I take Duluth packs on all my canoeing expeditions and Ill say they are very water resistant, but not water proof. I always put everything which "has" to stay dry within ziplock or trashbags...toilet paper comes to mind...
a few week of portaging and paddling into the wilderness away from civilization and your toilet paper gets wet is a mistake you will only make once...
Yes I know the feeling
I put everything in the 'Duluth Pack Liner system' - technical name for a large clear polythene bag
When the canvas pack gets soaking wet, it always amazes me how quickly it drys out
