To ensure that service is reliable and its facilities are safe, Hydro-Québec must control the vegetation in its transmission and distribution line rights-of-way and on dikes and dams. Environmental considerations are incorporated into all vegetation control operations. For example, long-term results show that mechanical treatment with rational use of herbicides promotes biodiversity [PDF 6.4 Mb – in French only] and the growth and maintenance of compatible vegetation in transmission line rights-of-way. No herbicides are used in distribution system maintenance.

For the past five years, we have been using Light Detection And Ranging (LIDAR) technology to compare ground cover height with conductor height in order to determine what operations are required to control vegetation growing in line rights-of-way. The gradual optimization of vegetation inspection in rights-of-way will also maintain system reliability through improved knowledge of the minimum clearances that are safe for the public, workers and the system.

Video: Distribution system vegetation control

For the safety of the public and workers, and to prevent outages and ensure reliable system operation, Hydro-Québec controls vegetation around distribution system power lines. Clearing is done in an environmentally responsible manner and preserves biodiversity near the lines. Vegetation control operations are planned by Hydro-Québec's forest engineers and technicians, and carried out by qualified contractors.

2017 HIGHLIGHTS

  • Meetings were held with municipal and MRC representatives to discuss vegetation control near transmission and distribution lines. The meetings gave us a chance to receive feedback as well as equip local representatives to address questions from residents.
  • We tested a light, collapsible drone to monitor vegetation control operations in transmission line rights-of-way. The drone could help optimize the inspection of hard-to-reach power lines.

Vegetation control along transmission line rights-of-way

The table shows the areas treated mechanically, those treated selectively with herbicides and the total area treated. The percentage between areas treated mechanically and the total area treated is then indicated.

In 2017, the total area of transmission line rights-of-way was 176,745 ha. The area treated increased by 5,893 ha compared to 2016, with 5,284 more hectares treated mechanically and 609 more hectares treated selectively with herbicides. The percentage of work carried out mechanically has remained relatively stable over the years.

Vegetation control along dikes and dams

The table shows the areas treated mechanically, those treated selectively with herbicides and the total area treated. The percentage between areas treated mechanically and the total area treated is then indicated.

Herbicide use and mechanical treatment follow a five-year vegetation-control planning cycle and thus vary from year to year. The proportion of herbicides used also changes annually.