Best Hurricane Tie?

Looking for some advice on tying up a 44' trawler style boat in preparation for hurricane.

We're in a floating dock system within a fairly well protected marina.

I've heard some folks recommend tying very tight to dock, but my sense is that it will fair better tied in the dead center of slip.

Any advice is appreciated.

Either way your depending on cleats..>>>Dan

Here is a thread on some tips for boat survival

https://www.trawlerforum.com/forums/s58/cyclone-preparations-marina-31898.html

In general, if the docks are adequate to withstand the storm, here are a few guidelines I'd follow for any heavy weather tie-up:

• No short lines. So no short breast lines bow and stern, except maybe left slack as a backup line. The longer the lines are, the more stretch they'll have and the better everything will ride with less risk of shock loads causing cleat failure.
• Use all available cleats. Lay out your lines to maximize the number of cleats on the boat and dock that are in use to spread loads.
• Avoid single points of failure. Tie so that any single line or cleat failing won't put the boat in danger (particularly dock cleats if they're of somewhat unknown strength).
• No excessively slack lines. Too much slack lets the boat build momentum and increases shock loads. Only give as much slack as needed to handle water level changes and to get the boat to ride nicely.

Ideally, if you can tie to both sides, I'd put the boat in the middle of the slip, tied as tightly as reasonable. That'll also make it easier to spread the load to more cleats. And consider dropping the anchor as well.

I really like the idea of dropping anchor. If a tender could take each boat's anchor out 75 yards or so, at different angles, and the owner's winch them tight, that could add a lot of support to a string of floats and take some stress off the pilings.

It might make sense to attach a separate line and buoy to each anchor for post storm retreival if the anchor lines fail.

Sorry folks but floating docks are the problem. How do I know well let’s just say I’ve been involved in dozens of these scenarios. Cleats and lines or ground tackle won’t save your boat if the docks float over the tops of the pilings. Not sure where you are but if you’re in a deep harbor with Southern exposure the tidal surge is like a giant funnel where water is driven into a narrowing harbor resulting in an tidal surge elevations that grow to unbelievable heights. Nova Scotia, being a predominant Southern exposure is in for big trouble with Fiona. Most docks and piling heights rarely are built for such extremes. They are too short. Get out of there if the hurricane is going to land or pass within its rings to the South, or on you, since that is the wrong side that pushes most of the water. I’m sure other posters will tell you otherwise but don’t say I didn’t warn you

Rick

garbler said:

Sorry folks but floating docks are the problem. How do I know well let’s just say I’ve been involved in dozens of these scenarios. Cleats and lines or ground tackle won’t save your boat if the docks float over the tops of the pilings. Not sure where you are but if you’re in a deep harbor with Southern exposure the tidal surge is like a giant funnel where water is driven into a narrowing harbor resulting in an tidal surge elevations that grow to unbelievable heights. Nova Scotia, being a predominant Southern exposure is in for big trouble with Fiona. Most docks and piling heights rarely are built for such extremes. They are too short. Get out of there if the hurricane is going to land or pass within its rings to the South, or on you, since that is the wrong side that pushes most of the water. I’m sure other posters will tell you otherwise but don’t say I didn’t warn you

Rick

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It's a good point, but not all floating docks are in that same boat. We've been at a few that have new piles, looked to be approx 18' taller than water level... specifically due to surge potential. And then some are better protected than others from direct wind.

Just saying not all floating docks are created equal...

-Chris

rslifkin said:

[*]No short lines. So no short breast lines bow and stern, except maybe left slack as a backup line. The longer the lines are, the more stretch they'll have and the better everything will ride with less risk of shock loads causing cleat failure.
[*]No excessively slack lines. Too much slack lets the boat build momentum and increases shock loads. Only give as much slack as needed to handle water level changes and to get the boat to ride nicely.

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FWIW, we've had some success adding rubber snubbers on lines that ended up having to be short... e.g., crossed stern lines...

I think I'd now be inclined to do that with bow lines, too...

-Chris

ranger58sb said:

FWIW, we've had some success adding rubber snubbers on lines that ended up having to be short... e.g., crossed stern lines...

I think I'd now be inclined to do that with bow lines, too...

-Chris

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Yup, that's a good suggestion. I've also thought that for shorter lines, you could double them. 1 line a size smaller than you'd typically use and of a fairly stretchy construction (3 strand or 8/12 plait). And then a larger line left with a little slack to limit how far the first line can stretch (if it doesn't get over-stretched it's less likely to fail). And the larger line will take over if the first line does fail.

I think it is hard to trust floating docks. I don’t know how many pictures of destroyed marinas I have seen where boats are broken loose that are still tied to a large section of dock. I would always tie to the pyles in the center of slip with the longest lines possible… especially spring lines… leaving extra for the marina to let out more as needed. That said, if the marina’s pylings are not tall enough for the tidal surge and the possibilities they will lift over… well, you might want to explore other options.

Nobody here can, or should, tell you exactly how to tie up for a storm. If the marina has been thru storms before, they are a better source than anyone. Every situation and setup is different. We have fixed docks and tide slides… another marina near us has floating docks and extremely tall pylings. Some require boaters to vacate, others are “hurricane holes”. You have to use your best judgement.

I agree w ranger 58, not all floating docks are up to the strain of a hurricane.


I have had success/luck weathering 6 direct hits since 2004. What's worked; the middle of the slip like a spider in a web; chain around the pilings (not really applicable on a floating dock); anchors to keep it from being blown into the dock(crossed); all canvas down to reduce windage (it will be removed for you) and all hatches/lids/ doors secured; batteries charged; shore cord stowed, pumps checked, bilge clear of any potential clog. (the boat WILL be ROCKED)(prepare as if going to sea)

If the docks are wood and less than confidence inspiring and have many boats pulling at them, consider finding a canal or cove to have her ride it out in (WITHOUT YOU ABOARD)
I anchored one boat out in a narrow section of the ICW (Hurricane Francis then Jean a week later) on 4 oversized danforth style hooks set opposing each other and all lines led to the bow, so she could face the blow.


Use your sense common sense and good luck!

Back in 1982, as I recall, I was working for a surveying office in Wilmington, SoCal when we got a call from a large Broker from Atlanta asking if this office could put three to four surveyors on a large Cat Loss (Catastrophy) for perhaps two to three weeks. Well the owner took the job and what a job. Heavy Arctic storms were hitting the coast extending well South of Pt. conception into SoCal with waves unlike anything anybody had seen and they hit hard. The big rock breakwater known as Angels Gate entering L.A. harbor had actually had a number of five to six ton rock knocked loose. Old time ‘ rock slingers ‘ from Local 2375 many of which worked and built the jetties said they’d never seen anything like it.

These waves and the accompanying surge swept over the Redondo King Harbor breakwater resulting in unbelievable damage. The King Harbor marina had just been rebuilt a few years earlier using two highly competent engineering firms who along with Army Corps figures built all elevations factoring highest water marks. In doing so they reportedly used a base line established from max king tides plus some fudge factor percentage for big storms.

Well the floating docks with moored vessels floated off the tops of the pilings along with service risers, conduits and all. About eight to ten vessels were driven right into a line of businesses along the boardwalk. These boats were pushed right through the windows and front walls. Your Grand Banks 36 could pick up a Pita Pocket from the restaurant below the bow. Six years later I understand it happened again but I was no longer there.

Rick

I was tied to the center of my slip on the newly constructed floating dock at Burnt Store Marine, FL.

2 lines did fail during Ian, in each case the 'doubled up' line was tied slightly looser and held. The entire dock failed. My boat did bring at least one of the pilings with it to the mash up.

So double all lines with some slack, more slack in secondary and search for the mash up after.

About double lines:
It's important to stop surging as it's hard on both dock and boat hardware. So when rigging for a storm, I use the normal lighter lines to slow the boat down. These stretch more to try to stop the boat without shock loading hardware. The second heavier line comes into play to stop the motion. When rigged correctly, the first one stretches but not to the point of risking breakage. The second is the final stop. Whenever possible, don't have both lines sharing boat or dock hardware. Also remember that 3 strand twisted nylon has more linear stretch than double braid nylon (for the same sizes and quality of components).

As far as floating versus non floating docks, I have no problem with either. I wouldn't pick one over the other. For me, wind and wave block are more important than dock type.

Finally, one of the best situations is to be able to move to a larger slip. My charter boat was in a marina basin with some wind block and absolute wave block. Many of the big sport fish had to haulout for insurance requirements. So I would move my 35' boat to a 60' slip. Centering the boat in the slip with all double lines and plenty of slack so that the boat could move and rise / fall with the storm surge took time. The result was no damage or piling burns as it was kept safely away by the lines.

Ted

This to me and has been posted above....it depends.

In the long run, tying alongside almost guarantees rub damage but if in the middle of the slip and line faiure allows the boat to meet a dock or other boat, the damage can be much greater.

One major problem with tying tight on a floater is line lead. Too often its pulling up and breaks the cleat horns or pulls the cleat free.

psneeld said:

This to me and has been posted above....it depends.

In the long run, tying alongside almost guarantees rub damage but if in the middle of the slip and line faiure allows the boat to meet a dock or other boat, the damage can be much greater.

One major problem with tying tight on a floater is line lead. Too often its pulling up and breaks the cleat horns or pulls the cleat free.

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That last bit is why on any floating dock, I follow the rule of "no short lines". The longer any line can be made, the better the lead angle gets. And the more stretch you get, so you can tie the boat tight and also get good shock absorption to reduce stress on the cleats.

I agree no short lines. It's about the lines ability to stretch. Typical double-braided nylon line can stretch up to 20% before it's tensile strength is impacted. So this is really only about 1.2" per foot.

But the other side of the coin is reducing slack. Too much slack and the line gets shock-loaded each time the boat accelerates, then reaches the limit of the line stretch.

This puts us into another paradox. On a fixed dock, how do I keep the boat from hitting the dock or pilings during high tide with storm surge, but also keep the boat from hanging on the lines at extreme lows or when storm surge blows the water out instead of in?

Shrew said:

I agree no short lines. It's about the lines ability to stretch. Typical double-braided nylon line can stretch up to 20% before it's tensile strength is impacted. So this is really only about 1.2" per foot.

But the other side of the coin is reducing slack. Too much slack and the line gets shock-loaded each time the boat accelerates, then reaches the limit of the line stretch.

This puts us into another paradox. On a fixed dock, how do I keep the boat from hitting the dock or pilings during high tide with storm surge, but also keep the boat from hanging on the lines at extreme lows or when storm surge blows the water out instead of in?

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Long lines help with that last scenario as well. If everything is a long spring line at a shallow angle, they can absorb more height change while still keeping the boat held in place (as the height change causes less angle change on a longer line, so less slack is needed).

Stretch-wise, you don't want to load a line above about 20% of breaking strength. At 20% load, most 3 strand, 8, or 12 plait nylon lines will stretch 10 - 12%. Double braid nylon will typically stretch about 5 - 6% at the same load. The longer the line, the more stretch you get, so the "no short lines" rule is more important if using double braid.

rslifkin said:

Long lines help with that last scenario as well. If everything is a long spring line at a shallow angle, they can absorb more height change while still keeping the boat held in place (as the height change causes less angle change on a longer line, so less slack is needed).

Stretch-wise, you don't want to load a line above about 20% of breaking strength. At 20% load, most 3 strand, 8, or 12 plait nylon lines will stretch 10 - 12%. Double braid nylon will typically stretch about 5 - 6% at the same load. The longer the line, the more stretch you get, so the "no short lines" rule is more important if using double braid.

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Please go back and re-read my statements. You're correctly points not made.

What are everyone's thoughts about tying up to palm trees?


I feel pretty good about my setup, though it is not perfect.


My slip is well up the St. Lucie river, just east of I-95, then about 2 miles up the South Fork, which is narrow and winding, then in a 50' wide canal. I'm normally side tied to a continuous fixed dock. Most of the canal is Grand Bank's HQ and boatyard, they generally have only a few boats in the canal, and a re great to work with. For storms, we work together and spider web the boats in the middle of the canal. I use 16 lines from 7 attachment points on the boat (3 cleats each side plus the samson post on th bow). I spread the lines to various spots on shore, some 16" cleats set in the concrete seawall, some pilings and some very large coconut palms.


I've never felt great about the palms, but my dad just came through Ian in Fort Myers on a canal off of the Caloosahatchee river, he had 10' of water and winds well over 120, God knows what the gusts were. He lost oaks and other trees but all of his mature palms survived, didn't even lose their tops in most cases. It makes me feel better about my chances in a big storm.

Palms (coconut trees) have good root systems and flexible trunks to withstand tropical storms. There fronds often break off in the strongest storms, further reducing their windage. Many that have lost all their fronds, remain alive and grow new ones. All the ones on my property have now survived 4 hurricanes including Irma and Ian.

Whenever tying to a tree, tie as close to the ground as possible. This change the force from breaking the trunk to shearing the base off. The shearing effect requires many time more force and dosen't increase the effort of the tree resisting the storm.

Ted

O C Diver said:

Palms (coconut trees) have good root systems and flexible trunks to withstand tropical storms. There fronds often break off in the strongest storms, further reducing their windage. Many that have lost all their fronds, remain alive and grow new ones. All the ones on my property have now survived 4 hurricanes including Irma and Ian.

Whenever tying to a tree, tie as close to the ground as possible. This change the force from breaking the trunk to shearing the base off. The shearing effect requires many time more force and dosen't increase the effort of the tree resisting the storm.

Ted

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Thanks Ted, that’s sort of what I was thinking. Tying low makes a lit of sense. They hold up better to storms than pilings do in my experience, but they usually aren’t as convenient as pilings.