Tharwa Bridge restoration

Tharwa Bridge over the Murrumbidgee River, located in the ACT, is the oldest and largest surviving four span timber Allan truss bridge in NSW/ACT, constructed in 1895. The original design was by Australian engineer Percy Allan. This structure is considered to be of exceptional national heritage significance for the ACT, and continues to provide a safe means of thoroughfare when the Murrumbidgee River levels rise during flood. For its national heritage value the restoration of the old bridge was undertaken, keeping as close as possible to the original design, rather than providing an alternative bridge using modern materials such as concrete or steel. This project showcases several innovations in timber truss bridge design which address the limitations typically encountered in truss arrangements, as well as applying modern techniques in timber construction, providing a more sustainable use of timber through increased durability and adaptive engineering.