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The Great Northeast Blackout of 2003


At 12:15 in the afternoon on Thursday, August 14, 2003, a seemingly routine procedure enacted by the Midwest Independent Transmission System Operator set into motion a chain of events that would affect 55 million people in the Northeastern United States and Canada. The Great Northeast Blackout of 2003 caused the failure of more than 508 generating units at 265 separate power plants, causing almost one in every six people in the United States to lose power for up to 2 days. The blackout demonstrated the interconnected nature of the North American infrastructure, and its vulnerability to small and relatively benign problems.



Because it is not economical to store electrical power over long periods of time, electricity is generally produced as it is needed, and consumed immediately after being produced. System operators are therefore needed at power generating stations to balance the load on a given power grid, and prevent overloads of power lines and generators. These operators monitor the electrical grid via computer systems, which alert them when overloads and faults occur.

If a fault occurs somewhere in an individual transmission line, other transmission lines automatically compensate for the change in the flow of electrical current. If the other transmission lines do not have the spare capacity to handle the increased electrical flow, however, they too become overloaded and shut themselves down, causing what is known as a cascading failure of the electrical grid. In such instances, operators will typically cut power to some areas in their grid in order to isolate the failure and bring the system back into balance.

New York City skyline during the blackout

New York City skyline during the blackout

The Blackout Begins

At 12:15PM, the power flow monitoring tool at the Midwest Independent Transmission System Operator shut itself down due to incorrect telemetry data. A technician corrected the issue that was causing the incorrect data, but then mistakenly forgot to restart the monitoring tool. Because of this, the FirstEnergy power plant in Eastlake, Ohio, was not notified of a spike in its power load, and shut itself down a little over an hour later. Transmission lines all over northeast Ohio began to sag and come into contact with trees, causing them to transfer their current irregularly and fail. In a bad stroke of luck, FirstEnergy's control room was not notified of the failing lines due to a rare computer bug known as a race condition, which delayed their alarm system from signaling the problem for over an hour.

In a matter of two hours from the initial failures, circuit breakers connecting FirstEnergy's grid with that of neighboring power grids began to trip. For some reason, FirstEnergy operators failed to notify operators in neighboring states, and their grids began to become overloaded as well. By 4:00 in the afternoon, the transmission line failures were spreading like wildfire, moving into Pennsylvania, New York, Michigan, Ontario, and New Jersey. The cascading failure was finally contained at 4:13PM, when Northern New Jersey separated its power grids from the New York and the Philadelphia areas, stopping the spreading outages in their tracks. If this action had not been taken, there is no telling how far the blackout would have spread.

Pedestrians traveling by foot over the Brooklyn Bridge

Pedestrians traveling by foot over the Brooklyn Bridge

The Nightmarish Afternoon Commute

With the power out from Ontario down through Northern New Jersey and as far west as Ohio, many people leaving work in the afternoon were met with sheer gridlock, as traffic lights were out at almost every intersection. The nexus of the nightmare was definitely New York City, where the failure of subways and trains left millions of people with no choice but to walk or take non-electric vehicles out of the city. For the entire evening, the bridges, tunnels, and highways throughout the metropolitan area were jam-packed with pedestrians electing to use the faster option of walking. Reports abounded of many buses taking four hours just to get out of the borough of Manhattan. Those whose commute was simply too far to walk were left stranded in New York, and were forced to sleep in parks and on the steps of public buildings.

AMTRAK and New Jersey Transit rail service along the Northeast Corridor, which is used by millions of commuters every day, was also shut down at North Jersey. Those who lived in the blacked-out areas had to take the train as far as they could get, and then call friends or family members to come and pick them up and take them the rest of the way to their homes. People traveling by air fared no better. Almost all of the region's airports were shut down due to the inability to properly conduct passenger screenings. Flights were cancelled across the Northeast well into the day on Friday.

Twilight on Fifth Avenue during the blackout

Twilight on Fifth Avenue during the blackout

Fears of Unrest

As it became clear that power was not going to be fully restored by the time night fell, the specter of the infamous 1977 blackout hung over New York City. The previous blackout was characterized by massive amounts of looting, vandalism, and arson, and served as a black eye for the city for many years to come. However, the fears turned out to be unfounded. Many restaurants and bars prepared their food that was going to spoil and passed it out to anyone who came by free of charge. The atmosphere in the city became festive, with block parties sprouting up in almost every neighborhood. Thursday night passed largely without incident.

Power is Restored

It was late into the evening of the 14th that the electrical grid began to come back online in its outlying locations, such as Ontario and New Jersey. New York City began to come back online early in the morning on Friday. By Saturday afternoon, almost all of the affected population had their power restored, though some individual substations found themselves experiencing problems unrelated to the initial blackout, causing some customers to have to wait several more days for the lights to come back on.

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The Aftermath

The northeast by and large handled the loss of power in stride. There were only scattered reports of criminal mischief during the crisis, although there were many reports of fires linked to the careless use of candles as a light source. The lack of disorder in the affected areas during the nighttime hours was an encouraging sign to law enforcement and homeland security officials.

The bulk of the blame for the blackout fell on the shoulders of FirstEnergy, who had failed to notify operators of adjacent power grids about the events they were experiencing, and instead focused all of their efforts on trying to understand what exactly was happening. A joint U.S.-Canada Power System Outage Task Force put together to investigate the blackout found that the utility "failed to assess and understand the inadequacies" of their system, that they "did not recognize or understand the deteriorating condition" of their system, and that they "failed to manage adequately tree growth in its transmission rights-of-way".

The Great Northeast Blackout of 2003 ultimately demonstrated the sensitivity and interconnected nature of the electrical infrastructure in North America, and how vulnerable it was to systematic failures. The incident caused many government officials and political pundits to openly speculate about how the nature of the electrical grid might be exploited for nefarious purposes. To date, however, no major upgrades have been made to the infrastructure to address these issues.


Zak Brown on December 21, 2012:

This is more detailed than Time Mag. Awesome :-D

Matt Weeks (author) from Burlington, NJ on November 02, 2011:


I would appreciate that very much. Thank you.

ThoughtSandwiches from Reno, Nevada on November 02, 2011:


I recall when this went down and this wonderful Hub has provided far more useful information then any reporting at the time!

The picture of the blacked out area is very eerie. So...three cheers for New Jersey, huh? (I honestly never believed I would ever type that).

Excellent job Matt. If it is alright with you I would like to link to this Hub in the future? I believe I will also share on Facebook. Thanks for the read!


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