Riverside road parallels the meander of Rockaway river near the downtown area.
This is what it looks like 2 days after Sandy
This is somewhere along Riverside....
This is downtown area...
Between the two, I would still pick Denville. You just have to be careful to research the flooding situation. It is a nice and reasonable priced town with a good school. I have friends that also live in Rockaway and they seem happy with their location but it lacks some of the small town character that Denville possesses.