The 22-year-old woman, who has not been identified, escaped the sinking car through a window and swam to shore, Oakland Police Officer Robert Cooper said.
The woman was driving westbound in 3200 block of Alameda Avenue at 4:50 a.m. when her cell phone rang. As she was reaching for the phone on the floorboard of the 2007 Ford Escort, the car swerved into eastbound lane, through a cyclone fence, down a 20-foot embankment and into waters of the Oakland Estuary.
The tide was in at the time and the car floated about 200 feet west, where it ended up in pilings under a house in the 3200 block of Alameda Avenue.
The woman went to the hospital for complaints of pain and cuts to her face, Cooper said.
She works for Brinks Inc., about five blocks from where the car went off the road, police said.
The U.S. Coast Guard has been notified of the incident -- a small sheen from the car has been spotted drifiting eastbound down the estuary. Officials are determining how to remove the car from under the house.