Nepean River Bridge
The NSW Government is planning to build a new pedestrian and cyclist bridge spanning the Nepean River between Penrith and Emu Plains.
Updates and announcements
The NSW Government is building a new pedestrian and cyclist bridge over the Nepean River to connect Penrith and Emu Plains. The new bridge will provide a safe crossing for pedestrians and cyclists over the Nepean River and improve connections to existing and future shared paths, including the Great River Walk.
The project was approved in November 2014, and in December 2014 Roads and Maritime Services started early site preparation work which involved the demolition of the remaining derelict building on the Log Cabin site at Memorial Avenue, Penrith.
Over the past 15 months, we have carried out the detailed design of the bridge and invited construction tenders to build the bridge. Roads and Maritime has contracted Seymour Whyte Constructions Pty Ltd to build the bridge.
Construction work to build the bridge is due to start in mid-late 2016 and is expected to take about two years to complete, weather permitting.
Changes during detailed design of the bridge
A curved design was considered during the concept design and environmental assessment phase of the project. During the detailed design phase of the project, the design of the bridge has been revised and now incorporates a straight triangular truss with a gentle vertical curve. The straight truss bridge option will still provide a large span, generous width and unique structure that will be an attractive landmark for the area.
The straight option significantly reduces the cost and will provide:
- A more efficient structural design which reduces the amount of steel needed by 20 per cent
- Less complex fabrication with less welding and more similar pieces of steel
- A simplified construction methodology because it will reduce bridge self-weight loads
- A reduction in risks during the construction of the bridge
- Environmental benefits by reducing the energy required to build the structure as a smaller amount of steel would be needed and this in turn reduces the carbon footprint.
The estimated cost of the bridge design was originally prepared in 2012 at strategic stage and was based on a preliminary concept design. As the design was developed the complexity of the project became better understood, and the estimated cost of the bridge is now $49 million.
The key factors that contributed significantly to a higher than previous cost estimate were the complex nature of the long span structure and associated construction methodology, as well as the relocation of overhead high voltage electrical lines crossing the river. The new straight truss bridge option has helped to keep the overall cost down.
Community members campaigned for a safer crossing over the Nepean River for pedestrians and cyclists as the current path on Victoria Bridge has no barrier between the narrow footpath and road traffic. During the strategic stage and concept development, a clip on shared path as well as a stand-alone pedestrian and cyclist bridge directly next to Victoria Bridge on the southern side were investigated. A structural feasibility study was completed in 2010, which determined the Victoria Bridge would not have sufficient structural capacity to accommodate a clip on shared path structure. An adjoining bridge next to Victoria Bridge would adversely affect flooding and impact on the heritage structure.
The final location of the bridge was pushed further south away from Victoria Bridge to avoid hazards and other local constraints. These included heritage, access to and around property and the submarine high pressure gas mains on the southern side of the bridge which supplies Blue Mountains residents with gas.
In mid-2012 a number of community information sessions were held to assess the best location for a new crossing of the river. Six crossing locations were ranked against key criteria identified during the community consultation workshops including safety, function, cost and community.
The location south of Victoria Bridge was considered the most safe and appropriate. The preferred bridge design and location was chosen following extensive community consultation, as it best addressed environmental, engineering and community constraints.