Storm King Dam work under way
THE first stage of more than $1 million of safety upgrades for Storm King Dam has been completed, with the Southern Downs Regional Council having recently replaced several aging valves.
The 57-year-old valves weighed half-a-tonne each and were replaced for the first time since the dam was constructed in 1954.
It took a precision operation and several specially trained council workers to remove the aging equipment from the dam's "wet well", with SDRC director of engineering Peter See saying the dam was more than capable of withstanding a major flood in its current condition.
But he said the work had to be done for the dam to be compliant with the State Government's dam safety regulations.
"The dam, currently, is capable of withstanding any major floods that is likely to occur in its lifetime," Mr See said.
"However, the State Government has decreed that because it is upstream of Stanthorpe, it must be able to withstand the worst flood possible.
"This flood is unlikely to occur, however, should it occur in the future these works will ensure that Stanthorpe will not be affected by the dam failing."
The main valve which controls the flow of water through the trunk main has been replaced as well as the valve that is used to lower the dam's water into Quart Pot Creek.
"To enable replacement of the valves, the 'wet well' in the dam wall had to be shut down and a bypass line installed over the dam wall to the raw water trunk main," Mr See said. "The bypass work was a substantial and complex job requiring multiple pieces of equipment and 20 staff working simultaneously."
Council will now look at strengthening the dam wall by undertaking post tensioning work to anchor steel cables vertically through the dam wall into the bedrock, at a cost of more than $1.3 million.
"When we do the stabilisation of the dam wall the water level will need to be lowered to half a metre below the dam wall to allow access for the work," Mr See said.
"Currently the dam is at full capacity."