Pyrmont Bridge is one of the world's oldest surviving electrically operated swingspan bridges. The first bridge began operating in 1857 and the current swingspan bridge opened in 1902. The bridge provided the main transport route between the city and Sydney's growing western suburbs while the swingspan allowed tall vessels to access Darling Harbour.
The bridge is a key piece of engineering heritage and the swingspan has opened more than 600,000 times in its lifetime. An Institution of Engineers Australia commemorative plaque is at the bridge's west end and an inscription in the stonework at the eastern end recognises Percy Allan.
Facts and figures
Length: 369 metres
The bridge cost £112,500 to build
The bridge is made up of 14 spans
Australian ironbark timber is used on 12 spans, while the two central spans, which swing, are constructed from steel
The swingspan weighs 1,000 tonnes and is supported on a base made from concrete and local sandstone. The base is filled with mass concrete and weighs 6,800 tonnes. It is 13 metres in diameter and 19 metres deep. The water is 6.5 metres deep and the base extends a further 10 metres below the sea floor
Pyrmont Bridge takes approximately 60 seconds to open completely to 83 degrees. It has to be opened for vessels more than 7 metres high
Vessels/barges up to 21.5 metres wide can pass through the channel once the Pyrmont Bridge has been opened
Pyrmont Bridge is driven by the original two 50 Hp 600 volt DC General Electric type 57 electric motors. Manual drum-type General Electric tramway controllers are used to drive the motors for the swingspan and gates
Power to operate the bridge was originally drawn from Ultimo Power House (now the Powerhouse Museum)
