In 2003, on behalf of the Cedars Rapids Transmission Company, SEBJ erected a new 230-kV transmission line between Des Cèdres substation in Québec and the City of Cornwall, Ontario. The new line, which covers 29.5 km on the Québec side and 41.5 km in Ontario, was constructed in the right-of-way of a double-circuit line that was built in 1915 and has been dismantled.

For the moment, the transmission line is operating at 120 kV to maintain Cornwall Electric's power supply. The 8.8-km line segment in the City of Cornwall is equipped with reinforced double-circuit towers, to which can be added one or two additional 120-kV circuits when the transmission line is operating at 230 kV.