Sarah Townsend, 18, vanished back in early May. Her car was found abandoned in Green Acres Park in Burlington Township.
Five days later, officials found her body in the bottom of Sherman's Pond.
On Tuesday, Burlington County Medical Examiner Dr. Ian Hood, released the findings of his investigation, concluding Townsend committed suicide.
Hood also confirmed that a suicide note was in her car and that Townsend had significant levels of cocaine in her system.
Soon after her body was found, her cause of death was determined to be from drowning.
There were no signs of foul play.