Hairline cracks and water

I have a FireWire addvance and noticed that a section of the bamboo deck is turning darker. After close investigation I found a 3" hairline crack in the rail beside the discoloration. I'm guessing water has got in here and has dampened the bamboo deck. My question is how do I get it out?
Should I put a larger hole in the rail to allow it to drain out?
Cheers
Paul
Should I put a larger hole in the rail to allow it to drain out?
Cheers
Paul