Where are you cooking at in your BWS? Your best chance for bark is at the very top where its the hottest. If you are looking for a very firm and thick park you will have a hard time if you are using water in the pan. You can try sand, lava rock, or foil balls to create a drier environment.
BWS G2 Party w/custom cart, Thermapen (does yours have flames.......mine does so be jealous)