By David Morgan
NEW YORK, Aug 16 (Reuters) - Life returned to normal on Saturday for millions caught in the worst blackout in North American history, but isolated outages stubbornly continued in communities from Michigan to Connecticut and Ontario, Canada.
Two days after cascading outages blackened an area of more than 9,000 square miles (23,310.000 sq km), a U.S.-Canadian task force searched for a cause while public officials across the region tried to assess the financial cost.
In New York City, where full power returned late on Friday after 29 hours, subway trains began running again while stores and restaurants opened for what they hoped would be their first normal day since the lights went out on Thursday afternoon.
But public officials remained cautious, urging residents to conserve energy by keeping lights, air-conditioners, washing machines and other electric appliances turned off.
Airports continued to report flight delays due to lingering computer problems, while thousands of stranded air travelers lined up in the hope of booking new flights out of John F. Kennedy, LaGuardia and Newark Liberty airports.
New York Gov. George Pataki said full electric service resumed across the state on Saturday. But he kept a state of emergency declaration in place, warning that the in-state power grid was operating at 43 percent below full capacity.
"We're still in a delicate balance between what we can generate and the demands on the utility grid," Pataki told a news conference in Albany, New York.
The governors of New York, New Jersey and Connecticut were due to mee later on Saturday with U.S. Energy Secretary Spencer Abraham in the hope of getting assurance that steps would be taken to prevent outages from recurring.
"As of now, I can tell you that we still don't know, and I don't know that anyone in Washington or Ottawa or anywhere else knows, why this happened," Pataki said.
"We need to know that steps are being taken to prevent this from happening again," he added.
SPORADIC OUTAGES
Residents of Cleveland, Ohio, were boiling their drinking water after the blackout paralyzed the area's water pumps. But water service returned to all but a few isolated areas with broken mains.
"Everyone should have water to their house unless there's been some sort of mechanical problem," Cleveland Mayor Jane Campbell told Fox News.
Full electricity service returned on Saturday morning to the city of Detroit, raising the prospect that the Big Three automakers would avoid production shortages despite the shutdown of dozens of plants and offices.
But sporadic outages continued in isolated sections of Connecticut and New Jersey, while in Ontario, officials warned of possible rolling blackouts as utility authorities worked to stabilize the region's power grid.
The outage that plunged an estimated 50 million people into darkness on Thursday eclipsed major blackouts that paralyzed the eastern cities in 1965 and in 1977. Both times, stricken communities were assured that a similar crisis would not happen again.
"After the last blackout, they created the North American Electric Reliability Council. If ever there was a misnomer, it's the 'electric reliability council.' We did not have reliability," Pataki said.
On Friday, the White House announced that a cross-border task force would investigate the massive blackout following talks between U.S. President George W. Bush and Canadian Prime Minister Jean Chretien.
Chretien had suggested earlier that the cause of the power collapse lay in the United States, but some U.S. utility officials insisted the problem started in Canada.