Tens of thousands of lineworkers and tree trimmers were hard at work from Florida to South Carolina to restore power to more than a million customers left in the dark by Hurricane Michael.

The most powerful hurricane to make landfall in the Florida panhandle in at least 150 years smashed houses, sent a storm surge dozens of miles inland, tore up thousands of trees and cut power to an estimated 1.3 million customers. At least 11 people have been confirmed dead.

Hurricane Michael was the third most powerful hurricane to hit the continental U.S. and the strongest since Hurricane Camille in 1969. Sustained winds in excess of 150 mph and a storm surge that exceeded 7 feet did billions of dollars of damage.

From all across the state and country, thousands of IBEW line workers staged safely outside the heart of the storm, waiting to enter what Florida Power and Light System Council 19 Business Manager Gary Aleknavich called “the devastation.”

The Edison Electrical Institute said that more than 30,000 lineworkers and tree trimmers were sent to Alabama, Florida, Georgia and the Carolinas from 24 states. The Florida Division of Emergency Management said 19,000 power restoration personnel were pre-positioned there prior to the storm.

Hurricane Michael made landfall as a near-category 5 storm with sustained 155 mph winds, stronger than Katrina or Andrew, and far stronger than Florence which caused more than $45 billion in damage just last month. Only the so-called Labor Day hurricane of 1935 and Camille in 1969 registered a lower barometric pressure as they came ashore, the most accurate way to determine the total power of a storm.

Hurricanes get their power from warm water and tend to weaken when they hit land, but the National Weather Service said this was not the case with Michael and issued an extraordinary extreme wind warning, which was, in effect a three-hour long tornado warning. The announcement included this all-caps warning: “THIS IS AN EXTREMELY DANGEROUS AND LIFE-THREATENING SITUATION.”

As meteorologist Matthew Cappucci put it, “Imagine a tornado parking over you for three hours. This is it.”

The storm arrived at the highest tides of the year, the King Tides, when the moon is full or new and the earth is closest to the sun. It was, said NWS Director Louis Uccellini, the “worst case scenario.”

As the sun rose Thursday morning, the toll was clear. The Department of Energy reported 310,000 outages in Florida, 336,000 in Georgia, 101,000 in South Carolina, 61,000 in Alabama and more than 13,000 in North Carolina.

Gulf Power’s territory bore the brunt of the storm and company spokespeople said in some areas recovery will require rebuilding the system, not merely repairing it.

Of the 103,000 customers in Bay County, where the eye of the hurricane came ashore, 24 hours later nearly all of them were without power. To the north, no one had power in Holmes county and fewer than 300 of Gulf Power’s customers had power in Washington County. 

In the first 24-hours, the company reported it had 4,000 crew members at work, including 2,600 from at least 15 different states, ranging as far north as Michigan and as far west as Oklahoma and Texas.

They successfully restored power to 25,000 customers out of nearly 120,000 total outages, a figure significantly better than the 225,000 that had been predicted.

Duke Energy Florida’s territory lies just east of Michael’s landfall. Before the storm, the company warned that up to 200,000 customers were at risk of losing power. But after the wind and rain subsided, the company reported only 30,000 customers without power. Line workers from Duke Energy’s Indiana, Ohio and Kentucky were brought in, and the company made mutual assistance requests to utilities in Mississippi, Alabama, Louisiana, Illinois, Texas and Missouri.

The situation was much worse in the Carolinas, where Duke is the dominant utility. More than 500,000 customers lost power in Duke Energy Carolinas’ territory, where more than 400,000 were still without power Friday afternoon. The company said it had nearly 7,000 workers already there.

Nearly 4,000 workers were in place for Georgia Power –the largest subsidiary of Southern Co. covering nearly the entire state. By Thursday afternoon, the company reported 123,472 affected customers, down from the peak of 200,000.

The mutual assistance program is managed by the EEI through seven regional assistance groups. When an EEI member thinks it needs help, it sends a request to the Regional Mutual Assistance Group which identifies available workers and helps coordinate everything from lineworkers, tree trimmers and equipment to call center support.

The largest mutual assistance response was in 2012 after Superstorm Sandy knocked out power for over 10 million customers in 24 states in the Northeast, Mid-Atlantic and Midwest.

More than 50,000 workers from almost every state and Canada were called in to repair the damage.

When it was originally designed, the RMAG system was designed primarily as a response to regional events. In recent years as storms have grown in frequency and intensity, EEI developed the National Response Event program to scale the regional response.

While the goal of power restoration is to get the power back on as quickly as possible, the first step utilities take when a natural disaster hits is often the opposite. Typically, companies’ first step is to make sure lines are deenergized, to prevent electrocution of people in standing water and to prevent home or wild fires. Only after public safety is assured, crews begin their work based on pre-established priorities.

First come power plants and transmission lines. Then crews restore substations and service to emergency responders including hospitals and water treatment plants. Only then do significant  resources turn to restoring the bulk of the distribution systems, focusing on population centers first and moving finally to isolated single-family homes.

Easier said than done in a disaster this widespread said Utility Department Director Donnie Colston.

“We have the men and women to clear the trees, set new poles and hang new lines, but it isn’t always up to us,” he said. “Whole circuits are down and hundreds of poles. And the infrastructure has to be replaced. I’ve seen videos with half a mile of road just washed away