The victim was extricated from her SUV and transported by ambulance to Wallowa Memorial Hospital. Postal officials responded to collect the remaining mail in the vehicle.
The crash occurred after a nightlong snowstorm coated the west moraine of Wallowa Lake within Wallowa Lake Rural Fire Protection District.
The SUV was headed downhill when it apparently slid into the right-hand ditch and flipped onto its right side.
Joseph Fire provides services to the fire district under contract.