I stayed one night at Salmon Creek Falls in April, 2013 and was stoked on how sweet-sounding the falls were from the campsite we snagged. It was early in the season, so there was only one other family there. There are a few excellent spots on the creek side of the campground with decent access to the water. Plus, the drive from Eugene is a beautiful one. I can imagine this first-come campground fills up quick in the summer, but at least for early or late season it's and awesome place for a quick jaunt out of town with a nice level of seclusion.