Also curious of the basis for that "safe to drink" thing (I know some certain kinds are very sensitive to the water conditions, but is that really something that can be extended to the entire family?). Aside from that as others have said his survival skills are not very good. He doesn't boil the water to be safe, and I am not entirely certain but I remember being taught that uncultivated (aka wild) crustaceans are potentially dangerous to eat. At least I remember being told about it being wise to avoid consuming sweetwater ones found in the wild. Dont remember if the cause was possibility of disease/parasites, or if it was related to toxins of the lake accumulating in them, or what ever else the reason might have been.
EDIT: also, why is he talking about smog when he mentions the stars, as opposed to the much more prevalent and noticeable light pollution of modern cities?