There's a Gold Membership that includes basic membership + unlimited access to the pool. I think it's roughly £140 per year (or less, there were a few offers, so I could be mixing them up). In any case, for a bit more, you can also get unlimited access to the pool AND sauna.
I'm getting a Gold Membership, but with unlimited access to the gym and free weights room instead (£134, IIRC). I did the figures, and overall it's good value for money (if you intend to use the gym at least three times a week). I'm guessing that the Gold Membership with the pool access should be a good deal too (especially if you want to go everyday). There should be a form about all this in your freshers 'Welcome Pack', and it lists all the costs there. I already sent mine in, so I can't check.