October 29, 2022

Get Out of the Marina!

The post mortems are coming in for Hurricane Ian, and from a boating perspective the lessons are clear. Get well out of the path, if at all possible, and secure your boat well away from others and on a mooring or anchors. The many scenes of wrecked marinas clogged with sunken boats perfectly illustrate the problem with relying on fixed docks. Very few marinas are designed to handle storm surges of 10-15 feet above normal high tides, and even if they are you are completely at the mercy of how well the boats around you are tied up. Once one goes the domino effect takes over.

However, a well-designed mooring and/or anchor setup can easily manage the storm surge if anticipated. Extra scope will be needed, along with extra lines and chafing gear, but I would much rather have my boat pointed into the wind and secured by the strongest cleats and lines from the bow. Pointing into the wind will vastly reduce the strain on everything.

Of course, this assumes you have a mooring or anchors with sufficient holding power. Typical mushroom anchor moorings or heavy blocks, as are frequently used, are not up to the task unless they are deeply buried in thick mud. With a sandy bottom, that is unlikely. Helical screw type moorings can provide the needed holding power, and these are available in places in Florida like Boot Key Harbor on Marathon in the Keys. By all accounts, the moorings there have held through hurricanes, with the weak link being the lines securing the boat. Usually, line failure is due to chafe onboard.

In major hurricanes it is wise to also put out your best anchors in support of your mooring. In Hurricane Bob we put out two Fortress anchors to help the two-ton mooring block we were on. The anchors were easy to set from the dinghy using long lengths of nylon line, and after the storm it took me most of the day to winch them out of the muddy bottom. Judging from how hard they were buried, both anchors provided significant holding power to the mooring rig. During the same storm many moorings were dragged ashore, in most cases due to insufficient scope added for the storm surge. However, many typical moorings are not well buried, undersized, and may not be in the best bottom for holding power. Unfortunately, harbor regulations often guarantee moorings are not well buried, due to frequent inspections that necessitate pulling the mooring completely out.

It is the topic of another post, but I have had complete success using large diameter PVC water tubing slid over mooring lines. Some reports indicate a possible problem with lines overheating and failing when encased in PVC, but I have not seen evidence of this after several hurricanes, a few tornadoes, and numerous gales. Other people have used and prefer sliding tubular nylon over your mooring/anchor lines. I too have tried this and it works well under ordinary storm conditions, though I believe the PVC provides the ultimate protection.

Another problem is how to best route the lines to your boat so that they contact as few points as possible to avoid chafe in the first place. Anchor rollers on bowsprits are vulnerable to being leveraged down or up and off. Plus, bobstays can act like hacksaws on your lines. Personally, I like multiple lines leading direct to deck-edge cleats or over smooth surfaces to cleats. Anchor rollers can work if very short and mostly on deck, and of course securely bolted down. Keep in mind that your boat's bow may be pitching down as well as up! In other words, don't depend on a downward pull on the line to keep it within an anchor roller. There must be something to prevent the line from being pulled up and out of the roller. On our boat I have also installed a bow eye near the waterline as an additional strong point.

It is a good idea to try to balance the strain by using multiple lines to the anchors and moorings, and then run lines from one cleat to another, if possible. In some cases, it might make sense to run lines back to mid-deck cleats or possibly the mast, if keel stepped.

Note I haven't mentioned the use of chain. It should not meet your deck under strain! In other words, make sure all chain is overboard with long lengths of nylon line leading back to the boat, or use long and very strong nylon snubber lines. Some friends once had their anchor chain jump the roller in a storm, and it began to saw down through the deck and hull as the boat pitched. The skipper was badly injured while trying to get the chain back into the roller.

So, how much wind can a good mooring/anchor setup take? During Bob, as described above, winds reached around 100mph with a storm surge of over 6 feet. Where we were only three boats broke free from their moorings: two were due to chafe and the third boat pulled the mooring straight up and floated with it to shore. Put out plenty of scope! Winds of 150mph with 10-15 feet of storm surge are another matter, but some moorings in Ft. Myers Beach did hold despite the vast damage there. I look forward to learning more about what happened to moored vessels there, in Punta Gorda, and in the Keys. I suspect that very few boats would have deck gear able to withstand the strain of Hurricane Ian winds, which is why running away is so important in the first place. But, if you can't escape the path, get out of the marina!

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