DEADHORSE -- Unprecedented flooding continues to interfere with daily operations on the North Slope oil patch after surging waters wiped away swaths of the Dalton Highway and isolated a section of Deadhorse, the jumping-off point for the sprawling industrial region.

"This is just epic," said Mike Coffey, commander of the unified incident command, a response team consisting of the state, the North Slope Borough and oil companies. "People who have been here for decades say they've never seen anything like it."

The state has estimated the costs of the damage and repairs since March at $5.1 million. The federal government may pay for much of that, since the icing and flooding on the highway has been declared a disaster, said Coffey, the director of state transportation maintenance and operations.

The event was caused by heavy summer rains followed by extensive freezing this winter, trapping the water in place, then a rapid spring warmup that has brought record temperatures to the region.

"It's kind of a perfect storm for things to go south," said Coffey.

Viewed from the air for some 20 miles south of Deadhorse, the highway and elevated trans-Alaska pipeline appear like spines above a sea of water, with the Sagavanirktok River tumbling in white currents across sections of the highway. One section of severed road appears to stretch a half-mile long.

It's impossible to know the real cost of the damage since many sections of the gravel road are still swamped with water. It's also impossible to know how long until the highway is opened, said Coffey.

"The best guesstimate is the high water is expected to last another four days," he said. Officials hope repairs can begin immediately after that.

The trans-Alaska pipeline -- and the oil flowing through it that produces the bulk of state revenues -- isn't threatened, said Michelle Egan of Alyeska Pipeline Service Co.

The flooding has been expected since March and April, when portions of the Dalton became an icy luge course with meltwater on top of it, forcing the state to temporarily close the sole road to the North Slope.

At the time, hundreds of supply truckloads were put on hold and fuel tanks had to be flown in and hauled across the frozen tundra on "rollagons" -- big-wheeled freight trucks. Gas prices skyrocketed, doubling to almost $10 a gallon.

After that closure, North Slope operators and contractors bulked up on supplies, expecting more flooding with the spring melt. They got it after the river, which empties into the Arctic Ocean on the east side of the highway, began pouring across it, with two major breaches at about 15 and 20 miles south of Deadhorse.

Earlier this week, the floodwaters threatened the airport, forcing the state to excavate large chunks from the road that were already eroding in order to create an outlet.

The waters trapped three of Deadhorse's numerous camps -- elevated gravel pads supporting buildings and equipment.

At Deadhorse Camp, the flooding damaged building materials needed for an interior renovation. In response, Wayne Merriman of Merriman Construction in Fairbanks ordered an emergency shipment of acoustic ceiling tiles and other supplies to be flown in.

To get the supplies from the airport, he boarded a small skiff that hadn't been used by the camp in years after finding an ill-fitting engine and cobbling together parts to get it running.

On Thursday, he motored slowly across the newly formed lake around Deadhorse Camp to pick up the shipped supplies, pushing with poles when the propeller hit tundra.

"We're going to finish this project on time and on budget," he said.

The area with the three flood-locked camps also lost power and Deadhorse Camp was relying on generators for electricity. A telecommunications line carrying local Internet and phone service was also damaged and could be seen fluttering in the rapids along a large severed section of highway.

"I was thinking, 'What is this?'" said John Bollinger, who works at Deadhorse Camp. "Then I go to use the Internet. 'Oh, that's what that was.'"

The closure forced Brice Equipment to temporarily send a few workers home. Several pieces of heavy equipment rented out by the company were cut off by the high water, said Andre Vachon, Deadhorse manager for the company.

The floods also affected efforts at a soon-to-be-built $30 million camp for ASRC Energy Services that will serve primarily as a vehicle maintenance facility.

Builders were forced to fly in insulation panels, adding $140,000 to the costs, to keep the project on schedule, said Doug Smith, president and CEO of Little Red Services.

Smith attended a ground blessing for the facility Thursday. On the way in, he said he flew over the flooding and couldn't believe its breadth.

"It's substantially worse than I thought," he said. "It'll be a while before the experts can figure this one out."

Some oil field roads have also been swamped with water and oil companies are working to protect those, said Coffey.

The good news on Thursday afternoon was that some of the flooding had receded.

And steps taken by the transportation department in March and April -- when river channels remained frozen solidly to the ground, plugging up the usual outlets to the Arctic Ocean – have helped, said Coffey.

The efforts then included creating long diversion channels through the frozen Sag River.

The department also hired a crop duster from Fairbanks to scatter sand across the eastern channel of the Sag River. The dark sand on the white ice helped accelerate melting, forcing the flood waters toward that channel and farther away from the road.