In general, marmots may damage gardens but don't harm humans if they aren't approached. Since they are wild animals, however, they might hurt someone if they feel threatened by people or pets who get too close. Also, they may carry ticks that cause disease in humans and pets.
If you decide to get rid of the marmot, it would be good to look for an AnimalKind pest control company near your home. The BCSPCA website has a page where people can enter their location to find a company. AnimalKind companies remove animals humanely, live-trapping them whenever possible and transporting them to a new habitat. There may be other companies in your area that also live-trap animals.