Search the site

Wivenhoe and Somerset Dams Optimisation Study

The Wivenhoe and Somerset Dams Optimisation Study (PDF, 12.7MB) (WSDOS) presents options for the management of the Wivenhoe and Somerset dams during the event of a flood.

The options presented seek to improve the use of existing dam infrastructure during a flood to deliver better flood mitigation outcomes. This study was completed in response to recommendations of the Queensland Flood Commission of Inquiry's final report.

Discussion Paper

A discussion paper (PDF, 914.3KB) has been developed as a guide to understanding the WSDOS Report, and provides an overview of what the study involved in addition to the preferred option.

The preferred option changes how the flood mitigation compartment of Wivenhoe Dam is used, allocating more space to protect houses and buildings from damage during a large flood and potentially deliver 5 to 10 per cent less flooding during a major flood.


The Queensland Government is seeking your feedback on the options presented in the WSDOS Report. We are particularly interested in feedback on the most promising new option, labelled in the report as "Alternative Urban 3".

You can provide feedback in the following ways:

Get Involved: This will be available soon
Phone: 13 QGOV (13 7468)


Public consultation meetings will be held throughout the Brisbane region in Ipswich, Fernvale, Somerset and CBD locations. Details of the sessions will be updated on this page closer to the time.

To register your interest and receive a notification when the consultation sessions are scheduled, please email your name and post code to the above address. Providing your post code will assist us in scheduling the most convenient locations for those wishing to attend.

About the Wivenhoe and Somerset Dams

The Brisbane River catchment has an area of about 15,000 km2 extending from Moreton Bay to the Great Dividing Range. This catchment includes the major sub-catchments of the Upper Brisbane, Stanley and Bremer rivers and Lockyer Creek. Average annual rainfall ranges from 1,700 mm at Peachester above Somerset Dam to 730 mm at Cooyar near the western boundary.

Wivenhoe Dam accounts for about 50 per cent of the total Brisbane River catchment area and is one of the largest storages in Queensland. The dam catchment receives approximately 1,000 mm of rainfall annually, mostly occurring in summer. It has a full supply volume of 1,165,000 megalitres for urban water use (including drinking water), and an additional temporary flood storage of approximately 1,450,000 megalitres.

Somerset Dam drains into Wivenhoe Dam and is operated concurrently during floods to maximise the flood mitigation benefits downstream of Wivenhoe Dam. Somerset Dam has a full supply volume of 380,000 megalitres for urban water use (including drinking water), and an additional temporary flood storage of approximately 524,000 megalitres.

Last updated
1 April 2014