Auckland harbour bridge opens

New Zealand’s best-known bridge opened after four years of construction.

The need for better transport links between Auckland city and the North Shore had long been the subject of inquiry and agitation. The Auckland Harbour Bridge Authority was set up in 1950 to raise funds and organise construction. The bridge’s ‘coat-hanger’ design, with lattice girders on the 243-m span, allowed ships to pass beneath.

Building the bridge involved clever cantilevering of the steel girders, and staff worked 33 m below sea level preparing the foundations of the reinforced concrete piers. The bridge is 1017 m long, and used 5670 tonnes of steel, 17,160 cubic m of concrete and 6800 litres of paint.

Originally, the bridge had four lanes, but this quickly proved inadequate. In September 1969 the ‘Nippon clip-ons’ – two lanes on each side, prefabricated in Japan – were added. At the time, this was pioneering technology, but 15 years later fatigue was discovered in the splice joints and several thousand had to be replaced. Tolls were charged on the bridge until 1984.