Note: The following content will not be updated and is provided for historical reference.
On 7 March 2011, the Department of Environment and Resource Management released Seqwater's Report on the operation of Somerset and Wivenhoe dams during the January 2011 flood event.
This report addresses compliance with the Manual of Operational Procedures for Flood Mitigation at Wivenhoe Dam and Somerset Dam and the scope for potential changes in dam operational arrangements related to flood mitigation.
The report also includes Seqwater's assessment of the January 2011 Flood Event, their operational response during the event and compliance with the manual.
Due to its size the report has been provided as a full report and broken into a number of parts.
On 20 January 2011, the then Minister for Natural Resources, Mines and Energy and Minister for Trade, Stephen Robertson, released a redacted version of the Manual of Operational Procedures for Flood Mitigation at Wivenhoe Dam and Somerset Dam (PDF, 1.7MB).
This manual has since been superseded. The latest version of the manual can be downloaded from Seqwater.
On 5 December 2011 the State Government received an independent report investigating options for increasing the flood mitigation performance of Wivenhoe Dam.
Undertaken by engineering consultants GHD Pty Ltd, the report is available for download (PDF, 6.4MB).
A copy of the report was provided to the Commission of Inquiry.
The report examines options for raising the Wivenhoe Dam walls.
GHD recommended that caution should be applied in drawing conclusions due to the potential for significant variability in actual flood events, such as flood patterns and flood risk.
A more detailed assessment of a larger range of scenarios using a more complex hydrologic model is considered necessary.
The GHD report will contribute to the longer term Wivenhoe and Somerset Dam Optimisation Study (WSDOS)—initiated by the Queensland Government in response to the Inquiry's Interim Report. Seqwater, the operator of the Wivenhoe and Somerset dams, is coordinating the WSDOS project.
The former Department of Environment and Resource Management released Seqwater's Report on the operation of North Pine Dam during the January 2011 flood event (PDF, 6.6MB).
The Seqwater report addressed matters including a summary of the flood event, the operations of the flood operations centre, data collection and communications, conclusions about compliance, and recommendations for a formal review of the manual which will occur under standard requirements following an event of this nature.
The current version of the Manual of Operational Procedures for Flood Mitigation at North Pine Dam can be downloaded from Seqwater.
Some sections of the Manual and Report that the dam operator Seqwater considered could be of concern in relation to the security of critical infrastructure were redacted by Seqwater before release. The complete documents have been provided to the Commission of Inquiry.