The middle fork of the American River is a great place to have fun. The canyon walls on either side of the river offer great scenery in the calmer sections. The class IV rapids provide plenty of excitement for folks trying to lollygag in the warm weather.
Since the American River is one of the few rivers in CA that is dam controlled and raftable, the drought is a non-issue!
If you go, try to stay in the boat, unlike the unnamed fellow in the picture.