According to Kingsport Police Officer Dale Farmer, witnesses said the driver appeared to be eating breakfast and was distracted.
Police say Jonathan D. Casey, 31, 981 Old Gray Station Road, was westbound in a 1996 GMC box van on East Stone Drive when the wreck occurred.
As the van approached Reedy Creek Bridge, it went to the right and struck the guard rail, police said. He then overcorrected and went airborne over the bridge railing. The van landed upright in the creek bed and Casey was ejected through the front windshield.
Casey was in critical condition as of Friday afternoon, according to a Wellmont Health Systems spokesman.
Police said charges are pending.
The crash remains under investigation.
CLICK THE BOX BELOW for a video report from the scene.