Hydro One says it's investing $35 million to upgrade the Rabbit Lake substation.
Work has been going on for several month to upgrade breakers, switches and insulators.
As well, new equipment is being installed.
To complete the work, there will be a power interruption on October 1st, lasting several hours.
This will include the whole City of Kenora which is serviced by Synergy North.
The outage will take from 6 in the morning until 2:00 in the afternoon on Sunday, which Synergy North says is a time of least electricity usage.
