cd-25 cockpit drains

B

bcarli

New member
Hi all

looking at the cockpit drains on our cd-25 it seems like there is not much elevation between the cockpit floor and the drain output on the hull. We leave our boat in the water year round where snow is un-common but not unheard of. I wonder if enough wet snow filled the cockpit could it put the stern down in the water enough to flood the boat?. I have shoveled 2 feet of snow off the docks in the past. Any thoughts?
I'm sure there are
thanks
bill
 
I have a 25 and the drains look small to drain out any water.
I live in montana and have moved a lot of snow it can be heavy.
it could put you down by the stern but i think it would take a lot of snow
to cause you a sinking feeling
:smiled john schuler :smiled
 
Things that make you go "Hmmmmmm"

Went to a Canadien website about snow loading on a roof and, instead of learning the math, stole from the example where 3.5 feet of snow gives a load of 40lbs per square foot.
With this example, two feet of snow would load the back end of a 25' Cruiser at 906 lbs ( which would equal a full tank of gas and one or two people sitting in the back).
I think its a great question and not likely to have any impact on dipping the back end.
I know the 22' Cruiser often has a triangle shaped canvas mooring cover that just covers the cockpit and might be worth investigating. Haven't seen one on a 25' Cruiser.
Please keep us posted as to your experiences!
Fair Winds...
John
 
Bill and Chris-

" I wonder if enough wet snow filled the cockpit could it put the stern down in the water enough to flood the boat?."

Certainly if the snow were deep and / or wet enough to cause the scuppers to take on water (we've heard before that they will let some water in if the stern sets low enough), the water would begin to invade the floor.

The floor is slightly above the waterline, and all the compartments are presumably sealed, although we've also heard of some 25's that had leaking compartments and some just plain without good seals.

So how much water and snow would it take to get enough weight in the cockpit to allow water to enter under the cabin door and begin to flood the entire boat?

And then what would all this water do? Simply float the boat awash, or would it flip over since the bouyancy is in the cockpit floor and under the v-berth?

This is much the same question we've had asked before about the various C-Dory models, and also tried to answer using observations of those very few that have actually been totally flooded and capsized.

There's not a lot of annectodal evidence to examine here, but most signs point toward conclusions that at some point, the boats will roll over, bow up.

Perhaps the 25 's, with their rear cockpit floor bouyancy, would float with the entire hull level awash and inverted. That's my best guess, anyway.

So you then have to go back and ask yourself just how much water intrusion through the scuppers would it take to destabilize the upright but flooded boat to cause it to roll over.

My best guess here would be that there would be an input into this instability from the sea and wind conditions. In a rough sea and wind, the boat would roll over due to the added pitching instability earlier than if it were in flat calm conditions.

How likely is the snow to do this? Apparently it hasn't happened yet, probably because no one moors a boat out in the open in blizzard conditions. Chalk one up for sensibility for most owners! Will we ever see this happen? Could happen in a surprise storm, I guess.

Another factor to think about is that the water surrounding the boat is above freezeing temperature and will try, perhaps slowly, to melt the snow in the cockpit, but the snow rate could easily exceed the melt rate.

Who's up to be the test guinea pig? One of the boys up in Alaska could back up a 25 to a fish processing plant and begin filling it with finely shaved ice and see how it goes! Any takers? I didn't think so!!! Joe.
 
Bill,

I doubt you will see enough snow in Washington to cause a problem but it is possible. If we were to get 2-3ft of snow I would go shovel it out! If you are really worried about it have a slanted cover for the cockpit made (if I were mooring my boat I would have one made!) so that the slanted cover is unlikely to hold any snow/rain water.

While the analysis above about the 900lbs seems correct the question becomes is the 900lbs enough to get the scuppers lower than the water line. If it is then you would have a potential threat. So, if you want to find out get 3 or 4 people my size in the back of the boat and you will quickly find out!
 
New Guy-

Not to be a wise guy, but I get slightly different figures for the weight loading.

The CD-25 is 8'6" wide at the beam, and the cockpit approximately 7' long from scaling the pictures of the boat. The factory still doesn't have a line drawing available on the web site.

Since the beam is narrower at the water line, we can use a beam of 8' and a cockpit length of 7' for rough estimating. This gives an area of 56 square feet.

Using the 40 lbs per square foot figure for 3.5 ft of snow, we get

56 x 40 = 2240 lbs for the cockpit, plus the weight of the snow in the motor well and roof.

If we go and figure the whole boat with an average width of 6' over the 25' length, we get 6' x 25' x 40 lbs/sq ft = 6000 lbs ! (Theoretically, of course.)

Get the shovel out, mate, and get that white stuff overboard. I'll stay here and tend the coffee pot and make sure the Wallas doesn't have a flame-out!

.... Joe.
 
Wow Joe,

You are going to make us break out the calculator and algebra! Lets see if I have this right. If 3.5 feet of snow weighs 40 lbs/sq foot then 1 ft of snow would weigh about 11.4 lbs/ sq foot. That means that our equation would look like this...

At 1 foot deep...
11.4 x 25 ft x 6 ft (avg beam) = 1710 lbs. OUCH. Might want to get out the shovel!

At 2 ft deep 3420 lbs. Better hurry! Now we know why snow loads are so critical!
 
Weight of snow depends on moisture content. We live in snow country but three feet in one day is rare. It happened here on October 30th 1990. Our average is 120 inches a year. Jack on C-Otter.
 
It is reasonable to worry about this even in Seattle. While it doesn't happen that often it occasionally can snow A LOT. About 10 years ago (I don't remember the exact year) we had a day in which it snowed about 1 foot, followed by a clear day, followed by another foot of snow which subsequently transitioned into rain. That resulted in 2 feet of water saturated snow in places - very heavy.

A number of marinas lost boats when floating, covered docks (with mostly flat roofs) sunk under the weight of the snow. There were also numerous roof collapses in the area and a number of house boats listing on Lake Union. I had a nearly flat cover over my patio and a shallow roof and got out on both days to shovel the snow off. In addition, to the weight of the snow, many of the drains/gutters for roofs were clogged by the snow resulting in more water weight. Hence, the question is, in my mind, a very valid concern.

Roger on the SeaDNA
 
I don't know about snow load capabilities, but this past summer we had six people on our 25 for a BBQ (4 on the deck and 2 in the cabin). I too was curious about the scuppers and how much weight the back deck might hold before scuppers would start to submerge. We placed all six people on the rear deck (900+ pounds plus 490 pounds of fuel in the tank) and the scuppers remained above water.

Personally, I'm no longer concerned about the scupper question. :D
 
In defense of my math!

To Sea Wolf/ Wise Guy.
LET THE GAMES BEGIN!
There are line drawings available on the website if you look at the brochure. I used 4.6 feet long (cockpit with scuppers) and 8.5 feet wide (overkill) to keep the engineers from breaking me, but ALAS, to no avail.
I'm sure snow comes in different densities or the eskimos wouldn't have 176 different words for it. I used an average that Canadien roof architects use. Good enough for me. Also, I was using 2 feet of snow as that was the question and stand by the 900lbs (because it would typically be less).
I have a 25' C-Dory sitting about 20 yards from where I'm typing and was trying to convey that empty of gas and then... loaded with gas and a person or two in the back does not noticabley dip the aft end. I'm sure in the perfect storm, anchored by the stern, crossing the international dateline we could figure out a way to screw up a 25' Cruiser. It was my ever-so-humble opinion that 2 feet of snow (the original question) would not qualify.
Of course, we could counterbalance by adding snow on the bow, and people sleeping up front, and the upcoming effects of daylight savings time...
Just trying to add some data and levity.
Love being a BRAT!
(And with all this input now strongly recommend the mooring cover!)
You guys are great! Winter is coming so I'm sure we can solve this. I Vote CANVAS!
Fair winds...
 
The snow load for one foot of snow cannot be definitively defined, as all snow has a different density and weight because of water content. I was a liveaboard in seattle, I believe the year that comes to memory was 1994, somewhere around there. Two feet of snow built up over my sailboat, completely over my sailboat including the decks and dodger. Then it thawed for an afternoon, placing the melted snow into the the next layer of snow as water, turning to ice in the evening. Then the next night it snowed another foot. There is no shoveling that stuff out. I used a screwdriver to pick my way out of the companionway. A lot of boats went down in the marina, not necessarily because of the weight of the snow, but because the scuppers plugged up and the water continued to build up within the snow. Eventually you use up all the reserve bouyancy of the hull and it either rolls, or goes down stern first. The same thing happens in portland a little more frequently. The columbia river has some severe ice storms every three or four years. I always overnighted on my boat when those occurred. Best offense is to get enough heat throughout the boat to keep snow and ice from accumulating. But when the power goes out, game over.
 
wow
what answers!!!
I like the idea of some sort of sloped cover for the cockpit. I know that the hatches on the cockpit floor would not keep any water out so that area would flood. I should just buy a used cheap trailer and haul the boat out if we leave for a long time in the winter. Any used trailers out there in the Seattle area?
thanks for the input
 
New Guy- Excellent defense! I used the figures you gave for density and snow depth along with a guess as to cockpit length just from a photo. Didn't think to see if there was one on the brochure. Wonder why they haven't posted that drawing under the "Line Drawings and Dimensions" heading under the CD-25 information section of the site (?)

Of course I choose the maximum estimated dimensions and other figures to exaggerate the differences once I choose to question your figures, so as to not to appear to just be nitpicking as well as make the point that serious consequences can result-- just standard debating technique, making a the point into a Moose, not a Mouse. Had you shown how and why you adjusted the raw figures down to be more reasonable, I would have probably let it go! (Yep, I know most people don't like any math they can avoid!)

But we definitely do hear that the snow and ice accumulation can be a real problem with catastrophic results as evidenced by the posts of Lloyds and Rogerbum. And, as I recall, Steve J had his Sherwater (one of the original CD-25 Cruise Ships) dumped on when a marina roof collapsed a couple of years ago, forcing a serious amount of transom repair as well as a kicker replacement.

All the fun and games and spirited debate aside, snow and ice can pose a real danger to our boats, even the ones on the trailer, if they're not prepared right for freezing weather and properly shielded from dangerous levels of snow and ice accumulation.

Even the Coast Guard Cutters and Icebreakers can be capsized by the weight of ice accumulation at deck level from sea water spray if the sledgehammer boys on deck don't get their job done!

Some who are interested may want to start a discussion on the different methods of storing a boat outside under adverse conditions when or where covered storage or storage inside a building is not available, a topical discussion for this time of year!

Fun talking with all of you on this thread! Stay warm and put the C-Dory to bed dry! Joe.
 
Joe //Sea Wolf
You are wiser, so I rely on a sense of humor (and eventually humility) to get me through. The point was well made that there are winter extremes out there and the BRATS are lucky to have this deep pool of experience.
To show the 'Great Minds think...' etc is alive and well, I actually started a "Winterizing Ideas" thread a week or so ago that was great for a couple of days, but then fell off the curent list. Now the subject is in the Polling area I believe...
We are already using two of the ideas at our Marina for this winter's storage plan. So from Y-Landing, THANKS!
Everybody keep up the good work!
Fair Winds...
John
 
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