I doubt that copper is responsible for the blue color of lakes in BC.
While copper is certainly found in BC, and while at locations where
it is found, some does dissolve in groundwater, most blue lakes are
relatively pure water. I don't know why lakes or glacier cravasses
are blue. The story on the silt (properly called "glacial flower")
in Lake Louise is that it is microscopic flakes of rock that erode
due to the motion of glaciers, and failing that, to the freeze-thaw
cycle. (As I said, this is a story; I have no reason to believe it.)