At about 6:15 a.m., firefighters responded to the incident in the eastbound lanes of I-40 at MLK. A car reportedly went off the road, down the embankment and into an offshoot of the Oklahoma River.
The car, a maroon, older-model Pontiac, was mostly submerged when emergency crews arrived at the scene.
Officials said the driver was able to get out of the car and call 911. He has been transported to the hospital in an unknown condition.
The cause of the incident is under investigation.