Thiess, as part of the West Gate Freeway Alliance, was awarded the Monash-CityLink-West Gate Upgrade contract for VicRoads. The contract was one of the largest state-funded road project in Victoria's history, designed to improve traffic flow and safety along one of the State's busiest routes.

The West Gate Freeway Alliance included Thiess, VicRoads, Baulderstone Hornibrook, Parsons Brinckerhoff and Hyder Consulting.

• a new elevated road structure joining Kings Way to Freeway
• new traffic ramps over Montague Street
• an additional dedicated exit ramp from Bolte Bridge to the Freeway
• widening of the Freeway between Todd Road and Montague Street, and
• a complete redesign of the Montague Street interchange.

The Moncash-CityLink-West Gate Upgrade has reduced peak hour travel times, improved reliability along the freeway, and improved driver safety. Melbourne now has one of the most advanced freeway management systems in the world. The co-ordinated freeway management system also manages entering traffic to minimize stop-start conditions brought about by a high volume of traffic or incidents. The system also enables faster recovery from a freeway incident.