Early and enabling works to get underway on Somerset Dam Improvement Project

The first stage of the Somerset Dam Improvement Project in Queensland is gearing towards major construction as early and enabling works commence. 

Early and enabling works include: 

• Broad scale geotechnical investigations including installation of dam surveillance instrumentation 
• Removal of existing spillway (radial) gates as these no longer form part of Seqwater’s operation of the dam 
• Replacement of the sluice gates (gates at the bottom of the dam) and outlets that are reaching the end of their serviceable life 
• Construction of a temporary coffer dam that will help to maintain a dry work site downstream when investigations and construction commences in areas currently submerged 
• Relocation of the existing operations facilities to allow construction of the future main dam upgrade 
• Temporary and permanent access road works including a permanent realignment of Esk-Kilcoy Road and a new access to the dam wall from Wivenhoe-Somerset Road 
• A range of investigations, studies and assessments to support finalisation of the Detailed Business Case for the main dam upgrade 

Procurement is also underway for the manufacture of modern, purpose-built and hydraulically operated sluice gates, with tender submissions already received. Manufacturing works will start in 2025 once the contract is awarded and upon receiving project approvals. 

“While dams in Queensland were built to very high, internationally accepted safety standards, Somerset Dam was built by 1959, and dam design and engineering standards have evolved significantly since then. 

“As part of the Somerset Dam Improvement Project, Seqwater is pleased to be planning a range of early and enabling works to support future construction on the major dam upgrade planned at this site. 

“The works are required to be completed irrespective of the final design option for the Somerset Dam Improvement Project, which is currently being considered as part of the Detailed Business Case stage. 

“Subject to project approvals, the majority of the early and enabling works are expected to commence on-site in 2025, and Seqwater will continue to keep the community informed,” Seqwater Interim CEO Will Harpham said. 

Seqwater is planning to host drop-in information sessions in July and August of this year where they will be providing the community with further information about the planned works for the project. More information on the sessions will be released once confirmed. Seqwater is also encouraging community members to sign up for the project newsletter on its website. 

A Detailed Business Case for the Somerset Dam Improvement Project is already in the works, carefully assessing the preferred option for upgrading the dam. Seqwater will continue to keep the community updated as the project progresses. 

The Queensland Government has committed $13 million, through the 2024-25 State Budget, for planning works on the project. 

The Somerset Dam Improvement Project is anticipated to support up to 150 jobs. 

The proposed main dam upgrade includes: 

• Raising the height of the dam wall to improve function during very extreme floods 
• Extending and reinforcing the dissipator basin and training walls, plus adding a new control structure, downstream of the spillway to reduce energy from the spillway flow in very extreme weather events 
• Adding concrete to the downstream face of the dam wall to help strengthen the wall 

“This is an important and complex project to make sure Somerset Dam continues to withstand extreme flood events into the future and provide water security for years to come. 

“Seqwater has already delivered 13 dam upgrades, and I am pleased to see works commencing on Somerset Dam soon as part of this important program of works in the region. 

“There’s going to be around 150 jobs throughout the life of the project,” Minister for Water Glenn Butcher said. 

Source: Queensland Government – Media Statements; Seqwater (1, 2)