Marking your anchor location

[steve77]

We are now in the Caribbean and I expect to come across some crowded anchorages. I would like to use a float and some polypropylene line to mark the location of my anchor. A question for those of you who do this - do you move the float along the line each time you anchor so that it is at the proper depth? Do you just use 50 foot of line and not bother with it as long as you are anchored in less than 50 feet of water?

It just seems like a lot of trouble to keep relocating the float along the line as we anchor in different depths of water.

Thanks for the input.

Steve

[Mike OReilly]

Floats are generally a bad idea. Unnecessarily blocks out a larger area in the anchorage than is needed, making it harder for others to use the space. Also produces a risk to both you, and others, if other boats get fouled on the line. Can foul a prop and/or dislodge your anchor.

I use a float on the very rare occasions when I deploy a trip line. I only do this when I anchor in areas which have a lot of debris on the bottom.

When I do this, I tie a small block to my float. Then I run my trip line from my anchor, through the block at the float, and then tie a weight to the other end. As long as the total length is less than twice the anchorage depth, the line remains vertical.

[Cheechako]

Marking your anchor in crowded areas, as well as putting out too much rode, is a selfish way of hogging up room in an anchorage. Boats turn in a circle at anchor and boats WILL be over your anchor at times in crowded harbors.

[Argyle38]

Originally Posted by Mike OReilly

When I do this, I tie a small block to my float. Then I run my trip line from my anchor, through the block at the float, and then tie a weight to the other end. As long as the total length is less than twice the anchorage depth, the line remains vertical.

Well look at the big brain on Mike!

Seriously, love this idea.

I also have a small float (fishing pot float, so it doesn't get mistaked for a mooring buoy), would only deploy if a trip line was definitely needed, and not in a crowded anchorage.


Edit: Oh, and if you do set one, don't use floating line.

[Edward Bairstow]

I see your point. With 50’ of line between your anchor and the anchor buoy, and a water depth of only 30’, the anchor buoy would move in the direction of the wind or current to some position not directly above the anchor. In the example just given, a triangle with a right angle at the surface 30’ above the anchor would have a hypotenuse of 50’ (the length of the buoy line) and a maximum drift of the buoy of 40’ from the position above the anchor (a 3 - 4 - 5 triangle, according to Pythagoras). I suppose you could shorten the buoy line once you had let out the anchor ride to the desired scope, but this would mean using a tender, or swimming to the buoy - which might not be too bad in your locale, Caribbean waters being so much warmer than those of northern climes.

[billknny]

Originally Posted by Argyle38

Well look at the big brain on Mike!

I also have a small float (fishing pot float, so it doesn't get mistaked for a mooring buoy)...

This^^^^^

Seriously! I have seen people pick up anchor floats believing them to be moorings! A humourous situation if you are there to watch, a potential disaster if you are not.

In general (and there are exceptions) anchor floats will be more of a PITA for you and your neighbors than they are worth. Moving around an anchorage at night, either by yacht or dinghy, becomes really hazardous if there are unlit anchor floats scattered about.

If someone wraps your float line around their prop, and trips your anchor at 2AM on a windy night, you BOTH have a serious problem. This usually isn't much of an issue in mooring fields because the mooring balls are expected, and are typically very close to the bow of the moored boat.

I tend to see anchor floats used by the same people who put out 160 feet of rode in 10 feet of water in a crowded anchorage. How to win friends... NOT.

For those rare occasions where a buoy makes sense, a gallon OJ jug (bright orange plastic) with the line through the jug's handle and a 2 or 3 lb sash weight on the end keeps the buoy above the anchor in the absence of strong winds or currents.

If you feel you need a trip line, you can just use one deeper than the water depth, and lash it the boat end of it with some small stuff to the chain. Use dacron or nylon, and it will sink with the chain, and be out of the way, but available if needed. In a crowded anchorage, this is a much more "polite" solution than a float.

[AiniA]

Back to your original post, why do you want to mark where your anchor is? You should know pretty well where it is because you know how much scope you have. Having a float and line has little benefit and as others have said it can cause problems for you and others. Can see it as a trip line with a difficult bottom but in the Caribbean this is rarely the case.

[Mike OReilly]

Originally Posted by Argyle38

Well look at the big brain on Mike!

Seriously, love this idea.

I also have a small float (fishing pot float, so it doesn't get mistaked for a mooring buoy), would only deploy if a trip line was definitely needed, and not in a crowded anchorage.

Edit: Oh, and if you do set one, don't use floating line.

Ha ... not according to Gord's "genius" questionnaire .

But great suggestion about the actual float. If you must deploy a float, don't make it something that looks like a mooring.

Or as most are saying ... just don't do it.

[a64pilot]

I keep seeing examples of what too much rode is.
But to put it into perspective, if you are in 10’ of water and your bow is 5’ above water then that’s of course 15’.
7 to 1 is considered optimum rode length, so 7X 15= 105’. So think of that when you think someone has too much rode out, but then also add in the length of their boat and maybe a dinghy at the stern.
So average boat eats up a 300’ diameter circle in 10’ of water when anchored at 7 to 1.
That’s a football field for the US crowd

[a64pilot]

What purpose does an anchor float serve? I’ve always wondered that and can’t come up with a good answer.

[Mike OReilly]

Originally Posted by a64pilot

I keep seeing examples of what too much rode is.
But to put it into perspective, if you are in 10’ of water and your bow is 5’ above water then that’s of course 15’.
7 to 1 is considered optimum rode length, so 7X 15= 105’. So think of that when you think someone has too much rode out, but then also add in the length of their boat and maybe a dinghy at the stern.
So average boat eats up a 300’ diameter circle in 10’ of water when anchored at 7 to 1.
That’s a football field for the US crowd

Luckily, if everyone is anchoring properly, this football field can still accommodate dozens of boats. But not if people deploy anchor floats.

[AiniA]

Originally Posted by a64pilot

I keep seeing examples of what too much rode is.
But to put it into perspective, if you are in 10’ of water and your bow is 5’ above water then that’s of course 15’.
7 to 1 is considered optimum rode length, so 7X 15= 105’. So think of that when you think someone has too much rode out, but then also add in the length of their boat and maybe a dinghy at the stern.
So average boat eats up a 300’ diameter circle in 10’ of water when anchored at 7 to 1.
That’s a football field for the US crowd

Couple of things, if you are running all chain you don't need 7:1 unless conditions are extreme. Boats aren't pointing in completely different directions so you don't need a 300' radius in your direction. Obviously boats swing differently at anchor but not that differently so you can get a lot more boats in that space. If a French boat comes they will fit in somewhere even if the anchorage was jammed.

[Cheechako]

Originally Posted by Mike OReilly

Luckily, if everyone is anchoring properly, this football field can still accommodate dozens of boats. But not if people deploy anchor floats.

[Don C L]

As one of the outliers who does use an anchor buoy occasionally, I do it only when I feel the anchor may be in a place where it can be fouled, and hence the buoy is for the trip line. No polypropylene is my recommendation, definitely. First it's not strong enough to be a trip line IMO, and second a polypro line laying around WILL snag props and anger your neighbors. I have a rig like Mike, a block with a line and a light weight (only heavy enough to pull the line straight down! Too heavy a weight and too big a float and your float will be trying to lift the anchor of course!) I understand the idea of running the trip line back to the boat and if I didn't anchor in areas where everyone is anchoring bow and stern, I'd probably do that, but I'd plan on rigging a very small float (as in a bobber) down a few feet above the anchor just to keep the line up off the anchor to prevent it from fouling on it. I have not anchored in your neck of the woods, but except for coral or suspicion of debris on the bottom, I'd expect most folks will say to forego any buoys for anchor location. You can use GPS mark for anchor location or perhaps even more accurately, if you have landmarks to sight and line up on, you can triangulate your position as you drop the anchor. You are looking for things on shore that line up, not taking compass bearings, if that makes sense. But if you must use a buoy for location, then use heavy line-to block on float-to weight method to keep the buoy above the anchor as water depth changes and put a small light on it IMO.

[Edward Bairstow]

I like the idea of a small block on the anchor buoy with a weight to take up slack in the line and keep the buoy line vertical - much better than swimming out to the buoy to adjust the length of the line. When I use an anchor buoy, it is for a polyester trip line used when anchoring in a rocky bottom. Having the trip line straight up and down makes it less of a hazard to other vessels.