Originally Posted by mikehoyt
Many boats at our marina have garbord drains.
Our boats are hauled during the winter and the marina is not patrolled regularly. Typically snow can fill the cockpit and than rain/freezing rain can put a hard layer over this snow and also cover cockpit drains. A mid winter rain storm will then fill cockpit to level of hatchboard and flow into boat.
This does not happen often but there are many ways in which water can find its way into an unattended boat over winter and easily rise to or over floorboard level. One boat in our marina had replaced the cabin sole only to have this happen over the following winter. After that a lot of boats installed garbord drains.
Another option is to remove the speed transducer to leave this as a drain. It is much higher than the bilge though and the possibility of water filling the bilge and freezing would still exist - though below the floorboard level.
Garbord drains are not at all difficult to install and unless you have a cored hull I do not see this as a major problem. I do however see water sitting in a boat on the hard as a major problem.
I installed one and am glad to have it here in Maine.
It isn't obvious in this picture but I added 1/2" of biaxial S-glass with vinylester resin to the inside of the keel stub to prepare for the plug's installation.