​​​​

Region Overview

The St. Lawrence Region covers the southeastern part of Ontario bordering the St. Lawrence River. The region starts east of Gananoque and extends to the inter-provincial boundary with Quebec in the East. The western part of the region is supplied by Hydro One-owned stations connected to the 230 kV network. The remainder of the region is supplied from Hydro One stations connected to the 115kV network except for St. Lawrence TS, which is supplied from 230kV.

The City of Cornwall is supplied by Fortis Ontario with transmission lines from Quebec and not included in this Region.

Region's Local Distribution Companies

  • Cooperative Hydro Embrun Inc.

  • Hydro One Networks Inc.

  • Rideau St. Lawrence Distribution Inc.





Map: St. Lawrence


Current Status

The third regional planning cycle for this region was kicked off earlier to align with high-growing electricity demand in the region. The Needs Assessment (NA) report for this region was completed in March 2026. It identified the needs in the region and recommended that some of the needs require further regional coordination, which will be reviewed during the next phases of regional planning.​​

 
Accomplishment (Most Recent Shown First) Status Completion Date
Needs Assessment (3rd Cycle) Completed March 2026
Regional Infrastructure Planning (2nd Cycle) Completed March 2022
Needs Assessment (2nd Cycle) Completed September 2021
Regional Infrastructure Planning Completed July 2016
​Needs Assessment Completed April 2016

*The completed reports are available below.


Relevant Documents

Regional Infrastructure Planning (RIP)
Name Completion Date
St. Lawrence RIP - Report (2nd cycle)  March 2022
St. Lawrence RIP - Report  July 2016
​
Needs Assessment (NA) & Scoping Assessment (SA)
Name Completion Date
St. Lawrence NA – Report (3rd Cycle)  March 2026
St. Lawrence NA – Report (2nd Cycle)  September 2021
St. Lawrence NA – Report  April 2016
​