Their environmental impacts

Power transmission systems often have to pass over farms to bring power to consumers in load centers. Many studies have investigated the biological effects of electric and magnetic fields on plants and animals.

  • Vegetation

    The effects of magnetic and electric fields on plant life has been studied in the field, in greenhouses and in the laboratory. On the whole, the findings of these studies show that plant life is not affected by electric and magnetic fields, except for some drying out (browning) of leaves with pointed tips in very high electric fields. In addition, the quality of vegetables that grow under high-voltage lines is not affected.

    Close-up of a cabbage growing in a garden under power lines.
  • Bees

    Transmission line rights-of-way are home to hundreds of indigenous bee species. Generally solitary, bees nest in the ground or in woody material, while bumblebees are social and commonly nest underground, in existing cavities. Transmission line rights-of-way do not pose any danger to bees or bumblebees.

    Still, the electric field generated by high‑voltage lines can be a serious disturbance to honey bees (Apis mellifera) by inducing weak currents in their bodies through the discharge of small intermittent or continuous electric shocks when the bees come in contact with conductive objects such as the hive. These biological effects of the electric and magnetic fields (EMFs) impact the bees’ behavior. Experiments in the lab and under high-voltage lines have shown that EMFs and electric shocks within the hive affect the bees’ physiology, life expectancy and social habits, as well as honey production. That’s why it is prohibited to set up hives near transmission line rights‑of‑way.

    Close-up of a bee gathering pollen from a daisy.
  • Livestock

    A number of studies have been conducted to determine if electric and magnetic fields generated by high‑voltage lines can affect the health, productivity, fertility, reproduction or behavior of livestock. These included investigations, database analyses and extreme case studies and were carried out on cattle, pigs, sheep and horses. The findings of this research seem to indicate that no biological disorders can be attributed to livestock exposure to fields generated by high-voltage lines. No harmful effects on the health, productivity, fertility, reproduction or behavior of livestock exposed to electric and magnetic fields were observed.

    Herd of cows grazing grass in a field.

Publications

Hydro‑Québec research publications from 1988 to 2020

Other studies across the globe on effects of electric and magnetic fields on livestock

Studies on the effects of electric and magnetic fields in livestock