Australian utility SA Water commissioned SMEC to provide the design of major upgrades to the Mount Bold Dam – South Australia’s largest dam – allowing the structure to meet current guidelines from the Australian National Large Dams Committee. (ANCOLD).
The Mount Bold Dam is considered critical infrastructure as it is the largest storage in the region with a total capacity of around 46 billion liters, providing 40% of the Adelaide metropolitan area’s water supply. .
The new upgrade will bring the Mount Bold Dam into line with current guidelines by reinforcing the mid section of the dam wall arch by shoring it with mass concrete and reinforcing the abutment sections of the gravity dam existing with post-tensioned anchors to bedrock. It will also remove existing spillway gates and the need for manual operation, provide a free-flowing spillway to safely pass the full range of floods, including flood mitigation for floods. frequent, and will incorporate a saddle-fill dam to prevent runoff over a small section lying on the edge of the reservoir.
Ultimately, the upgrade will strengthen the dam to safely pass flooding and seismic events, while providing limited flood protection to the downstream community.
âWe are proud to have been chosen as the designer of the project,â commented Francisco Lopez, responsible for the design of the SMEC project. âThis is a critical role that helps protect one of the Adelaide community’s most important infrastructure assets. Much has changed since the dam was first built in 1938 and improved in the 1960s, meaning there is a need to re-evaluate and improve the Mount Bold Dam to meet current guidelines for ANCOLD and industry standards. For example, the ability to withstand maximum probable floods and seismic loads are the two key areas that will be addressed during the design phase.
Built between 1932 and 1938, the Mount Bold Dam was designed and built as a water supply dam with the aim of maximizing storage levels. The dam is a critical and cost-effective water supply asset while providing flood mitigation benefits to downstream communities through controlled water discharges. Water is also pumped into the Mt Bold Dam from the Murray River.
SA Water anticipates that the detailed design of the upgrade will be initiated and completed in 2022. Construction is expected to begin in 2023 and take approximately three and a half to four years to build, providing a safer and more secure asset for the future. .