Peats Ferry Bridge

The Peats Ferry Bridge, a steel truss bridge that spans the Hawkesbury River, is located northwest of the central business district of Sydney in New South Wales, Australia. The bridge carries part of the Pacific Highway from Hornsby to Kariong.

Peat's Ferry Road Bridge is of State significance owing to its historical associations and technical and engineering qualities. It was constructed between 1939 and 1945 and the current bridge fabric is original to the 1945 construction. The original parapets, however, have been partly removed and have had Armco barriers added over the truss span lengths. The bridge is at the site of the ferry crossing first established by George Peat in 1847. From 1945 until 1980s, when the Sydney to Newcastle Freeway was built, the current bridge provided a direct and vital link from Sydney to the industrial north.

— Statement of significance, Heritage and conservation register, Roads & Maritime Services, 15 August 2005.^[1]

History

The Peats Ferry, a ferry operated by George Peat from 1847 until the 1890s, linked two stretches of the Pacific Highway. The ferry service had been reinstated as a temporary measure in 1930 pending completion of the bridge, some forty years after the original Peats Ferry had ceased operation, made redundant by the completion of the Sydney-Newcastle railway in 1889. Prior to the construction of the bridge, the course of the Pacific Highway stretched from Kangaroo Point on the southern bank of the Hawkesbury River south to Hornsby and provided access to Sydney's northern suburbs and beyond. On the northern side of the Hawkesbury, from Mooney Mooney Point the Pacific Highway followed a mountainous route towards Mount White, Kariong, and then Gosford, on the route that is now the Central Coast Highway.^[5]

Description

The Peats Ferry Bridge was constructed between 1939 and 1945 and replaced the ferry service operated by George Peat.^[6][7] The bridge's construction predates the development of the Pacific Motorway. It was built as part of the Hornsby-Kariong section of the Pacific Highway, the first direct road link between Sydney and Newcastle. Before the bridge was built, road transport had to use a much longer route through Wisemans Ferry, or even further west. Construction of the bridge commenced in 1938 but it was not completed until May 1945.^[1]

The two main bridge spans are K-trusses of welded steel construction. Each truss span measures 440 feet (130 m) long and these were the longest welded truss spans in the world when built. The deck of the truss spans in concrete, cast in situ around the truss members. The truss spans were fabricated off site and floated into position on barges, requiring a high degree of accuracy and coordination in fabrication and bridge pier setting out. To the north of the truss spans, the bridge has eight long and eight short steel girder spans. The bridge deck to these spans is also cast in situ concrete but is believed not to act compositely with steel, as might be used in more modern construction.^[1]

Pier 2 supporting the main bridge spans is founded on a concrete caisson. The cutting foot of the caisson was cast on a barge in sheltered water and then floated out and sunk to the river bed within its own cofferdam. Jetting with compressed air and the addition of further sections of caisson then further sank the caisson. At one point the caisson accidentally slid under its own weight to below the water line. To recover this situation a further section had to be added by divers and the caisson pumped out, which is reputed to have taken a total of 9 months to recover. The final caisson extends 241 feet 4 inches (73.56 m) below low water level, just 8 inches (200 mm) short of the world record depth for a bridge foundation at that time, held by the San Francisco–Oakland Bay Bridge.^[1]

The bridge abutments are cast in situ concrete bearing to rock. Each abutment has concrete walls and parapets (balustrades).^[1]

The original railings to the east and west sides of the bridge spans were tubular top and bottom rails supported to steel angle standards with crimped wire mesh infill panels. These original rails still exist to the girder spans of the bridge. The rails to the two truss spans of the bridge were modified in 1966 by the removal of the tubular rails and crimped wire mesh and substitution with Armco type barriers bolted to the original steel angle standards. The bridge has two plaques at its south abutment commemorating the opening of the bridge in 1945 and the "energy and skill of its builders".^[1]

The bridge was superseded as the main crossing of the Hawkesbury River at this point by the opening of the adjacent six-lane Brooklyn Bridge as part of the fourth stage of the Pacific Motorway in 1973. It continues in service carrying the Pacific Highway route as a backup and alternative route to the freeway and provides access from the freeway to the town of Brooklyn and to Mount White.

See also

• List of bridges in Sydney

References

External links

• Kass, Terry (February 2006). "RTA Thematic History: A component of the RTA Heritage and Conservation Register" (PDF). NSW Roads & Maritime Services (PDF) (2nd ed.). Government of New South Wales. Retrieved 12 January 2015.