Large scale model constructed to test the stability of Scrivener Dam

Scrivener Dam is a critical piece of Canberra’s infrastructure, maintaining water levels of the iconic Lake Burley Griffin.  Like all dams in Australia, it requires regular maintenance and assessment to ensure ongoing safe operation. 

A recent inspection identified potential for undesirable uplift forces under the stilling basin slab, triggering a more detailed assessment of dam stability. UNSW’s Water Research Laboratory (WRL) was commissioned by the National Capital Authority to construct and test a 1:40 scale physical model at the Manly Vale campus. 

Despite advances in numerical modelling, physical modelling remains the most trusted method for determining complex the hydraulic behaviours found on dams, particularly in the energy dissipation basins.  Modelling provides critical data on flow behaviours, pressures and forces that impact the dam structure, and allows engineers to design the structure appropriately.

Dam models generally need to be constructed at large scales to minimise scale effects.  WRL’s purpose built hydraulic facilities were ideal for the model which measured 25 x 9 metres, with large pumps delivering over 1,000 litres of water per second to the model. It was also crucial that it was constructed to a high level of accuracy, and WRL’s specialist engineers and craftsmen were able to ensure accuracy of less than one millimetre across the dam structure.  

The results of the modelling will be used as part of the overall risk assessment for Scrivener Dam to ensure its ongoing safe operation.

Top image: Scrivener Dam photographed near the National Zoo & Aquarium in Yarralumla, Australian Capital Territory. Credit: Bidgee, via Wikimedia Commons, licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license.