The coast guard said rescue boats quickly retrieved her from the water about 8:30 a.m. PT on Friday, and she was airlifted to hospital. Her condition is not known and it's not clear how the woman ended up in the water.
When asked whether she jumped from the ferry, BC Ferries spokeswoman Deborah Marshall said "it is our understanding [the woman] did not fall."
Officials have released no further details.
The incident interrupted ferry travel between southern Vancouver Island and Vancouver for much of the day.