https://youtu.be/S3toozoKy48 I saw a few of these up at Alice Lake Provincial Park, just north of Squamish. From a very rudimentary search and guesswork on my part, my initial guess would be Monadenia fidelis (Pacific Sideband)? Any help is greatly appreciated!
It looks very similar to Helix pomatia very common in my old country, however they are European species. May be someone brought them here, though, they are probably quite tasty.
I started to have doubts after looking at some more pictures on the Net. Helix pomatia look much flatter than yours.
I'm still thinking it's Monadenia fidelis. I'm changing the video title to that until such time I learn better : )