More than 1,000 line repair and tree crews fanned across Maine on Tuesday morning with plans to work around the clock to restore power knocked out by Monday’s powerful storm, which caused a record number of outages and heavy damage.

But some of the state’s almost 400,000 customers who awoke Tuesday without power might have to wait until Saturday before regaining electricity, Central Maine Power’s president warned. By 4 p.m. Tuesday, the number of outages in CMP’s service area had decreased to about 285,000.

“We expect to have the vast majority of our customers back on by Saturday night,” CMP President and CEO Sara Burns said Tuesday during a news conference organized by the Maine Emergency Management Agency.

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Alan Richardson, president of Emera Maine, the utility that provides electricity in most of northern Maine, said about 90,000 customers — more than half the company’s 160,000 — were without power Monday, but some 30,000 are already back online. He hoped 90 percent would be back up by Thursday, and the last by Friday.

“We’ve repaired all our transmission systems and most of our substations are up, and we’re working on the distribution system now,” said Judy Long, a spokeswoman for Emera. “So there may be fluctuations in service. We’re working right now to give estimated times of restoration by region.”

Burns said an additional 600 line crews were headed to Maine on Tuesday, along with another 300 tree crews and assessors. They will join the 200 CMP repair teams and 100 tree crews that have been dealing with storm damage since early Monday.

“We will work around the clock,” she said.

Burns said CMP will start estimating restoration times as soon as possible. That had not happened by 4 p.m. Tuesday.

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The damage caused by the storm’s heavy wind and rain is being considered more destructive than the ice storm that froze Maine in its tracks in 1998.

“Folks, this storm was massive,” said Peter J. Rogers, acting director of MEMA. “It caused a larger number of power outages across the state than the ice storm of ’98. But this response has been much better, and it’s working very well.”

However, Rogers said recovery “will be a long-term event.”

Gov. Paul LePage declared a state of emergency on Monday afternoon, making it possible for crews to work longer to repair Maine’s power grid.

In the immediate aftermath of the storm, crews focused on deactivating downed lines to reduce public safety risks. That limited their ability to restore power to customers. On Tuesday morning, nearly half of Maine’s electricity customers remained without power.

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Crews on Tuesday expected to “restore service to large customer groups by completing repairs to transmission and major distribution lines,” CMP spokeswoman Gail Rice said Tuesday morning. Hospitals and care centers also were a priority, she said.

At the Togus VA Medical Center in Augusta, emergency crews delivered a backup generator as a precaution around 3 p.m. Monday, after one of the facility’s own generators started malfunctioning, according to center director Ryan Lilly.

Before the backup arrived, the malfunctioning generator had been replaced by three mobile generators already on site. Normal power was restored by 3:15 and the emergency generator was never used. Patient care was not disrupted by the malfunction, Lilly said.

A representative of Eastern Maine Medical Center said Tuesday that a number of its practices in Bangor and Brewer remained without power, including EMMC Northeast Cardiology, EMMC Children’s Health, EMMC Family Medicine Brewer, EMMC Family Medicine Hampden, EMMC Neurology Specialty Care and the EMMC Sleep Diagnostics Center. Most phone lines are down at these practices, and patients should call the main number at the hospital if trying to reach these practices.

Central Maine Power said downed trees and flooded roads made it difficult to get to areas that needed repair, adding that the damage from the storm is unprecedented.

“This storm left us with the largest number of outages in the company’s history, even higher than the 1998 ice storms that many of us remember,” Rice said.

BDN writers Meg Haskell and Lori Valigra contributed to this report.

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