Since you are not getting much response from those with better knowledge of what goes in Canada than I, I will at least try to keep your ball rolling.

My very simple answer is - if you don't feel that spending your entire future professional life as a technologist is going to be enough for you, then get yourself to University (or at least get the qualifiactions that you need to be an engineer) if there is any feasible way that you can.  Otherwise you run the risk of a very long time wondering 'what if...'.

Is there any way in which you can get the qualifications that you need on a part-time basis? That might reduce the debt and might also provide a way to service it.  One of the most practically adept engineers that I know did that, but part-time study is not an easy option.

The name of the institution you attend may well have some influence on your chances of getting satisfying work in the early years after graduation.  But after that, what will matter much more is what you make of your opportunities for gaining good experience after, and how well you perform as a professional engineer.
 
I honestly can't get my head round a student debt of $70000.  On a rough assessment, it took all of my first 12 years after graduation to GROSS $70000.  I can only wish you the very best of luck in coping with it.

Having recently finished my degree in Engineering in Canada,maybe I could offer something. If you are sure that being an engineer is what you're after then I suggest making sure your college has an affiliation with a university to make sure that you recieve proper credit for the courses you take now. Structural techs seem to be more involved with material testing and construction supervision than comprehensive design, so if you are a "hands on" type of guy this could be a rewarding career. If you want to be more involved with the design and project management, I would suggest taking your studies to a university.

From a monetary point of view, if your student loan is that high, you will probably never recover the costs of University after college. Paying $45,000 and not working for the extra years it would take you for the degree would not be worth it for money alone.

Hope this helped.

I would go for the degree. It just doesn't hurt to know more right?