This list documents historical bridges located in New South Wales, Australia. Road, rail and pedestrian bridges are listed. Generally bridges built before WWII (1939) have been included in this list.
Bridge construction in New South Wales starts with the needs of the first settlers and continues through to the present day with advanced bridge design. The infant colony had limited expertise and limited materials, as time passed techniques and materials were developed that allowed greater spans to be crossed and therefore expansion of the colony into otherwise inaccessible areas.
The NSW Public Works Department was under pressure from a cash strapped government to produce as much road and bridge work for as little cost as possible. The cheapest bridge was the timber truss which could be built with local timber.
All bridges are unique, in the end the bridge that is built depends on the technology, expertise, materials and need to gain access to an area.
At the time of early settlement (1788 onwards) NSW was very isolated from the technological advances being developed in Europe and North America. Materials such as cast iron were unavailable to early colonial NSW bridge builders. NSW bridge builders had to rely on their own resourcefulness, bred of isolation, distance and the unique environment.
New South Wales's unusual environment results in unusual, and extreme river flows, almost no flow for most of the year, some flow each year and extreme floods around once a decade. Inland the cause is the low pressure system coming over the continent, due to a large high pressure of the Indian Ocean. This often occurs at summer, at which time it causes cyclone season, although it can occur at any time of year (but not inducing cyclones). At the coast, the cause is the "east coast low", which occurs at similar places at the eastern edge of a number continents, and sees the continent's normal high pressure systems becomes one large and stationary system, perhaps due to doldrums over the west coast's ocean, at which time the global trade winds deviate, inducing the low pressures at polar and tropical latitudes to connect along the east coast, producing a trough situation that mimics the tropical monsoon. An east coast low rain event can occur at any time of the year. Early settlers often replaced washed out bridges with a similarly rudimentary structure, only to see it also washed away in a heavy rain event. The government came to see that this was a major problem holding back economic development in New South Wales.