We were there last summer and think its the nicest KOA we have stayed at. Next time we will get a backin site on the river. There is a real good resturant 1 block away too. I've got pics but unable to post here.
We stayed there late July last year. I don't remember the campsite (if I had a map I could tell you) but it was the second to the last site along the river as you drive around the loop. The first site they put us in was muddy because they had been getting a lot of rain (you can see how swift the river is) and luckily we were able to relocate to the other spot which was perfect. We liked the campground and would definitely stay there again.
Youtube has a video or two of the Townsend KOA. Also there are a few pictures on Tripadvisor, but I don't remember if they have any pictures of the sites. We're staying there at the end of May, so I've also been looking for info on-line. We're staying in a camping cabin.
I just made reservations for sites 122 and 123 October 20-28. They are supposed to be on the river and have W/E. Management was super nice and assures us that even though its really "woodsy" back there we should have no problems getting in or getting slideouts out. Any more pics floating around out there, especially of the water and electric sites I would love to see them.