I think RG is very close to Woopi and woopi doesn't have the same problems as Coffs in terms of major waterways all converging and trying to exit into the ocean in a narrow band.
I just called my old china plate in woopi and had a chat to him about it, he says he's as snug as a bug.
Not sure how close RG is to woopi creek, but very few people who live behind woopi build close to it.
This is a pic from last November up at the rain forrest standing in Woopi creek. I reckon today, the water would be a foot above my head.
The hardest heaviest rain I've ever seen has been up there, but I've never seen it flood unless there's been a king tide with it.