Police investigators have been told a car was leaving a carpark of the tourist spot known as the Giant Koala on the Western Highway about 3.20pm when it was involved in a crash with a truck.

Emergency services arrived a short time later but the driver of the car, believed to be a woman in her 30s, died at the scene.

The driver of the truck who was uninjured, stopped and has spoken with police.

The investigation into the crash is ongoing.

The Department of Transport has confirmed drivers along the Western Highway travelling through Dadswells Bridge are experiencing heavy delays, but the road has not been closed off.

A spokesman was unable to confirm how long drivers would likely be held up.

Earlier in the day a rescue operation was underway after the incident occurred about 3.26pm and a air ambulance was called in.

The woman's death brings the state's road toll to seven people.

Anyone who witnessed the crash or with further information or dash cam footage is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential report at www.crimestoppersvic.com.au