Major Crash investigating Sawyers Valley dam crash after driver veers off road and into water east of Perth

A man behind the wheel of a car that veered off the road and headed for a dam about 40 km east of Perth he died overnight.

The blue Mitsubishi plunged into the water just off Forrest St at around 10pm on Wednesday.

WATCH VIDEO ABOVE: Car crashes into dam in Sawyers Valley.

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Water officers worked through the night and morning to extricate the driver and the car.

The vehicle was winched out early Thursday afternoon.

The man’s body has been taken by the medical examiner while police work out exactly what happened.

Neighbors heard a whistling sound and ran outside as the car sank to the bottom of the 3m deep dam, which was described as “very murky and very cold”.

“I just saw the tail lights under the water – that was it,” witness Chris Woodward told 7NEWS.

Woodward said he walked around the dam but “couldn’t see any signs of anything else,” so he rushed to call police.

Mary Woodward described the incident as “horribly tragic”.

“You never want that to happen on your doorstep,” she said.

Major crash investigators have closed Forrest St in both directions.