HONOLULU -- Speed and alcohol may be factors in a one-car crash in Oma'o on Kauai on Wednesday that left a 21-year-old man dead, county officials said.

The driver, identified as Preston Ramson, was driving west in a vehicle on Kaumuali‘i Highway when his vehicle ran off the roadway, struck a utility pole and the end of Oma’o Bridge and then fell about 40 feet to the bottom of a ravine, officials said.

Police found the vehicle at about 1:40 a.m.

Officers closed both lanes of Kaumuali‘i Highway for about six hours during their investigation and recovery.

The death is the eighth traffic fatality on the Garden Isle so far this year, officials said.