Live power lines and equipment produce electric and magnetic fields (EMFs). The potential effects of EMFs have been extensively researched for 40 years. Some electrical and electronic devices also emit radio frequencies.

Reservoir creation alters the aquatic environment by transforming and circulating the mercury already present in the flooded vegetation and soil. The result is an initial increase in fish mercury levels, which then return to baseline levels within 10 to 35 years, depending on fish species and reservoir type. This phenomenon is closely monitored and fish consumption recommendations are issued as needed.

Noise emissions from our facilities are a nuisance that we strive to mitigate, particularly in residential areas. We choose quiet equipment when building or updating a facility. If the at-source reduction is insufficient, we take measures to limit noise whenever possible.

Hydro-Québec operations and human health – Current situation
Issue Research Status Conclusion
Health effects of EMFs generated by live conductors and electrical equipment Hundreds of epidemiological studies and tests have been conducted over the past 40 years. The views of certain large organizations are laid out in the brochure entitled The Power System and Health – Electric and Magnetic Fields. To date, no harmful health effects have been found. Hydro-Québec continues to monitor the evolution of knowledge and participate in research carried out elsewhere in the world. In particular, the company is studying the effects of high-intensity magnetic fields on humans as well as high-voltage electric field interference thresholds with regard to the operation of medical implants, including cardiac pacemakers.

Public health authorities in Québec (document in French only) and Canada consider that, within the exposure limits already established, additional protective measures against exposure to EMFs generated by power lines are unnecessary.
Health effects of the temporary increase in fish mercury levels after reservoir impoundment In the late 1970s, Hydro-Québec launched an extensive research program in conjunction with a number of partners. Mercury levels in developed environments are not harmful to fish-eating fish, birds or mammals. However, public health agencies must ensure that anglers do not exceed the mercury exposure level deemed safe for their health.
Health effects of noise from transmission lines and substations The issue of public sensitivity to substation noise is poorly documented. Noise is not spontaneously associated with power lines. Noise generated by lines and substations is relatively limited and cannot cause hearing loss. New substations are designed to meet strict criteria to ensure that the noise produced has no significant effect on the health, activities or behaviour of residents living nearby. The location of new power lines (315 kV and up) takes the level of noise produced into consideration.

Activities in 2016

  • Special edition of the journal Nui Uapaten (in French only) on the topic of mercury in Rivière Romaine along with answers to questions from the Inuit community
  • Financial support to the Natural Sciences and Engineering Research Council of Canada (NSERC) for R&D until 2020. Three lines of research: understanding how mercury dynamics influence the Chute-Allard and Rapides-des-Cœurs developments so as to improve prediction models; studying the influence of climate change on mercury and carbon interactions in boreal aquatic environments; and establishing the relative importance of hydroelectricity in the balance of mercury in the estuary.
  • Contribution to the guide From Tiny Tot to Toddler, to educate new parents about the dangers of electricity use at home
  • Additional trials conducted by the Montreal Heart Institute and the IREQ on a Medtronic Canada Micra™ wireless pacemaker and a subcutaneous defibrillator manufactured by medical device firm Boston Scientific. No interference between electric and magnetic fields and these devices has been recorded.

See also