Need a Bomb-Proof Mooring

[seadoggie]

Our Hunter 40 survived Irene with 3 anchors in a soft bottom of 8' depth. Irene was a milder storm than predicted, and I have to admit, I was concerned leaving her like this. She weighs 19,500 lbs., and I am not sure what forces are involved at Hurricane type winds. I do know they are considerable. With shift in wind direction, our initial even pull of anchor rode became less effective as a unit, and more reliant on an individual anchor. I am interested in trying to place a mooring in this soft bottom, using possibly a group of pyramid anchors and chain. Each link could be the "weak" one. I would appreciate some ideas on size of the chain needed, # and weight of pyramid anchors, and what type of strong shackles or connections to use. Many thanks, Eric

 

[n624ma]

Have you looked at Helix moorings ( http://www.helixmooring.com/ ) combined with a Hazelett ( http://www.hazelettmarine.com/ ) elastic rode?

I'm moored in Groton Ct and when Irene came through I went down to look at how everyone that was still in the mooring field was doing. (I hauled out for the storm)

We had one boat on a Helix/Hazlett combination and although the wind wasn't too bad the waves were high, short and steep. The thing I noticed was when this boat hit the end of it's travel with a wave there was no whipping motion from the roller furler foil on the head stay. The other boats around it had a distinct whipping motion as they came tight on their chains. So the elastic rode was doing it's job and the helix is about 12 feet into the bottom so dragging isn't an issue.

Not a cheap solution (I also have this system and it was about $4000.00 installed) but a lot of peace of mind.

 

[CarlN]

+1 on the Helix. It makes conventional moorings (including the pyramid) look silly by comparison.

Next most important - by far - is to use a shock absorbing pennant and protecting the pennant from chafe. Nylon line is much more chafe prone than polyester or some of the newer fibers. Yale makes a great pennant with an outer chafe resistant layer. Another alternative is to make up a multi-part pennant where the section at chafe areas like the chock is chain or wire rope.

Use a braided not twisted line for the pennant since high load cycling of twisted line can cause it to overheat internally and melt.

Finally, try to think of a way to keep your boat from yawing. As a boat get's sideways the area exposed to the wind is much greater. The "jerk" as the boat reaches the end of the swing can be several times the force of the boat bow into the same wind. Jordan (of Jordan Serices Drogue) wrote an intersting paper that modern boats would be better off moored by their stern in storms if there is protection from large waves. Interesting reading but I've never quite dare try it.

http://www.jordanseriesdrogue.com/D_14.htm

Carl

 

[higgs]

We used railroad wheels which, once settled into the bttom provided a very secure mooring.

 

[seadoggie]

I have looked into the helix anchors. The largest ones have to be put in by professionals, the smaller ones you could possibly put in yourself, but would need to put multiple small helix anchors for our boat. I am afraid that with cost to move a barge many miles to our marina area would be prohibitive. Thanks for the input! Eric

 

[Ross]

I have often thought that an old farm harrow or a six bottom plow would make a very secure attachment to the bottom. Of course they weigh about a ton or more.

 

[CarlN]

How deep is the water at your mooring? I know a fellow who cranked in a good size helix from the deck of his boat using a long pipe extension after securing it with anchors in multiple directions. I think he also had another boat rafted with the helix pipe between. The bottom was fairly soft - but I assume the same is true for you.

Carl

 

[Gail R]

Mooring installation costs

I have looked into the helix anchors. The largest ones have to be put in by professionals, the smaller ones you could possibly put in yourself, but would need to put multiple small helix anchors for our boat. I am afraid that with cost to move a barge many miles to our marina area would be prohibitive. Thanks for the input! Eric

I'm curious. Where do you usually keep your boat? Up in these parts, we have marinas with slips and we have harbors with permanent moorings. The cost for our permanent mooring - installed - was considerably less than the cost of a marina slip rental for a single season. I think that's a good value, but perhaps I'm nuts.

Do-it-yourself moorings are frowned upon here. Our harbormaster requires a certificate from an approved mooring servicing company every two years. That costs a few hundred boat bucks, but it is still a lot less than a marina slip, and way better in a storm.

We don't mind paying for our mooring and its upkeep. It is what keeps the boat off the bricks.

BTW, our mooring is a big chunck of Maine granite. 5000 pounds worth. It isn't going anywhere.

 

[Cayennita]

In the Virgin Islands, we can do our own, or hire a diver to install sand screws. many people just throw an engine block and chain or whatever they can find. There is no policing. We are trying to get some uniformity.
In my case, I have 2 sand screws, one 100# anchor and one 50# anchor covering the 4 points of the compass. All with chain going to a monster swivel. Two 3/4" lines and a pick up buoy. It has made it to various hurricanes. I dive on my mooring quite frequently and have it serviced if needed. Also I check on my neighbors to make sure that theirs are still ok. 80-85 degree water and 12' depth helps quite a lot.