The two were headed north on Broad Avenue when Yusuf Bakmaz missed the split to Grand Avenue on the left around midnight June 24, Ridgefield Police Chief TJ Gallagher said.
The teen's white 2002 Ford Mustang barreled over the island, clipped another vehicle and swerved directly into Karden, which opened in April at the site of the old Chan's Dragon Inn.
Bakmaz -- a sophomore who majored in computer science and made the Dean's List at Montclair State University -- was pronounced dead at the scene.
His girlfriend had gotten out of the car and was taken in serious condition to the trauma unit at Hackensack University Medical Center.
Occupants of the clipped car weren't injured, Gallagher said.
Borough police and firefighters were the first on the scene. An ALS unit from HUMC responded along with rigs from NJ Mobile Health and Holy Name Medical Center in Teaneck.
The county sheriff's Bureau of Criminal Identification collected evidence before firefighters removed the body and turned it over to the county Medical Examiner's Office. The Bergen County Prosecutor's Fatal Accident Investigations Unit was notified.
"All units worked extremely well, making sure the scene was kept intact and the driver was removed with dignity," one responder said.
The Mustang, which responders initially covered with a tarp, was towed from the scene.
Ridgefield police are awaiting toxicology reports as part of their investigation into what happened, Gallagher said.
Witnesses told police the vehicle was speeding, he said.
Jo Fehl took the photos and contributed to this story.
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