anchor or mooring depth

Discussion in 'Boat Design' started by nimblemotors, Mar 13, 2012.

  1. nimblemotors
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    nimblemotors Senior Member

    what is the range or average of anchor or mooring depth
    for the majority of locations where boats anchor?

    10ft 20ft 40ft 80ft?
     
  2. gonzo
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    gonzo Senior Member

    It depends on the location. Some places with high tides can go from 0 to 30.
     
  3. hoytedow
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    hoytedow Carbon Based Life Form

    The mooring depth should be 1/7th the length of your anchor line.
     
  4. gonzo
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    gonzo Senior Member

    Moorings have shorter lines than anchors due to their weight. They rarely have more than 2.5 times the depth.
     
  5. CatBuilder

    CatBuilder Previous Member

    What they said. You will want at least 100' of chain (3/8"BBB) spliced to 100' of rope rode (5/8") and a real anchor for that boat you just got. Do not use Danforth type as primary. Use a plow anchor that can reset.

    That should do you comfortably up to 20ft of depth at high tide. Normally, that is enough unless in very high latitudes, which you aren't.

    Plus, with your boat, you can anchor in probably 4ft MLW of water without much trouble, meaning you can do 40' to 60' of chain out.

    I'm a little over conservative. Unless the anchorage is very crowded, you'll always find me on a 10:1 scope. I like to "set it and forget it", so 10:1 is good for that purpose.
     
  6. hoytedow
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    hoytedow Carbon Based Life Form

    I misinterpreted "mooring" as "riding at anchor" because the OP referred to the anchor in his question. Oops.
     
  7. Submarine Tom

    Submarine Tom Previous Member


    Range: 0.2 m - 287.3 m

    Average: 10.273 m

    -Tom

    P.S. Sorry, you'll have to do the metric to Imperial conversion yourself.
     
  8. CatBuilder

    CatBuilder Previous Member

    I'm not so sure you did. He did say "anchor" twice and "mooring" once. I think he means anchoring... but I guess we'll see. :)
     
  9. nimblemotors
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    nimblemotors Senior Member

    My question is what is the water depth, i.e. the distance from the surface of the water to the earth below. By saying anchor or mooring, I'm trying to get at a location close to shore, close to a marina but not IN the marina, out where one might anchor overnight or for a week or month.
    I understand this directly relates to chain and rode length, but that isn't my question. How long of a pole do I need to reach the bottom?
     
  10. gonzo
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    gonzo Senior Member

    At low tide many boats sit dry. In other locations they have 100 feet under the keel. You anchor or moor wherever you can or is more convenient.
     
  11. hoytedow
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    hoytedow Carbon Based Life Form

    That depends entirely on how deep the water is. It varies from anchorage to anchorage. The depth of anchorage can vary.
     
  12. nimblemotors
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    nimblemotors Senior Member

    Did you mean to say "it depends" ? The depth depends on how deep it is.

    I like these silly answers to my silly questions.

    Let me ask this, where can I find a map of water depth across the globe, or just along the coasts? is there such a thing? There are topo maps of the US easily obtained, must I buy a chart for every region at so many hundreds of dollars per chart to get the information?
     
  13. gonzo
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    gonzo Senior Member

    Yes you can, they are called charts. They are available through the GPO and other sources.
     
  14. Frosty

    Frosty Previous Member

    Thats very specific information when you dont know what size his boat is or what length, where he anchors and in what depth, for how long in what weather and sooo much to argue about your specific choice of anchor on what sea bottom.

    All the above plus scope, chain weight ---sooo much to take into consideration that it is something that can not be tought.

    You will drag and drag before the penny drops, and that will; probably be years until your old and wrinkled with no teeth and smoke a clay pipe.
     

  15. nimblemotors
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    nimblemotors Senior Member

    So yes, I search shows NOAA provides the data free of charge in electronic form, but only for the USA areas. How about the rest?
    And of course it will be a heck of a lot of work for me to answer my question won't it? I'll need to write the software to do it.

    So maybe if I just ask "how long does my anchor line need to be?" and y'all said, 200ft, I can assume 30ft depth is typically a max, or you say 400ft to be safe, now then 60ft would be the depth, right?
     
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