Moogerah Dam upgrade - Queensland
Client: Seqwater
Location: Queensland, Australia
Date: May 2012 – December 2014
Designing a cost-effective solution to upgrade a dam for greater stability and spillway capacity, to comply with flood safety requirements
Background
Moogerah Dam, approximately 60km west of Ipswich, Queensland, is a 40m-high, 219m-wide thin double-curvature concrete arch dam with an ungated spillway on the right abutment. It was constructed in the 1960s and, as the methods for flood estimation have advanced, it is now considered to have an inadequate spillway capacity.
Solution
Entura was engaged as the lead consultant to undertake the investigations and design of the Moogerah Dam upgrade, aiming to provide a staged upgrade of the dam to satisfy the latest flood capacity guidelines.
We undertook preliminary design of all stages of the preferred upgrade option and detailed design of the initial stages. This included three-dimensional finite element analysis (FEA) of the arch dam to develop the preferred upgrade arrangement. The FEA provided good insights into potential issues with the dam/foundation interface and dam stability, and allowed us to focus additional investigations specific to this aspect of the design.
Entura provided construction support for the first stage of the upgrade, which was completed in late 2014.
Outcome
Entura reviewed the proposed concept design and developed a superior upgrade option that resulted in a reduction in capital works in the order of A$30 million through staging to meet both dam safety risk and regulatory requirements. A preferred staged upgrade to address the dam safety deficiencies at Moogerah Dam has now been designed and the initial stage of construction has been completed.
