This project is subject to the Ontario Environmental Assessment (EA) Act in accordance with the Class EA for Minor Transmission Facilities. The Class EA process is an effective way of ensuring that transmission projects that have a predictable range of effects are planned and carried out in a manner which is environmentally acceptable. The Class EA study will investigate alternative methods and options to refurbish the transmission infrastructure. The existing corridor between Leaside TS near Millwood Road/Laird Drive, and Birch Junction (Jct) near Yonge Street./Summerhill Avenue will be considered as one potential route. In addition, other alternative underground cable routes will also be identified and evaluated as part of the EA process. Other associated work at Bridgman, Birch and Bayview Jct, and Leaside TS will also be required.

Following a consultation process with members of the public, government agencies and municipalities, a draft Environmental Study Report (ESR) is made available for stakeholder review and comment for a review period, and the details of the public review process are advertised in local newspapers.

If no concerns are expressed during the review period, the project is considered to be acceptable. The final ESR is filed with the Ministry of the Environment.

If concerns are expressed during the review period, Hydro One will attempt to resolve them to complete the EA process. If Hydro One cannot satisfy all of the concerns, a stakeholder may submit a "bump-up" request for an individual Environmental Assessment of the proposed undertaking. Hydro One will then consider whether a re-designation of the project is appropriate, and send its response, the draft ESR and the individual's bump-up request to the Minister of the Environment for a decision as to whether or not the project requires an Individual EA or if the project should be approved as proposed.

Hydro One released its Draft Environmental Study Report (ESR) for a 45-day public review period beginning March 8, 2010.  Read the Notice of Completion for details on this process. No Part II Order requests were received. On June 30, 2010, Hydro One filed the final ESR with the Ministry of the Environment. Hydro One will proceed with the proposed undertaking outlined in the report. Download the final report:

On June 30, 2010, Hydro One filed the final ESR with the Ministry of the Environment. Hydro One will proceed with the proposed undertaking outlined in the report. Download the final report:


The Midtown Project is also subject to Ontario Energy Board (OEB) Leave to Construct (Section 92) approval. The OEB regulates Ontario's natural gas and electricity industry and will determine whether the construction and operation of the proposed facilitates are in the public interest. The OEB approval process also includes opportunities for public and stakeholder involvement.

On September 12, 2006 Hydro One submitted a Transmission Revenue Requirement and Rate Application for 2007 and 2008 to the OEB. In this application, Hydro One requested that the OEB approve the need for infrastructure refurbishments from Leaside TS to Birch Jct. To read this application, visit our Regulatory Affairs section.

In mid-November 2006, the OEB published a Notice of Application (reference EB-2006-0501) in newspapers across Ontario, including community newspapers serving the midtown Toronto area and the Toronto Star. This notice include specific reference to the Leaside TS to Birch Jct infrastructure refurbishment. The decision on this application was released by the OEB on April 3, 2007. It stated that Hydro One had provided sufficient evidence to confirm that there is need to relieve load on the existing 115kV cables running from Leaside TS to Birch Jct. The OEB also indicated that issues regarding route options, alternatives and cost will be examined in separate Section 92 applications to the OEB, as outlined above.

On December 23, 2009, Hydro One submitted an application to the Ontario Energy Board (OEB) pursuant to Section 92 of the OEB Act, 1998, seeking "leave to construct" for this project. The application has been assigned file # EB-2009-0425 and is entitled Toronto Midtown Transmission Reinforcement Project. On June 17, 2010, The OEB  found the project to be in the public interest in regard to its impact on price, reliability and quality of electricity service to consumers, and approved this application with conditions. Read the decision here.

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