Tuesday, January 10, 2012

Anchoring

Being cheap, and on a limited income, we tend to avoid paying for dock space and anchor our boat instead.  One of the primary qualities that make Alaska such a great area to travel by boat are the almost unlimited number of bays and inlets for anchoring.

My criteria for a good anchorage consist of four things:

Good holding
Either a mud or sand bottom so our anchor digs in and stays put.
Shallow water
Our ratio of anchor chain to water depth (called scope) doesn't vary much,  we try to keep the ratio between 3 to 1 and 5 to 1 minimum, meaning 30 to 50 feet of chain in 10 feet of water. Because we try to keep the ratio the same, shallow water means we can put out less chain and still have good scope.  The only real disadvantage to putting out a lot of chain is that someone (Nicole) has to haul all the chain back on the boat when we leave.
Swing room
Some of the anchorages we use are pretty small, are shared with other boats, or both, and putting out our normal amount of anchor chain would allow us to hit other boats or run aground, both of which are a bummer and only good for entertaining other nearby boaters that might be watching.
Wind Protection
Open anchorages mean more wind hitting the boat, which makes noise and causes the boat to move a lot.  A big, open bay can also allow waves to build with enough wind, adding to both the movement and noise.  Both the pressure on the boat from the wind and the force of the waves puts strain on the anchoring gear.

When we stop for the night, we try to find a place with as many of the above qualities as possible.  In most cases, you take what you get as far as the bottom type.  The charts will many times give a general idea of what the bottom should be, but we have found many places marked one thing and when our anchor comes up it shows something completely different, or there are no notations on the chart at all.  Our anchoring depth is pretty consistent, and even though we look for a place with the least depth over our required 7 feet, we end up anchoring in about 30 feet of water.  With the tides in Alaska pushing 20 feet  at times, the 30 foot depth gives us a bit of "wiggle room" at low tide for our 6 foot keel.  Trying to judge the swing room is probably the hardest part of anchoring, I'm not a great judge of distances and always think we won't have enough room in the smaller bays, but I do a quick circle around our choice of anchoring spots to make sure we have enough depth and that there are no surprises like big, uncharted rocks.  Lastly, when we drop the anchor, we back up slowly while letting out enough chain to get us to a 5 to 1 ratio, then increase throttle until we have a really good, hard pull on the chain to make sure the anchor is set.  Once set, if we are in a small or crowded spot, we can pull back in some chain to limit our swing.

A couple of other things pertaining to anchoring:
Anchor retrieval
Being able to easily retrieve your anchor is not only a convenience, but also a safety issue.  Having a marginal anchor set brings up the decision of living with the uncertainty of a bad set or pulling the anchor and resetting it.  With a poor system in place to pull the anchor many boaters choose to risk their boat rather than endure pulling and resetting an anchor.  For small anchors easy retrieval can be as simple as a good bow roller and a pair of gloves.  Boats with larger anchors and chain rode rely on a windlass.  With a properly installed and adequately sized electric or hydraulic windlass, pulling the anchor is as easy as pushing a button, making the re-anchoring decision an easy one.  Many low-budget cruisers like ourselves don't want the sizable expense or installation hassle of a powered windlass and opt for a manual model.  Unfortunately most people find the manual windlasses are either too slow in retrieval or poorly situated on deck and cumbersome to use, or both, and they are not much better off than hand pulling the anchor.  The one exception we have found is the windlass we currently use, which is a double handle "coffee grinder" style model that works great, but is unfortunately many years out of production and almost impossible to find.  Whatever your current set-up, relocating or re-engineering your current bow roller, windlass, chain pipe, and/or chain locker to have a workable retrieval system is well worth the effort and expense.

Rafting
This past summer we spent several weeks cruising with our good friends Tor and Jess on S/V Yare.  With their twin one year old boys on board it made it much easier to socialize if we tied our two boats together in the anchorages.  We tried both anchoring bow to stern with anchors pulling against each other, and tied along side with only one anchor out, and both methods worked fine.  Having adequate anchoring gear to hold both boats and a lot of "what if" thinking are important to make this work.  We have been rafted to as many as thirteen boats at once and it can quickly turn into a spectacle without adequate planning.

Anchor Types
I added this section in response to some questions from an earlier post.  We currently use a Rocna anchor on our boat, and before that we had a Manson Supreme, which we still carry as a back-up.  These anchors are very similar in design, both perform very well, and I can't recommend this enough as one of the most worthwhile upgrades to a cruising boat.  That being said, I have also used a Delta and a CQR anchor as a primary anchor with good results, have at least experimented using more than a dozen different designs and participated in anchor testing that tested at least a dozen more designs above and beyond those.  There are quite a few good designs out there, and quite a few people with very strong opinions on which is the best.  I recommend the Rocna/Manson/Spade style only because I think they are a little more forgiving and idiot-proof, a trait that is much appreciated if trying to anchor when exhausted, panicked, and/or distracted.  The bottom line here is that anchor design does not matter nearly as much as good technique, and anyone saying differently is trying to sell you an anchor.

There are considerably more entertaining ways to anchor, and we have seen good examples of most of them:

Speed Anchoring
Even though many cruising boats reach a top speed similar to a moderate walking pace, some folks think this is also the correct speed for anchoring.  They will arrive in an anchorage, drop their anchor and a large pile of chain, and then back up as fast as they can to set the anchor.  Some times this results in the anchor skipping along the bottom without catching, other times it catches and brings the boat to a violent stop.  Either way it's fun to watch, unless the boat is backing up directly towards us.

Anchoring by Faith
These folks don't bother with technique, they have faith that everything will work out.  They come in to an anchorage, pick a spot, drop the anchor, and break out the cocktails.  The extra time and bother involved in setting the anchor or checking the holding is for people that worry too much.

Shot-put Anchoring
Probably not an option for us with a 73 pound anchor, but the smaller Danforth style anchors seem to be a favorite for this group.  I guess the idea is to avoid the extra wear and tear on your engine by not backing down on the anchor, but instead throwing the anchor as hard as possible and then securing it to the boat.

Happy anchoring.

1 comment:

  1. I would love to see someone shot-put a 25 lb plus anchor, just so long as they were far enough from me! If only you had video of this spectacle... As for anchoring by faith, that's just a boat sitting in the mud waiting to happen. People are funny. Setting an anchor takes an additional three to five minutes, but I suppose that is valuable drinking time. Maybe it's like flossing your teeth, just too much time when you're tired.

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