Originally Posted by TallRedRider
I didn't even know this valve was there until I took the ballast system apart and put it together decently. You have to dig for it, so it might actually be easier to put a fake a lake on the bottom ballast intake, but my 06 X45 had this on the starboard drain hose. I am sure it was intended to be used for winterization of the ballast system.
My 06 has that as well.