strand nylon. I spent a good portion of my life on the hook and I observed countless cruisers in the ditch experiencing problems because of an incorrect set up. Just a thought.

  4. jack chadowitz

    Adding a bow ring at water line with long nylon snubber reduces depth in the calculation and chafe.

  5. SAIL the ICW

    Years ago we had the 40′ chain and 200′ rode marked every 20 feet using paint. What a pain to keep track of. Once we figured out that we never use less than 75 or 80 feet things got much simpler. now we have 150 feet of chain and 200 feet of rode. If you ever have to let out 60 additional feet of chain is a stormy night, you will really appreciate e the simplicity of the poly solution. In all fairness, we are on Lake Champlain right now Generally we are anchoring in 20-30 feet, so we put out most all the chain every night. But if we anchor in less than 12 feet of water there is a lot of weed. The poly does pick up the weeds.

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