Anchoring... it ain't rocket
Anyone who's ever spent some time on the water
will quickly come to the conclusion that anchoring a boat is both
the easiest thing to do and the easiest thing to mess up as well
Here are a few simple tips to make it painless...
Some people have written books on this issue so we're just going
to stick to the basics, which should address most problems.
1)- make sure your anchor is big enough.
Yeah, anchor is one of those things were size
matters ! Most boating catalogues have selection charts based on
the size of your boat. Don't buy the smallest anchor but upsize
at least one size. It's often funny to look at boats and see a little
tiny bitty thingy dangling off the bow wondering how do people think
these 10 square inches will hold that boat in place !
2)- Have enough chain.
Chain is what gives you anchor the ability to
bury into the bottom and hold your boat by making the pull more
horizontal and closer to the bottom. Small boats (under 30') are
often limited by weight and space so 10 to 15 feet might be all
you can use. In larger boats, especially with windlass, there are
no reason not to use more chain; If not all chain at least the amount
you will normally use for scope. Ex... if you normally use 75' scope,
then 75' of chain is ideal.
Did you know that chain alone can hold a boat
in light to moderate conditions ? I once anchored in the shallow
waters off Eliott key and the wind shifter over night. The next
morning I went for a swim and was surprised to find my anchor 50'
off my stern with the chain making a long arc under water to the
bow of the boat. The weight and friction of the chain on the bottom
was enough to hold the 53' boat in 10kts wind.
3)- Mark your rode.
How do you expect to know how much chain or line
you've deployed if it is not marked ? and if you don't know how
much scope you have, our chances of the anchor holding aren't too
good... It seems everybody has an opinion about how to mark your
anchor rode, you can buy markers at the marine store or use different
For chain, I like using paint marks. One short
for every 25', one long for every 100'. 3 short means 75'... 1 long,
2 short means 150'. Etc... simple and visible, even at night shining
a spot light on the bow from the flybridge or a larger boat. You
can also use little plastic markers, duct tape or even nylon ties
but they're hard to see from the helm if you anchor using a windlass.
The downside of paint is that it needs to be touched up once in
a while as the paint wears off.
4)- use enough scope !
This is the number one mistake many boaters do
when they try to anchor. Just like chain, the angle at which the
boat pulls on the anchor is critical for the anchor to dig into
the bottom. Normal recommended scope is 7:1 including height of
the bow over water and tide. If anchoring in 10' of water (at high
tide) and your bow is 5' above the water surface, you shoudl use
15 x 7 or about 100' of scope. Yeah, that's quiet a bit but it doesn't
cost you anything, does it ?
If needed, some factors will let you reduce that
to 6 or even to 5:1. Using an oversized anchor or all chain will
increase holding power and reduce needed scope.
If you are anchoring in a crowded anchorage and
can't use that much, try setting the anchor with longer scope then
shorten in a little to gain clearance from nearby boats and reduce
your swinging radius. Normally, when the anchor is set, you can
reduce scope by a factor or 1 or 2.
5)- Don't back up too fast when paying out
Nr. two most common mistake. As the anchor falls
down and you are paying out scope, let the wind or current push
your boat back and use as little reverse as possible. If you back
up too fast, the anchor will skip on the bottom and wont' dig in.
If the wind is really calm, use a little reverse so that the chain/line
does all pile up on the bottom.
6)- visualize where your boat will end up
when coming into an anchorage, look at other boats
to see which way they are facing. Pick a spot on the water where
you are considering dropping anchor and try to visualize how far
back your scope and boat length will go. Make sure you're not too
close to other boats. It's not always easy to do that in a crowded
anchorage and keep in mind that boats swing differently depending
on their shape and also their bottom.
If space is limited by other boats, drop anchor
close to the boat ahead of you to get maximum clearance from the
boat behind and avoid ending up on top of his own anchor. It's just
plain rude since you'll be preventing him from leaving,,,
7)- Right of Swing ?
yes, there is such a thing, although it's not
a written rule... A boat that was anchored first has the right of
swing, so if you come in afterward and wind shifts, it's up to you
to move and give the other guy space. Make sense, doesn't it ?
8)- Know the bottom
Usually when someone fail to set their anchor
or drags as the wind picks up, they end up blaming their anchor
even when they're trying to set it with 3:1 scope backing up at
3 kts. But anchors do have some limitations and while books have
been written on the issue, remember that Danforth (one of the most
popular anchor) don't set well in grassy bottoms as their flukes
can't dig in through the grass.
Pay attention to what other boaters are using
in your area, that may tell you what works best.
9)- Clean that anchor !
this is especially true for Danforth styled anchor
that re prone to getting clogged by grass or even mud. If your Danforth
fails to set, bring it all the way and make sure you don't have
a ball of mud and grass that would prevent it from digging in on
your next try.