Detailed Planning

Transgrid is developing the proposed HumeLink to provide a new transmission connection to reinforce the NSW Southern Shared Network and increase transmission capacity between new generation sources, including the expanded Snowy Hydro and demand centres.

The project will connect Wagga Wagga, Bannaby and Maragle via anew 500-kilovolt transmission line. The project will include:

  •  Substation works:
    • A new substation (Gugaa 500/330 kV (Gugaa 500 kV)) located approximately 15 km east of the existing Wagga 330/132 kV substation (Wagga 330 kV)
    • Augmentation of the existing Wagga 330 kV and Bannaby 500/330 kV (Bannaby 500 kV) substations.
  • New transmission line circuits between:
    • Maragle 500 kV substation and Bannaby 500 kV substation (276km)
    • Maragle 500 kV substation and Gugaa 500 kV substation (108km)
    • Gugaa 500 kV substation and Bannaby 500 kV substation (296km), and
    • Existing Wagga 330 kV substation and new Gugaa 500 kV substation (15km).
  • Ancillary development:  
    • Two telecommunication huts along the transmission lines
    • New and upgraded temporary and permanent access tracks and roads, and
    • Temporary facilities required for construction of the proposal.

Key Dates

Jul 2021 Project Assessment Conclusions Report published
Dec 2021 Expected final investment decision and AER approval
Nov 2022 Expected EIS approval
Jul 2024 Expected Construction Commencement
Dec 2026 Expected Construction Completion


Debt Finance: Federal Government

The Federal Government committed $66 million in underwriting for the project.


Procuring Agency: Transgrid


Dec 2018 The Energy Security Board's Integrated System Plan - Action Plan stated that AEMO is working with Snowy Hydro and Transgrid to refine and extend ISP modelling to better understand the costs, benefits and factors that affect the timing of HumeLink.
Jun 2019 Transgrid published the Project Specification Consultation Report (PSCR).
Jul 2019 AEMO released an Insights paper in support of the 2018 ISP, which flagged the need to accelerate the project timeline in preparation for Snowy 2.0.
Jan 2020 Transgrid published the Project Assessment Draft Report (PADR), which suggested the preferred option for HumeLink as Option 3C. Option 3C provides more opportunity for route diversity, which will provide greater resilience to ‘high impact low probability events’ and unlock new renewable energy resources in the region, such as Snowy 2.0.
Jan 2020 The Federal Government announced the signing of a $2 billion deal with the NSW Government, which includes joint underwriting of delivery of the HumeLink project. However, specific allocation of funding was not confirmed.
Jul 2020 Project Assessment Conclusions Report Published (finalisation of RIT-T process).
Jul 2020 In its 2020 Integrated System Plan, AEMO identified HumeLink as a critical project and provided updated costings for the project.
Mar 2021 Transgrid identified two preferred route options for the project. The preferred route is expected to be announced later this year. The two options include: a new route within Green Hills State Forest which moves transmission across public land instead of private farmland, and a new route east of Barlow and north of Blowering Reservoir, avoiding Tumut Airport.
Jul 2021 Transgrid published the Project Assessment Conclusions Report (PACR).
Sep 2021 Transgrid refined the project corridor for the project. The changes include the removal of proposed transmission lines between Book Book and Gobarralong, and Maragle and Yaven Creek. In addition, a new connection between Yaven Creek and Gilmore will be introduced, and a new corridor option through Tumut will be assessed.
Feb 2022 Transgrid submitted a Request for the Secretary's Environmental Assessment Requirements (SEARs) to NSW Department of Planning and Environment, for the Project's State Significant Development application.
Mar 2022 The NSW Department of Planning and Environment issued the Secretary's Environmental Assessment Requirements (SEARs) for the preparation of the Environmental Impact Statement (EIS) of the project.
Apr 2022 The Federal Government released a Pre-election Economic and Fiscal Outlook (PEFO) which committed $66 million to underwrite the project's early works.