USCG depth vs draft. What's the difference?

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Pmcsurf1

Senior Member
Joined
Feb 1, 2020
Messages
298
Location
USA
Vessel Name
Agape
Vessel Make
Californian 45
We just registered our boat for the first time and are in process of transferring USCG documentation. CG certificate shows length 36.6 feet. Okay that's waterline not overall. My question is they have the "depth" as 6.1.

I spoke to CG on phone. They told me they get that number from the manufacturer. My understanding is the draft is 3'8".

Does CG define depth as something different from draft?
 
Depth is the height from the lowest point of the hull to the hull-deck joint. Basically the interior depth of the hull itself. Draft is waterline to lowest point on the boat (including anything that sticks down below the hull).
 
Depth is the height from the lowest point of the hull to the hull-deck joint. Basically the interior depth of the hull itself. Draft is waterline to lowest point on the boat (including anything that sticks down below the hull).
Did not know that. Thanks.
 
Realize also that the tons on a USCG document are interior volume , nothing to do with weight
 
Depth is the height from the lowest point of the hull to the hull-deck joint. Basically the interior depth of the hull itself. Draft is waterline to lowest point on the boat (including anything that sticks down below the hull).

Huh. You learn something new everyday. Dammit, it’s my day off; I didn’t want to learn anything new today!!! ?
 
Comes from the days of steam, when it was important to know the carrying capacity of coal. Hence depth is related to coal capacity, length is measured from the fore part of the rudder stock to the stem, so only coincidentally related to WL length on some boats, nowhere close on most. At least that is how it is here in Canada and since the US and Canadian rules were created back in the mists (clouds of coal smoke) of time, they have similar origins.
 
Depth is the height from the lowest point of the hull to the hull-deck joint. Basically the interior depth of the hull itself. Draft is waterline to lowest point on the boat (including anything that sticks down below the hull).
:Thanx:
 
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