From the carnival website:
"Carnival Cruise Lines yesterday announced that it has changed its beverage policies. Passengers are no longer allowed to take nonalcoholic beverages onboard, including water. And they will now be limited to one bottle of wine per adult upon embarkation only. The new policy also warns that ship personnel will confiscate and discard any outlawed beverages. Carnival will continue to charge a $10 corkage fee per bottle for personal wine consumed in the dining room ($14 for the Supper Clubs). Carnival spokesman Vance Gulliksen said the rule was changed because security and embarkation personnel were reporting that passengers were "abusing" the previous guidelines, which allowed cruise-goers to carry on board a "small quantity" of nonalcoholic beverages, wine and champagne, both at embarkation and while in port. Asked whether the abuse related to passengers carting cases of bottled water aboard, or toting suitcases full of wine, or smuggling vodka disguised as water (hard liquor has never been permitted as a carry-on), Gulliksen said the issue related to "excessive amounts of nonalcoholic beverages being brought on board."