On Fri, 10 Nov 2006 17:36:36 GMT, "scbafreak via BoatKB.com"
u25927@uwe wrote:

Well this isn't exactly an old boat. It was completed in 1994. It has a
water maker onboard so I don;t think they will plan on taking a barrel up a
river to get fresh water. I found the rest of the add that the picture comes
from here.

The barrel might have preceded the water maker or maybe just served as
a backup to the regular tankage. It's difficult for me to imagine any
other purpose unless they used it as a deck locker.