Garboard Drain
  from the 
                Tayana List 

    One of the local marina operators in my area recommended installing a garboard drain in the low spot of the bilge. During winter layup the plug would be removed and any water leaking into the bilge would drain out.

    He especially advised doing this on boats with masts that are keel stepped because they tend to leak water into the bilge during the winter layup, that is, if the masts are not removed.

    I think it is a good idea and was wondering if anyone had any pro's or con's regarding this suggestion.

John Keefe	 CT37 	   Odyssea 	Youngstown, NY (Lake Ontario)     November 2005
________________________________________________________________________

John,
    A garboard drain plug is particularly desirable in a wooden boat; fresh water in its bilges would otherwise promote/accelerate rot.  (The term "garboard" refers to the planks on either side of a wooden boat's keel.) Very few FRP boats, however, have a (garboard) drain plug. Do you really want another hole in the bottom of your boat? If you do install a plug, make sure it complies with ABYC standard H-27: "If installed, drain plugs shall be installed in what is expected to be the lowest portion of the bilge when the boat is in storage. Drain plugs shall be accessible. The use of expandable type drain plugs shall be limited to boats equipped with floatation in compliance with ABYC H-8, Buoyancy in the Event of Swamping".

    For my money, you'd be better off spending the same time/effort keeping the water out of your boat in the first place, e.g., tape over mast exit boxes for the winter. The golden rule of boat maintenance is "Keep your bilges dry." A drain plug is a short-term solution to standing bilge water. One aspect of a drain plug that I do like is that they typically improve ventilation of the bilges during winter lay-up.

Sue Canfield 	T37 	Aeolus 	Annapolis, MD		         November 2005
________________________________________________________________________

Sue,
    Thanks very much for your comments.  l do like the idea of a garboard drain in the keel for two or three reasons.
 
    First, for the ventilation afforded the bilge during the winter lay-up and second, that it would drain any water in the bilge that may come down the keel stepped wood mast, if the mast is left up during the lay-up.
 
(The garboard drain is the same kind as used on a wood boat. It's a bronze flange with a 1" flush mounted bronze drain plug. It is glassed flush into the side of the keel at the lowest point of the bilge. Once installed the only part that you see is the top of the drain plug flush with the keel. )
 
    The third benefit is that it is easy to take a hose to clean and flush out the bilge when hauled. Very helpful in removing things which may cause odors and debris which could damage electric bilge pumps.  I've got some time to think about it, now, but the more I think of it.....I like it.
 
Regards, John Keefe						                     November 2005
________________________________________________________________________

    Interesting that you bring up the question of garboard drains today.  I just earlier today removed my bilge tank and was physically inside the bilge scrubbing the accumulated goo and contemplating a garboard drain.  I decided against it as the the root fillet at the bottom of the bilge is about a 3-inch radius and that would necessitate intalling a ferrule into the bilge at the very bottom and through the fillet so the all the water would drain as if one drilled through from the top of the fillet so that the drain hardware would align with flat surfaces on each side of the keel wall, there would be significant water left and unable to drain.  I'll just continue to load the bilge with a few gallons of antifreeze. 

    For what its worth, copper-nickel coins and stainless nuts that get into the bilge and come in contact with the underside of the aluminum tankage easily bores holes into aluminum better than a machinist with a drill press. Why anyone would intall an aluminum tank in a bilge that can get seawater into it is 'wonderous'.   I also now understand what those who have removed this tank are talking about when they say 'construction debris'. Definitely there will be a screen 'coffer dam' on both ends when the rebuilt tank gets installed. 

Rich Hampel								         November 2005
________________________________________________________________________

    I'm going to take a closer look at that turn in the bilge, Rich, as I have my tank out, too. It's not a priority but I really like the idea of a garboard drain and I'm prepared to make modifications, if necessary, to get it right. But that will come later as I have enough things to do now. Also, I found a load of debris and junk in the bilge when I removed my tank.

    What type and gauge of stainless steel will you use for your new tank? Is it for water or fuel? What capacity do you have in mind if different from the OEM tank? I guessing you have a 100-gallon tank now.

    When you completely dry out your bilge, double check the bottom of the bilge floor just in front of the holding tank bulkhead and going forward a foot or so for any dampness migrating up from it. Lay some chalk dust or similar on the area for a day or two and if it indicates moisture is present, your holding tank may be leaking into the enclosed ballast cavity. It probably isn't but while your spending time wandering about down in there it's easy to check.

John Keefe								         November 2005
________________________________________________________________________