The Washington State Patrol says a witness, who happens to be a former lifeguard, and a trooper rescued an unconscious driver from a submerged car near Ellensburg.
The patrol says the car left I-90 Saturday, crashed through a fence and sank in a pond with only the roof visible.
The patrol says a passing motorist, Jim Kocker, stopped and swam about 50 feet out to the car but couldn't get inside because the doors were locked and windows were up.
Trooper Jay Farmer arrived, swam out and used a baton to break the window. Both men rescued the driver who was taken to Kittitas Valley Healthcare in Ellensburg.
Trooper Farmer says his heroic efforts are all part of being a trooper.
"Any trooper would have done the same. It's what we do."
The Associated Press contributed to this report.