Anchoring is a rather important skill. To be able to get your boat to stop and be confident it will stay where you want it to. Being a liveaboard sailor, I see a lot of interesting events which are often caused by poor anchoring skills. I’ve had a number of boats drag anchor and head towards the beach with my boat in their path. In this situation you are then faced with a decision; Flee, Fend or Save.
When choosing a spot to anchor, try to consider what the effect of various wind directions will be on the position of your boat in relation to other anchored vessels. If someone drags anchor and they are directly to windward of you, the option to flee may be difficult. It may be impossible for you to haul in your anchor as it could end up under the vessel that is dragging towards you. If you are really unlucky, their anchor may become entangled with your ground tackle and cause you to drag as well. It’s quite likely that both vessels will collide with each other whilst drifting downwind in the direction of more hazards. In this situation, the only way to escape is to buoy off the end of your anchor chain with a fender and drop it overboard. You’ll then have to return for your anchor when the wind has calmed down. Note that it is important to carry a kedge anchor so that you have a spare.
When faced with a boat dragging towards you, another option is to grab some fenders and fend the vessel off. I guess it depends how much time you have to react, how fast the vessel is dragging and how large it is. If it is a small vessel, you may be able to control it as it floats by. You may even be able to get a line on it and hang it off your stern, but of course you’ll have to consider the impact of the extra weight on your own anchor. The scary thing is when you have a large unattended boat heading for your bow. The potential for damage is huge, not to mention the danger to life. Attempts to fend off may be futile.
So you are left with the option of saving their boat. That would involve going onboard, locating the keys and starting the engine(s) and ultimately either re-anchoring it or taking it to a safe port. You’ll also have to consider the risks of leaving your own boat. There are also legal implications of going on to someone’s boat, which vary from country to country.
If faced with such an incident, it is a good idea to contact the rescue authorities as soon as possible. They can give you advice and, with any luck, send a boat to assist. The chances of this happening in time, may be limited. It very much depends where you are and how many other distress calls are being attended to at the time, which may affect the availability of help.
Unfortunately, dragging vessels are not limited to small boats with inexperienced skippers. Over the years I’ve had to alert captains on boats as big as 40m in length that they are dragging.
As an instructor I’d like to mention a few key points that I believe make the difference to anchoring well.
1) Having enough scope. If your chain or rode is too short, instead of pulling horizontally along the seabed, the anchor will be pulled in a vertical action which is likely to cause it to drag. It is also essential that you get enough weight on the sea bed. The chain is no use in the anchor locker! You are looking for at least 4x the depth in good weather. If using a mix of chain and warp (rope) you should have at least 10m of chain on the anchor and then warp. When anchoring you’ll need to put down at least 6x the depth of the water.
2) Making sure it’s holding. When dropping your anchor, ensure that you are facing into the wind or tide (which ever is strongest) and gently go astern while paying out the chain. This will ensure the chain is nicely stretched out along the sea bed, rather than dumping a pile of chain on top of the anchor. Once you have the desired amount of chain out, keep going astern to dig the anchor in and test it’s holding. Look to the side and take a transit (two fixed objects on the land that line up) and check that they stay in line. You could also use a hand bearing compass to take a bearing on an object. If the bearing stays the same, you are holding.
3) The nature of the sea bed. Read pilot books, check the chart and look at the changing colours of the water. Remember that sea grass and rocks are areas to be avoided when anchoring. Grass will cause a poor holding and you are likely to get your anchor stuck in rock.
4) Check the weather! Just because the bay is protected now, doesn’t mean it will be later on if the conditions were to change.
5) Give yourself and others space. Anchoring culture varies from place to place. It’s the age old argument of “you are too close to me”. Be sensible and respectful.
6) Leaving the boat. Most insurance policies have a clause about leaving boats unattended at anchor, so be aware of that. I’ve heard many stories about people popping to the shop quickly, only to find their boat on the rocks when they return. Be careful!
As always, using logic and common sense will go a lot further than relying on advice from others who have never been where you are. On the other hand, local knowledge can save you many a headache and it’s a good idea to heed warnings of hazards from local boaters.