WHERE IS IT TODAY?
There were two trimarans built for WATERWORLD. A sailing trimaran was built for the sailing scenes, and a transforming trimaran was built for the transformation and trawling scenes. Of the two trimarans built for the movie, the sailing trimaran is located in the lagoon at Universal Studios Florida and the transforming trimaran is located here in San Diego in San Diego Bay.
Below is the transforming/trawling trimaran (in trawling mode) as it appears in WATERWORLD. Note the Mariner (Costner) on the bowsprit.
Below is the transforming trimaran as it appears today. This is a photograph I took in July 2000 of the boat moored at an end slip in a marina in San Diego. The transforming trimaran is privately owned and you can see it obviously no longer has the "eggbeater" blades, the bowsprit, and a few other items that have been removed. The netting between the hulls remains though.
As of 7 November 2005, the Transforming Trimaran appears as though it has been painted white and fitted with a regular fullsize mast and jib by its owner. It appears to have been converted into a regular trimaran for normal sailing use. I will take and put up photos if I can.
Below is the sailing trimaran as it appears today located in the lagoon at Universal Studios Florida. This is a photograph taken by Ronald Weber (who sent me this image of the sailing trimaran).