On the calendar
August 14, 2003 was a Thursday, the 226th day of 2003 with 139 days left in the year. It fell in ISO week 33.
The Northeast blackout of 2003 began just after 4:10 p.m. Eastern time on Thursday, August 14, 2003, when a chain of failures that started in northern Ohio collapsed much of the power grid in the northeastern United States and Ontario. About 50 million people lost electricity, from Detroit and Cleveland to New York City and southern Ontario. US and Canadian officials later called it the worst blackout in North American history.
What Happened on August 14, 2003
The trouble built for about two hours before the lights went out. Early that afternoon, transmission lines in northern Ohio began dropping out of service. At 3:05 p.m., FirstEnergy’s Harding-Chamberlin 345-kilovolt line sagged into a tree and shut off, and more lines followed.
Inside FirstEnergy’s control room, operators did not see the danger. A software flaw had stopped the alarm system in its energy management computers from working, so the warnings that should have flagged each failure never appeared.
Shortly after 4:10 p.m., the failures cascaded. Within minutes, transmission lines and power plants across the region tripped off, and the outage spread through Michigan, Ohio, Pennsylvania, New York, New Jersey, parts of New England and Ontario. Over the course of the event, 508 generating units at 265 power plants shut down, and about 61,800 megawatts of electric load was lost.
Timeline of August 14-18, 2003
| Date and time (EDT) | Event |
|---|---|
| August 14, 2:02 p.m. | A 345-kilovolt line in Ohio trips, one of the first failures of the afternoon |
| August 14, 3:05 p.m. | FirstEnergy’s Harding-Chamberlin line sags into a tree and shuts off |
| August 14, 4:10 p.m. | The cascade spreads; New York’s grid operator logs a power surge at 4:10:39 |
| August 14, about 8 p.m. | Limited New York City subway service resumes |
| August 16 | Power is fully restored in New York City |
| August 18 | Detroit lifts its boil-water advisory |
Life Without Power
The blackout struck as the evening rush hour was beginning.
In New York City, more than 600 subway and commuter rail cars were stranded between stations, and all passengers were evacuated without serious injury. Limited subway service resumed around 8 p.m., but full service took until Saturday morning.
Water systems that relied on electric pumps lost pressure. Detroit placed its roughly 4 million water customers in eight counties under a boil-water advisory that lasted until August 18, and Cleveland issued a similar advisory after its pressure dropped.
Restoration was uneven. Some areas had electricity back that evening, while New York City was not fully restored until August 16. Parts of the United States went as long as four days without power.
Why the Grid Failed
The US and Canadian governments formed a joint US-Canada Power System Outage Task Force to investigate. Its final report, released in Ottawa on April 5, 2004, by US Energy Secretary Spencer Abraham and Canadian Natural Resources Minister R. John Efford, grouped the causes into four areas:
- Inadequate system understanding. FirstEnergy and its reliability council had not recognized weaknesses in the northern Ohio system, including a shortage of reactive power, the support that keeps voltage stable, that had existed for several years.
- Inadequate situational awareness. Operators did not know their alarm system had failed and did not grasp what was happening on their own network.
- Inadequate tree trimming. Lines sagged into trees that had been allowed to grow too close.
- Inadequate diagnostic support from reliability coordinators. The regional overseers did not provide real-time help when the situation deteriorated.
The task force also identified seven violations of the reliability standards then administered by the North American Electric Reliability Council. Those standards were voluntary.
How the 2003 Blackout Changed the Power Grid
The task force’s first recommendation was to make reliability standards mandatory and enforceable, with penalties for violations. Congress acted in the Energy Policy Act of 2005, which added a new section to the Federal Power Act giving the Federal Energy Regulatory Commission authority to approve and enforce grid reliability rules through a national Electric Reliability Organization.
On July 20, 2006, FERC certified the North American Electric Reliability Corporation, the successor to the old council, as that organization. Its standards became mandatory and enforceable in the United States on June 18, 2007, nearly four years after the blackout.
Other recommendations called for a regulator-approved funding mechanism to keep NERC and the regional councils independent of the utilities they oversee, fixes to the deficiencies found at FirstEnergy and some reliability organizations by June 30, 2004, better operator training and certification, and stronger physical and cyber security for the grid. Abraham called the recommendations “a roadmap for solving this critical international challenge.”
Remembering the Date
The full 2003 calendar shows that the outage fell on a Thursday in mid-August, and the day-of-the-week tool can confirm the weekday of any related date. Times in the official reports are given in Eastern Daylight Time; the guide to US time zones explains how that compares with other regions. The policy changes it produced appear on the 2005 calendar and 2007 calendar.
Frequently asked questions
What caused the 2003 Northeast blackout?
The blackout began in northern Ohio on FirstEnergy's system. High-voltage lines sagged into overgrown trees and shut off, while a software failure disabled the alarm system in FirstEnergy's control room, so operators did not see the problem growing. The US-Canada task force grouped the causes as inadequate system understanding, situational awareness, tree trimming and reliability coordinator support.
How many people lost power in the 2003 blackout?
About 50 million people lost power, according to the US-Canada Power System Outage Task Force. The outage covered parts of Ohio, Michigan, Pennsylvania, New York, New Jersey and several New England states, along with much of southern and central Ontario, and removed about 61,800 megawatts of electric load from the grid.
How long did the 2003 blackout last?
It varied by place. Some areas had power back the same evening, but restoration took much longer elsewhere. New York City's power was fully restored on August 16, and some parts of the United States went as long as four days without electricity. Detroit's water customers stayed under a boil-water advisory until August 18.
What changed after the 2003 blackout?
Investigators found that the grid's reliability rules were voluntary and that several had been violated. The Energy Policy Act of 2005 made reliability standards mandatory and enforceable, and in July 2006 federal regulators certified the North American Electric Reliability Corporation as the national Electric Reliability Organization. Its standards became enforceable in the United States in June 2007.
Sources
- U.S.-Canada Task Force Presents Final Report on Blackout of August 2003 - US Department of Energy
- Final Report on the August 14, 2003 Blackout in the United States and Canada - Lawrence Berkeley National Laboratory
- Canada-U.S. Task Force Presents Final Report on Blackout of August 2003 - Government of Canada
- Progress on preventing blackouts - The Christian Science Monitor
- Northeast blackout of 2003 - Wikipedia
Facts in this article were checked against the sources above. See our editorial policy to report a correction.