How much draft is too much?

[bowball]

Of course, the answer is when it is greater than the water depth!

Setting that aside, I’ve been watching video of a Delta built 70’ yacht named Oasis, which is very impressive (as is the owner).

Oasis apparently has a 10’ draft; my trawler is 5’.
What do you give up in real world exploration in the PNW by having such a deeper draft?

I assume the advantages are stability and that awesome stand up engine room.

Any thoughts on this?

When does it make sense to go to a deeper draft? Which missions or geography? Alaska to Mexico. Maybe to Caribbean.

 

[O C Diver]

While I don't know the west coast, when you wrote Caribbean, that could have a dramatic impact on where you can anchor out and some passages between islands. If the goal is to go from port to port, it's probably less of an issue. It would certainly make navigation more challenging in the Bahamas and Florida keys if you want to get off the beaten cruise ship path.

There's a joke about everyone running a ground, and some (deep draft boats) just doing it further offshore.

Ted

 

[rgano]

Certainly a useless draft in ditch travel on the east coast.

 

[bowball]

Certainly a useless draft in ditch travel on the east coast.

I really was thinking predominantly and maybe exclusively west coast.

 

[rgano]

I really was thinking predominantly and maybe exclusively west coast.

Yes, I unnerstan, and that's a good thang.

 

[Lepke]

I've run ships, tugs and fishing boats on the West Coast and never found deeper drafts prohibitive. Obviously there would be some places you couldn't go. But there are plenty of anchorages, bays, harbors, rivers that would be safe with a 10' draft. I think I've crossed every bar on the West Coast and they all would allow a 10' draft at the right tide.

 

[BandB]

All depends on where. On the west coast, draft is seldom an issue. I've known those to cruise the entire west coast including Alaska with 7'6" drafts on Westport 164's. We cruised much of the West Coast with a 6'6" draft.

Plenty of boats in the Caribbean with 7 to 9' drafts. Just look at all the charters of megayachts.

Obviously you can't do the ICW comfortably with shallow drafts. With greater than 5' it becomes a challenge to plan by tide and greater than 6' a major nuisance. Can be done, just most boats with that kind of draft will run outside instead. Many boats cruise the East Coast with 6' to 8' drafts. Look at the yachts in Fort Lauderdale or Newport.

In the Bahamas, you'll see large yachts with 7 to 9' drafts, but they can only dock and anchor in perhaps 10% of the areas most of us would. They then use their tenders to explore the rest.

In other areas you'll see large boats that just cannot get into the desire marinas and will anchor out and tender in and out.

It's funny that Europeans and European boat builders don't seem to grasp the American obsession with draft. For that reason, we find many of their boats not to be suitable for East Coast and Bahama cruising. A typical 65' Italian sport boat will have a draft of 6'.

I will give you some insight into our purchasing thoughts. On any boat under 100' to be used for coastal or for loop or Bahamas cruising, we prefer to stay around 5'. If we were on the west coast, we'd likely extend that to 6' but still there are just those places 5' is nice. For instance, head down to Astoria and you're fine with more, but if you want to then explore 100 or more miles of the Columbia river I think you'd be happiest to have less. Easy to cruise from Port Angeles to San Francisco with 9' draft, but if you want to stop at many of the marinas along the way, draft can be an issue. We did so with 6'6" and I would have hated to have had more. Get to San Francisco and you're fine but if you want to explore the Delta, then draft becomes an issue.

If you're over 100' then a 7' draft won't become an issue because any marina that can accommodate a boat that size can handle the draft. It all fits together. Still, we find 7' even in the east and the Caribbean gives a lot more flexibility than say 9' or more. However, the owners of 9' drafts have adjusted.

It was a bit humorous cruising this summer in Europe as marinas would ask our draft while stating their depth. We'd inform them with a 4' draft, it wasn't a problem for us.

I'd encourage people to look at their specific favorite cruising grounds. You'll often hear things about both draft and size that really overstate the issues. We were told you'd have major problems finding dockage on the loop with anything over 40-50' but with 69'4" and a draft of 5', we never had an issue. Now we were told on the East Coast of Canada and between there and Quebec, over 60' would be very limiting. It was. We had to plan ahead carefully. The government marinas were limited. If you're going to Atlantis in Nassau, Bahamas, draft won't limit you. Size and draft aren't an issue, just the $7 per foot. But if you want to fully enjoy the Exumas, over 5-6' will be extremely limiting.

 

[long-cours.62]

For us less than 1.30m is good...
When I try to design the next one my goal is 1/1.1 m

 

[BandB]

For us less than 1.30m is good...
When I try to design the next one my goal is 1/1.1 m

And where do you encounter draft problems? The Rivers and Canals? I'm guessing there and not the coast.

 

[cafesport]

I think it mostly depends on where you intend to cruise. 40 years ago when I got tired of the Bahamas I bought a boat that drew over 9’ when tanks were pressed for offshore passages, Draft was never a problem in most of the world until we returned to Florida. Ended up having to move her to bermuda to sell her though so I tend to think of draft as a local condition. 8’6” in anacotes is different than Miami.

 

[markpierce]

I've run aground twice with a two-foot-draft sailboat and four times with a four-foot-draft sailboat. Dragged the keel twice through mud with my current four-foot-draft motor boat. All in the last sixty years. Lots of shallows in the San Francisco estuarial waters. Choose the boat whose draft works with your waters, and may you only ground on a rising tide like me.

 

[Alaskaflyer]

Call me conservative in my passing and anchoring but there’s no place I’ve boated in SE Alaska or Puget Sound that I couldn’t have easily taken a boat with 10 foot draft, with the exception of the government boat dock behind Bartlett Cove

 

[bowball]

I’ve fallen in love with the yacht Oasis, a Delta 72 that the owner has posted quite a few videos about seamanship - one look at the lines of it and the engine room. 10’ draft.

 

[long-cours.62]

And where do you encounter draft problems? The Rivers and Canals? I'm guessing there and not the coast.

You have lot of place you can't reach with deeper draft, some anchorage in Sardinia, Croatia, Poland, the best and more secure anchorage in Corsica you can't get in with more than 1.60m ( at 1.6 you touch), very nice and protected anchorage in Sweden, Finland, Brittany, Vietnam even with 1.30m in some place we drag the mud... etc etc

If you have a boat for only stay at sea or in Harbor of course you could have 10' draft (and not in all harbor...)

 

[Insequent]

In Queensland and the islands in and around the Great Barrier Reef (but not the Reef itself), the old saying was "another foot on your draft means another mile further out from shore to anchor". A bit exaggerated, and boats with 7' draft can manage, but best to be not much more than 5' and preferably less.

Where you use the boat is key. There will be exceptions, but around the world tropical waters & low latitudes areas favour or often require shallow draft boats. Generally, higher latitudes draft doesn't matter. In looking at boats at Anacortes years ago, and always asking about draft (given my tropical home cruising grounds) the broker laughed and said "in these parts either you're in 600' of water or on the rocks". Not exactly true either, but the biggest challenge I found in the PNW was finding water shallow enough to anchor in.

 

[BandB]

You have lot of place you can't reach with deeper draft, some anchorage in Sardinia, Croatia, Poland, the best and more secure anchorage in Corsica you can't get in with more than 1.60m ( at 1.6 you touch), very nice and protected anchorage in Sweden, Finland, Brittany, Vietnam even with 1.30m in some place we drag the mud... etc etc

If you have a boat for only stay at sea or in Harbor of course you could have 10' draft (and not in all harbor...)

Thank you for clarifying. We primarily use marinas and in Sardinia, Croatia, Corsica, Sweden, and Finland didn't encounter any areas or any marinas where draft was really an issue. We have not cruised to the other areas you mentioned. Similarly, we haven't looked for protected anchorages.

What it indicates is that not only is location a factor, but type of boating is as well.

 

[Mako]

Like has been said, it's all about where you want to cruise.

When I was in Oman, right off the Straight of Hormuz, you could throw a rock off the beach and be in 600ft of water (slight exaggeration, but not much). We anchored right on the beach though, with 100ft of rode.

That Delta 70 is an amazing vessel, pioneered by Bruce Kessler. But no one is going to build a vessel like that and then spend their days cruising the ICW, Ft Lauderdale and the Bahamas.

You're going to take it all around the world. From Alaska down to the Channel Islands through the Panama Canal and all over the Caribbean, you won't have a problem. Or perhaps stay on the left side of America and circumnav the Pacific Ocean.

OP, I hope you have the budget for a vessel like that, but bear in mind that after Kessler's Zopilote sunk he opted for a similar vessel but downsized to 57ft (if I remember right).

 

[long-cours.62]

Some interesting anchorages

Thank you for clarifying. We primarily use marinas and in Sardinia, Croatia, Corsica, Sweden, and Finland didn't encounter any areas or any marinas where draft was really an issue. We have not cruised to the other areas you mentioned. Similarly, we haven't looked for protected anchorages.

What it indicates is that not only is location a factor, but type of boating is as well.

We mainly use anchorage and for the few example attached if our boat had more draft we can get inside. They all are very good anchorage well protected, for example when we was on witch one named "Suède 2" we got little wind inside but outside it was a big storm with oil platform and ship damaged ... With deeper d hull we must stay in less protected place or go in harbor but harbor we don't like...

 

[Hippocampus]

Think B&B said something important. Do you anchor or marina cruise. Our cruising has been US east coast and Caribbean. Frequently the bays have a rim of shallow water with very deep water in the middle. The sea life tends to be in the shallows where there’s coral or grass or at least enough light penetration to support some form of flora hence fauna. So the diving, snorkeling and even fishing can commonly be done without getting in a dinghy. Also even in a blow you can get 5:1 or better with 200’ or less. Anchoring is fast and easy. Repositioning ain’t a biggie. Trips in are short and given done in the shallows the big waves break before the waters you travel.
Just spent a decade cruising an Outbound with a 6’6” draft. Looking forward to losing a foot and a half with the NT. Have had high aspect fins with even deeper draft. Sure it doesn’t matter when the depth is ——- on the screen . It a different life the less you draft if you mostly anchor. So beyond the region(s) you cruise the style of cruising has a big impact on what you will tolerate.

 

[O C Diver]

Part of the consideration regarding draft is what the bottom is made of. I've spent a lot of time in the skinny waters of Chesapeake Bay, GICW, AICW, and many other areas where the bottom is mud or soft sand. Don't mind bumping the bottom with the bronze skeg when venturing off the beaten path. It's a very different situation in places like Lake Superior where the shallows can be covered in bolders.

Ted

 

[Hippocampus]

To expand on Ted’s excellent point. The boats bottom and appendages not just the bottom is relevant. I’m on a single screw, full keel, no fins or fish. Compare that to a twin with exposed running gear. Worst case for me is I suck up mud and/or lose some bottom paint.
For awhile winged keels were a fad. Sure increased lift and decreased draft but when you ran aground they were an anchor. Couldn’t throw an anchor to the side or move weight to tilt. Couldn’t spin off like a finned keel Couldn’t back down to get off. Compare that to an English boat with twin keels built to dry out without troubles. Decreased draft with no damage.
Many things come into play (dry v wet exhaust, where cooling water intake is on wet exhaust, nature of appendages, construction of fins, is the boat built to take a hit when running aground etc.). So a simple number for “draft” doesn’t tell the total story. Seen multis with sail drives get into big troubles. Have daggerboards so draft next to nothing but running aground can be quite a mess.
Lastly how far you are from the equator matters. Is the tide measured in feet or inches. Run aground in New England you’re stuck for a few hours. Run aground in Grenada or Trinidad you may need to be floated off.

 

[mvweebles]

A friends boat and mine have the same draft on paper - 4'6". My Willard 36 has a traditional long-keel with fully protected prop. His boat is a 52-foot Power Cat which while having exposed props, also has decent sized skeg-keels that drop at least 6-inches below the prop depth. In the yard, the props look protected. Yet he somehow managed to tap bottom doing 18-kts which wasn't cheap to repair. Guessing maybe his skeg sliced through the sandy bottom and his prop found something meaty.

Consequently, he gets nervous as la ong-tailed cat in a room full of rocking chairs if he registers anything under about 7-feet. Me? To Teds point, I don't care too much in sand/mud bottoms. Many years ago we were up the SF Delta and took a small tributary slough. When it rejoined the main channel 12-miles later, there was a distinct silt-berm of about 3-feet deep x 10-12 feet long that had accumulated. Rather than spend 3-4 hours retracing our path and coming back up the river, we decided to go 'ramming-speed' and plow through the mud. We created quite a milk shake behind us but no problem.

My point being there is draft-on-paper, and then there is effective draft that adjusts based on bottom and boat. When I first moved to Florida, I thought it would be lousy trawlering - fast was good. Turns out its great trawlering. Many no-wake zones undermine benefit of speed. Keep a low boat for bridges, skinny water argues for well protected prop(s). Good sun protection.

Peter

 

[long-cours.62]

you are right

To expand on Ted’s excellent point. The boats bottom and appendages not just the bottom is relevant. I’m on a single screw, full keel, no fins or fish. Compare that to a twin with exposed .

For example the bottom of our former boat was 16mm tick + 2 "flat bar" 100x16 welded ... and this boat could "stand up" alone

 

[O C Diver]

If you plan to travel in skinny water, here are a few hopefully helpful tips:

1. If you have exposed twins and there isn't a keel that sticks down atleast a foot between them, don’t.

2. If you have a single without a skeg, see above.

3. If you have a single with a skeg, measure from the bottom of the skeg to the lowest point in the propeller rotation. Mine is about a foot. To me, the importance of this information is how much room you have between bumping the bottom and when you're risking the propeller to stuff in the bottom.

4. It's also a good idea to understand how deep the raw water intake(s) for the engine(s) are. Mine is around 2' on a 4.5' draft boat. While bumping the bottom with my skeg may be ok for me, sucking mud and fine abrasive sand through the raw water pump is not acceptable. Generally the raw water intake is far enough forward to limit bottom material from being picked up. If you get stuck and have to power backwards, assume a cloud of bottom debris is being pushed by the prop wash to your raw water intake.

5. Go slow in skinny water, idle speed in gear! No faster than you want to hit something. When crossing a bar or shoal water to get into an idyllic anchorage, I try to do it while the tide is rising. Know the tidal range before you head into skinny water. Getting stuck and having the tide go out will very likely lay your boat over on its beam. No one wants their boat to end up like the "Golden Ray"!



6. Again, Go Slow! As you go above idle in gear, the hull passing over the bottom creates a venturi effect that sucks the hull down (increasing the likelihood of a more significant striking of the bottom in the very stern). The speed at which this occurs varies from boat to boat. If you think about it, the venturi has to overcome the buoyancy of the stern of the vessel. Going slow enough prevents the venturi from being strong enough to overcome the buoyancy.

There is a joke about traveling the AICW. There are only 2 types of captains who have traveled the AICW:

1. Those who have touched bottom.
2. Those who lie about it.

Ted

 

[Circumnavigator]

Sweetwater, the Swan 57 on which we circumnavigated, is a centerboard sloop and draws seven feet with the board up. There was no place on the trip where seven feet was a significant problem -- only a few where we had to be careful. More would have been difficult. This was Panama, many Pacific Islands, the Cook Strait, inside the GBR from Gladstone to the Torres Strait, the Straits of Malacca, Suez, a variety of ports in the Med, and home.



Fintry draws between seven and eight feet depending on fuel load -- 40,000 pounds of fuel takes her down about six inches. In 20,000 miles of cruising, the only place we had trouble was a marina in the St. Clair River which was sure there was enough water for us. There wasn't -- see https://issuu.com/cruisingclub/docs/voyages_2020 starting at page 94(98) -- the marina is on page 97(101).


To be sure, on both boats there were places we didn't try going, but draft was never a significant inconvenience. Also, the Great Lakes were two to three feet above datum -- draft would have been more of an issue if they were much lower.


Jim

 

[rslifkin]

To expand on Ted’s excellent point. The boats bottom and appendages not just the bottom is relevant. I’m on a single screw, full keel, no fins or fish. Compare that to a twin with exposed running gear. Worst case for me is I suck up mud and/or lose some bottom paint.

That's a big one. We draw a little under 4 feet (last measurement said 3'9") loaded in fresh water. But realistically, with the props hanging about 5 inches below the keel, I won't go anywhere someone wouldn't go in a sailboat drawing 5 feet. But at least around here, that's not very limiting. There are a few places we can't go, but neither can anything else drawing more than 2.5 - 3 feet. Significant restrictions on access to anchorages, small harbors, etc. don't start in this area (Lake Ontario) until you're drawing closer to 6 feet. But there are some who cruise here with 7+ foot drafts and do fine, just a few places are off limits.


How well you know the bottom and clarity of water definitely matters too. There are a few places I'm willing to sneak in with the depth showing 5 feet or even just under, but that's only because I know darn well there's nothing sticking up on the bottom and the water is fairly clear. Other places, I wouldn't get that close. Generally in unknown water, I'm at idle by the time we're down to 6 feet, and depending on what I know about it, somewhere between 5 and 6 feet I'm in reverse.

 

[BandB]

Sweetwater, the Swan 57 on which we circumnavigated, is a centerboard sloop and draws seven feet with the board up. There was no place on the trip where seven feet was a significant problem -- only a few where we had to be careful. More would have been difficult. This was Panama, many Pacific Islands, the Cook Strait, inside the GBR from Gladstone to the Torres Strait, the Straits of Malacca, Suez, a variety of ports in the Med, and home.



Fintry draws between seven and eight feet depending on fuel load -- 40,000 pounds of fuel takes her down about six inches. In 20,000 miles of cruising, the only place we had trouble was a marina in the St. Clair River which was sure there was enough water for us. There wasn't -- see https://issuu.com/cruisingclub/docs/voyages_2020 starting at page 94(98) -- the marina is on page 97(101).


To be sure, on both boats there were places we didn't try going, but draft was never a significant inconvenience. Also, the Great Lakes were two to three feet above datum -- draft would have been more of an issue if they were much lower.


Jim

People sometimes ask about the use of sonar. Marinas is one place we find it handy. We've had marinas try to push us to a specific location that on sonar we could quickly tell was a problem. They argued, we turned around to leave entirely, suddenly they let us dock where we wanted. They continued to argue and after docking we made them walk with a pole over where they tried to put us and then proved to them that less than three feet from the dock it was only 3' deep. It had apparently filled in greatly from last time they knew. They then apologized profusely.

 

[BandB]

Sweetwater, the Swan 57 on which we circumnavigated, is a centerboard sloop and draws seven feet with the board up. There was no place on the trip where seven feet was a significant problem -- only a few where we had to be careful. More would have been difficult. This was Panama, many Pacific Islands, the Cook Strait, inside the GBR from Gladstone to the Torres Strait, the Straits of Malacca, Suez, a variety of ports in the Med, and home.



Fintry draws between seven and eight feet depending on fuel load -- 40,000 pounds of fuel takes her down about six inches. In 20,000 miles of cruising, the only place we had trouble was a marina in the St. Clair River which was sure there was enough water for us. There wasn't -- see https://issuu.com/cruisingclub/docs/voyages_2020 starting at page 94(98) -- the marina is on page 97(101).


To be sure, on both boats there were places we didn't try going, but draft was never a significant inconvenience. Also, the Great Lakes were two to three feet above datum -- draft would have been more of an issue if they were much lower.


Jim

Wifey B: I'm still amazed at all the desire to go in shallow water and where it's very close and bump along the bottom and such. There are oceans full of water. There are many waterways deep enough and channels,, especially at decent tides. It's like people parking cars who squeeze into a narrow space rather than walk a few extra steps. Even in a jet RIB, I always try to have at least 2' more depth than I need. I just don't care to cut it close. Like you, we've found plenty of water all around with few places we wanted to go and couldn't get to.

 

[O C Diver]

Wifey B: I'm still amazed at all the desire to go in shallow water and where it's very close and bump along the bottom and such. There are oceans full of water. There are many waterways deep enough and channels,, especially at decent tides. It's like people parking cars who squeeze into a narrow space rather than walk a few extra steps. Even in a jet RIB, I always try to have at least 2' more depth than I need. I just don't care to cut it close. Like you, we've found plenty of water all around with few places we wanted to go and couldn't get to.

I would guess that a lot of it has to do with idyllic locations (anchorages) to enjoy mother nature.

Frankly I can't understand why some boats choose to dock in tight marinas, ofter within 10' of another boat. Some marinas remind me of a satellite view of a flooded mobile home park.

I wonder if your risk of boat damage (from other boaters and debris on the bottom of slips) is greater in transient marinas or traveling in skinny water?

To each their own.

Ted

 

[BandB]

I would guess that a lot of it has to do with idyllic locations (anchorages) to enjoy mother nature.

Frankly I can't understand why some boats choose to dock in tight marinas, ofter within 10' of another boat. Some marinas remind me of a satellite view of a flooded mobile home park.

I wonder if your risk of boat damage (from other boaters and debris on the bottom of slips) is greater in transient marinas or traveling in skinny water?

To each their own.

Ted

Wifey B: I like marinas so I can go explore sites around town.

As to anchorages, I understand easing in as you describe and we occasionally have done so. What I don't get is cruising in shallows and ICW at low tide when very close rather than waiting a bit or taking a wider turn. The way you do it, easing to the anchorage, I get. However, those who bump along their way while cruising, I don't. I know one guy who bought a boat with pods and knocked one off. He said "I never had a problem here before." Well, previously he bumped his way along.

I don't understand cruisers who cut it close. That's way different than easing to an anchorage.

Example: NJ ICW. Why try it? If you must only at high tide please.

As to damage at marinas, good point, but we've avoided so far. However, it's required diligence and stubbornness. Dockmasters trying to squeeze another boat where there wasn't space. No different than boats trying to squeeze into full anchorages. Oh, and boats rafting but lacking adequate fenders.