Somerset Dam will undergo a minor upgrade ahead of the next wet season to improve dam safety and flood mitigation.
The upgrade is part of the Seqwater’s Dam Improvement Program and will involve constructing a parapet or wave wall on the dam’s breezeway to increase its flood mitigation capacity and safety.
It will involve filling in the bays (gaps) along the breezeway on the upper reaches of the dam with concrete to construct what’s called a parapet or wave wall.
The upgrade is in addition to the new operating strategy and Temporarily Full Supply Level (TFSL) adopted for Somerset Dam during the previous wet season to ensure the dam can continue to operate safely.
Somerset and Wivenhoe dams had their drinking water full supply levels temporarily lowered earlier in the year as part of the Dam Improvement Program.
These levels will be maintained while investigations continue over 2017 into the scope, design and timing of further improvements required for the Somerset Dam.
Somerset has been lowered to 80% capacity. Wivenhoe has been lowered to 90% capacity to ensure the flood mitigations benefits of both dams are maintained.
Seqwater Acting Chief Executive Officer Jim Pruss said the minor upgrade was a common engineering solution designed to increase a dam’s flood mitigation capacity and safety and was similar to the design at Wivenhoe Dam.
“These works are about helping to ensure Somerset Dam can continue to operate safely, particularly in large and extreme flood events, while we finalise details of the longer term improvement works required,’’ he said.
Somerset Dam is currently scheduled for a major safety upgrade in 2025. The ongoing investigations may result in these upgrade works being brought forward.
The lowered dam levels have had a minimal impact on the security of the region’s water supply.
All Seqwater recreation areas at Somerset Dam will remain open throughout the upgrade work.