Two large barges being moved both up and down river by tugs. A lot of containerized freight is staged up river for transport to Alaska. I know of two large operations, one either side of the river, that specialize in collecting and forwarding freight to Alaska ( one of which I actually did a job interview for about 30 years ago-fortunately I didn’t get the job). It’s not unusual to see vehicles of all types perched on top of a stack of containers heading north. What I found fascinating is that these barges draw little water and leave hardly a noticeable wake in the path. A small speedboat, on the other hand, will create all sorts of noise and a wake that sends the ducks scurrying and bobbing about :-).