What is the need for this new transmission line?
In Ontario, the Independent Electricity System Operator (IESO) is responsible for
ensuring that future energy needs are being met. According to the IESO, electricity
demand in the southwest region is expected to quadruple by 2035.
To support this growth, the IESO has identified through their long-term planning the
need for the first transmission line to be in-service by 2030. With such significant
demand expected, the Government of Ontario advised Hydro One to concurrently conduct
early development work on the second transmission line while the IESO further assesses
the future energy needs of the region. Pending project approvals, we are focused on starting construction of Line 1 in 2027 to meet the in-service date set by the Independent Electricity Service Operator (IESO). To keep property owners well-informed of the land rights needed for the entirety of the project, we will be securing land rights concurrently for both Line 1 and Line 2.
How was the preferred route selected?
Over the course of the Class EA, we studied each route alternative by collecting data from a variety of sources, such as existing reports and plans, conducting environmental field surveys and technical assessments, as well as engagement opportunities to gather input and feedback.
A weighted multi-criteria decision-making analysis was used to evaluate the alternative routes to select a preferred route. The analysis balanced project-specific criteria in four equally weighted categories: natural environment, socio-economic environment, Indigenous culture, values and land use, and technical and cost. The evaluation concluded that Route 3B ranked highest across all categories and was selected as the preferred route.
Highlights of the preferred route and evaluation results
- The preferred route maximizes the re-use of existing transmission corridors, including approximately 25 kilometres of idle transmission corridor.
- Route 3B is the shortest of the alternative routes and requires the least amount of land for the project.
- The preferred route minimizes impacts on residential properties.
- Compared to all route alternatives, Route 3B involves the least potential disruption to species at risk and their habitats and requires the least vegetation removal, including trees.
I received a letter indicating my property will be affected. How can I get more information?
Now that a preferred route has been selected, the Hydro One Real Estate team will work with directly affected property owners to seek voluntary agreements for the property rights needed to construct and operate the project.
Pending project approvals, we are focused on starting construction of Line 1 in 2027 to meet the 2030 in-service date set by the Independent Electricity Service Operator (IESO). To keep property owners well-informed of the land rights needed for the entirety of the project, we will be securing land rights concurrently for both Line 1 and Line 2.
Please contact us at community.relations@hydroone.com
or 1.877.345.6799 so we can connect you with a representative from our Real Estate team to discuss next steps.
How are the effects on agricultural operations being considered?
Ontario’s farmers are crucial to our economy and reducing impacts on farmland, during and after construction, remains a priority for Hydro One. We’ve had the opportunity to learn about farming operations from other projects we’ve been working on in the region and have incorporated those learnings into our designs for the Longwood to Lakeshore Transmission Line project.
An important part of the EA process involves identifying potential environmental effects of the project, including effects to the socio-economic environment such as agricultural operations, and identifying high-level mitigation measures that could be applied to avoid or minimize these effects. These effects and recommended mitigations will be detailed in our Environmental Study Report which will be released in draft form for public review later this year.
How is public feedback on the draft Environmental Study Report considered?
The draft Environmental Study Report (ESR) is available for a public comment period from September 15, 2025 to October 15, 2025. The report summarizes the Class EA process, which was conducted in accordance with the approved Class EA for Transmission Facilities (2024) under Ontario’s Environmental Assessment Act.
Hydro One values community input and will carefully consider all comments. Hydro One will make best efforts to respond to and resolve issues raised by concerned parties during the review period. Comments and Hydro One’s responses will be documented in the final ESR.
To learn more about the findings from the Class EA process and how to provide feedback, review the draft Environmental Study Report.
