Yass Town Rail Bridge

The Yass Town railway truss is highly significant because it was the major component of infrastructure on the historic (infamous) Yass Tramway. It is a highly visible and imposing structure and it set the course for the adoption of American bridge technology in lieu of the previous dominance of British bridges so favoured by John Whitton. Despite being abandoned, it still retains its original fabric. It is a landmark structure in the history of railway bridges in New South Wales.

Yass Rail Bridge
by John Immig (2005)

Historical Notes: When the extension of the Main South Railway from Goulburn to Cootamundra was being planned in 1870 it was intended to take the line into Yass Town. However, following a site visit by Engineer-in-Chief John Whitton who recognised the route would involve more than one crossing of the Yass River by expensive iron bridges, the line was shifted 5 kms (3 miles) north which required no crossings of the river but bypassed the town. Despite the vehement protests of the townsfolk, the Departmental route was adopted and the line was completed to Bowning (north west of Yass) in July 1876 with a station about 3 km (2 miles) north of Yass Town.

So, although the Yass residents could not have the main line through their town, they persistently petitioned successive governments to have a branch line and were eventually successful. In 1889 the Minister for Public Works authorised construction of a lightweight railway or tramway from the renamed main line station, Yass Junction to the town. It could have stopped at the Yass River with passengers and goods transhipped the short distance into town via the existing iron lattice road bridge. But no, the tramway had to go into the town, so a large (200 feet) span steel truss was built over the river.

The bridge represented a gross over capitalisation of a line that would prove to be operationally expensive and never showed a profit. Contractors Kerr & Cronin completed the line in July 1891 for £13,156 and McMasters’ bridge cost £5,412 in an all up cost of £27,318. So the bridge represented 20% of the final cost, just to satisfy town ego and have a grand opening ceremony in the town by the Governor, Earl of Jersey, on 20th April 1892.

Detail of the Yass Rail Bridge
photo by John Immig (2005)

Despite the Railway’s displeasure with the line, the bridge was in fact a technical milestone. Prior to this, the dominant main line metal bridge was the heavy wrought iron lattice truss, fully imported from England. But on the eve of John Whitton’s retirement, the winds of change were blowing. The technical and economic merits of American bridges was widely recognised and independent groups of engineers in the Railway Construction Branch under Henry Deane, the Existing Lines Branch under George Cowdery and those in the Tramway Branch were designing and planning to construct large American steel trusses and Yass got the first.

Physical Description: A single span, lightweight steel Pratt truss of 61m (200ft) span on brick piers with timber beam approaches.

Source: NSW Office of Environment & Heritage, Heritage Branch Website online database at www.heritage.nsw.gov.au/07_subnav_01_2.cfm?itemid=5012296.

Photos: Yass Rail Bridge – views by John Immig 2005

Did anyone in your family work on construction of the Yass Town railway? Please share their memories.