Eastern CBD 11kV Cable Project


Electrical cable low voltage

Contract Type

ECI, Design and Construction

Year of Completion




Eastern CBD 11kV Cable Upgrade: Route to Resilience

Revitalising Sydney’s electrical infrastructure to ensure uninterrupted power for the CBD, blending technical excellence with community care.

Project Overview

Diona was engaged by Ausgrid to extend the operational life of Sydney’s electrical network, focusing on the transition from the ageing City East Substation in Woolloomooloo to the Belmore Park Substation. The Eastern CBD 11kV cable project encompasses the design and construction of new underground cables stretching 1.8 kilometres through the eastern sector of Sydney’s CBD, traversing key streets to ensure a continuous and reliable electricity supply for local customers.

Project Need

The City East Substation, nearing the end of its design life, necessitated a robust solution to maintain electricity supply in Sydney’s bustling CBD. Upgrading the 11 kV cables became imperative to shift the supply load to the Belmore Park substation, addressing the critical need for infrastructure renewal to support the city’s growing energy demands and ensure uninterrupted service for residents and businesses.

Project Solution

The upgrade involved laying new underground 11 kV cables along a 1.8-kilometre route through Sydney’s bustling CBD. Recognising the challenge of high traffic volumes, the majority of construction was planned for night shifts to minimise disruption. For major intersections where night work was impractical, 56-hour weekend shutdowns were scheduled. These critical operations demanded rigorous coordination with stakeholders, ensuring the project’s seamless progression. Diona’s adoption of state-of-the-art cable pulling techniques and non-destructive digging methods underscored the project’s innovative approach, balancing efficiency with safety and environmental consideration.

Value Add | Benefit
Infrastructure Resilience

This project significantly enhances the resilience and reliability of Sydney’s electrical infrastructure, ensuring the CBD remains powered without interruption.

Innovation in Execution

Through the adoption of innovative cable pulling techniques and meticulous planning, Diona showcased its capability to address complex urban infrastructure challenges.

Community and Stakeholder Engagement

Recognising the importance of community impact, the project included proactive engagement efforts, from regular updates to direct communication, ensuring transparency and minimising disruption.

Safety and Environmental Stewardship

With a zero-injury outcome and the use of non-destructive digging methods, the project highlighted Diona’s prioritisation of health, safety, and environmental care throughout the project lifecycle.

ESG Alignment

Demonstrates a commitment to preserving urban ecosystems and ensuring a resilient energy future.

The upgrade of the 11kV cables for electricity supply in Sydney’s CBD supports the goal of ensuring access to affordable, reliable, sustainable, and modern energy for all. Upgrading the energy infrastructure contributes to the efficient and sustainable energy supply in urban areas.

The design and construction of new underground cables through a busy urban centre demonstrate innovative approaches to infrastructure development. This aligns with the goal of building resilient infrastructure, promoting inclusive and sustainable industrialisation, and fostering innovation.

By enhancing the reliability and efficiency of the electricity supply in the eastern part of Sydney’s CBD, the project contributes to making cities inclusive, safe, resilient, and sustainable. Reliable energy infrastructure is crucial for the functioning of a modern city.

Upgrading the electrical infrastructure to more efficient systems contributes to climate mitigation strategies by supporting energy efficiency. This aligns with the goal of taking urgent action to combat climate change and its impacts.

The collaboration between Diona, Ausgrid, local authorities, and other stakeholders in the CBD for this complex infrastructure project highlights the importance of partnerships in achieving sustainable development goals, especially in urban settings.