This page gives a brief history of the Airlie Road overbridge in Plimmerton where the road crosses the Main Trunk Railway near Whenua Tapu Cemetery, in the north of Porirua City.
Locals knew the Airlie Road overbridge near Plimmerton as the "Black Bridge", arising from a legend that the bridge was sufficiently low to decapitate incautious trainmen. The bridge would have been built to normal railway standards and there is no evidence that anyone was ever decapitated on it or other similar bridges. However it is an interesting community legend and it would be interesting to find out how it arose.
This bridge appears to have been built in 1937, replacing an earlier timber bridge that was built in 1912. The bridge is a late example of a timber Howe truss bridge; after the 1930s concrete and steel structures replaced timber structures for railway work.
Few examples of these bridges remain today. The majority of these bridges are owned by Ontrack and are part of the national rail system and most are located in the South Island. The most dramatic example in New Zealand was the (recently demolished) "S"-shaped No.1 Rapahoe Bridge at Greymouth which had 10 spans in timber Howe trusses running across the Grey River. While no comparative research has been carried out to establish definitive numbers, there are few known examples of timber Howe truss road bridges remaining in New Zealand - the four bridges on the Akatawara Road are the only ones surviving in the Wellington region - and the Airlie Road Bridge was the only one known to be associated with a railway.
The bridge is an interesting historic on Airlie Road, which is itself an important historical route in the area.
This bridge has now been replaced with a modern concrete structure.
See also the Airlie Road Bridge page under the Porirua's Rail Heritage section.
Built By Optimation