The Tasman Bridge is a five-lane bridge crossing the Derwent River, near the CBD of Hobart, Tasmania. Construction started on the bridge in 1960. It was completed and opened to traffic on 17th August, 1964 as a four lane bridge. It replaced the earlier pontoon Hobart Bridge.
The bridge has a total length (including approaches) of 1395m - longer than the Sydney Harbour Bridge. It provides the main traffic route from the CBD (on the western shore) to the eastern shore - particularly the airport and Bellerive Oval. It has a pedestrian footway on each side, but no dedicated lane for bicycles. However, steps to the pedestrian footway have recently been replaced with on-ramps.
On the 5 January 1975, the Tasman Bridge was struck by the bulk ore carrier Lake Illawarra, causing two pylons and 127 metres of concrete decking to fall from the bridge and sink the ship. Seven of the ship's crewmen were killed, and five motorists died when four cars drove over the collapsed sections before the traffic was stopped. The depth of the river at this point (35 metres) is such that the wreck of Lake Illawarra lies on the bottom, with concrete slab on top of it, without presenting a navigation hazard to smaller vessels.
The breakage of an important arterial link isolated the residents in Hobart’s eastern suburbs – the relatively short drive across the Tasman Bridge to the city suddenly became a 50 kilometre journey around the bay. Although ferries provided a service across the Derwent River, it was not until December 1975 that a single lane Bailey bridge was opened to traffic, thereby restoring some connectivity.
Large vessels passing beneath the bridge must now do so slightly to the west of the original main navigation span. Personnel controlling ships (or harbour pilots) must be trained and then cleared for using the special laser lighthouse that indicates by colours whether the ship must be steered left or right to regain the centre line.