TORONTO — At 4:11 p.m. on Aug. 14, 2003, the system supervisor in the control room overseeing Ontario's electrical grid saw four alarms pop up on his computer screen.
Then came 30,000 more.
"It looks like we've had a disturbance," Todd Parcey recalls saying, in what proved to be a massive understatement.
He didn't know at the time that problems in Ohio had caused 50 million people to lose power in the northeastern United States and Ontario. That included the entire province east of Wawa except for small pockets in the Niagara and Cornwall areas. It was the worst blackout in North American history.
The 30,000 alarms, however, and their accompanying noises and visuals were a pretty good clue of the scale of the "disturbance."
"It's very comparable to someone winning the jackpot in a casino or walking into casino and hearing all the noises, but every noise actually means something to you," Parcey says 20 years later.
"My desk itself has 11 computer monitors on it and one of them is dedicated just to alarms. So (when you hear) that initial 'gong,' you look over at your alarm screen. I recognized the first four or five alarms and then everything just scrolled right off the page."
Outside the Independent Electricity System Operator (IESO) control room that day, most people in the province were dealing with their own disturbances — walking home for hours because the subway in Toronto was shut down, ordinary citizens volunteering to direct traffic with no signals to guide drivers, and neighbours barbecuing and sharing fridge cleanout meals by candlelight.
Investigations would later determine that a series of failures in Ohio triggered the blackout. A system monitoring tool was not working, then a generating unit tripped off in an overloaded portion of the grid, and then overheated transmission lines began sagging into overgrown trees and tripping.
By the time officials realized the system was in jeopardy, it was too late to intervene and the collapse sent unsustainable loads into neighbouring jurisdictions.
In Ontario, the IESO says a series of large power swings pulsed into the province's grid interconnections at Michigan and New York.
David Robitaille, now a senior director of market operations at the IESO, had just landed at Toronto's Pearson airport when the power went off.
He had been in New Jersey, working with colleagues from other jurisdictions that are part of the North American Electric Reliability Corporation (NERC), which sets electricity standards to ensure functionality and security of the power grid.
Ironically, Robitaille had been working on developing the NERC's first set of grid standards.
After landing, he had to disembark the plane away from the gate and sensed there was trouble. The chaos at customs proved he was right.
At the IESO, Parcey and his team took a minuteto shake off the initial confusion before setting about getting the grid back on track.
"We train for this sort of thing constantly," he says. "You take your pause for a second and then (say) 'OK, what do we have left?' and then try to understand the scope of the event, and then we're trying to stabilize what's left. Once that's stabilized, then basically our next task is start to restore off-grid power to the nuclear plants."
The IESO doesn't directly turn switches on and off, but the act of grid restoration involves co-ordinating with power generators and companies like Hydro One that operate the transmission lines.
"The job is very similar to air traffic control, but we do it for electricity," Parcey says.
On Aug. 14, 2003, IESO staff were on a bank of six phones for about 20 hours straight — trading off in shifts of four hours — giving those instructions, Parcey recalls.
The nuclear plants can run indefinitely without that off-site power or can just shut down into safe mode, Parcey said, so safety wasn't the main concern, but they provide a large percentage of Ontario's electricity generation.
To open up a transmission path from that pocket of generation in Niagara Falls up to the Bruce Power nuclear complex, for example, it's a delicate balancing act energizing circuits and adding some load if the voltage starts to increase too much.
"It's one step after another," Parcey says. "You take baby steps until you get to a point where you have enough connected that you can take larger steps."
The grid's 18,000 kilometres of transmission lines were restored by midnight and most customers had power back the next day.
Many Ontarians heeded officials' calls to reduce their electricity consumption for the next week in order to assist with recovery efforts and Parcey says that helped tremendously.
All told, there was a net loss of 18.9 million work hours, and manufacturing shipments in Ontario were down $2.3 billion that August, according to a report by the U.S.-Canada Power System Outage Task Force.
But most will likely remember the day for the unique moments it sparked among co-workers, neighbours or complete strangers.
"Listening to a lot of the stories afterwards, it was very Canadian experience," Parcey says. "I think people really came together."
Ontario's current energy minister, Todd Smith, was anews director for a radio station in Belleville, Ont., in August 2003.
After working the morning shift, he was golfing with friends when word got out the power for the entire eastern seaboard had shut down.
“I then quickly jumped in my car and headed into the radio station,” he recalled.
When he arrived at the station, he realized the blackout was far bigger than a local story.
“It was just very surreal to see every traffic light out, and not just in places like Belleville and Trenton, but right across the province and a large portion of North America," he said.
Smith, who was elected as a Progressive Conservative MPP for Bay of Quinte in 2011, said Ontario learned from the blackout and has since become a leading advocate for grid standards.
Robitaille, of the NERC, agrees that "the resilience of the system is much better now than what it once was," noting that the NERC standards have been established with audits held every three years.
But, Smith warned, "we can't take reliability for granted."
“Every time I fly over the waterfront in Toronto at night and I see all the lights that are on in all of the buildings, I certainly think about the responsibility that we have for those of us who work in the energy sector."
This report by The Canadian Press was first published Aug. 12, 2023.
--With files from Liam Casey and William Eltherington
Allison Jones, The Canadian Press
