2004 – Burnett RCC Dam Design – An Innovative Approach to Site Specific Conditions

R. Herweynen, T. Griggs, E. Schrader and D, Starr

The Burnett Dam is a 50m high Roller Compacted Concrete Dam on the Burnett River, located approximately 50km inland from the town of Childers in Queensland. The design and construction of the Burnett Dam is being undertaken by the Burnett Dam Alliance (BDA) consisting of Walter, Macmahon, Hydro Tasmania, SMEC and Burnett Water. The design of the dam commenced in 2003, construction started in November 2003 and the planned completion date is mid 2005.

The Alliance Contract was awarded through a competitive process and therefore innovation was a key aspect of the design and construction methodologies. This paper will look at a number of specific aspects of the design where innovation delivered true value, namely:

• Allowing the right abutment to act as a secondary spillway by utilising the high tailwater levels during the extreme flood events.
• Developing a river diversion strategy, which had the added benefit of addressing a foundation issue and providing source material for aggregate.
• Creating an economical RCC mix design, which uses the available materials effectively to achieve the required properties.
• Designing a dam cross-section with an upstream membrane to eliminate the need for a gallery and assure watertighness and uplift control at the upstream face.

The Burnett Dam design has clearly demonstrated that the unique site conditions have had a significant impact on the final design and construction methods.