HADENYA, Japan » The colossal wave that swept away this tiny fishing hamlet also washed out nearby bridges, phone lines and cellphone service, leaving survivors shivering and dazed and completely cut off at a hilltop community center.

With no time to mourn for their missing loved ones, they were immediately thrust into the struggle to stay alive in the frigid winter cold, amid a hushed, apocalyptic landscape of wrecked homes, crushed vehicles and stranded boats. They had scant food and fuel and no news from the outside world — not even the scope of the devastation.

On Wednesday, after the Japanese military finally reached them for the first time since the tsunami struck 12 days ago, by erecting makeshift bridges and cutting roads through the debris, they told a remarkable tale of survival that drew uniquely on the tight bonds of their once-tidy village, having quickly reorganized themselves roughly along the lines of their original community: choosing leaders, assigning tasks and helping the young and the weak.

The ability of the people of Hadenya to survive by banding together in a way so exemplary of Japan’s communal spirit and organizing abilities is a story being repeated day to day across the ravaged northern coastline, where the deadly earthquake and tsunami left survivors fending for themselves in isolated pockets. Some are still awaiting relief.

Almost as soon as the waters receded, those rescued here said, they began dividing tasks along gender lines, with women boiling water and preparing food, while men went scavenging for firewood and gasoline. Within days, they said, they had re-established a complex community, with a hierarchy and division of labor, in which members were assigned daily tasks.

They had even created a committee that served as an impromptu governing body for this and five other nearby refugee centers, until the real government could return.

“We knew help would come eventually,” said Osamu Abe, 43, one of the leaders who emerged to organize the 270 survivors. “Until then, we had to rely on each other to survive.”

Refugee centers like this one in Hadenya exhibit a proud cooperative spirit, and also a keen desire to maintain Japan’s tidy perfectionism. Along the hallways, boxes of supplies lie stacked in orderly rows. The toilets are immaculate, with cups and soap neatly lined up. At the entrance, sheets of paper list names and assigned tasks for the day, such as chopping firewood, carrying supplies and cooking.

Many of those here say that local villages like this one had to be self-reliant because of geography: they lie in remote inlets along a mountainous coastline.

“We have shown that we can take care of ourselves by ourselves,” said Hideko Miura, 50. She said she survived the tsunami by climbing up a hillside, and then screamed as she watched the wave drag her home out to sea.

Residents credited the close proximity of high hills, and years of annual tsunami drills, with keeping the number of missing and presumed dead down to about two dozen.

Abe said he naturally assumed a leadership role over the frightened survivors because had a prominent job in the village, as head of the local nature center. He said the first thing he did after the tsunami was get the older schoolchildren to erect tents in the community center’s parking lot, since aftershocks made survivors afraid to sleep inside.

Later, he sent a group of survivors down to a local marsh to get water, and others to gather firewood — mostly the wooden debris from broken houses — in order to boil it. When one survivor turned out to be a nurse, he asked her to set up a makeshift clinic, behind a sheet in one corner of the center, which was now filled with survivors sleeping on the floor.

“People needed a sense of direction,” Abe said. “They were stunned from having lost everything.”

The next day, groups were sent to scour the wreckage for supplies. One found a truck washed up by the waves that was filled with food, which barely kept them fed until the first helicopters reached them four days later.

Another group searched for fuel. Shohei Miura, a 17-year-old high school junior, said he helped drain gasoline from the tanks of the dozens of smashed cars left behind by the tsunami. He also found kerosene in beached fishing boats.

“I never imagined we would get so desperate, but everybody had to do such jobs in order to survive,” Miura said. He said he survived the tsunami itself by climbing to his roof, and then leaping from rooftop to rooftop of floating homes before swimming through the wave’s currents to a hillside.

Abe said most survivors from Hadenya found it easy to cooperate because they had organized themselves to hold the village’s religious festivals. He said a small number declined to cooperate, but he overcame this by offering them positions of responsibility, which had the effect of motivating them.

Although they were cut off from the rest of Japan, they made contact with five other nearby refugee centers, with another 700 survivors. Representatives from the centers met daily to swap supplies and assign tasks. Abe’s center was designated as the clinic and helipad, because it had a sports field.

It was not until the first helicopter arrived that the isolated group learned from a newspaper onboard of the extent of the devastation across northern Japan.

“We spent days wondering whether it was just us who got hit, or other parts of Japan, too,” said Sachiko Miura, 59, an employee in the village’s fishing co-op who now serves as the refugee center’s quartermaster. “We never imagined it was this bad.”

The helicopters finally came because the group assigned messengers to make the arduous hike across mountainsides to reach the main town of Minamisanriku, of which Hadenya is a part. Kazuma Goto, 63, a farmer, was one of three who made the five-hour journey, carrying a list of survivors at the six refugee centers.

“Until I arrived, the town thought we were lost,” Goto said.

Almost half of Minamisanriku’s 17,000 residents remain missing. Officials admit that chances of survival are slim. As of Wednesday, the town’s 9,369 survivors lived in 45 refugee shelters like the one in Hadenya.

The mayor, Jin Sato, said that most shelters had spontaneously organized in much the same way as Hadenya’s had. Now, as the town government began to plan for the eventual relocation of evacuees from the shelters into temporary housing, possibly to locations miles away, he said officials were beginning to realize that these spontaneous groupings might have a use.

He said the town had originally planned to put people into housing as quickly as possible. Now, he thought it best to keep these organizations intact, to help people adapt to new and different living environments.

“They are like extended families,” Sato said. “They provide support and comfort.”