Submitted by BC Hydro

A new BC Hydro report outlines how drought-weakened trees coupled with stormier La Niña weather conditions may result in more power outages this fall and winter.

In the report titled, “The perfect storm: How summer drought could mean severe fall storm fallout,” BC Hydro meteorologists predict this summer’s record-breaking temperatures in B.C. could mean a fresh accumulation of dead and weakened trees that could be a risk to electrical infrastructure. La Niña is predicted to bring colder, wetter and windier weather to the west coast this fall and winter. The inclement weather coupled with drought-weakened trees could result in the ‘perfect storm’ for outages.

Summer 2021 was the hottest summer on record in most parts of B.C and resulted in severe drought – weakening tree roots, wood and soil and leaving them more susceptible to failure. Prolonged drought can make trees more susceptible to dehydration and pathogens such as insects or fungi, leading to higher mortality rates. There are also the issues of weakened root structure and soil-loss of fine root structure due to drought makes trees more susceptible to uprooting, and dry soil is more rigid and acts as less of a shock absorber when the wind hits. On top of this, dry wood is more brittle with less flexibility to bend or stretch as the wind passes through–meaning greater susceptibility to tree failures.
BC Hydro’s two most damaging storms were caused by a drought in the summer of 2015 and a drought followed by unseasonably heavy rainfall in 2018. The 2015 summer storm caused over 710,000 outages and lasted multiple days.

Much like 2015, B.C. saw less precipitation in most regions this summer. Abbotsford, Vancouver and Comox had some of the driest conditions from April to July – with Abbotsford experiencing the lowest rainfall recorded in the Fraser Valley in more than 60 years.

BC Hydro is increasing its vegetation management program this year given the drought and weather-related challenges. British Columbia has some of the highest densities of trees per kilometre of power line compared with most jurisdictions in North America. Trees and adverse weather are the single biggest cause of power outages in B.C.

BC Hydro is advising customers to prepare for what could be a challenging storm season. It is important for customers to be prepared by having a well-stocked emergency kit that includes:
• flashlight,
• extra batteries,
• first aid kit,
• non-perishable food and
• water.
Despite increasing storms, the duration of power outages for BC Hydro customers has been on the decline and is currently below the five-year average. Power service is restored for most customers within the first few hours of an outage.

BC Hydro is also reminding the public that if they come across a downed or damaged power line, assume the line is live, stay back at least 10 metres (the length of a city bus), and call 9-1-1 to report. For more information on outages and safety, visit bchydro.com/outages.