The Rookwood Weir project is a major infrastructure project in Queensland, Australia.

 

It involves the construction of a weir (Dam) on the Fitzroy River near Rockhampton, which will create a new storage reservoir for water supply, irrigation, and flood mitigation purposes.

The main purpose of the Rookwood Weir is to provide a secure and reliable water supply for the region, particularly during periods of drought.

 

 

 

 

 

Once completed, the weir will have a storage capacity of 76,000 megaliters, making it one of the largest weirs in Queensland. In addition to water supply, the Rookwood Weir will also support agricultural and horticultural development in the region by providing water for irrigation. This is expected to boost agricultural productivity and economic growth in the area.

 

Furthermore, the weir will help to mitigate the risk of flooding in the region by storing excess water during heavy rainfall events. This will help to protect the local community and infrastructure from potential flooding and reduce the impact of future flood events.

 

BAUER Foundations Australia Pty. Ltd., a subsidiary of BAUER Spezialtiefbau GmbH, was awarded by Acciona to construct a cut-off wall (COW) by means of diaphragm wall. Target: to mitigate backward erosion at left bank.

 

• Owner: SunWater
• Client: Acciona
• Engineer: GHD
• Execution: Bauer Foundation Australia Pty Ltd

 

Location

The site of the Rockwood Weir project is located approximately 65 km south-west of Rockhampton, Queensland.

 

Scope of works

Plastic concrete cut-off wall. In total 3,920 m². The CoW consists of twenty-three [23] panels spanning approximately 112 linear meters, with depths ranging from 30 m to 44 m. Including embedment into bedrock (basalt and andesite). The 23 nos panels are installed with a maximum length of approx. 7.4 m for the “primary” panels in a 3 “bite” sequence with these being closed-up with “secondary” panels, forming the overcut on each side. CoW thickness 800 mm.

 

Geological conditions

Left bank geology: Heterogenic layers consisting of clayey/silty sands, sand, gravelly sand/sandy gravel, material with significant cobble component, and Rockwood Volcanics (basalt/andesite). UCS values of bedrock (basalt and andesite) varying in a range of 20 MPa to 100 MPa.

 

Equipment

The excavation was performed using

• BAUER BC 48 trench cutter on BAUER MC 96 duty cycle crane
• HS855 with grab
• Mixing, storage and desanding units

 

Miscellaneous

Additionally, BAUER has been involved in the preliminary stage of the project, which includes reviewing the project performance criteria such as permeability, UCS (min and max), strain at failure, and elastic modulus. BAUER also provide the construction procedure for the plastic concrete cut-off wall, including performance criteria and embedment depth.

 

Construction period

Works started in June 2023 and were successfully completed in July 2023.