Could someone Iive in the United States and work in British Columbia?

Yes it would be possible. I know several of people who live in the Lower Mainland/ Fraser Valley area who live in Canada, and then work in the states. It is very possible. They give you those Nexus cards, and then you're just able to go through like that, instead of having to wait through those long line ups, but you have to pass some rigorous stuff first.

Yes, an associate of mine works in Richmond, BC and lives in Bellingham, Washington. He has a Nexus Pass to help facilitate getting through the border faster and avoiding the line ups in the summer months. He is an American Citizen and has a Right to Work Permit for working in Canada. I believe the necessary paperwork can be obtained from any border crossing office.

Sure, lots of people do it (and vice versa, living in BC and working in the US). You have to have the proper work authorization unless you're an American citizen, and preferably a Nexus card to speed up the border crossing.

It would be an awfully long commute...You could be an American citizen and live in British Columbia and work.