Historical Development of Arch Dams in Australia : From Advanced Designs to Engineering Failures

Since the early European settlements in Australia, the coastal and continental development of the country has been coupled with the availability of water supply. For two centuries, Australia's economy has been highly dependant upon its surface irrigation and, today, more than 85% of water diversions are for agricultural purposes (irrigation and stock watering only). During the 19th century, a series of arch dams was built. They included advanced technological features which were acknowledged world-wide. Advanced designs included the world's oldest concrete arch dam (75-Miles dam, 1880), the world's oldest thin concrete arch dam (Lithgow No. 1, 1896), a multiple arch dam (Junction Reefs, 1897) and a thin reinforced- concrete arch dam (de Burgh, 1908). Following these precursors, a significant number of arch dams was built all over Australia. Two series of arch dams were built by the NSW-Public Works Department (Irrigation and Water Supply) and by the NSW-Railway Department for town water and railway supply respectively. Some dams were also built in other States. Several of the dams are still in use today, highlighting a sound design. Some dams should be considered as engineering failures. The causes of failure included poor quality of construction material, reservoir siltation and improper planning. In the period 1880-1900, the Australian arch dam experience was renowned. But the same design technique was used for more than sixty years and the Australian arch dam expertise shifted from being most-advanced to outdated, with a number of reservoir failures and a lack of design technique progress