Unique Way of tying off to pilings in slip to keep boat centered during storm surge

[Montanan]

Originally Posted by clayzone

Doesn't look like the tide rings will work if you are tied up sideways to a fixed dock. Correct me if I am wrong because they look like the easiest solution for dealing with tides.

Beam to quayt / fixed dock situations with large tides commonly favor using a slide scheme on the dock / quay wall [similar to some that are used in locks] and if there is a piling out away from the quay / fixed dock to moor to so as to keep the vessel from contacting the fixed dock and piles that support the dock and / or the wharf wall then that mooring line could benefit from using a sliding mechanism to adjust for the change in water height.

One can fashion a runner line to which you tie your mooring line to. The picture below is of a runner on a ladder which are ladders are common on tall quay with large tide changes so as to allow access to and from the boats at all stages of tide. But a vertical runner can be set around anything where a line can be fixed top and bottom.


Another example of a vertical slide, useful for walls, fixed dock structures or piles. http://https://www.tideslide.com/

[edexter]

Well, in the Mid-Atlantic it's not uncommon to have fixed docks, or some fixed and some floating. In the upper Chesapeake the tidal range is a foot or two except in storms or seiches, fixed docks work (although where we are has a long floating dock parallel to the shore, off of a combination fixed and floating dock coming off of the shore). I just checked Bowley's Bar at the mouth of Middle River where it hits the Chesapeake, and the projected tidal range this weekend is about a foot, lol. Where I grew up on Long Island Sound, the tidal range was 8 - 10 feet, sometimes 12, and fixed docks were a real pain.

[19thol]

We are just off the gulf in St.Pete fl. so the tide doesn't really change all that much for the most part. Maybe 2ft. on average. But we've been through a couple of hurricanes with no problems. Our bow lines are tied off low on the dock, and our aft lines are crossed and tied off high on the pilings. So as the tide rises the boat drifts forward as the slack is taken out of the bow lines, and when the tide recedes, the boat drifts aft as the slack is taken out of the aft lines. Been working for three years now, think it'll work.

[Montanan]

Originally Posted by 19thol

We are just off the gulf in St.Pete fl. so the tide doesn't really change all that much for the most part. Maybe 2ft. on average. But we've been through a couple of hurricanes with no problems. Our bow lines are tied off low on the dock, and our aft lines are crossed and tied off high on the pilings. So as the tide rises the boat drifts forward as the slack is taken out of the bow lines, and when the tide recedes, the boat drifts aft as the slack is taken out of the aft lines. Been working for three years now, think it'll work.

Brilliant!

Do you also use spring lines, or does this configuration work to resolve the boats travel fore and aft?

[ranger58sb]

I meant to mention there are several systems: Pile Rings, Tide Minder, Tide Rings, Tide Right, Tide Slide, Slidemoor...

-Chris

[stubones99]

How about these pilings?
Portland Oregon marina


https://www.boonesferrymarina.com/

[Montanan]

Originally Posted by stubones99

How about these pilings?
Portland Oregon marina


https://www.boonesferrymarina.com/

Darn impressive! Ready for rising sea levels and / or a tsunami.

That is exactly what I had envisioned as to appropriate length of pilings so as to avoid overtopping.

Heck even Noah's Ark would fair well in a marina like that.

Hurricane storm surge, Bring it on!

[RonSurf]

My boat was moored in California before moving to Florida. Here they drive pilings into the mud. Typically 5 or 6. Hopefully, all marinas will eventually use floating docks like California with very tall pilings in areas that experience hurricanes with storm surge. The Chilean Earthquake sent tsunami waves into California with large changes in water depth. That was something to watch. The authorities predicted 1 to 2 feet of surge. It was more like 4 to 6 feet every 20 minutes, rising and falling.

[RonSurf]

I am finding that I don't need spring lines. I leave them on to use when pulling the boat over to board the boat. You only need 4 dock lines to center the boat.

[RonSurf]

I am finding that I don't need spring lines. I leave them on to use when pulling the boat over to board the boat. You only need 4 dock lines to center the boat.

[Hardhead]

Originally Posted by RonSurf

I wanted to share something that came to mind at the begining of 2018 Hurricane Season. I wanted to create a way to tie off to pilings and keep the boat centered at all points during surge or extreme tidal swings.

Disclaimer: This is still experimental and could use some engineering calculations. This should only be used with the advice of a professional to be sure that it will keep your boat safe during storms. I will not be held responsible for any damage incurred for reasons of too many variables including boat sizes, dockline strengths, and surface area of structures above the waterline that create forces that challenge the physics of keeping a boat tied safely, which precludes having a one size fits all solution. This is why I recommend seeking a professional's advice before installing this in your boat slip.

The Set Up:

Tie a block using dockline and clove hitch to the top one foot of each piling in your slip.
Repeat the process at the lowest point at water level to the bottom of each piling.
Now, run a dockline from your starboard bow deck cleat to the top block on the piling and run it through, then down through the block on the same piling at water level, then back up to your bow cleat to be tied off. This forms a triangle.

Repeat the formation of triangles on all of the other pilings, beginning at each deck cleat, through the 2 blocks and back to the deck cleat on the boat.

Cool physics:

As long as your deck cleat height is between the upper and lower block on the piling, your boat will travel in a straight line up and down with tides. If it exceeds the top or bottom block, you will have to let out some line on the deck cleats. If a storm is arriving, tie off the boat to allow movement side to side to reach close to but not getting closer than a foot or so from pilings to allow for stretching of docklines during wind gusts or surge. Theoretically, the boat should stay centered even if the tide takes your boat above the tops of the pilings, but not too far above. Again, check with a dock neighbor with an engineering degree to be sure your boat will be safe.

Cost:

3 times as many docklines as you have now on your boat.
2 blocks per dockline that form each triangle. This means 16 blocks for 6 pilings, including 4 spring lines. With at least $30.00 per block, this will cost $480.00. Use the heaviest block that you can. Breaking Load of docklines are 7,000 to 10,000 lbs.
Some blocks range in the 3,300 to 5,000 lb. Range. 2 per triangle.
Adding the cost of docklines, at least $480 at $20.00 per dockline. This is for one dockline top and bottom of the piling to secure the blocks, and one to run from the boat, through the blocks and then return to deck cleat.
Not cheap: $960.00

I used this set up during the 2018 hurricane season. Winds here were up to 55 mph. I have not tested this in winds greater than that at this point. It gave me peace during winds and surge.

I enjoy this set up. It took two sleepless nights to finally come up with this, but now I don't worry about the dinghy on davitts hitting a piling, or rubbing against side pilings with tide changes.

I hope this works for you.

Ron
Biology Degree
Teacher of Science Certificate

Sounds like a damn smart idea to me. This rig also seems like it could be used much more easily with shared pilings - if your dockmate already has the piling tied up with ropes, preventing a ring slider system. I'd use it.

[RonSurf]

A better way to tie off and cut cost down to approx $500.00 is to use 2 blocks per piling, top of piling and at water level as before, but use only long dock lines, one per piling. Run each dock line from your deck cleat on boat, through lower block, then through upper block and back to deck cleat on boat to tie off. This forms a triangle that moves freely through the blocks. You won't need spring lines, but I keep one on to pull the boat over to the dock. You can tie the boat off in any position in the slip, close to dock, centered in slip or away from dock.

You will need 8 blocks, line to secure 8 blocks to pilings, and 4 long dock lines. Also one or two spring lines to pull boat over to board.

[fitzpatl]

(this may be stale thread but the topic is useful) There are a lot of systems available (as mentioned earlier) but only Tide Slides work well in a setup where outpiles are on one side and fixed height pier is on the other. However, tideslides are insanely expensive (by the time all hardware is in, for 5' rail and 40' boat, about $8K).



@ronsurf I like your basic idea modified by @bobmc suggestion. Fix the line to top and lower end of the piling, thread the line through a block to ride up and down. Fix a ring to the block, then fix a dock line to the ring on the block and tie it off at each cleat. When away, leave the whole arrangement of dock lines et al hanging on a peg at the dock.

[GordMay]

Greetings and welcome aboard the CF, fitzpatl.