Massive roof replacement project recognised for engineering excellence

The Hope Valley Water Storage Tank Roof Upgrade was recognised at the 2018 South Australian Excellence in Engineering Awards for excellence in building and structures engineering.

The AUD21.6 million project, delivered by SA Water, GHD and York Civil, received an Excellence Award at the annual Engineers Australia event, which recognises and rewards outstanding achievements as well as the valuable contribution engineering makes to the economy, community and the environment.

Originally built in 1955, the 136 megalitre (ML) storage tank is SA Water’s largest water storage facilities in metropolitan Adelaide, supplying water to more than 100,000 properties in Adelaide’s north-east.

The tank upgrade was part of SA Water’s wider AUD89 million program to refurbish 111 water tanks across South Australia between 2016 and 2020. The main part of the works at Hope Valley involved removing and replacing the roof, after the need was identified by a condition assessment.

SA Water engaged GHD to undertake preliminary investigations and establish options for rehabilitation of the structure. In 2016, SA Water, GHD and York Civil worked together to develop the concept and detailed design for the upgrade.

“With only nine months for removal of the roof, construction and commissioning, an innovative and highly collaborative approach was crucial to delivering the project safely, on time and on budget,” says GHD Project Director, John Ewers.

Spanning a space larger than a FIFA soccer pitch and holding enough water to fill 55 Olympic-sized swimming pools, works on the Hope Valley Terminal Storage Tank required up to seven cranes on site at any given time.

The team used 3D modelling to coordinate the cranes on this highly constrained site. With more than 4800 movements over a 190-day period – equating to one lift or movement per crane every 90 minutes – the project stands out in industry practice for effective, continual crane management.

The project team also used remotely-operated robots to inspect the structure and carry out demolition safely.

The new storage tank features an innovative lightweight and cost-effective structural roof cladding solution.

The refurbishment project means this significant facility can continue to serve local residents into the future.

“The safe delivery of this project on time and on budget was achieved thanks to a collaborative, holistic, whole-of-life approach to design and construction using Safety in Design principles,” says SA Water Senior Program Manager Paul Phillips.

“Together, we worked through the project from early investigations to completion, with safety as our number one priority.”