A man walks past a downed power line in the aftermath of Hurricane Irene in Nassau, on New Providence Island in the Bahamas, Aug. 25, 2011. / AP
NEW YORK - Hurricane Irene's strong winds and heavy rains threaten to deliver long-lasting power outages to millions of customers along the East Coast, utility officials and weather forecasters say.
An unusually large number of people may be affected by Irene because it is forecast to stay just offshore and thus retain much of its power as it inches up the coast from North Carolina to New England. When a hurricane hits land, it quickly loses steam.
High winds are the biggest threat to utility wires and poles. Recent heavy rains in the region have made trees even more vulnerable to toppling over. Flooding can cause problems for power plants, which are often located near rivers or other bodies of water.
The path and strength of the storm is still uncertain. However, utilities are preparing for the possibility that outages will be widespread and lengthy.
"It's going to be really tough," says Karen Johnson, a spokesperson for PSE&G, which serves 2.2 million customers in New Jersey. She recommends customers stock up on supplies of food and water before the storm hits.
"You could conceivably have millions of people without power," said Matt Rogers, President of Commodity Weather Group, which forecasts weather effects on businesses.
Irene could hit North Carolina's Outer Banks on Saturday afternoon with winds around 115 mph, then head up the coast.
The governors of North Carolina, Virginia, Maryland, New Jersey and New York declared emergencies, and authorities all the way to New England urged residents in low-lying areas to gather supplies and learn the way to a safe location.
There isn't much a utility can do to prevent outages. But industry officials say they have learned from past hurricanes how to restore power as quickly as possible.
"Customers will spot us a few days if there's a major hurricane, but once you start getting into day three of not having power it stops becoming an adventure or a minor inconvenience and it starts becoming a real pain," says Scott Sutton, a spokesman for Progress Energy, a utility that serves coastal North Carolina, where the storm is expected to hit first.
For Irene, Progress has assembled teams and equipment that will be sent to regions that are expected to be hardest hit. The company has secured hotel rooms for workers to say, caterers to feed them, and trailers to turn into command centers.
About 1,000 extra workers will be needed to clean up after Irene if it hits as a category three storm, Sutton said.
For power plants, the preparations are different. They are built to withstand hurricane-force winds and beyond, so they are usually not damaged in storms. But they have to be secured, and they may need to be shut down.
Among the most important tasks: everything near the plant that can possibly be picked up by wind and blown into the switchyard or other equipment is secured-even garbage bins are emptied and removed.
At coal plants, coal piles are secured so large amounts of dust and bits of coal aren't blown around. As much coal as possible is brought inside so it doesn't get soaked by the drenching rains.
At nuclear plants, watertight doors are inspected and backup diesel generators are tested. Nuclear plants have different procedures based on their design and location. Typically they must be shut down between two and 24 hours before hurricane force winds are expected or if water levels of nearby water bodies rise beyond a certain level. If hurricane winds are sustained or if water levels rise dangerously, the Nuclear Regulatory Commission is notified of what is called an "unusual event."
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