Waasigan Transmission Line Project Logo 
Hydro One wants to support growth in northwestern Ontario and energize life for communities and businesses in the region. Energizing life means more than supplying safe and reliable power, it means listening and taking action to meet your needs. The northwest has advocated for an increase in power for many years to support community and industry growth.

We are investing in the development work for the Waasigan transmission line now so that power is available when it’s needed.

First Nations partners  ​

Project Overview

The Waasigan transmission line is a proposed new double-circuit 230 kilovolt transmission line between Lakehead Transformer Station (TS) in the Municipality of Shuniah and Mackenzie TS in the Town of Atikokan, and a new single-circuit 230 kilovolt transmission line between Mackenzie TS and Dryden TS in the City of Dryden. Northwest Ontario needs access to more power by as early as the mid-2020s to meet growing electricity demand. We are completing development work now, including an environmental assessment, so that we’re ready to support the region’s electricity needs.

Waasigan will bring an additional 350 megawatts of electricity to the region, which is more than two times what it takes to power the City of Thunder Bay. This increase in power transfer capability means communities and businesses can grow. ​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​

Waasigan Transmission Line Map

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Waasigan Transmission Line Map Enlarge (.PDF)

Environmental Assessment (EA) Process

An environmental assessment includes consultation and engagement with Indigenous communities, government officials and agencies, and interested persons and organizations. The process is designed to assess the existing environment and mitigate potential effects before decisions are made about proceeding with a proposed project. Waasigan requires completion of a comprehensive environmental assessment under Ontario’s Environmental Assessment Act.

A comprehensive environmental assessment has two parts: first, the development of a Terms of Reference and then the environmental assessment. The Terms of Reference is a document which provides the framework for how the environmental assessment will be completed, including outlining studies and consultation activities that will be completed, as well as identifying viable alternative routes. Hydro One received approval from the Ministry of the Environment, Conservation and Parks for the amended Terms of Reference in February 2022. With this approval, Hydro One began the environmental assessment in March 2022, as outlined in the approved Terms of Reference.

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  • April 2019
  • Notice of commencement of the Terms of Reference for the environmental assessment

  • Spring 2019 -
    Spring 2020
  • Consultation, data collection, and development of corridor alternatives

  • June 29 -
    Aug 14 2020
  • Draft Terms of Reference review

  • Fall 2020
  • Proposed Terms of Reference submitted to the Ministry of the Environment, Conservation and Parks

  • February 2022
  • Terms of Reference approved by Ministry of the Environment, Conservation and Parks

    9, 2022
  • Notice of Commencement of environmental assessment

  • 2022 - 2023
  • Consultation and data collection on environmental assessment study areas

  • Winter
  • Selection of a preliminary preferred route​

  • ​Spring​​/Summer 2023
  • Draft environmental assessment public review and comment period, followed by addressing comments received during this period

  • Spring/Summer 2023
  • Su​bmit final environmental assessment to the Ministry of the Environment, Conservation and Parks

  • 2023
  • Leave to Construct (Section 92) application submission to the Ontario Energy Board*

  • 2024
  • Decision on Environmental Assessment by Ministry of the Environment, Conservation and Parks

  • 2024
  • Leave to Construct (Section 92) application approval from the Ontario Energy Board (anticipated)​

  • By end
    of 2024
  • Complete development work

*Leave to Construct under Section 92 of the Ontario Energy Board Act, 1998 is a regulatory process to obtain approval from the OEB to build and operate a transmission line. Hydro One will not apply for this approval until direction is received by the IESO to proceed with the project.


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Project Approvals

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Public Consultation

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Working with Indigenous Communities

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To provide comments or to be added to the project contact list, please call or email:​​