Tasman Bridge Stastics

Tasman Bridge Stastics

River Bed

The nature of the strata underlying the river bed is shown on the above geological cross section. It will be seen that the major part of the bridge is founded on either basalt or dolerite at depths up to 160 feet below water level. Beneath Piers 4 to 8, the dolerite is as much as 300 feet below water surface and is overlayed by very stiff clays, a thin layer of coarse gravel and shingle, very stiff sandy loam and conglomerate.


Overall length including approaches 4,650 feet.

Waterway width 3,500 feet.

Main Viaduct spans (19) 140 feet.


Overall width 57'-2".

Width of roadway 44 ft. consisting of four 11 ft lanes, since the rebuild, five lanes 3.350 meters wide.

Width of footways 4 ft each.

Main Viaduct Deck

Supported by six concrete beams 140 ft in length and weighing approximately 90 tons each.

Main Viaduct Columns

Each column is 10 ft wide and 2' 6" thick. Each of the columns adjacent to the main navigation channel is 10 ft. wide and 12 ft. thick, and next to these at limits of secondary navigation spans are columns 10 ft. wide and 8 ft. thick.

River Crossing

3,364 ft. consisting of two navigation flanking spans of 197 ft. and nineteen spans of 140 ft. which 13 lie to the west of the navigation spans and 6 to the east.

Approach Spans

Western bank - 435 ft.

Eastern bank - 850 ft.


The underside of the central navigation span is more that 150 feet above mean water level.

Navigation Spans

310 feet overall and 240 feet clear span, anchor spans (2) 197 feet.


Maximum gradient 1 in 18.

Piles (Under Water)

216 piles made of 54" diameter steel tubing.

Deepest pile 265 feet below M.W.L.


There is a 4ft. 6 ins. footway on each side on the roadway; beneath each footway, are 15 inch diameter water mains, electricity supply and Telstra cables.

Quantities of Materials

Cement - 8,000 tons.

Steel tubing for piles - 33,000 ft., 54 in. in diameter.

Total quantity of concrete - 80,000 cubic yards.

Tons of reinforcing steel - 5,200.

Total length of prestressing cables - 72.5 miles.

Sand - 20,000 cubic yards.

Cost of Works

he total cost of the new Tasman Bridge together with approach roads and Lindisfarne interchange was in the order of 7,000,000.00 pounds. Construction commenced about May, 1960 and the bridge was first opened to traffic (2 lanes only) on 18th August, 1964. The bridge was completed with all four lanes operational on 23rd December 1964. During peak construction a labour force of over 400 men was employed on site.


Construction Authority - Public Works Department of Tasmania.

Consulting Engineers, G. Maunsell and Partners, London, England.

Contractor, Reed, Braithwaite, Stuart and Lipscombe, Salisbury, England.

Official Date of Commencement of Bridge Contract, 31 January, 1960.

Construction Commenced, April 1960.

First ship to pass under bridge, Galway, 18th August 1964.

Four lanes opened to traffic, 23rd December, 1964.

Official opening planned for 2.20 pm on Thursday, 18th March, 1965 by H.R.H the Duke of Gloucester.

Designed traffic capacity, approximately 34,000 vehicles per day.

Tasman Bridge Disaster

On the evening of Sunday, 5th January, 1975 at 9.27 pm, the bulk ore carrier "SS Lake Illawarra" loaded with zinc concentrate, collided with the Tasman Bridge. Two piers collapsed along with 127 meters of decking. Four cars ran over the gap into the Derwent, five occupants died, while several others managed to escape from their vehicles which were hanging on the edge of the gap. Seven crewmen from the "SS Lake Illawarra" also lost their lives

Tasman Bridge Repair

Immediately after the Bridge collapsed, the Federal and State Governments set up the Joint Tasman Bridge Restoration Commission to direct the reconstruction of the Bridge. Specialists in the marine engineering field undertook an extensive investigation to locate bridge debris. This survey took a number of months to complete, and parts of the bridge weighing up to 500 tons were located to an accuracy of a few inches, using equipment developed by the University of Tasmania and the Public Works Department.

Maunsell and Partners were appointed consultants for the rebuilding project. John Holland Contractors were awarded the contract. The Federal Government funded the project which began in October 1975. The Tasman Bridge was initially designed to carry four lanes of traffic, however prior to the disaster, heavy demands had been placed on the bridge during peak times. It was decided to widen the bridge as part of the reconstruction works to carry five lanes of traffic.

The Tasman Bridge took about two years to re-build at a cost of approximately $ 44 million. The Tasman Bridge was officially re-opened to the public on Saturday 8 October, 1977.

Tasman Bridge Stastics