Callide Dam safety and emergency management

Callide Dam Gates Project

Callide Dam, Biloela, Queensland

This maintenance project has been set up to investigate, repair and restore Callide Dam’s gates to address intermittent occurrences of vibration during their operation. This project will ensure ongoing dam safety and long-term water security.

Safety and emergency management

In June 2021, Sunwater issued a Section 399B notice to the Dam Safety Regulator. This notice means that Callide Dam is now operating at a reduced full supply level (FSL) to enable work to be completed as part of the Callide Dam Gates Project.

The top of the concrete spillway crest became the maximum height of the dam (100 per cent) and the temporary FSL, and the project’s operational level was set at 69 per cent.

Prior to issuing the notice, the top of the concrete spillway crest represented 41 per cent of the dam’s capacity, however, throughout the project Sunwater will refer to the top of the concrete spillway as the dam’s FSL of 100 per cent.

In the instance of extreme weather events, the water level reaching 100 per cent signals a forthcoming spill.

As investigations and some of the work to resolve the gate vibrations are now complete, the dam’s operating level has been increased from 69 (38,160ML) to 94.1 per cent (52,098 ML) of the temporary full supply level.

The increased operational level will allow for approximately 14,000 more megalitres to be stored in Callide Dam, should it receive further inflows this wet season.

In instance of inflows and the storage reaching higher than 94.1 per cent, slow releases will be required to return the storage to the project operational level as soon as possible. If a weather event occurs where it is expected that water will reach the fixed spillway crest, the gates will be manually and safely raised above the water level.

This change will not impact the Callide Dam Emergency Action Plan and based on ‘fill and spill’ scenario mapping of historical Callide Dam data, between the months of December 2021 and May 2022, the probability of Callide Dam spilling remains low. We expect the temporary FSL will have little impact.

The Sunwater app provides the latest dam information and alerts at your fingertips. Download the app from the Apple App Store or Google Play Store to stay informed about Sunwater dam operations especially during heavy rain and flood events.


How helpful was this page?
.

Provide feedback