Callide Dam Gates Project update

The dual objectives of securing long-term water security for customers and ensuring community safety have been our focus over the past months as we continued planned investigations, testing and early work to find the best possible solution to address Callide Dam’s gate vibrations.

Over the past five months, the following progress has been made:

• Callide Dam’s full supply level (FSL) was temporarily reduced to the spillway crest to enable site establishment.
• A crane pad and temporary access track was constructed to assist in facilitating the works.
• Sunwater continued planned investigations and testing to find the best possible solution to address the gate vibrations.

While our investigations and work to finalise a solution continue, we have determined that the gates can safely remain in place.

Callide Dam is safe, and will be operated in accordance with an amended emergency action plan (EAP), which specifies that:

• if a weather event occurs and it is expected that water will reach the fixed spillway crest, the gates will be manually and safely raised above the water level
• the temporary reduced full supply level at the spillway crest and project operational level (69 per cent) will remain in place.

In the event of inflows and the storage capacity reaching 69 per cent, releases will be made to maintain this level.

We expect the solution to address the gate vibrations will be finalised in 2022, after the wet season. The temporary reduced full supply and operational levels will then be returned to the pre-project level.