Macleay River and Floodplain Bridge

Kempsey, Australia



Road Transport Authority, New South Wales

Main Contractor:



Foundation Contractor:


Bauer Foundations Australia

Scope of work:


Construction of 60 no. 1800mm and 4 no. 1050mm diameter bored piles

Construction Period:


October 2011 to June 2012


The 3.2km long Macleay River and Floodplain Bridge is a part of the 14.5km long Kempsey Bypass on the Pacific Highway halfway between Brisbane and Sydney. The part of the bridge over the Macleay River is subject to high flood levels and significant scour and is therefore founded on large diameter bored piles.


The river bed consists of approximately 15m of Holocene Estuarine deposits, which consist of silty sand and clayey silt. These overlay an old alluvium mainly comprising gravels and some cobbles. Siltstone bedrock commences at around 24m below the river bed level. The rock has an unconfined compressive strength ranging from 10 to 40MPa, increasing with depth.


The piling works were completed during two visits with an overall period of six months. During the break in piling works, the rock fill platform was moved from one side of the river to the other in order to ensure that the flow of the river was never interrupted.