
A 39 kilometer toll motorway was constructed on budget (A$2.5 billion) and five months ahead of time. It was opened in June 2008. This project involved 17 interchanges, 88 bridges and twin three lane, 1.6 km tunnels. It has three lanes in each direction for 33 km and two lanes in each direction for 6 km. EastLink connects the eastern suburbs of Melbourne and was delivered under a Public Private Partnership (PPP) arrangement by Connect East (listed on the Australian Stock Exchange) for the Victorian Government agency, Southern and Eastern Integrated Transport Authority (SEITA). Project development was undertaken by two of Australia’s largest contracting organisations, Thiess and John Holland, in a joint venture arrangement.

Background

Performance Based Specifications
Right at the tendering stage, considerable thought was given to encourage competition in the private sector to achieve the best outcome for the Motorway. One of the key elements was devising the performance based specifications that would make it clear what was needed without specifying how it should be achieved. Interestingly, the document produced was a fraction of the size of a normal specification, yet spelt out the State’s requirements. It had set targets such as a 100 year design life for structures.
The specifications provided for the road to fall within a certain route envelope but the exact alignment was variable; the shape of the interchanges was open to variation, and the pavement had to perform to a certain standard yet its make-up was not prescribed. Urban design had to be a part of the mix and the bids had to show that they reflected community expectations along the route. The requirement of the tolling system was that it had to be fully electronic and it had to be interoperable with other electronic toll roads in Australia. Toll levels were not prescribed with the only requirement deemed that escalation had to match movements in the Consumer Price Index (CPI) with changes being applied annually. Both design and construct contracts were self-monitored by Quality Assurance (QA) procedures and checks as work progressed.
The Independent Reviewer
The Independent Reviewer (IR) was appointed jointly by the Government and the Concessionaire. The IR’s role involved a general overview and reasonable checking in order to be satisfied that the various detailed checks and monitoring processes were carried out correctly and, in order to ensure compliance with the design construction requirements. This organisation reported jointly to the two employers, ensuring impartiality between the two client sides. All design and construction information developed by the contractor had to be provided to the IR who had the responsibility to certify completion before the road could be opened.
Working Arrangements

Another efficient process implemented was that construction itself was subjected to Quality Assurance (QA) processes. The contractor was responsible for auditing and guaranteeing its own systems according to appropriate QA standards.
The Construction Challenge
The Tunnel: The construction of the $600 million twin tunnels was a complex operation. The diameters of each tunnel exceeded 16 meters with special ventilation buildings at the exits. These buildings incorporated large fans to capture the air leaving the tunnel and the car exhaust contained in it. The excavation was undertaken by four large machines known as road headers. These have a rotating head with cutting teeth at the end of a pivoting boom for cutting away the material at the heading of the tunnels, Figure 2.
The tunnel was also fully “tanked.” This means that it was made watertight, rather than allowing water to trickle in the tunnel and then draining it out. This was done by having a circular cross section for the tunnel and using a drainage blanket and waterproof lining, Figure 3. An overview of the tunnel is presented in Figure 4.

The Bridges: For most of the 88 bridges, pre-cast reinforced concrete units were used for speed, quality and economy. In the case of an operational railway line which overpassed the new road, the construction schedule was planned in such a way that it was closed only for a very short time. This was achieved by first, installing the foundations and final columns of the new bridge and then the crosshead supports for the bridge super structure.


A 500 tonne mobile crane was used for lifting heavy crossheads and beams for bridge construction throughout the project. Some of the bridges including the rail bridge over the motorway are shown in Figure 5.


Noise walls: Over 13,000 noise wall panels were installed. The sections of noise walls were different in shape and colour to improve the visual appearance and better integrate with the surrounding environment and look as natural as possible. Typical wall panels, including transparent sections, as shown at Figures 7 and 8 were manufactured precast at the precast fabrication yard.

Road construction: The construction work involved three lanes in each direction for 33 km, two lanes in each direction for 6 km. This involved over 7 million cubic metres of earthworks, 1.1 million tones of asphaltic concrete, and 380,000 cubic metres of concrete. Asphalt laying was a highly coordinated large scale logistics exercise in its own right during construction (Figure 9).

Concluding Remarks
EastLink has proven to be one of the most successful toll road projects in Australia delivered as a Public Private Partnership. Thirty months after opening, traffic growth is continuing at an incredible 10% per annum and neighbouring communities are praise worthy of the delivered outcomes.
Key success factors included clarity in contractual documentation and understanding of the roles of respective parties, early establishment of organisational structures, the rapid recruitment and training of human resources, establishment of a project specific pre-casting yard, bridge construction using standardised pre-cast elements to the maximum extent possible, establishment and retention of highly effective working relationships between the project parties, continuous community engagement and the early resolution of construction issues, as well as environmental enhancements and the provision of urban amenity outcomes throughout the corridor.