This is something to talk to your CFRC recruiter about. CF policies change from time to time and its better to get it from the authority.
During the second week of BMQ (at least for reg force), the recruits go for a fitness assessment. Its alot like the application process fitness
test, shuttle run, sit-ups, push-ups but with a swimming evalutation. To pass the assessment, the recruit must successfully perform at least the
minimum requirements of the test (#of push-ups, # of sit-ups, VO2 calculation per age category, and tread water, make your way accross
the pool, and a feet first dive with life jacket on).
In my platoon, there were a number of recruits that either did not know how to swim or could swim very poorly. They "failed" the first
fitness test and were directed to take a re-test in week seven. Of those recruits, a few passed the re-test but some still could not
pass the swim test. They were marked as "non-swimmers" and they'll get instruction at the training or gaining unit later. So the swim
evaluation was not a BMQ/course pass or fail.
No matter what MOC or what element you go into, you'll have to know how to swim. PT is mandatory and you'll find yourself in a pool,
a lake, an ocean at some point and the skills needed for swimming are important. If you got the time, its in your best interest to learn
at least the basics of swimming before or after BMQ, treading water, a simple crawl, and loose a fear of the water.