Construction began on Hobart's Floating Bridge in April 1938 and the bridge opened for traffic in December 1943. After 21 years of service, the two lane floating bridge was removed and little evidence of this innovative structure remains.
Photograph: Libraries Tasmania, Tasmanian Archives
The floating portion consisted of 24 reinforced concrete pontoons, joined in two groups of 12 to form two half arches, each 480m long. Hinged on/off ramps connected the roadway to the pontoons which rose and fell with the tide.
Plans for a replacement bridge began around 1955. Its replacement, the four lane Tasman Bridge immediately downstream, was opened in August 1964. A day later the floating bridge was separated into its two halves. After years of discussion about whether further use could be made of the pontoons, one sixth was towed to Bruny Island to be a jetty at Alonnah and most of the remainder was sunk in deep water in Storm Bay.
Reference: Hobart's Floating Bridge, Nomination for a Heritage Recognition Award, engineersaustralia.org.au
Photograph: Libraries Tasmania, Tasmanian Archives
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