RCMP Sgt. Darryl Little says emergency crews were called out to Slocan Lake on Saturday, where they found the woman unconscious and rushed her to hospital.
She later died and grief counselling is now available at a New Denver elementary school.
A rescue operation continues amid calm weather for the three other occupants of the canoe, aged between 16 and 21.
Little says three of the people are from the nearby village of New Denver and one is from Gibsons.
He says the water is ice cold and glacier fed and that police, fire and search and rescue teams continue to sweep the area for survivors.
Little says none of the youths appeared to be wearing life jackets and that conditions were relatively calm when the boat overturned Saturday.