Traffic is flowing again after more than a tonne of yoghurt was spilled on the Federal Highway during a van rollover north of Canberra.

The van crashed in wet weather shortly before 8:30am on Wednesday at Woologorang, throwing about 1.5 tonnes of yogurt in hundreds of tubs onto the road.

Two people in the van were cleared of injuries by ambulance crews at the scene.

It was estimated 80 per cent of the van's load was spilled.

The NSW Environmental Protection Agency was notified, and fire crews helped to sandbag sides of the road to prevent the dairy from being diluted by rain and entering waterways.