Hundreds of thousands of Ontarians remain in the dark after freezing rain and high winds brought down power lines across the province over the weekend.
For days, crews have worked to clear trees away from downed lines and restore electricity to the more than 850,000 households that lost power as a result of Saturday鈥檚 storm.
By Monday, roughly half of the affected homes had power restored. For those in the hardest hit areas, outages are expected to last for days to come.
It鈥檚 a problem, say some experts, that could be solved by burying Ontario鈥檚 power lines underground.
鈥淚f you鈥檙e getting bad storms frequently, and utilities are becoming a concern, undergrounding is really one of the main options for preventing damage,” said Zeb Tate, associate professor of electrical engineering at the University of Toronto.
Does Ontario use underground power lines?
It鈥檚 more common in dense urban areas, like Toronto, where the city’s power distributor, 海角社区官网Hydro, says nearly half of its power lines 鈥 about 14,000 kilometres worth 鈥 are buried. The practice can minimize physical damage outages, helping to maintain reliable supply to institutions like transit, hospitals, and universities.
鈥淚 would expect very, very little outside of Toronto,鈥 Tate told the Star. 鈥淢aybe one per cent, at most.鈥
In the rest of the province, power is distributed through overhead lines, which are cheaper to install and easier to access if repairs are needed.
Hydro One, for example, which largely serves rural areas of Ontario, relies much more heavily on overhead lines.
Christopher Martins captured the ice storm hitting his neighbourhood Sunday in the north end of Barrie. The city declared a significant weather Saturday night.听
Christopher Martins / FacebookWhy build power lines underground?
The gains of running power lines underground largely come with reliability and safety.
鈥淯ndergrounding is considered one of the primary ways of dealing with extreme weather on a regular basis,鈥 Tate said.
In cases of extreme weather 鈥 such as the recent ice storm 鈥 wiring is less easily damaged if housed underground.
鈥(The) same thing goes for hurricanes, tornadoes 鈥 anything that can just wipe out overhead lines 鈥 they won鈥檛 affect underground lines in the same way,鈥 he continued.
In regions where severe storms are more common, like the coasts, governments may find themselves turning to underground alternatives more readily in the coming years.
Underground wiring is not only “markedly more reliable in delivering uninterrupted electricity,” it鈥檚 also safer, says Jeffrey Feldman, a personal injury lawyer specializing in electrical incidents.
In the last 10 years, Ontario鈥檚 Electrical Safety Authority (ESA)听 there’s been nearly听1,400 incidents of people coming in contact with overhead power lines.
At the same time, power line-related fatalities have been on the rise, says the ESA. Between 2018 and 2022, 12 people died after coming into contact with power lines in Ontario 鈥 a 50 per cent increase from the four years prior.
鈥淏y definition, with underground lines, there can be no overhead contact,鈥 Feldman said, adding that contact with overhead wires is one of the leading causes of electrical injury and death.
鈥淚t just won鈥檛 happen,” he said. “They are not subject to being downed nor are they able to be reached by construction equipment.鈥
Another, perhaps less consequential factor, is esthetics, Tate said.
鈥淪ome people just find overhead lines esthetically displeasing.鈥
Freezing rain, downed trees leave more than 400,000 without power across Ontario following ice storm
- Aliyah Marko, Kristjan Lautens, Anastasia Blosser
What are the downsides?
The most commonly cited barrier, says Tate, is cost; 鈥渋t鈥檚 usually quoted to be about five to 10 times more expensive to install power lines underground.鈥
That was the case in 2014, when former councillor Denzil Minnan-Wong put forth a motion asking city staff to review how much it would cost to convert the remainder of the city鈥檚 power lines underground after an ice storm the year prior knocked out power to around 300,000 homes and saddled the city with a $103-million clean up bill.
At the time, 海角社区官网Hydro CEO Anthony Haines pinned the cost of converting 15,000 kilometres of above ground听power lines at around $15 billion, estimating the move would result in a 300 per cent rate increase for customers.
鈥淭he amount of work required to install them 鈥 to trench or bore the ground 鈥 is just always going to be higher,鈥 Tate said.
While generally less susceptible to damage, underground wires can be harder to access in the event of an outage and the needed repairs are often more extensive.
If those repairs are being done in cities, they inevitably contribute to roadway congestion and ongoing construction as well.
Burying overhead electrical wires would eliminate some blackout risks, but digging up the
Safeguards in place for both, says 海角社区官网Hydro
Overhead or underground, power distribution remains vulnerable to extreme weather, said Lauren Harris, spokesperson for 海角社区官网Hydro.
Floods, like the ones that swept the city last summer, threaten the underground system, while extreme winds, freezing rain, and snow, along with broken trees or collisions, pose risk to overhead lines.
“Extreme weather can cause outages,” Harris wrote in a statement to the Star, “and since the underground and overhead systems are susceptible to different types of extreme weather, burying overhead lines won鈥檛 eliminate outages.”
To address vulnerabilities in both systems, Harris said, “海角社区官网Hydro has a modernization plan to improve resiliency against major disruptions.”
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