OAKLAND — Oakland police are investigating a single-vehicle crash that killed a Winslow woman Saturday night on Kennedy Memorial Drive near the Oakland-Waterville town line.

Katherine Poulin, 48, was driving east toward Waterville from Oakland in a 2013 Mazda sedan at 11:15 p.m. Saturday when the car left the roadway and she was ejected, according to Oakland police Chief Rick Stubbert. The car came to rest in Waterville, he said.

Though Stubbert said identification documents showed her last name as Bouchard, her sister, Chrystal Currie, told the Morning Sentinel Monday that she had changed her name back to Poulin after her divorce in April this year.

She was pronounced dead at the scene, Stubbert said Monday morning in a phone interview.

Currie spoke lovingly of Poulin Monday in an email.

“Kathy was a beautiful person, inside and out,” she said. “She cared deeply and loved wholeheartedly.”

Currie said she and Poulin grew up in Vassalboro and had no other siblings.

“She was my best friend,” she said. “She worked at Northeast Lab in Winslow for the past 20 years. She has one son, Tyler, who she loved so very much. She raised him to be a wonderful, smart, hardworking young man. We just lost our mom to cancer in August. She is now with her.”

Kennedy Memorial Drive is a major east-west artery that is also state routes 11 and 137.

Stubbert said police are investigating what may have caused the crash. Oakland police Officer Todd Chilton is the primary investigator, he said.

Both Oakland and Waterville police responded to the crash, which occurred near Central Maine Ford, formerly known as Ray Haskell Ford, just west of Interstate 95 and the entrance to FirstPark.