This design and construction project consisted of the upgrade of approximately four kilometres of Yan Yean Road between Diamond Creek Road and Kurrak Road in the suburb of Plenty.

The works consist of the duplication of Yan Yean Road to four lanes, two lanes in each direction, and the upgrade of major intersections. This was a complex design along a constrained corridor with existing services, protected vegetation, and hilly terrain.

The project included

• Road works, earthworks, retaining wall works, street lighting, safety barriers, drainage improvements, new shared paths, traffic signals, and associated works.
• Six intersection upgrades (Diamond Creek Road, River Ave, Memorial Drive, Browns Lane, Kurrak Road, and Nillumbik Shire Council Recycling and Recovery Centre).
• Widened and installed safety improvements at the Mackleroy Road intersection.
• Relocation and protection of utility services.

Features of the project include

• Safety barriers.
• Shared paths for pedestrians and cyclists.
• Stormwater drainage design.
• Pavement design.
• Dedicated bus lanes at the Yan Yean Road and Diamond Creek Road intersection.
• Replacement of the existing roundabout with new traffic signals at the Yan Yean and Kurrak Road intersection.
• Traffic modelling.
• Six intersection upgrades.
• Extensive retaining walls and earthworks.
• Straightening of road alignment for improved visibility.
• New refuse islands to connect pedestrians with bus stops.
• Relocation and protection of Utility Services.
• Public lighting and traffic signal design.

Sustainable design measures adopted include optimised earthworks to reduce the extent of import and export of materials from the site and WSRD and drainage design to accommodate high flood runoff were the remedial measures introduced to minimise adverse flooding impacts to neighbouring properties.

BG&E’s innovative design saved over 1000 trees that were originally planned for removal by refining the road alignment and reducing the overall footprint of the works. Any trees and plants that were impacted by the road widening works were replanted. Wood from trees that were cut down was made into benches and sculptures, enhancing community spaces.

The project also introduced dedicated bus lanes and undertook intensive traffic modelling in SIDRA and VISSIM to improve intersection performance.

BG&E optimised the existing road reserve and optimised lane transitions to reduce bottlenecks and potential queuing through the intersection.the

BG&E’s innovative design solution for the Diamond Creek and Yan Yean Road intersection increased the design life of this intersection by approximately 10 years over the reference design (by others).