The 27 kilometre Peninsula Link was the Mornington Peninsula’s biggest infrastructure project and has completed a missing link in Melbourne’s freeway network. The project features nine grade separated interchanges connecting into 11 existing roads and includes three freeway to freeway connections. The construction task involved 45 separate bridge structures, three million cubic metres of earthworks, 380 000 tonnes of asphalt and the planting of 1.5 million trees and plants.
Peninsula Link has significantly reduced congestion on key traffic routes in Frankston and the Mornington Peninsula, particularly during peak periods. The freeway allows motorists to avoid eight signalised intersections and five roundabouts on the Frankston Freeway and Moorooduc Highway.
The project includes a 25 kilometre walking and cycling trail, which was the biggest single addition to Melbourne’s shared use path network in recent years.
In an Australian first for a road project, Peninsula Link was delivered as an Availability PPP. Using this model allowed Peninsula Link to be delivered toll-free, while making use of private sector innovation in financing, construction and maintenance.
Under this delivery method, project company Southern Way is responsible for financing, designing, building, operating and maintaining Peninsula Link over a 25 year period. Upon opening, the Government will make quarterly payments to Southern Way subject to meeting key performance indicators including:
The AUD759 million capital cost of the project includes design and construction, land acquisition, independent reviewer resources, staffing and resourcing for all project parties and provisions for environmental off sets for vegetation impacts.
The capital cost and operational cost risks are the liability of the project company. The contract is in effect a fixed price contract for the finance, design, construction, operation and maintenance of the freeway for the delivery period plus the O&M term. Importantly, under the PPP contract, the state does not bare any liability for a blow out in construction or operating costs. Any increase in costs is borne by the project company and their consortium members.
The mid to late 2000s saw the delivery of one of Australia’s biggest infrastructure projects, the 39 kilometre EastLink motorway. The project transformed travel around Melbourne’s eastern and south eastern suburbs and provided an AUD15 billion boost to the local economy.
During EastLink’s construction, there became a need to address a significant congestion issue facing the Frankston and Mornington Peninsula communities. Population and traffic forecasts following EastLink’s opening highlighted a need for a new bypass road, which would provide continuous freeway conditions from Melbourne’s Central Business District (CBD) to the popular tourist regions in the state’s south east. A planning reservation for a ‘Frankston Bypass’ had existed for some 40 years so it was time to take the project off the drawing board and into reality.
The formal planning study for Peninsula Link was completed in late 2008, with a further six months needed to achieve the necessary statutory approvals. At the same time, a business case was undertaken for the project, which assessed a number of alternative procurement strategies for funding and delivery. The State Government funded Design and Construct (D&C) procurement option was used as the benchmark against which alternative procurement options were assessed.
The world was in the midst of a global financial crisis and innovative thinking was required to get the project up and running. Following a detailed assessment, the State selected the Availability PPP option as the preferred procurement method as it was considered likely to offer greater value for money over the other options assessed.
Unlike the traditional tolled PPP options, the Availability model ensured no direct charges to users of the road. This also favoured the private sector parties as it eliminated the traffic volume risk and revenue associated with traffic modelling projections.
Statutory body, Linking Melbourne Authority (LMA) conducted a competitive tender process to identify a private sector party to deliver the project. The tender process involved five consortia and was undertaken within ten months, with this short time frame lasting as one of the project’s achievements. Following evaluation of the final bids, the Southern Way consortium (consisting of Abigroup, Bilfinger Berger Project Investments and the Royal Bank of Scotland) was selected as the successful proponent. On 20 January 2010, the State executed the Project Deed and Financial Close was subsequently achieved on 8 February 2010. Construction started almost immediately with the project due to be open to traffic in early 2013. The relevant parties under the contractual arrangements were:
The Joint Venture
From a design perspective, Aurecon and SKM decided to form a joint venture six months prior to the project coming to market. Having successfully teamed up on other major projects across Australia, the decision was an easy one as the two consultants had very similar cultures, ownership structures and design capabilities. SKM had built up a strong working relationship with Abigroup having designed many of its major road projects over the previous decade. Another benefit was Aurecon’s involvement in the adjacent EastLink project, which was managed by the same client and delivered using very similar technical and design process criteria.
From the outset, the driver behind structuring the Joint Venture was to achieve the most efficient high performing team possible using the best staff and processes each organisation had to offer while providing an equitable share of revenue, profit and risk. It was thus decided to form a fully integrated Joint Venture with the team structured to achieve a mix of Aurecon and SKM staff throughout the different disciplines and at each technical and managerial level. Teams that were used to working with each other within their respective organisations were specifically broken up and mixed with those of the other organisation to break down company barriers and promote a feeling of belonging to the project team and not the parent organisation. This organisation structure was absolutely critical to the effectiveness of the Joint Venture.
Design management challenges
The design of a road project as large as Peninsula Link was as much a logistical challenge as a technical one. This included developing in excess of 5 000 construction drawings within a 12 month programme and to exacting quality standards. The project was broken down into design packages consisting of, for example, individual bridges, side roads, five kilometre sections of freeway and sections of drainage design. In total there were approximately 110 packages. The design team was split into delivery teams focussing on approximately seven design packages each. With the design progressing on multiple fronts simultaneously, one of the biggest challenges was ensuring that changes to one package were communicated to other teams impacted by this change. This created a significant time commitment resulting in discipline leaders spending as much time reviewing other disciplines’ work as their own.
Although the majority of the design was delivered by the Aurecon and SKM Joint Venture, other consultants were engaged to provide specialist input including geotechnical (Golder Associates), urban design (ARM), landscape (Urbis and Phil Liston and Associates), traffic signals, signs and linemarking (CPG), road safety audits (Traffix) and proof engineering (SMEC). Coordinating the input of these other consultants was critical in achieving the multiple deadlines. This was achieved by programming every required input and delivering a four-week look ahead of required inputs to all consultants on a weekly basis.
In developing the design, a multitude of reviewers and stakeholders were required to either approve or provide input into the design process. This involved six design review gates for each package prior to being issued for construction. There were over a dozen key stakeholders, reviewers and approvers involved in this process including the Independent Reviewer, LMA, VicRoads, the Proof Engineer, Abigroup, Conneq (now Lend Lease Infrastructure Services), the Operation and Maintenance Safety Auditor, Road Safety Auditor, three Councils, the water authority, several utility companies and bicycle groups. Achieving their sometimes conflicting requirements was a major challenge and this was achieved through a combined effort between Abigroup and the Joint Venture.
The relatively short design programme and extensive review and approval process meant that during the peak period, the majority of design packages were being developed concurrently. Even with the combined resources of two major consultants it was a major challenge to provide the number of resources required to meet the delivery targets, with the design team peaking at well over 100 staff. To meet this challenge, the design and documentation of six bridges was carried out off-shore by Aurecon’s Tshwane and SKM’s Kuala Lumpar offices. In addition, design verification was provided by several design offices around Australia, New Zealand, Hong Kong and South Africa and other specialist input or resources were provided from almost all the other major Australian offices. In this respect it was a truly global effort.
Urban and landscape design
A distinctive feature of Peninsula Link is its high quality urban and landscape design. The design for Peninsula Link combines landscape, architectural elements and public art with an aim to provide a memorable environment for motorists, residents and visitors.
The use of colour and design on the freeway represents the journey from the north to the south in which the motorist moves from an urban and culturally-rich setting into the rolling, green landscape of the Moorooduc Plains.
The contemporary design is sensitive to the local surrounds with:
Peninsula Link has come to life with the planting of more than 1.5 million trees, shrubs and grasses as part of its landscaping program. This linear parkland is also being supported by new rain gardens and wetlands, which were created to treat excess water from the roadway.
Newcomers to Melbourne will notice that several of the freeways within the metropolitan area incorporate major sculpture pieces within the road corridor to provide interest for road users. In keeping with this theme, Southern Way capitalised on the fact that Peninsula Link passes within a few hundred metres of the southern hemisphere’s largest sculpture park, the McClelland Gallery and Sculpture Park. A partnership was formed with McClelland to assist with the procurement of the new sculptures, the largest of which measures almost 17 metres high. The partnership created an opportunity to promote Frankston as a cultural hub while providing a talking point for motorists on their journey along the route.
'Panorama Station' will be permanently located at the Peninsula Link/EastLink interchange while 'Rex Australis' and the 'Tree of Life' will be the first two of fourteen sculptures installed temporarily at Skye Road and Cranbourne Road, with each sculpture being replaced every four years.
Art funding was wholly provided by the Southern Way consortium. Initial donations were provided by the two key sponsors at the time of the bid being Abigroup and Royal Bank of Scotland.
After each cycle of display on Peninsula Link, the temporary Southern Way McClelland commissions will become part of the McClelland Gallery and Sculpture Park’s permanent collection, providing a legacy for the local and wider cultural community. It is not often that a major road project can be used as such a promoter of art in this way.
Environmental focus – The Pines Flora and Fauna Reserve (the Pines)
Like all major road projects, there were a large number of environmental issues that required careful attention through the design and construction process. The most sensitive area was the Pines, a 220 hectare State Significant Bio-Site which effectively became bisected by the new road corridor. The reserve contains a number of national and state significant flora species and traces have been found of the endangered Southern Brown Bandicoot. Other significant species present in the reserve include the Dwarf Galaxia fish, swamp skink and other marsupials including possums and wallabies.
Tamarisk Creek and its associated flood plain passes through the reserve and crosses the road corridor in three places. This waterway forms a vital role in providing habitat within the creek and at its banks and also supports native vegetation through regular inundation of the surrounding land during storm events. The path of the creek alternates between sections of defined channel and sections of sheet flow. The creek was realigned in the vicinity of the freeway and extensive flood modelling was undertaken to ensure that flow regimes were maintained to support the wider vegetation needs.
In order to simultaneously address the fauna connectivity issue and allow for the hydrological regime to be maintained, the alignment of the freeway was raised above ground throughout the length of the reserve. Also included in the design was an extensive fauna underpass, three creek bridges, drainage culverts, three fauna crossings (complete with animal “furniture”) and a fire service access bridge beneath the freeway. In order to reduce the extensive native vegetation that would have been impacted by fill batters, the majority of Peninsula Link within the Pines was retained within vertical reinforced soil walls. Above these, light spill walls were incorporated to prevent both light and excessive noise from filtering into the reserve and startling fauna. To prevent motorists experiencing a ‘canyon effect’, the light spills wall design incorporated variations in pitch, offset from the road and in colour and material.
Transport sustainability – providing for future transport needs
One of the performance criteria set by LMA was to provide for a future heavy rail corridor within the median over approximately half the length of the project to be constructed at a later date. The provision of future rail results from EastLink and Peninsula Link corridors being targeted as one of the options to provide increased access to the nearby Port of Hastings, which is set for major expansion in coming years.
This criterion impacted on all the design disciplines to a much greater extent than was first envisaged. The median was required to be widened to accommodate twin tracks, overhead gantries, signals, access tracks, and concrete separation barriers. The median also needed to be wide enough to facilitate bridge piers and protection barriers and account for the differing horizontal requirements such as the use of spirals on horizontal curves. In addition, the grade constraints on the rail alignment and the headroom requirements at over-bridge locations were more onerous for the rail alignment than for the freeway. To address these issues, a unique horizontal and vertical alignment was developed for the rail tracks and this was used as an input into the design process. Factors that needed to be considered in addition to the median width included:
Ground conditions and weather impacts
One of the biggest challenges facing Abigroup was the demanding ground and weather conditions during the construction of Peninsula Link. Significant portions of the Peninsula Link corridor are historically soft and wet areas, with the Indigenous Australian translation of ‘Moorooduc’ being ‘flat and swampy’.
Efforts to manage the soft ground conditions were hampered by two years of above average rainfall, including the wettest summer on record in 2010/2011.
To overcome some of the constraints posed by the soft ground conditions, Abigroup implemented innovative engineering techniques. This was particularly evident at the EastLink interchange, where the project’s largest bridge and interchange are located on swampy grassland. The initial design for the Eastlink interchange contemplated placing thousands of concrete piles into the underlying soft ground with the bulk fill then constructed on top using a traditional retaining wall structure.
Abigroup, through its consultants, SMEC, introduced a construction technique that was a first for Australia. The retaining wall was constructed in two stages using a false face to allow the bulk fill to settle and flex as required. This reduced the amount of piles required to 350 saving a significant amount of time and resources, as well as providing numerous environmental benefits for the area. Once the expected 700 millimetres of settlement was achieved, the road surface could be constructed on top and the architectural cladding attached to the face of the wall.
Innovation in noise wall design and installation
Another Australian first implemented by Abigroup was the use of Rotational Moulded Panels (RMP) to construct the freeway’s noise walls in lieu of traditional precast concrete panel walls. The RMP noise walls have delivered substantial benefits to the project and to residents living along the freeway corridor. The panels are made from Low Linear density polyethylene in fine powder form which is manufactured into a panel by rotational moulding, a production method that has a lower carbon footprint than concrete equivalents.
The RMP noise walls have the same noise attenuating properties as other types of noise walls but have far greater design flexibility than equivalents, which allows architectural patterns to be displayed on both sides of the walls. The ‘text’ design panels in use on the project have 37 patterns on the front and seven on the back while the ‘geology’ design has eight patterns on the front and back. The non-porous nature of the panels makes them far more resistant to graffiti and easier to maintain.
Another significant benefit in using the new material is the substantial weight reduction of a hollow plastic panel in comparison to a concrete equivalent. This has generated significant flexibility and time savings during installation which all adds up when considering that 4 600 panels have been installed as part of the project.
Peninsula Link was a long time coming in many respects, with the Frankston and Mornington Peninsula communities anticipating the project since it first appeared in plans in the late 1960s. Although there were challenges along the way, Abigroup successfully opened the freeway on 18 January 2013. Peninsula Link has provided a new benchmark for elements such as its delivery model, design considerations and unique construction methods. Many of these innovations would not have been possible without the parties involved, and the collaborative relationships that were formed to deliver this important piece of infrastructure for the Victorian community.
This article was first published in ICE Civil Engineering Journal.