Burrinjuck Dam Access Upgrade

NSW
State Water
2012 - 2013

Abergeldie was engaged by State Water to upgrade access to Burrinjuck Dam, where access had remained unchanged for 100 years. The project aimed to address OHS risks associated with the outdated cableway used to transport personnel, while also improving logistics for material handling during operations and maintenance. The project involved the design, fabrication, installation, construction, testing, and commissioning of a new steel-trussed bridge as an alternative route across the southern spillway from the dam parapet to the cableway tail tower. New stairs and access platforms were also installed to enhance overall site accessibility.

Scope of works

The scope of work included: 

  • Construction of a galvanised steel-trussed access bridge from the southern end of the existing dam parapet wall to the cableway tail tower.
  • Installation of new access stairs and walkways from the dam parapet wall to the tops of the southern and northern spillway crests.
  • Construction of new access platforms and stairways from the dam parapet wall to the tops of the southern and northern spillway trainer walls, with additional stairways descending along the trainer walls.
  • Completion of bridge footings, headstocks, bearings, waterproofing, and all necessary ancillary elements.
  • Installation of superstructures including handrails.
  • Modification of the existing dam crest and wall structure to accommodate the central pier supporting the new access bridge, stairs, and platforms for the spillway access walkways.
  • Structural assessments for foundations, abutments, and pier footings.
  • Geotechnical assessments for the southern bridge abutment.
  • Rock cutting and anchor/bolt support works for the southern abutment.

Safety focus  

Given the remote project site, the team prioritised emergency response and evacuation procedures. Extensive safety training was conducted for working at heights which was essential for tasks involving abseiling harnesses on steep rock faces above the dam and using a man-box suspended up to 140m above the riverbed.

Dual lift of central bridge span 

The excessive length and weight of the bridge's central span, which exceeded the capabilities of the cableway, and the tower crane individually meant an innovative "dual lift" method was implemented. This method, a first at the Burrinjuck Dam, required meticulous planning and comprehensive crew training. The successful dual lift resulted from the collaborative efforts between Abergeldie and State Water. The pre-assembled central span was lifted simultaneously by both the tower crane and the cableway, then carefully positioned and secured between the first and third spans.

Futureproofing Burrinjuck Dam 

Burrinjuck Dam and its hydroelectric generation plant are important contributors to environmental amenities in nearby and downstream communities. The new access facilities improve the operations and maintenance crews’ ability to ensure that the dam operates efficiently to serve downstream irrigation water and electricity supply.

Constructed from galvanised steel, the bridge is designed for a 100-year lifespan. Its durable, scratch-resistant finish requires no in-situ re-coating for many years, thereby eliminating the risk of paint spills into the river during future maintenance.