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Old 06-04-2009
NCC320 NCC320 is offline
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Floating vs. Fixed Piling Dock: Just to confuse the situation, I really think fixed piling piers are better for hurricanes because of the storm surge and wave action which accompanies these storms. Generally, floating docks rely on just a few large steel pilings to hold all the floats and all the boats. That's a lot of force pulling on the these pilings when the high winds and waves hit. With the fixed piling piers, there are usually lots of somewhat smaller pilings with each boat clinging to a few of its own. Normally, the cross section area of these pilings (i.e. the bearing surfaces vs the mud/sand bottom) will cummulatively be greater for the fixed pier than that of the few steel pilings of the floating pier. Then, there's the possibility of floating piers floating off the pilings due to storm surge. Of course, with fixed pilings, your lines have to be tightly secured to the pilings so they also don't work off the pilings when the surge is present, and there has to be enough room in the slips so that you can accommodate the upward motion of the boats due to surge. Also, with most floating docks that I've seen, there are relatively few cleats or other tie points tol which to connect extra lines. With the fixed piling piers, there are usually more points to tie to and you can tie directly to pilings vs. to cleats, which have a tendency to pull out. I am a great believer in tying as many lines to piers as you can, so as to spider web the lines (watching for line to line chafe). My normal tie up for these storms is 26 lines to 8 - 10 different tie points on both the pier and the boat. It's important to tie the lines such that they tend to load up evenly so a particular line or tie point is not over stressed. If you tie across adjacent empty slips as I do, some lines will be longer than others. Put an initial tension on these longer lines, since the long lines will stretch easier and could result in uneven loading during the height of the storm if not prestretched a bit. Typically, all my lines are 1/2 in. nylon for a 32 ft. boat. In my opinion, if you use mixed sizes of nylon, you should tie all sizes as if they were a common size (that's at odds with another post on this thread), but if you mix nylon with polyester, or use old halyards (low stretch) as additional backup lines, you should give some consideration to the variations in amount of stetch each type will have to avoid overstressing a given line. Finally, while the stretch of nylon is good in absorbing shock, it can also be bad if the stretch is enough to let you boat bang against the pier or piling...keep in mind that the stretch under hurricane conditions is a lot more than you see when you are preparing the boat for the storm. Lastly, in my experience, the boat, if it is exposed to wave action, is going to be bucking up and down wildly, so put the lines on and adjust them before the storm. Wish the boat well and seek higher ground for yourself. Keeping boat at the docks will work only if your lines can accommodate the surge, and in some places that's not possible. In my area of NC, about 1/3 of boats are pulled out for storm (but the storage areas are low lying), 1/3 go to anchor bouys or anchor out, and 1/3 stay at the pier. Damage usually occurs with each strategy, with no one of these being clearly the best in this area. Just my thoughts.

Last edited by NCC320; 06-04-2009 at 01:51 PM.
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