Transmission line conductor replacement of Circuits M30A/M31A in Ottawa

Hydro One crews have begun construction on the transmission line conductor replacement of Circuits M30A/M31A. These circuits are a vital connection point for Hydro One and Ottawa Hydro and supply electricity to the Ottawa region.

These transmission circuits travel along the Hydro One corridor between the Hawthorne Transmission Station (TS) and Merivale TS.

The project involves the replacement of the existing conductor (wire), reinforcement of the existing transmission structures where necessary and the installation of temporary bypass structures to facilitate the construction process. Work will be carried out within the existing transmission corridor and, where possible, access to the transmission structures will be gained using existing roads, transmission corridor and trails. There will be little noticeable difference in this transmission line after the project has been completed and no residential outages are planned.

Map of Hawthorne to Merivale project area
Click to enlarge (.PDF)

The Process

This transmission line refurbishment was subject to the Class Environmental Assessment for Minor Transmission Facilities (2022), in accordance with the Ontario Environmental Assessment Act. The Class EA is a streamlined planning process that has proven effective in ensuring that minor transmission projects that have a predictable range of effects have feasible environmental mitigation and/or protection measures in place.

A Class Environmental Assessment for Minor Transmission Facilities was completed for this project in July 2020.

Community Engagement

Community engagement and consultation is important to Hydro One. We are committed to keeping community members informed about important infrastructure projects like this one. Hydro One hosted a community information centre on November 2, 2021.

Download the notice (aussi disponible en français

Download the information panels presented at the Community Information Centre

Project Timeline
  • July 2020
  • Environmental Assessment complete

  • April 2021
  • Leave to Construct Approval from Ontario Energy Board

  • Oct 2021
  • Corridor preparation activities to begin

  • 2022–2023
  • Construction activities along corridor

  • Winter 2023
  • Target In-Service date

Contact Us

Melissa Rozycki
Community Relations
Hydro One