The Press-Enterprise reports a Canyon Lake, California resident was setting up their 1939 Packard on a boat ramp for a photo shoot on April 9 .

For reasons unknown, the owner left their vehicle on the boat ramp.

It's unclear whether the owner engaged the handbrake, but the vehicle nevertheless rolled into water around 6m deep, becoming fully submerged.

At around 8am, a member of the Canyon Lake Community Patrol reportedly called the Canyon Lake Fire Department after they saw an oily sheen on the water and played back surveillance footage of the sinking.

The fire department responded, requesting assistance from the Cal Fire/Riverside County Fire Department and the Riverside County sheriff's dive team, suspecting there could be someone in the vehicle.

At around 8:20am, the owner returned and informed emergency services personnel the vehicle was unoccupied.

"He was very emotional," Canyon Lake Fire Chief Jeff LaTendresse said. "It was like his baby."

Pedro Gonzalez, automotive curator of Carey's Fine Automobiles in San Bernadino, told The Press-Enterprise the vehicle is valued between US$25,000 to $40,000 (A$38,235 to $61,177).

He noted the water-logged interior and wiring would make it difficult to save.

Riverside County environmental health workers were called to the lake to handle the clean-up, installing booms to prevent the further spill of oil.

Content originally sourced from: CarExpert.com.au