Tugun Bypass—Motorway and Tunnel

Tetra Tech’s High Performance Buildings Group provided communications, technology integration, mechanical, electrical, plumbing, security, and fire engineering and protection services for the Tugun Bypass project in Queensland, Australia.


  • Size: 7.5 kilometers (4.7 miles)
  • Construction Cost: AUD$543 million (USD$367 million)
  • Client/Owner: PacificLink Alliance
  • Architect: Hassell
  • Contractor: Abigroup Contractors (now Lendlease)
  • Completion Date: 2008

The aim of The Tugun Bypass project was to improve the Brisbane-to-Sydney traffic corridor along the Pacific Highway. The purpose behind the project was to eliminate congestion on the local roads through Tugun, with a new, north-south-running motorway section between Currumbin and Tweed Heads.

The 7.5-kilometer (4.7-mile) motorway link includes a short tunnel capable of withstanding extension of the Gold Coast Airport runway, which it now runs beneath, and acoustic screening of the carriageways from existing residential properties. Completed in mid-2008, the Tugun Bypass has provided a new, motorway standard link between Queensland and New South Wales easing congestion and reducing travel times for tourists, heavy vehicles and local traffic. The bypass is four lanes wide, with provision for upgrading to six lanes and a rail line in the corridor. The bypass was expected to take 55 percent of traffic off the existing Gold Coast Highway by 2017 and reduce travel time between Currumbin and Tweed Heads West to five minutes. Without the bypass, delays of up to 30 minutes on the Gold Coast Highway would have been common by 2017. Current monitoring shows that approximately 57,000 vehicles use the bypass every day.

PacificLink Alliance selected Tetra Tech to undertake design of all the tunnel and motorway services for the bid phase. On becoming the successful bidder, Tetra Tech also provided detail design and construction phase services. The AUD$543 million (US$367 million) project was jointly funded by the Queensland Government (78 percent) and the Australian Government (22 percent).

Although the tunnel is short (less than 1,312 feet or 400 meters), the design criteria involved not only all the issues that need to be addressed for longer tunnels (automatically controlled multi-stage lighting; secured power supply; air quality; fire incident detection, suppression, and smoke management; secured fire water supply; traffic management; and motorist and emergency services communication) but also higher-level criteria to meet the demands of a motorway with no restriction on goods carried other than flammable gases and explosives.

Most Australian tunnels are designed for 50 mph (80 km/h) speed; the Tugun motorway is designed for 62 mph (100 km/h). This requires higher intensity tunnel lighting and design to ensure stopping distances are safe.

The design of the Level 3 high-voltage power supplies was undertaken by Tetra Tech, in consultation with Country Energy. These designs cover the lighting, ventilation/smoke management systems, and fire services and safeguard against power outages.