Port River Expressway (PRExy) - Stage 1
Stage 1 of the Port River Expressway
- Stage 1 of the Port River Expressway consists of a 5.5 kilometre four-lane expressway link between Francis Street and South Road with overpasses at each of the junctions of South Road , Hanson Road and Eastern Parade. It also included the construction of Hanson Road (to Cormack Road) from the expressway to south of Cormack Road, providing an alternative access to the expressway from the south.
- Stage 1 was opened to traffic on 19 July 2005, with works commencing in December 2002.
- Funding for the project was a joint contribution between state and federal governments under the Roads of National Importance Program (RONI).
- The four-lane expressway was delivered through a Design-Construct-Maintain (DCM) contract by South Australian company Bardavcol Pty Ltd
- Traffic volumes along South Road between Grand Junction Road and the expressway have also decreased significantly, by around 9 000 vehicles a day. This represents a reduction in traffic of approximately 25% along this section of the corridor.
- Since its opening, Stage 1 of the Port River Expressway project has created a major shift in traffic flows from neighbouring arterial road networks. There has been a dramatic decrease in traffic volumes along sections of previously congested neighbouring corridors. Volumes on Grand Junction Road (immediately west of South Road) and Cormack Road have decreased by approximately 9 000 and 5 000 vehicles per day respectively.
View of Stage 1 of the Port River Expressway from the South Road overpass, looking east
Stage 1 included the construction of three overpasses at each of the junctions of South Road, Hanson Road and Eastern Parade.
South Road overpass
- The South Road overpass is a roadway loop connecting the expressway with Salisbury Highway and South Road through a portion of the existing Barker Inlet Wetlands.
- The need for an overpass at South Road, Wingfield became evident as a result of emerging developments in the South Australian economy, particularly in the north west sector. The forecasted increase in rail freight movements from 6-8 movements a day to a maximum of 30 movements a day in grain carting season presented the real prospect of traffic delays at the South Road, Wingfield level crossing, reflecting back to the junction with the expressway. The overpass will ease this tension between traffic and the increased use of the rail network.
- Improvements to the wetlands completed in early 2004, as part of the construction of the South Road overpass, have included the creation of deeper water holes to help prevent them from drying out and creation of islands for fauna and flora as well as an increase in the wetlands capacity to store and retain stormwater.
- Improvements to the wetlands are expected to enhance the attractiveness of the wetlands for bird life. It is thought that over thirty species of birds could potentially occupy or use the Barker Inlet Wetlands at some stage.
- To cater for bird life during the operation of the overpass, two drainage crossings large enough for swans were built under the embankment to allow passage to the central water basin (Keller's Hole) located in the roadway loop. Drains were also interlinked to the central water basin to provide access for bird life.
Hanson Road overpass
- The Hanson Road overpass provides a safe passage on and off the expressway and direct access to the proposed Wingfield Eco-Industrial Precinct, endorsed by the state government.
- Hanson Road has been upgraded to four lanes between the expressway and Cormack Road . The Hanson Road link provides a more efficient and quicker alternative route for heavy freight vehicles travelling between Adelaide's northern and southern suburbs.
Eastern Parade overpass
- The Eastern Parade overpass spans approximately 270 metres over Eastern Parade and the freight rail line to Port Flat Yard, where considerable delays for traffic were previously experienced due to trains queuing across level crossings.
- In a number of locations, reinforced earth retaining walls have been incorporated within the embankments of the overpass where retaining structures were required. 'Ashlar' precast concrete facing panels have been used and provide a rock type finish.
- The Eastern Parade overpass has urban design features such as bright blue steel beams and reinforced earth walls with a rock face appearance to create an industrial theme, characteristic of Port Adelaide.