Stuck in the mud

[Project_Mayhem]

The yard is having a lot of issues under it's new management. I ran into the new director and he mentioned that they had a boat that's stuck in the mud due to low lake levels. How would one go about resolving such an issue? Obviously if it was by a crane, they probably would've just used that (assuming it wouldn't put too much stress on the keel/hull joint).

This is post is intended to debate an interesting problem, not actually solve it

 

[jssailem]

It is the boat and not the owner. Two different problems. One booze might help. Break down barriers.

The boat would be more challenging.
Asking the question just a little or up to the gunnels.

• Applying physics one might lighten the boat to float it higher.
• I’d imagine one could try to heel the boat to get the keel free and float it on its side.
• They raise boats off the bottom of Lake Michigan by attaching air filled bags. This might get the hull a foot out of the water freeing the keel from the mud.
• If the keel is detachable, one might undo the bolts and see if hull can float free.

Or leave it as a decorative message to all boaters: “Do not do what this guy did“

 

[dlochner]

The water levels on the Great Lakes are closely monitored. The USACE publishes the data as do other agencies including the St Lawrence Seaway Commission. They are also pretty good at predicting levels out a month or two. Since the marina seems to be in a marginal area in terms of water depth it would be wise to closely monitor the data. There is also a lot of historical water level data online.

The boat owner should also monitor the data especially if they have a deep draft boat. Boats with deep drafts should be moved to deeper water in the marina or the owner move the boat to different marina.

To get this boat out, first lighten it. remove as much weight as possible; remove sails, gear, empty water tanks. Try heeling the boat in the slip and sliding it out. Since local water levels in the Great Lakes can be affected by wind, try moving the boat when wind is blowing water into the marina.

Detroit District Water Management

water.usace.army.mil

 

[duality]

which yard?

 

[Scott T-Bird]

We had a noreaster storm last Thursday that pushed water into the bay and our marina and raised the water level to within about 6-inches below dock level. Soon after, a strong west wind pushed the water out and our keels where resting on the bottom. Topsides were exposed about 6" below normal waterline on Saturday morning - just about everybody in the marina was stuck. The total swing was about 54 inches! Our normal tidal variation is around 6 inches. Luckily, it won't be long before sea level comes back to normal!

 

[ShawnL]

I've actually seen it on Keweenaw Bay in the UP, on Lake Superior (we called it a seiche). There's a stretch of road with the lake / bay on one side and a deceptively deep marshy area on the other. On one trip you could see the 'tide' coming in with quite a bit of speed and the beach being swallowed up. About an hour later, on a return trip the opposite was happening. The marsh was emptying back out. No real wind to speak of, at least not enough that we noted it. Very cool to witness.

 

[capta]

Do not try to pull from the top of the mast. Please. In my experience, it dismasts the boat more often than not.
The suction of the mud will add to the difficulty in refloating her again.

 

[Project_Mayhem]

Would pulling the hull with a crane put a lot of strain on the keel to hull joint or sub frame if the keel is suctioned to the muddy lake bed?

 

[dlochner]

Would pulling the hull with a crane put a lot of strain on the keel to hull joint or sub frame if the keel is suctioned to the muddy lake bed?

Possibly, the pull would need to be slow and steady. Once the suction is broken it would come up. It would also depend on the nature of the mud. Some mud is thick and sticky other mud, especially if it is full of organic matter, is pretty soft and almost liquid. The suction can be broken by injecting water along side of the keel. Attach a garden hose to a section of pipe and stick the pipe next to the keel and turn the water on. The water pressure will erode some of the mud and reduce the suction. Pilings are set and removed using this technique.

 

[jssailem]

What type of keel?
Fin, winged, etc?
How deep in the mud?
Will the crane be pulling up vertically or from a horizontal angle?
What type of lake bottom? Silt, clay, or sand?
Is the keel bolted on or molded into the hull.

 

[rgranger]

Could you run a firehose down to the union of mud and hull and hydrolically lift the boat? The boat is meant to float so once you get a layer of water between the hull and mud, it should separate.

 

[shemandr]

In my experience fin keel boats tend to lean over when they are left in too shallow water by tide or seiche. So I've never witnessed one that got stuck in the mud. In a slowly lowering lake situation it may be different. Normally the wave action causes the boat to wiggle enough to burrow a depression around the keel and suction does not develop. This was common in a marina in New Suffolk, NY. You could see the holes when the Winter winds would blow the water out.
Wing keels might be different. But I had one, which was occasionally on the bottom, and it didn't get stuck.

 

[jssailem]

It is not clear at what state has developed. Is the boat lashed to. A dock and still floating? Is the boat stuck high and dry?

 

[jssailem]

Up here in the PacificNW the tidal change is dramatic. 10 to 12 feet is not abnormal. On those extreme low tide days some of the boats on our dock are “STUCK in the MUD” as there keels are buried in the silt from years of river/tidal flushing. We play the game Stuck - Not Stuck as we walk down the dock pushing the bow of the boats to see if they move. I am glad to own a boat with a 4.5 ft 2/3’s long keel draft not a plus 6ft fin keel and am closer to the fairway of the marina where the mud bottom accumulation is less.