hree months before the biggest blackout in North
American history, the agency charged with protecting the nation's
electrical grid put industry officials on notice that the section of
the grid covering Ohio and other parts of the Midwest was
particularly vulnerable to the kind of "cascading events" that
unfolded last Thursday.
Officials with the group, the North American Electric Reliability
Council, in a report that singled out the Midwest as the only part
of the country at risk of such a devastating event, said the region
could face "large, unanticipated power flows" this summer and would
have to be prepared to handle the challenges with care.
Officials at the reliability council, an industry group, lacked
the authority to order the utilities to take additional steps to
prevent a small local failure from snowballing into a catastrophic
one. And they concede that they did not even informally suggest
anything more be done to protect that section of the nation's
fragile grid. But the report makes it clear that the industry had
been notified of the threat in the region and the fine margin for
error that existed.
That margin for error, many experts now say they believe,
disappeared last Thursday afternoon after several power lines went
down in Ohio. That was the beginning of a blackout that ultimately
extended from Detroit to Toronto to New York, they say. While
investigators say they have weeks of work to do before understanding
the precise causes and chronology of the electrical collapse, the
failures of Midwestern transmission lines and power plants and the
warning system meant to limit the spread of trouble are considered
Officials at the FirstEnergy
Corporation, the company responsible for the lines that
started failing before any widespread blackout, declined yesterday
to comment on the report and to say whether the company had taken
any steps in response to the warning.
Energy officials and other experts say the existence of the
report makes it all the more critical for investigators to determine
whether the region's utilities, having received such an explicit
reminder about their obligations, followed the proper protocols and
met those challenges on that day.
Officials with the reliability council confirmed that the mention
of potential cascading power failures in the region was a
significant warning. "Our reliability assessments don't mention
problems lightly," said Ellen Vancko, a spokeswoman for the group,
created after the 1965 blackout to prevent such calamities.
Since the deregulation of the energy industry, the section of the
Midwest grid identified in the report has become one of the great
crossroads in the transmission of power across the nation — a kind
of Times Square in the flow of electrical traffic. Power produced as
far away as Denver flows through the Midwestern grid on its way to
users in New York and elsewhere.
The assessment by the reliability council, issued in May, would
have been seen by virtually all controllers of the grid nationwide,
said Mary Lynn Webster, a spokeswoman for the Midwest Independent
"Anyone in grid management in the United States would be looking
at it," Ms. Webster said.
The Midwest Independent System Operator is charged with helping
oversee the safe generation and transmission of power in the Ohio
area, although responsibility for taking action in a crisis rests
with individual utilities.
Ms. Webster said that as the report suggested, this part of the
grid was susceptible to "unanticipated flows because of something
that is happening somewhere else on the system," like commercial
transactions between companies outside the region that nevertheless
pour electricity through its boundaries.
Those conditions can also be caused by an unexpected power
failure or a generating unit that breaks down on the local grid, she
said. But she cautioned against assuming that this was the only part
of the national grid that was prone to those conditions. "There are
areas in all parts of the country that are constrained," Ms. Webster