Senior Constable Dean McLaren, of the Hamilton police highway patrol unit, said the rollover happened soon after 7am when the combination was turning right from the Glenelg Highway onto the Edenhope-Coleraine Road.

The accident on the west side of the Coleraine occurred while the truck was heading to a wind farm development.

"The rear of the trailer gone off the road on the soft edge and the trailer and load has tilted and taken the prime mover with it," he said.

"It's all happened pretty slowly. No one was injured, including the driver in his 50s."

It was the third accident involving a wind farm truck and trailer in the past couple of months.

A fatal accident near Dunkeld last week involved an unladen wind farm prime mover and trailer.

The 85-year-old Melbourne driver of a four-wheel-drive died after he veered into the truck.

And in mid July 160 customers were left without power after a truck and trailer combination carrying a turbine blade collided with a power pole in Glenthompson.

Senior Constable McLaren said the length of the vehicle in today's accident, from the front of the prime mover to the rear of the trailer, was 85.5 metres.

"It's a special purposes trailer operating with front and rear pilot vehicles along a designated route," he said.

"Heavy haulage will remove the blade and then right the prime mover and trailer. That process will take hours and the road is expected to be blocked at that time.

"Traffic management and speed restrictions are in place and the process is being supervised by VicRoads officials.

"We just ask that all drivers either avoid the area or obey the restrictions," he said.

At 9.45am: A long truck load hauling a wind turbine blade has rolled on the Coleraine-Edenhope Road just off the Glenelg Highway at Coleraine.

Police said the 65-tonne load was on its side but no one had been injured or trapped.

Police are controlling traffic around the accident scene.

Diesel is leaking from the prime mover but it's understood that Country Fire Authority officers are managing that issue.

The accident happened soon after 7am.

Earlier: A wind farm truck has rolled over on the western outskirts of Coleraine.

Emergency services are still on the way to the accident scene.

It's expected to take some time for the road to clear.

Drivers in that area are advised to avoid the Glenelg Highway intersection with the Coleraine-Edenhope Road.

More to come.

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