TheArtificial Reef Society of British Columbia has been very successfull at procuring, preparing, and placing retired cold war era destroyers. These are becoming living cold water reefs. There are literally 100s of known shipwreck sites and 1000s of shore dives for all levels of certification.
Though it seldom dips below freezing in the winter,it does rain a little more than most people are used to. The bonus of diving in the winter is reported viz in excess of 100'. Dry suits are recommended year round.
The scenery in a word is spectacular.
Underwater Council of British Columbia
Northern Vancouver Island
Central Vancouver Island
Southern Vancouver Island
Adventurers Dive Log