Northern and central Ontario

Sudbury Barrie Transmission Line

Building a stronger grid today to provide safe, reliable power for Ontario's growing communities.

Current project phase: Project announcement

Expected completion date: 2032

Community open houses Contact
Arial view of Sudbury's Bell Park

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TX lines in Sudbury

Building a stronger grid for Ontario's future

Project overview

Ontario's long-term demand for electricity is increasing. To help meet this need, Hydro One will plan and build the proposed Sudbury Barrie Transmission Line. The proposed priority project is a new single-circuit, 500-kilovolt (kV) transmission line that will span approximately 300 kilometres from the Hanmer Transformer Station (TS) in Sudbury to Essa TS near Barrie, including station facility expansions. The line is expected to be in service by 2032.

The designation of this project includes the direction to complete development work for a second, new single-circuit 500-kV transmission line. A recommended in-service date for the second line will be determined by the Independent Electricity System Operator.

Once built, this project will strengthen reliability and prepare the system for future growth.

Partnership with purpose

Building as partners

Hydro One and nearby First Nations will collaborate on the planning, development and construction of the transmission line. Through Hydro One's industry-leading First Nation Equity Partnership Model, nearby First Nations will have the opportunity to invest in a 50 per cent equity stake in the transmission line component of the project.

Learn more
Native Friendship Centre in Sudbury

Visit an open house near you

Current open houses

At Hydro One, early and consistent engagement is important for all projects. We invite you to join us in person or online, to meet the project team, learn what we know so far and ask any questions you may have.

Barrie

Monday, April 13, 2026

4 to 7 p.m.

East Bayfield Arena Community Centre, 80 Livingstone Street East

Get directions

Parry Sound

Tuesday, April 14, 2026

4 to 7 p.m.

Royal Canadian Legion Branch 117, 30 Mary Street

Get directions

Hanmer

Wednesday, April 15, 2026

4 to 7 p.m.

Centennial Arena, 4333 Centennial Drive

Get directions

Bracebridge

Thursday, April 16, 2026

4 to 7 p.m.

Bracebridge Sportsplex, 110 Clearbrook Trail

Get directions

Can't visit us in person? Register for our virtual community open house

Tuesday, April 21, 2026 - 6-7 p.m.

Register now

See the project study area

Project study area

The map shows the project study area where route alternatives will be developed.

Share your comments on the interactive map below.

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Project map

See what's coming

Anticipated project schedule

2026
Project announcement and community open houses - round 1
2026
Notice of Commencement of Class EA
2026
Announcement of route alternatives and community open houses - round 2
2026 - 2027
Consultation and data collection in support of Class EA
2027
Notice of preferred route
2027
Community open houses - round 3, to present preferred routes
2027
Release of draft Environmental Study Report (ESR)
2028
Submit final ESR
2028 - 2029
Completion of detailed design, Section 92 approval
2029
Start of construction
2032
Line energized
*Dates are subject to change.

Guided by standards

Planning process

The project will follow the Class Environmental Assessment for Transmission Facilities, 2024 in accordance with the Ontario Environmental Assessment Act. Work on the Class EA will begin with the publication of the Notice of Commencement. This is an important part of the planning process to assess potential natural, economic, social and cultural effects, determine measures to avoid or minimize impacts and evaluate route alternatives.

In addition to the Class EA, the project will require Ontario Energy Board approval under Section 92 (Leave to Construct) of the Ontario Energy Board Act.

People sitting and conversing

What we shared

Public consultation documents

Project notices

March 2026

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What these documents mean

These documents summarize the studies, project notices and resources shared during the consultation process. They explain how routes were evaluated, decisions were made and how we engaged with communities.

Answers at a glance

Frequently asked questions

How are route alternatives selected?

Working alongside our First Nation partners, Hydro One will identify route alternatives by reviewing existing reports and technical studies, mapping technical, environmental, community, and Indigenous value considerations, and looking for opportunities to follow existing infrastructure wherever possible.

How is feedback used as part of the Class EA process?

Your feedback is important. The local knowledge we receive helps us select a route that minimizes impacts on the environment and community. Please provide feedback by contacting Hydro One at: Community.Relations@HydroOne.com or 1-877-345-6799

Why do we need these new transmission lines?

Ontario's long-term demand for electricity is increasing. The Sudbury Barrie Transmission Line project is part of the province's electricity plans to address future growth to build a strong north-south electricity backbone that will connect the north with fast-growing industries in the south. The project will increase transfer capability, support reliability and prepare the system for future growth.

How does this project benefit the community?

The Sudbury Barrie Transmission Line will enhance transfer capability and unlock economic opportunities from northern to southern Ontario. This project will strengthen the electricity system that communities across the region rely on every day, support future growth and help homes, businesses, hospitals and schools continue to have a stable supply of electricity as the province's needs increase.

We've noticed people working in the area — can you explain who they are and what kind of work they're performing?

Over the coming months, you may see environmental consultants working in the community. These teams are carrying out field studies to help us better understand local environmental conditions as we plan the project. Their work may include activities such as surveying vegetation, wildlife, water features and other natural areas. These studies are an important part of the environmental assessment process and help us identify potential impacts and develop appropriate mitigation measures. If you have any questions about the work happening in your area, please feel free to reach out.

Contact us

We're here to help

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

1-877-345-6799

Land acknowledgement

Hydro One acknowledges that the Sudbury Barrie Transmission Line is proposed on the ancestral lands of the Anishinaabe and is now home to many diverse First Nations, Inuit and Métis people. Hydro One understands that Indigenous Nations have been here since time immemorial and are stewards of what many refer to as Turtle Island. We are all Treaty People and with a commitment to friendship and our pursuit of reconciliation, we are thankful to be welcomed on these lands as partners so we can improve on our past and energize our combined futures.

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