Intracoastal Marshes; Tidal Docking

[SPC]

I have for a while looking into aged ~35ft monohulls as a low-price entry into cruising, with the hope of one day upgrading to a longer catamaran, once I have the experience to know what I actually would want in a boat (and the savings to operate one). Occasionally, I still look at catamarans, since some of the shorter, older ones border onto the upper end of my current ability to afford.


Every year, I go with my family to a house at the beach in Sunset Beach, NC (33.870, -78.515), which has a floating dock on the marsh off the intracoastal which is intended for small fishing boats. The tides come and go through the day, with the dock resting on dry land at low tide, and floating at high. Whenever the topic of buying a sailboat comes up, we joke about tying up to that little dock to stay for the week.


Of course no monohull (not even a shoal draft) wouldn even make it up the channel. Bigger catamrans would probably be too big to maneuver, and still probably could have too much draft.


So this is my question: would a smaller cruising catamaran, such as a Gemini 105MC (1.5ft draft, 33.5ft LOA, 14ft beam), reasonably navigate to and rest at a dock in the marsh meant for small fishing boats, or is that just as silly? It would have to rest on the sand between tides, like a bilge keel in England, just on a much shorter scale.



While we're at it, I'd love to hear y'all's thoughts on a Gemini 105MC versus, say, a Catalina 36.


Cheers!
SPC

[Davy J]

A Gemini 105Mc most likely could handle the task with the rudders pulled up.

Would I want my personal boat to endure that regime on a daily basis...... No.

A better option might be to install a boat lift. The 105Mc weighs about 10K with a small load. Easily in the realm of larger boat lifts.

Also, don't forget, planning your sailing around the ability to get in and out, based on the tide, will be a big PITA.........

[redneckrob]

Originally Posted by SPC

I have for a while looking into aged ~35ft monohulls as a low-price entry into cruising, with the hope of one day upgrading to a longer catamaran, once I have the experience to know what I actually would want in a boat (and the savings to operate one). Occasionally, I still look at catamarans, since some of the shorter, older ones border onto the upper end of my current ability to afford.


Every year, I go with my family to a house at the beach in Sunset Beach, NC (33.870, -78.515), which has a floating dock on the marsh off the intracoastal which is intended for small fishing boats. The tides come and go through the day, with the dock resting on dry land at low tide, and floating at high. Whenever the topic of buying a sailboat comes up, we joke about tying up to that little dock to stay for the week.


Of course no monohull (not even a shoal draft) wouldn even make it up the channel. Bigger catamrans would probably be too big to maneuver, and still probably could have too much draft.


So this is my question: would a smaller cruising catamaran, such as a Gemini 105MC (1.5ft draft, 33.5ft LOA, 14ft beam), reasonably navigate to and rest at a dock in the marsh meant for small fishing boats, or is that just as silly? It would have to rest on the sand between tides, like a bilge keel in England, just on a much shorter scale.



While we're at it, I'd love to hear y'all's thoughts on a Gemini 105MC versus, say, a Catalina 36.


Cheers!
SPC

The Gemini has an 18" draft with everything up. Go out with a small boat with an 18" stick attached and see if it hits mud at high tide or not.
One thing to keep in mind, having lived at a house with a tidal dock somewhat nearby in southern VA, is how much winds impact tides. It's probably less of an issue there, but we could have several days straight of actual water levels never even getting to the low tide mark with the right winds (and the opposite). If you're only going to be there a week that might be an issue as you could be stranded for a couple extra days. If you live there it's just an inconvenience you learn to live with and you get a feel for how a given strength, length, and direction of wind impacts the tide and can use the weather forecast to do your own tide estimates.

[tkeithlu]

I live with tides at the dock, and used to live with 8 and 9 footers on the Georgia coast. This is doable, but there are even more elements to the PITA.

If the Brits can do it, so can you. A modest cat will sit on the mud, but probably at an angle, so I wouldn't want to recommend live aboard....

This is a fair weather situation. "Residential" floating docks are not adequate to hold your proposed cat in a blow. What's your plan B for when a storm comes along?

Be careful with your choice of bottom paints.

[Yellowtulip]

I'm in the uk, and don't have good charts of that area, but it looks to me like much of our East Coast. A likely solution over here would be to drop a mooring in a pool that maintains the depth you need and use your dock for a tender to access it.
Bilge keel boats are common over here, as you mention, but they are a compromise in sailing terms. Bouncing up and down on a had bottom can obviously be problematic, too. Much depends on the nature of the bottom. If it's soft mud, that's probably the best thing, though that can also cause problems. It's been known for one keel of a twin-keeler to become stuck in mud causing the boat to be flooded by the rising tide. Very rare, I'm sure.
Lifting keels or centreboards are also common here. Soft mud can clog up the centreboard case or keel slot with these, and stones can be a problem too. Stony or pebbly bottoms can abrade glass-fibre quite quickly. There's no perfect solution

[gonesail]

I had a monohull that dried out in the mud at low tide. the keel just burrowed down and the boat rested on the bottom. none of the thru hulls were affected or clogged up in the process. would I do this full time with my boat? no.

[AJ_n_Audrey]

I live not far from Sunset Beach, so I understand. The tides around here are in the three to 3.5 foot range usually. You don't want a sailboat resting on the bottom regularly in my opinion, so a better option is to find a house with a deep(er) water dock. Another thing to consider is which inlet you plan to go out through. A Catalina 36 draws 5.8 feet per Sailboatdata, so you may want to talk to some people using the Little River Inlet to find out how much local knowledge is required - I see conflicting reports. I use the Cape Fear inlet which is 40+ feet deep, so it is never an issue for me. As for the Cat versus monohull, that's personal preference, but a Catalina 36 would be my choice, and it's much cheaper.

[Exctyengr]

I can't speak to shoal draft, east coast sailing, but I can speak to Catalina 36's. They are an excellent boat, kind of a Chevy Impala of boats. They are comfortable, sail very well, reasonable initial build quality, roomy for their length and comparatively inexpensive to own. Moreover, they are popular so resale is good.

[SPC]

There's a 4.5ft shoal draft version of the Catalina 36 (MK1 anyway).

[Jahwork]

Greetings fellow mariners,

Here are a couple of pics of our Solaris Sunrise Sport 36’ catamaran at our dock. Due to it being on a river with lots of sediment we rest on bottom at tides of 1-2 feet or less. Been doing it for years, both with this boat and previous boats with no troubles other than coordinating arrivals and departures accordingly. Makes it easy to scrub the bottom and change zincs. This boat is designed to rest on it’s own bottom. It has “beach-able” keels with sacrificial keel shoes for just such occasions. Not right or good for all boats.......but for some it works out alright.

I threw in a pic of my neighbors monohull across the dock from me as well for reference.

Sorry I am a computer moron so you might have to turn your screen or head to match my pics.

Safe Journeys,
~Jake

[Jeannius]

Originally Posted by Davy J

Would I want my personal boat to endure that regime on a daily basis...... No.


Also, don't forget, planning your sailing around the ability to get in and out, based on the tide, will be a big PITA.........

Sadly that's the only option for many thousands of sailors over here in the UK. Huge number of places where we have up to 50 ft tidal range and the only financially viable way of owning a boat is accepting limitations on when you can sail and having the boat sit in the mud for long periods of time. The UK built a lot of boats just for this situation. Take a look at this article... http://www.tsl-online.co.uk/wp-conte...April-2013.pdf

[SPC]

Thank you all for your responses.

Here are some pictures of the dock at low tide. The channel doesn't actually drain all the way, though I'm not sure, would a 14ft beam go too far into the right-of-way (maybe 50ft wide)?

You can see from the stains in the dock next door, tides are about 4ft. More suitable pilings might be installable next to the dock for tie up, perhaps.

[hpeer]

Get a kayak or rent a boat for a day (in season) and take a long tour of the area. Look at what other people are doing. Bring a camera. May or may not help but will be an enjoyable day.

Our 44’er was built in the UK. 6-1/2’ draft. She is fitted for legs with 2 attachment points on each side. We don't have the legs or need them, just noting the boat was built with drying out as an option, and at 40,000 pounds she is not a small boat. On the other hand the keel is 27” WIDE and flat.

[valhalla360]

A gemini can certainly do it (pull the boards and rudder up once docked). We've set our Gemini on the bottom in really shallow slips but always under careful watch and in calm conditions.

If you are going to do it, I would want to be very sure it's soft mud and clear of hard obstacles. The bottom of the Gemini hull is not very thick, supported by soft mud, no concern but a stone or branch sticking up could punch thru the bottom relatively easily.

If I was doing it regularly, I might consider laminating a 4-6inch strake as a sacrificial support along the centerline of each hull. If it wears down, you just add a few more layers never touching the main hull.

It looks like it's pretty well protected, so wave action is unlikely to be an issue as the tide is going out...that would be my bigger concern. Even in relatively soft mud, bouncing regularly is not a great idea.


As mentioned, a bit of a hassle but still very much doable.

[Sand crab]

There’s a Gemini 105mc at a private residence here in the Puget Sound that rests on its bottom twice a day and has been doing it for years. That area probably gets up to a 15’ tidal range but no real current because it’s a protected cove.
The Aussies beach some of the cats regularly. There has been pics here on the forum.