Works to repair the damage in the Morwell River Diversion near the Yallourn coal mine in Victoria have been agreed upon between the state government and EnergyAustralia.
The Yallourn coal mine is operated by EnergyAustralia and provides more than 20 per cent of Victoria’s energy supply.
Significant flooding in the Morwell River from damaging storms in June resulted in cracks in the MRD that threatened to inundate the Yallourn Coal Mine.
With Yallourn Power Station providing more than 20 per cent of Victoria’s energy supply, an emergency declaration was made to plan for the risk.
While short-term repair works have temporarily stabilised the situation, the MRD and the Yallourn coal mine remain at risk of a significant rainfall event.
Failure of the MRD would see the Morwell River inundate the coal mine, which would in turn impact power production and downstream environments.
The state government has accepted EnergyAustralia’s proposal that will ensure necessary repairs not only secure Victoria’s energy supply but protect mine workers, the South Morwell community, water entitlement holders and the environment.
Based on technical assessments and safety considerations for the mineworkers, repair work will see EnergyAustralia divert normal winter flows from the Morwell River around the damaged MRD and into the Latrobe River.
The diversion will dry the MRD, enabling engineers to undertake necessary repairs.
EnergyAustralia chief operating officer Liz Westcott said the MRD saw more than 30 times the standard volume of water impact the area and assured the community that water diversion activities will continue to meet strict environmental conditions set by the state government and enforced by the Environment Protection Authority.
“As a result of recent Victorian Government approvals, we are now able to proceed with relieving pressure around the impacted area of the Morwell River Diversion, understand the extent of damage and assess what longer-term repairs might be required,” Westcott said.
“We’ve held real fears since June that with a compromised structure and an unknown amount of damage in the low flow channel, we can’t confidently withstand further flood events.
“Ensuring we continue to safeguard the surrounding environment, we have implemented an extensive monitoring regime of water properties with sampling frequency increased from weekly to three time per week, which will continue through the diversion recovery program.
“We commit to make public a summary of our monitoring data that’s being collected throughout the process later in the year, once it has been analysed.
“EnergyAustralia appreciates the strong support of the Victorian Government, local community, unions, regulators – and especially our Yallourn workforce.”
Member for Eastern Victoria Harriet Shing said the situation is a complex and urgent matter, which has required extensive works to maintain the mine and reliable energy supply.
“This is a complex and urgent matter, which has required extensive works to maintain the mine and reliable energy supply,” Shing said.
EnergyAustralia will be able to divert up to 3500 megalitres per day to the Latrobe River.
If the area receives heavy rain larger flood flows may be diverted into the Hazelwood Mine Void, upstream of Yallourn until flows return to normal.
In an emergency, the unused Township Field in the Yallourn coal mine can be used as a one-off storage for up to 3000 megalitres.
Construction and repairs are estimated to take up to 18 months to complete.