A new substation to support development in downtown Montréal

Yes, absolutely. Many substations are already located near residential neighbourhoods in Montréal and other cities.

Exposure levels to electric and magnetic fields (EMFs) near substations are low and pose no health risk. In most urban substations, the EMFs measured at the fence surrounding the substation do not exceed the ambient levels measured in any home–which result from the presence of the customer’s service entrance and the daily use of common household appliances.

To learn more, visit the web page on Electric and magnetic fields.

Other impacts:

• Lighting: Only the substation’s main entrance and access road will be lit. At night, the lighting will be directed downward and similar in intensity to street lighting.
• Noise: Outdoor noise will be minimal because all the equipment will be inside the substation building. Indoor substations must comply with noise standards of 40 dB at night (7 p.m. to 7 a.m.) and 45 dB during the day (7 a.m. to 7 p.m.). For reference, 40 dB is equivalent to the noise in a home at night, and 45 dB is equivalent to the sound of a working refrigerator. The standards also state that if noise levels in the area are higher than these cutoffs before the substation is built, those noise levels must be respected after construction.
• Worker traffic after commissioning: Substations are automated, so daily traffic is minimal. Hydro‑Québec will access the substation weekly or as needed for maintenance, with two to three workers present at each time.

Very little literature specifically addresses the impact of substations similar to the one proposed on the market value of neighbouring properties. In general, studies on energy infrastructure indicate that some concerns may exist, particularly regarding visual and noise impacts. However, real estate transactions do not consistently reflect these concerns and when an impact is observed, it often tends to diminish over time.

In this case, the substation will be entirely indoors, which will significantly reduce—or even eliminate—the visual and noise impacts typically associated with this type of infrastructure. Furthermore, to ensure the seamless integration of the planned substation on the site of the former Institut des Sœurs de Miséricorde, Hydro‑Québec is planning exceptional measures, including an architectural competition and the preservation and enhancement of heritage buildings.

These features and commitments aim to promote sustainable coexistence with the host community and to minimize the potential impacts of the planned substation on quality of life and the real estate environment.

Berri and Dorchester substations in downtown Montréal are reaching the end of their service life and must be replaced. The technical constraints and the need to remain at the heart of the area to be served limited the options to a 500‑metre radius. None of the scenarios analyzed met all our criteria.

In spring 2025, Hydro‑Québec took a step back to review the options. This reflection led to the bold approach of broadening the study area and reconfiguring part of the underground system to be able to integrate a substation located farther away.

Of the 19 scenarios assessed, only one met the project requirements: the site of the former Institut des Sœurs de Miséricorde. Located midway between Berri and Dorchester substations, it will allow Hydro‑Québec to efficiently supply both neighbourhoods once the system is reconfigured.

Hydro‑Québec is aware of the need for downtown housing and will work with developers and community stakeholders to promote an affordable housing project.