The North Pine Dam Optimisation Study (NPDOS) will consider options for balancing the competing objectives of dam operations, flood mitigation and water supply security for South East Queensland.
The study is in response to Recommendations 17.3 and 17.9 of the Queensland Flood Commission of Inquiry's final report. The findings of the study will be presented to government in early 2014.
The study will investigate alternative strategies for the operation of North Pine Dam. This includes temporary, permanent or seasonal alterations to the full supply level, dam gate operating procedures and the duration of water releases.
The study will consider the impact of the dam's operations on the closure of downstream crossings and bridges.
The study will generally not be considering new infrastructure or expansion of existing dam infrastructure. However, the results of this study may lead to further investigations of other flood mitigation options (including infrastructure).
DEWS is also leading an optimisation study of the Wivenhoe and Somerset dams.
The results of NPDOS, and the Wivenhoe and Somerset Dams Optimisation Study (WSDOS) will feed into the broader Brisbane River catchment flood study (led by the Department of Natural Resources and Mines) and the development of a Brisbane River catchment floodplain risk management plan (led by the Department of State Development, Infrastructure and Planning).
The findings of this study will be reviewed again when the Brisbane River catchment studies are completed.
North Pine Dam (Lake Samsonvale) is located on the North Pine River, north-west of Brisbane. The dam has a full supply capacity of approximately 214,302 megalitres, supplying urban water (including drinking water) to the Moreton Bay region and Brisbane’s northern suburbs.
The dam has a catchment area of approximately 345 km2, receiving approximately 1,200 mm of rainfall annually, mostly occurring in summer.
While North Pine Dam does mitigate floods to a limited extent, it currently has no planned flood mitigation function. Significant inflows may occur into the dam approximately two to four hours after the commencement of heavy rain.