A 10-kilometre stretch of the Hume Fwy melted on Friday and Saturday, as the region sweltered through the hottest two-day period this summer.
The speed limit is set at 60km/h due to the bleeding of the road surface which occurs when the bitumen becomes reactivated by warm temperatures and becomes soft and sticky.
A Vicroads spokesman said on Monday there were traffic contractors fixing two lanes — one on the southbound, the other on the northbound lane, and speeds would be brought down to 40km per hour while the works were happening.
Further investigation and repair works will take place throughout the next few days and there will be delays at times through this stretch of road.
A south-bound stretch of the Goulburn Valley Hwy between Tallarook and Broadford also started melting because of Saturday’s extreme temperatures.
Traffic delays were caused for those travelling south, with the speed limit changed to 60km/h as Vicroads repaired the road that suffered from surface bleeding.