All the victims were from Warren.
Killed were: Alexis Cayson, 19, Andrique Bennett, 14, Kirklan M. Behner, 15, Daylan Ray, 15, Brandon A. Murray, 17, and Ramone M. White, 15.
The survivors were Brian K. Henry, 18, and Asher C. Lewis, 15.
WFMJ-TV, Youngstown, reported police said the youths' Honda Passport veered off the left side of a road, hit a guardrail and overturned before ending up in the water about 7 a.m. Two occupants got out and called 911, the TV station said.
WKBN-TV, Youngstown, reported dive teams were called to the scene to help extricate the bodies.
Ohio Highway Patrol officials said none of the teens appeared to be wearing a seat belt.
WKBN-TV said police did not believe alcohol was a factor in the crash, but did not say what caused the accident.
"My heart and prayers go out to the families. It's a horrific morning," Warren Mayor Doug Franklin said.