Pruning near the power systemHydro-Québec corrects information conveyed in a TVA report

Hydro-Québec wishes to correct some of the information presented Michel Morin’s report, broadcast yesterday on TVA, as well as to provide important details.

Considerable expenses
Although the information had been provided to the journalist, he did not include Hydro-Québec’s annual vegetation control budget, which totals some $60 million, a 44% increase since 2003. Here are the annual expenses in this regard for the last 10 years:

• 2003: $42.2 million
• 2004: $42.2 million
• 2005: $42.2 million
• 2006: $42.2 million
• 2007: $48.7 million
• 2008: $50.8 million
• 2009: $54.4 million
• 2010: $59.3 million
• 2011: $60.0 million
• 2012: $60.9 million
• 2013: similar to 2012 – data being compiled

Every year, Hydro-Québec Distribution spends tens of millions of dollars on pruning, clearing and felling work to protect the power system from vegetation growing close to power lines in order to keep the risk of outages to a minimum and to protect workers and the public. This is in addition to the $10 million spent annually by Hydro-Québec TransÉnergie in this sector.

Responsible work planning
Hydro-Québec has approximately 2,400 pruning circuits on a distribution system made up of 110,000 km of lines across Québec. Pruning cycles vary between three and six years, with an average of four years for the province as a whole. Thus every year, vegetation control work is carried out on close to 17,500 km of lines: 65 times the distance between Montréal and Québec. Regions that are especially prone to weather events, such as the Laurentides, Estrie and Montérégie, have their own specific vegetation control program.

More than 800 workers on the job
Hydro-Québec spared no effort to restore service as quickly as possible to its customers affected by the December 22 and 23 outages. More than 800 workers were quickly called in and did a remarkable job in difficult conditions during the holidays. The number of customers affected simultaneously at a given moment reached its peak—53,082—on December 23 at 6 p.m., but in all 405,750 customers experienced outages and 96% had service restored within 24 hours.

Outages associated with vegetation
Falling branches and trees are responsible for almost 40% of power outages. In some more heavily wooded areas, where it is often difficult for crews to reach the system, this proportion can be higher.

For instance, in winter, wet snow and freezing rain significantly increase the weight of tree branches. In spite of pruning, overhanging trees or branches can give way and fall on the lines, causing major damage. In summer, strong winds are often responsible for bringing vegetation into contact with the system, as was the case during the outages in Laval in July 2013, when trees that were not close to the power system were uprooted and caused damage.

In short, notwithstanding rigorous vegetation control work, it is impossible for Hydro-Québec, or any other power distributor, to prevent all vegetation-related outages. Hydro-Québec’s system is robust and reliable. However, it is not immune to the vagaries of weather—strong winds, freezing rain, storms or other events—that can cause outages and damage equipment.

To find out more about vegetation control, click here.

For information:

Patrice Lavoie
Hydro-Québec
514 289-2097
lavoie.patrice2@hydro.qc.ca