Which climbing tower? ... the Alpine tower which is back behind the football field isnt really open to students.... They sometimes have events where they do open it up to students for a fee, but the last time they did that was last year during exams for 5$. Haven't had another opening for students since then.
The climbing wall in the pulse requires a pulse membership to use, you can find the hours here;
http://www.marauders.ca/sports/2011/...rs.aspx?id=218
... sorry just saw you meant the Alpine tower..... Like I said its not really opened up to students, its usually booked to groups and stuff... I think you need at least 10-15, and there is a decent fee associated to it. Maybe, if you get a bunch of friends together you might be able to book it for use?? .. Try contacting them to see if its possible