Monash Engineering works like this:
-For engineering by itself, and engineering as a double degree (except with science), you do a common first year, and then specialise in your chosen area (eg civil) from second year onwards
- For the Eng/Sci double degree, you don't do the common first year, so you can choose your specialisation right from the start. I think this is done so that you have space to do a double major in science.
- There are also specialised engineering degrees which are completely separate to normal engineering. These are aerospace, environmental, mechatronics and some others I've forgotten.
So to do civil, you could do a straight engineering degree or a double degree (not science) and specialise in civil in second year, OR you could do Eng/Sci and start civil in first year.
I can't really comment on RMIT, but I know a few people doing engineering there and they seem to be moving through the content slower than we are at Monash (I'm 1st year doing Eng/Law).
But I would encourage you to come to Monash as the campus atmosphere is much better than at RMIT (excellent student societies and programs like Engineering Leadership Program and Formula SAE)