NZ Visual Diary - entry 161
Viaduct Bascule Bridge
Installed in 1932, the Viaduct Bascule Bridge is one of the few bridges of its type in the world and was fabricated by the Cleveland Bridge and Engineering Co Ltd, Darlington, England.
It is a steel bascule rolling truss bridge. The Auckland Harbour Board installed it to span the 13.7m between the Eastern and Western Viaducts. It originally carried a railway connected to oil loading facilities on Wynyard Wharf and was raised and lowered at the arrival and departure of the fishing fleet.
It was manually operated and raised by rolling back 90° on its cam ends under counterweight. A pinion moved along a horizontal rack at the height of the centre of the cam-end circle. Later driven by electricity, it was in use until the development of the Maritime Museum on Hobson Wharf in 1992.
Now it’s used as a thoroughfare between Wynyard Quarter and the city centre and has been preserved for its engineering heritage value. 1
from the Eke Panuku website
< https://www.ekepanuku.co.nz/wynyard-quarter/viaduct-bascule-bridge-repairs >