Severn River railway bridge, Dundee Viaduct 1886 NSW there 4 viaducts around here 08 12 24

Описание: The Severn River railway bridge is a heritage-listed railway bridge that carries the Main Northern Line across the Severn River at Dundee, Glen Innes Severn, New South Wales, Australia. It was designed by John Whitton in his capacity as Engineer-in-Chief for Railways and built in 1886. It is also known as Severn River Railway Viaduct. 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.
Description
Located 701.98 kilometres (436.19 mi) from Central station, the Severn River bridge is a 13-span timber truss viaduct; each span is 12 metres (40 ft) centre-to-centre of timber trestles.

The trusses are deck Queen post copied from one of Brunel's Cornish timber bridges (St Germans), built about 30 years earlier
History
When John Whitton, Engineer-in-Chief for Railways 1856–1890, extended the Main North Railway from Muswellbrook to Glen Innes, 1870–1884 it climbed through the highest parts of the Great Dividing Range into the New England Region. Gradients were steep, curves were sharp, there was heavy earthworks and some major iron lattice bridges. It was expensive railway construction.

When the section from Glen Innes to Tenterfield was planned, economies were made, particularly with bridges. They had to be timber, mostly ballast top timber beam bridges but at three locations larger bridges were required, over the Beardy Waters, Severn River and Bluff River.

Whitton, a successful railway engineer from England, chose one of Isambard Kingdom Brunel's timber bridge viaducts built in Cornwall during the 1850s. The model chosen was the St Germans Viaduct, composed of composite deck Queen post trusses, with the bottom chords being large iron rods. Whitton's staff redesigned the trusses to be all timber and the viaducts were built during construction of the Glen Innes to Tenterfield section 1884–86.

The final section to Wallangarra (1888) was mostly easier over plateau country but the crossing of Tenterfield Creek required a large bridge and a timber Queen post truss viaduct was built there also, the fourth between Glen Innes and the Queensland border.

All four viaducts retain their original