Sift together the flour, baking powder, baking soda, salt, and sugar. In a large mixing bowl, combine the orange zest, orange juice, water, egg, and butter. Add the flour mixture to the egg mixture and mix until the ingredients are just blended. With a spatula, fold in the walnuts and cranberries. Pour the batter into the prepared pan. Bake for 1 hour. Cool in the pan for 10 minutes, then turn out onto a cooling rack.