Long Cove Creek railway viaducts, Lewisham

About

The Long Cove Creek railway viaducts are heritage-listed railway viaducts which carry the Main Suburban railway line over Long Cove Creek between the suburbs of Lewisham and Summer Hill in Sydney, New South Wales, Australia. The viaducts were designed and built by the New South Wales Government Railways. The property is owned by Transport Asset Holding Entity, an agency of the Government of New South Wales. It was added to the New South Wales State Heritage Register on 2 April 1999.

The first section of railway built in New South Wales was opened as a single line from the Cleveland Paddocks (near Cleveland Street overbridge) to a site west of Granville on 26 September 1855. It was duplicated by June 1856.

The largest structure on the line was the 8-span stone arch viaduct over Long Cove Creek on the western side of Petersham. By the 1880s deterioration lead to its replacement by three pairs of 27-metre (90 ft) Whipple trusses, they were American type wrought iron, pin-jointed deck trusses. The bridge was only one of two bridges in NSW to employ the Whipple Truss (the other being a road bridge over the Shoalhaven River at Nowra ). These were subsequently replaced by welded, deck plate web girders in 1993. A pair of the Whipple trusses are on display on the southern side of the Lewisham Viaduct.

Two more tracks (quadruplication) were added in 1892 using three double track deck trusses of the British lattice type. These were also replaced by welded, deck plate web girders in 1998. Two further tracks were added for the sextuplication during 1925-27, on the northern side of the viaduct, for which three pairs of riveted steel, deck Warren trusses were erected. They are still in use.

The Lewisham viaducts trusses are located 0.25 kilometres (0.16 mi) west of Lewisham Station. The structure which comprises recently installed plate web girders and original Warren trusses carries local, suburban and main lines over Long Cove Creek. The original Whipple trusses which have been replaced by the plate web girders have been removed and displayed adjacent to the viaducts.

The viaducts include several structures:

- Girders: plate web girders on local lines (1993)

- Girders: plate web girders on suburban lines (1998)

- Trusses: Warren trusses on main lines (1926)

- Display Trusses: Whipple trusses displayed under viaduct (1886)

There are three pairs of double track, welded plate web girders which carry two local lines over Long Cove Creek. Each span of steel girders is 27.13 metres (89 ft) and are supported by brick piers and abutments.

There are three pairs of double track, welded plate web girders which carry two suburban lines over Long Cove Creek. The girders are made of steel and are supported on brick piers and abutments.

There are three pairs of single track deck Warren trusses which carry the main lines over Long Cove Creek. Each span is 27.13 metres (89 ft) and supported by brick piers and abutments.

A pair of original Whipple trusses has been retained on site. These are wrought-iron, pin-jointed deck trusses which were developed in America.

There are three pairs of double track, welded plate web girders which carry two local lines over Long Cove Creek. Each span of steel girders is 27.13 metres (89 ft) and are supported by brick piers and abutments.

There are three pairs of double track, welded plate web girders which carry two suburban lines over Long Cove Creek. The girders are made of steel and are supported on brick piers and abutments.

There are three pairs of single track deck Warren trusses which carry the main lines over Long Cove Creek. Each span is 27.13 metres (89 ft) and supported by brick piers and abutments.

A pair of original Whipple trusses has been retained on site. These are wrought-iron, pin-jointed deck trusses which were developed in America.

The Lewisham viaducts have moderate archaeological potential. Any evidence of the 1882 Lattice trusses on the suburban lines has been removed when replacement with plate web girders in 1998. However the pair of original 1886 Whipple trusses that have been retained on site and put on display under the viaduct, and provide evidence of the historic structures that were employed over the viaducts.

All girders and trusses were reported to be in good condition as at 1 September 2010.