Dams and flooding
Dams are important infrastructure used for water storage and flood mitigation. Dams are designed to mitigate flooding by temporarily detaining water during storm events and releasing that water in a controlled way to reduce downstream flooding. As the dam fills up and water reaches a set level it releases water. This is commonly referred to as a dam spill. All dams in the Brisbane Local Government Area are ungated which means the water is not controlled through the operation of gates. These dams are designed to spill when the water level gets too high.
In some circumstances, a dam spill may result in downstream flooding which may cause localised flooding and localised road closures.
Some dams are deemed ‘referable dams’ under state government legislation This is determined by an assessment that shows there is the potential risk of two or more people being impacted by downstream flooding.
In extreme circumstances, dams can also release water in an uncontrolled way. For referrable dams, where downstream hazards for uncontrolled releases is significant, this process is managed through an Emergency Action Plan. Emergency Action Plans are managed through the dam owner.
Brisbane City Council owns the following dams:
- Forest Lake Dam, Forest Lake
- Gordon Road Detention Basin, Bardon.
There are four dams within the Brisbane local government area that are owned by Seqwater:
- Enoggera Dam, the Gap
- Gold Creek Dam, Brookfield
- Lake Manchester Dam, Lake Manchester
- Leslie Harrison Dam, Capalaba. This dam is located between Brisbane and the Redland City Council local government area.
There are three dams located outside of the Brisbane local government area that are owned by Seqwater where spills may impact parts of the Brisbane local government area:
- North Pine Dam, Strathpine
- Somerset Dam, Kilcoy
- Wivenhoe Dam, Fernvale.
- Council encourages residents to sign up to the free Early Warning Alert Service
- Seqwater has a free opt-in Dam Release Notification Service
How to prepare
- Understand your flood risk
- Read the emergency action plan for the dam. Read further information on emergency action plans for each dam
- Have an emergency plan in place
- Have an emergency kit
- Sign up to the free Early Warning Alert Service