Testing a mooring buoy

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Jklotz

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Being a newbie, and having read the recent thread of the guy who lost his boat to a failed mooring buoy in the BVI, I have a question. What is the proper way to assess the safety of a mooring buoy? Lot's of places won't allow you to throw out an anchor, so, if you want to stay there, you don't have much of a choice. What can you do to make sure your still secured if the wind and waves pick up in the middle of the night? Is there such a thing as a proper procedure for this?
 
If you can dive on it a visual inspection might provide some insight. But other than trying to back down on it to stress test that is all I suspect can be done.
Using an anchor alarm to track your movement would be a reasonable way to monitor if moving outside of the normal swing.

If you follow the wandering hillbilly story it was apparently pretty rough conditions and they left the boat on the ball. I would be hesitant to leave a boat unmanned either at anchor or on an unknown mooring under these conditions. Easy to say this in hindsight so not making any judgment. We all learn from these incidents.

I imagine a lot of sailing megayachts are re-evaluating their procedures in light of the sinking and loss of life this week. From what little is known this was a tragic accident that resulted from some very uncommon weather during a routinely safe anchoring situation.
 
Are we talking about anchoring or a mooring? Anyways, I would go big.

My boat come with a Rocna 20. I sold it and bought a Rocna 25. That went from 44 to 55lbs. I would have gone bigger but the 73lbs one would not fit. But thats me.......

Same on mooring. The local mooring guy suggested 800lbs for $150 more I could get a 1000Lbs.
 
Iggy said:
Are we talking about anchoring or a mooring? Anyways, I would go big.

My boat come with a Rocna 20. I sold it and bought a Rocna 25. That went from 44 to 55lbs. I would have gone bigger but the 73lbs one would not fit. But thats me.......

Same on mooring. The local mooring guy suggested 800lbs for $150 more I could get a 1000Lbs.
Click to expand...
No, mooring ball, not anchor.
 
If it's a rental mooring, the owners tend to make sure it's maintained and adequate for the boat they rent to. After all, it's their liability if it fails. Obviously that's not a 100% guarantee, as not everyone is as diligent as they should be.

If it's one of those "destination" mooring fields which has sprung up in a former anchorage, and your only choice is to take a mooring of unknown size and quality, then you assume the worst. That means not leaving the boat unattended, and not taking the mooring in anything but settled weather.
 
CaptTom said:
If it's a rental mooring, the owners tend to make sure it's maintained and adequate for the boat they rent to. After all, it's their liability if it fails. Obviously that's not a 100% guarantee, as not everyone is as diligent as they should be.

If it's one of those "destination" mooring fields which has sprung up in a former anchorage, and your only choice is to take a mooring of unknown size and quality, then you assume the worst. That means not leaving the boat unattended, and not taking the mooring in anything but settled weather.
Click to expand...
Thanks for that. Makes sense.

One youtuber (forget which one) recommended tying up with a snubber/bridle, puting the boat in reverse at the lowest throttle setting and watching the chartplotter. When it reaches 0.0 knots, hold in that position for 60 seconds. If it stays at 0.0, then he considers it safe. Does this sound like good advice?
 
The only answer I see is, that if the buoy isn't "certified" by at least someone reputable and have regular inspections....one has no idea whether it's "totally" safe.

Testing a buoy at idle is a nice thought....but what boat? Twins with 1000hp with cruising props combined or a single 120hp? You have to concentrate more on the pull of the engines at some guessed RPM to simulate what the max forecast winds are. That might be the equivalent of "test to destruction" technique though....or it might not really tell you much if you aren't using enough reverse pull.

Not saying the 60 second test doesn't tell you anything.... but to me it would only tell me that it might be OK in only the fairest of wind conditions and not much about surviving surge and yaw.

I am with Capt Tom with not leaving the boat unattended in anything but settled weather and only after several hours to see how the boat rides and mooring holds. That time might be best if it includes any daily wind or tidal swings.
 
Several years ago, a friend of mine was helping a sailboater fix his little dinghy outboard. They were on a town rental mooring at Block Island. With the little 6 horse engine idling in reverse they pulled the mooring back about 10 feet before they realized it.
Not uncommon to see them ( “Ace”) tugging moorings back in place there.
 
IMO, a mooring ball anchor is already set. You do not need to see if it is set. Testing/simulating a strong wind may be the straw that breaks the camels back.
Like anchoring once you set the anchor be aware of your position, have a cool drink while you observe any movement. In calm or gentle waves once you are satisfied, then you can leave the boat.
Oh, a good rule to follow, if you cannot launch and retrieve your dingy, do not leave the boat or go to sleep.
But then I am the guy who does not plow the seabed trying to set an anchor.
 
There are so many things to consider - and worry about - when boating. I'm going to put this in the bucket of: don't worry about it. I'm not saying one should never be concerned about a mooring; I've owned several and had them professionally inspected and serviced twice a year. What I mean is that for most pleasure boaters, in most instances, if you're on a mooring, it is of known provenance - either a municipal mooring field (e.g., Annapolis or Boot Key in Marathon) or privately owned, just like marinas (e.g., Sunset Bay in Stuart or Handy Boat in Falmouth, ME). They have an incentive/responsibility to maintain their moorings as they are providing them for a fee, and they also limit mooring use by boat size (usually length, which isn't perfect, but a common way to do this). Outside of formal mooring fields, anchoring is generally allowed. I've never used a mooring that wasn't my own, rented from a town/marina, or known to me (a trusted friend). Some folks will just pull any mooring anywhere - if you don't do that, and few of us would do that, not only for safety reasons but because it's someone else's property - then I put it in the "don't worry about it" bucket.
 
Iggy said:
Are we talking about anchoring or a mooring? Anyways, I would go big.

My boat come with a Rocna 20. I sold it and bought a Rocna 25. That went from 44 to 55lbs. I would have gone bigger but the 73lbs one would not fit. But thats me.......

Same on mooring. The local mooring guy suggested 800lbs for $150 more I could get a 1000Lbs.
Click to expand...
Kind of funny to read. We will not accept a mooring with less than a 5000 lbs block, preferably a 10.000 lbs block. Then we will tie one line on top of the ball and one line below the waterline.
However, if I have the chance to be on anchor I prefer that one. In no way will I stay in a storm on an mooring buoy.
 
After reading some of the comments I am starting to wonder how mooring buoys are fixed in the US.
In Europe they dump blocks of concrete in the water, varying from 1 ton (kg) to 5 tons (kg). A chain is connected to this block and in the end you will find either the chain with the mooring buoy attached to it or a line connected to the chain and then the mooring buoy.

Weight wise the blocks of concrete have more than enough holding power, so no need to 'test' them at all, they won't move. The chains however are the weak point, they are always underwater, will start to corrode after several years in the water and they don't do any maintenance on them. So when the mooring buoys are new they will be OK, but if they are several years old..........I am not going to trust them anymore.
But testing a mooring buoy ? I have never even heard of it. What is the point ? You think you will pick up the whole block and move it along ? If that is the case the block you are attached to is not heavy enough, so why even tie up to that one ?
Am curious how that is organized in the US, can anyone explain ?
 
Agreed, it's usually the hardware which fails, chain or shackles. Concrete or granite (esp in new England) blocks are common, as are mushroom anchors. Less common but increasingly used are screw anchors.
 
Pyramid anchors are becoming popular too.

The USCG years ago studied how concrete blocks can drag a bit too easy on hard sand (mud not so much) and for smaller buoys started using the pyramid anchors. The key is that concrete is only around 60% (I think) as heavy submerged as on the ground so the rule of thumb is the block should be 2X as heavy as the required holding power in mud, much more if on hard sand.

Several marine suppliers like West Marine and Jamestown Dist. plus BoatUS have articles discussing moorings and how to assemble them....plus holding power needed per wind speeds.

I do agree with being suspicious about private moorings as I knew guys that just used old engine blocks, 5 gallon buckets with the chain run through them, and other questionable anchors.
 
jleonard said:
Several years ago, a friend of mine was helping a sailboater fix his little dinghy outboard. They were on a town rental mooring at Block Island. With the little 6 horse engine idling in reverse they pulled the mooring back about 10 feet before they realized it.
Not uncommon to see them ( “Ace”) tugging moorings back in place there.
Click to expand...
My guess would be they pulled the slack out of the chain that is attached to the mooring block / mushroom. There is always slack chain especially at low tide. Thats pretty much standard procedure when monitoring / maintaining a mooring field. We do it often.
 
I'd be reluctant to start pulling on someone else's mooring using engine power. They're surprisingly easy to move, especially if they haven't sunken into the mud. If they're in a relatively protected area, they might not be sized for strong currents and winds. And you don't know if they're sized for your boat.
 
BroadCove said:
There are so many things to consider - and worry about - when boating. I'm going to put this in the bucket of: don't worry about it. I'm not saying one should never be concerned about a mooring; I've owned several and had them professionally inspected and serviced twice a year. What I mean is that for most pleasure boaters, in most instances, if you're on a mooring, it is of known provenance - either a municipal mooring field (e.g., Annapolis or Boot Key in Marathon) or privately owned, just like marinas (e.g., Sunset Bay in Stuart or Handy Boat in Falmouth, ME). They have an incentive/responsibility to maintain their moorings as they are providing them for a fee, and they also limit mooring use by boat size (usually length, which isn't perfect, but a common way to do this). Outside of formal mooring fields, anchoring is generally allowed. I've never used a mooring that wasn't my own, rented from a town/marina, or known to me (a trusted friend). Some folks will just pull any mooring anywhere - if you don't do that, and few of us would do that, not only for safety reasons but because it's someone else's property - then I put it in the "don't worry about it" bucket.
Click to expand...

I'm in this camp. If the weather looks reasonable, I worry much more.about other things. And if weather is bad, then get to a dock (or at least away from other vessels I don't trust).

Of course some buoys are obviously terrible looking and we avoid those. Mostly here in WA State we use State Park buoys (not all trustworthy but with some baseline competence). Those more or less match BroadCove's points.

IMO the main buoy security factor after Wx forecast is this : Anchor Pro app to sound an alarm if we drift!
 
We were on one with trawlers, 2007-2015 before moving onto a marina. I had the apparatus lifted and checked annually. When we upsized the boat, a double size block replaced the single.
It`s vital the apparatus is serviced annually. When I had a sailboat I recall getting a report from the mooring contractor that he had got there "just in time" before an underwater shackle failed.
We regularly use National Parks moorings which I know get serviced. You see evidence of servicing, line repairs and maintenance, actual contractor on site lifting and checking, I tend to trust them without testing but I do look at the visible parts of the mooring.
There are 3 bays on the Broken Bay/Hawkesbury river system with many privately owned, and Club owned, moorings. These are not permanently used by their "owners" and habitually used by others if vacant, so much that it has become customary(even if it is wrong). The Club owned ones are probably ok, the others, who knows? Even though the Maritime Authority license to install the mooring apparatus requires annual servicing, but does it happen. I would definitely test these by loading before, use if I used one. If loading up causes it to fail it was a good test, same as if it withstands testing. I`ve been on one in Refuge Bay with the IG36, in a "southerly buster" (low pressure strong wind front) strong enough the mooring ball was pulled out of and horizontal to the water. Held just fine, but I was nervous and relieved (possibly relieved once during the blow too) when the front passed.
 
Mambo42 said:
After reading some of the comments I am starting to wonder how mooring buoys are fixed in the US.
In Europe they dump blocks of concrete in the water, varying from 1 ton (kg) to 5 tons (kg). A chain is connected to this block and in the end you will find either the chain with the mooring buoy attached to it or a line connected to the chain and then the mooring buoy.

Weight wise the blocks of concrete have more than enough holding power, so no need to 'test' them at all, they won't move. The chains however are the weak point, they are always underwater, will start to corrode after several years in the water and they don't do any maintenance on them. So when the mooring buoys are new they will be OK, but if they are several years old..........I am not going to trust them anymore.
But testing a mooring buoy ? I have never even heard of it. What is the point ? You think you will pick up the whole block and move it along ? If that is the case the block you are attached to is not heavy enough, so why even tie up to that one ?
Am curious how that is organized in the US, can anyone explain ?
Click to expand...
More and more of the municipal moorings (on the East coast anyway) are of the helical screw style mooring anchors. These type are literally screwed into the bottom by a machine on a barge. A diver installs the chain. They are engineered based on the substrate where the mooring field is located.

Friend of mine is a commercial diver who occasionally works on them. They are inspected every few years (can't remember the intervals) by removing the screw from the bottom and either reinstalling it or replacing it, and like wise the chain. While probably not economical for individual moorings, when working on a mooring field, the inspection process is surprisingly quick.

Ted
 
O C Diver said:
More and more of the municipal moorings (on the East coast anyway) are of the helical screw style mooring anchors. These type are literally screwed into the bottom by a machine on a barge. A diver installs the chain. They are engineered based on the substrate where the mooring field is located.

Friend of mine is a commercial diver who occasionally works on them. They are inspected every few years (can't remember the intervals) by removing the screw from the bottom and either reinstalling it or replacing it, and like wise the chain. While probably not economical for individual moorings, when working on a mooring field, the inspection process is surprisingly quick.

Ted
Click to expand...
So they are screwed into the sea bed ? No block of concrete holding down the chain ?
That is indeed completely different than what we do in the Med. Is there any particular reason for doing it this way or is it just convenience ?
Now I understand why 'checking' or 'testing' the mooring buoy is such a bad idea in the US. In the Med you can test as much as you like but that block of concrete is not going to move. Perhaps the chain may break but that is something you cannot predict.
 
2 tidbits that seem to echo most of my experiences with moorings......

From.... Setting Your Own Mooring Buoy | Capt. F.K. Lanier & Associates, LLC Marine Surveyors and Consultants Chesapeake, Virginia (757) 287-3770

"Deadweight anchor selection must be based on “immersed weight” rather than air weight – concrete’s immersed weight, for example, is roughly half of what it weights out of the water, which can translate to requirements for some substantially large anchors. A deadweight anchor will need to be roughly 10 times as heavy to do the same job as a comparable, well-set mushroom anchor."

"The holding power attributed to this type of mooring is impressive – Earl Hinz states in his book “The Complete Book of Anchoring and Mooring (Second edition)” that a properly set 150-pound screw anchor with a 1 ¼” shaft has exhibited holding power equivalent to a 40,000-pound concrete sinker."

This was interesting too.....

www.boatus.com

Everyday Moorings

A quiet evolution over the past two decades has improved two key elements of the mooring system. Have you given your mooring a makeover yet?
www.boatus.com www.boatus.com

"In the last year, all of the incidents of moorings being dragged in the claim files involved either mushroom or deadweight anchors."
 
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I believe that WA State DNR requires the use of helix anchor mooring systems for private moorings. They only issue permits for non-commercial, non-residential (ie no live-aboard), non-transient vessels of 60' or less. They have a specific requirement for the mooring ball and will allow two designs for the rode. The first is an all rope rode using a floating line. The second, and preferred, is a rope rode with a midline float and a short chain section attached to the buoy. This is to avoid a line or chain from dragging on the bottom and disrupting habitat. Most home owners that I know who have permits for a buoy, have them installed and removed each year. I think the permit is good for 5 years.

There are different requirements for cities and commercial mooring fields I believe.
 
The block system mooring typically has a length of line shackled to a length of chain which in turn is shackled to a heavier length of chain which in turn is shackled to the eye installed in the block. The likely points of failure are the articulating shackle joins wear points. The closer to the block the less movement, so the point of failure is likely to be higher in the rode.
Returning to the original question, most don`t have the capacity or perhaps the inclination for a survey dive so load testing seems the only readily available way to gain some assurance of integrity.
 
Jklotz said:
Being a newbie, and having read the recent thread of the guy who lost his boat to a failed mooring buoy in the BVI, I have a question. What is the proper way to assess the safety of a mooring buoy? Lot's of places won't allow you to throw out an anchor, so, if you want to stay there, you don't have much of a choice. What can you do to make sure your still secured if the wind and waves pick up in the middle of the night? Is there such a thing as a proper procedure for this?
Click to expand...
Not sure about the mooring balls in Washington, etc. but in the BVIs some are pretty sketchy. We pulled into Cane Garden Bay one Christmas Holiday and the Bay was a lake it was so calm. Middle of the night (of course) the North swell came in and waves were breaking on the reef and then again on the shore break. We were pretty close in and just where the second sets were breaking so I turned on the engines and kept as much tension off the mooring ball as possible and our bow into the surf. At first light (when we were covered by insurance again) we departed through the channel in the reef (with surfers in the waves) and tucked into Soper's Hole to get some sleep. There are a few "soft groundings every year in the BVIs from similar situations.
 
I was anchored at Cambridge Cay in the Exumas (Bahamas) when a large, approx 100 foot yacht picked up a mooring near me built for 60 foot boat max (the crew did not know what they were doing). Before they had everything situated I noticed the boat moving more than the mooring would allow, and toward a shallow bank. I got on the radio to notify the captain that he was dragging the mooring. He dropped the mooring line and left the mooring field. I snorkeled the mooring. It had a helical anchor with a 1.5" x 1.5" hardened steel bar that sheared clean off at the sand line. The boat had dragged the ball, chain, and part of the anchor about 150 feet. The captain and crew seemed clueless.
 
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