Hey,
Well I am also a keen kayaker, as was heavily involved when at Sheffield Uni.
As for storage....
Your right, that keeping the kayak in your room would not work, however, this depends on what halls you are in. I live in Lockington (one of the older halls) and there is plenty of room.
I will investigate other storage options for you and get back to you. If you are on msn it would be easier to send me a private message with your email etc
Darren
p.s. be aware that practice sessions are on main campus area as the pool. No outside boats allowed. but you will need to sort transportation of your boat if you go on trips etc