SA Water dam portfolio risk assessment
Client: SA Water
Location: South Australia, Australia
Date: March 2013 – June 2014
Assessing the risks of a portfolio of dams to better prioritise safety works.
SA Water owns and manages 18 large dams of varying types, sizes and ages. To inform and prioritise its dam safety improvement program over a 10-year planning horizon, SA Water required an update of its original portfolio risk assessment completed in 1998.
Entura began the portfolio risk assessment with a detailed review of background information on the dams, including hydrological, geotechnical, structural and consequence assessment. Through a carefully planned process of inspection, workshops and analysis, each dam was assessed to identify failure modes and their probability and consequences, to estimate and evaluate risks, and to develop a prioritised program of further investigations and measures to reduce risks across the whole portfolio.
Entura's experience in conducting dam risk assessments and dam portfolio risk assessments for a range of dam owners enabled us to address the wide range of dam types and ages to give an efficient and consistent output across the portfolio, and to tailor the dam safety improvement program to the specific needs of SA Water.
The key output of the portfolio risk assessment was an updated and prioritised dam safety improvement program. Entura developed a summary spreadsheet for the dam safety improvement plan that was simple to use and update and focused on key risks. This ‘live’ document ensured that the plan could respond to new information that might change the risks for a particular dam and could adjust the priority of risk reduction measures.
The portfolio risk assessment led to a number of further studies and works to reduce the overall dam safety risks. The dam safety improvement program has assisted the dam safety team at SA Water to provide strong justification for their proposed capital works program and to reduce uncertainties through appropriate investigations.