I've read about the ferries between Valdez and Whittier. Is there a separate service that uses a high speed catamaran or does the fast ferry use a catamaran? How long does the crossing take? We are trying to get from Valdez to Whittier to join our cruise this August. Also is it possible to drive from Copper River to Valdez and take the ferry/catamaran to Whittier all in one day?