The Lachlan River railway bridge is a heritage-listed former railway bridge which carried the Blayney–Demondrille railway line over the Lachlan River at Cowra, Cowra Shire, New South Wales, Australia. It was designed by John Whitton in his capacity as Engineer-in-Chief for Railways. The bridge was built from 1886 to 1887 by contractors Fishburn & Co. It is also known as the Cowra Rail Bridge over Lachlan River and the Cowra Lattice Railway Bridge. 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.
History
Tenders for the section of line including the bridge were advertised in February 1885. The bridge was completed in sixteen months, with no accidents even though it was at the time the highest bridge in New South Wales. A temporary bridge to facilitate access for contractors and machinery had to be erected, and work proceeded even though the river was in partial flood at several times during works. The official opening of the Young-Cowra section of line took place on 25 August 1886; however, trains could only proceed as far as the river, as the bridge works were not complete. The last rivet was placed in June 1877, and the bridge was opened to passengers for the first time on 9 September 1877.
Description
The Cowra Rail Bridge over the Lachlan River is a three-span continuous iron lattice bridge. The spans are to centres of piers and the lattice work has four triangulations. The piers are pairs of cast iron cylinders (supplied by Stockton Forge Co, England). The bridge has wrought iron plate web girders at each end of the lattice bridge.
Apart from relatively minor technical works of repair and strengthening, the bridge retains its original fabric.
Significance
During the 20-year period 1873-1893 there was a massive program of public works in New South Wales, particularly in expanding the road and rail networks. It was a boom period that ended with a severe economic depression.
Despite the boom conditions, the respective Chief Engineers, for Roads (William C. Bennett) and for Railways (John Whitton) were constrained to economise by using as much local material as possible, consequently an enormous amount of hardwood timber was used for bridge works, mostly timber beam and timber truss bridges. However, there were many major rivers to be crossed, requiring long span bridges, for which no form of timber bridge was suitable. These large bridges had to be metal and supplied from England, a very expensive import cost to the successive colonial governments.
Both Chief Engineers were British so they chose the widely used wrought iron lattice truss bridge in the half-through form. Twelve of these were built for the railways and 24 for roads. These two sets of iron lattice bridges are the most significant group of bridges of the colonial period. A high percentage are extant and still in use, 11 on railways and 18 on roads.
The current railway lattice bridges are:
1876Bathurst Rail Bridge over Macquarie River - still standing but no longer in use 1881Macquarie River at Wellington 1882Peel River at Tamworth 1882MacDonald River at Woolbrook 1884Rail Bridge over Murray River, Albury-Wodonga 1884Macquarie River Railway Bridge, Dubbo 1885Murrumbidgee River at Narrandera 1887Lachlan River at Cowra.
Two former railway lattice bridges (1885 Georges River at Como and the 1886 Meadowbank Rail Bridge over Parramatta River) were converted for use by pedestrian/cycle ways.
The 1871 lattice railway bridge over the Hunter River at Aberdeen was replaced by steel girders and demolished. The 1881 Murrumbidgee River at Wagga Wagga was demolished in 2004 and replaced with a concrete structure.
Heritage listing
Cowra was reached by rail in 1886, the line extending from Young. The bridge built in 1886 is one of the original iron lattice Whitton bridges and is an important surviving element from the most significant period of railway development. It is an excellent example in an important railway town. The building of such a relatively large structure on this cross country line reflects the importance that the railway administration gave to this line to provide an outlet for coal from Lithgow, and produce from central NSW, to reach the south and Victoria and vice versa.