Eastern CBD 11kV Cable Project
Ausgrid’s City East Substation in Woolloomooloo was reaching the end of its design life and would shortly be retired. The 11kV cables in the eastern part of Sydney’s CBD needed to be upgraded to transfer electricity supply for local customers to the Belmore Park Substation on the corner of Hay Street and Pitt Street.
Diona was engaged to design and construct new underground 11kV cables along a 1.8 kilometre route through Macquarie Street, College Street and Wentworth Avenue in the eastern part of Sydney’s CBD.
Due to high traffic volumes in the CBD the majority of the works were carried out at night under strict ROLs, generally between the hours of 9 pm and 5 am. Each night our team would mobilise to site, set up traffic control as per approved TCPs, excavate, lay conduit, backfill and reinstate carriageway with the use of road plates as per RMS Road Opening and Restoration standards.
The cable route involved crossing several major intersections across the Eastern CBD. As nightshift works were not feasible, instead the works were carried out over 56-hour weekend shutdowns. These were planned months in advance and involved coordinating with Sydney Coordination Office, Sydney Transport, NSW Police, the relevant service stakeholders (Ausgrid, Jemena, Optus, etc.) as well as our subcontractors.
Innovation was at the forefront when it came to cable pulling works. Diona utilised a wide range of cable stands, rollers and winches to suit the various cable installations on the project. From 600-metre-long pulls through multiple pits along College Street to the more complex pulls from existing pits into Belmore Substation, our in-house design team and experienced crews on the ground were on-hand to deliver a solution at every turn.
Health and safety was a top priority on this project. Service location and identification was a core part of the project and not only informed the design but was an important part of our excavation procedures. Non-destruction digging methods were utilised both at the site investigation and trenching stages and service locators were engaged regularly to prevent any service strikes.
Given the nature of the works, community engagement was a key aspect of the project. Our community team provided weekly website updates to inform the local residents of exactly where our crews would be working, how the works were progressing and the measures we were taking to reduce impact. They also undertook frequent letter drops and door-to-door visits.
Diona delivered a successful project on time, on budget and with no lost time injuries which was achieved through great teamwork and communication between project management, site crews and stakeholders alike.
Diona should be congratulated on completing this very successful project to the requirements of the contract specification in a manner that met Ausgrid’s expectations in full. I would recommend Diona for any infrastructure project and I look forward to working with them in the future.G. Doherty - Project Manager - Ausgrid CBD Project