Today marks 20 years since North America blackout left 50M without power

Monday marks 20 years since the largest power outage in North American history left 50 million people across Ontario and the northeastern U.S. in the dark.

It was 4:11 p.m. on August 14, 2003 when the Ontario electrical grid system supervisor saw four alarms pop up on the screen.

Those four would soon be followed by 30,000 more.

Fifty million people would lose power in the northeastern United States and Ontario, with only small pockets in Niagara and Cornwall holding onto power.

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The blackout would leave people throughout the province coping with the outage with some spending hours walking home with Toronto subways down, ordinary citizens directing traffic and neighbours barbecuing and sharing fridge cleanout meals by candlelight.

Investigation would later reveal that a series of failures in Ohio triggered the blackout. It began with a system monitoring tool not working, followed by a generating unit tripped off in an overload portion of the grid and culminated in overheated transmission lines sagging into overgrown trees and tripping.

By the time officials realized the state of the failures, it was too late and the collapse would send unsustainable loads into neighbouring areas.

In Ontario, the Independent Electricity System Operator (IESO) says a series of large power swings pulsed into the province’s grid interconnections in Michigan and New York.

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Grid restoration would involve a coordinated effort between IESO power generators and power companies like Hydro One that operate transmission lines themselves.

On that day in 2003, ISEO staff would be on a bank of six phones for 20 hours straight while trading off in 4 hour shifts coordinating those efforts.

Ultimately, 8.9 million work hours would be lost 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.

Most, though, will recall the day for the unique moments and memories it sparked between co-workers, neighbours, friends, family or even complete strangers.

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