Most Elbowoods government offices, including the Bureau of Indian Affairs, moved their operations to the rolling, mostly treeless prairie, to the aptly named hamlet of New Town. Dr. Wilson set up shop on Main Street. Today, North Dakota's longest bridge stretches nearly a mile across the white-capped water of Lake Sakakawea toward Four Bears Village and a 17-year-old casino -- one reason reservation unemployment has dropped from an estimated 80 percent after the flood to about 30 percent today. Fort Berthold is on much firmer economic ground than many other High Plains reservations, although not nearly on a par with the rest of North Dakota, which enjoys the country's lowest unemployment rate at 4.2 percent. A rich oilfield was recently discovered under the reservation, and oil rigs now dot the landscape like oversized praying mantises. The boom has generated much-needed revenue for the tribe, supplemented by the casino and a 1993 settlement for dam-caused damages that provides $8 to $9 million annually to community programs. Still, for years people have complained that the federal government never made good on its promise to replace the flooded hospital at Elbowoods. And although the oil boom has brought money, it has also brought an increase in traffic deaths and social tension, along with environmental concerns so profound that some wonder if the reservation will be habitable in 20 years.

But that's getting ahead of the story.

Back in the mid-1950s, after the floodwaters covered his house, Thomas Spotted Wolf sat down on a piece of driftwood log. "He was singing a song, and he had tears coming down," says his grandson, Jim Bear. "I didn't have to ask him what was wrong. ... After that, my grandfather just went downhill. He didn't have anything to live for any more."

Marilyn Hudson's father, who had also poured his life into fighting the dam, died just a month short of his 58th birthday. Other tribal members seemed to wither away as their farms disappeared. "Our neighbor to the north, Judge Wolf, he would hold court right in his house," says Hudson. "He was very adamant -- 'I love this land, I will not leave this land.' And he didn't leave. He died. I'm thinking he wasn't any more than in his 50s."

"The lake forced us into a cash economy," says Leo Cummings, the tribal administrator of employment training. "A lot of people lost their lives in downtown New Town, lost their self-esteem and drank themselves to death." Some found low-paying government or service jobs. Others took the bus to distant cities like Los Angeles or Chicago as part of the Urban Indian Relocation Program.

In the early 1970s, less than 20 years after the creation of the lake, an Indian Health Service doctor named James Brosseau heard reports of diabetes on Fort Berthold and went to take a full inventory. He found 200 cases. "There were probably a lot more that were undiagnosed," he says. When he discovered similar outbreaks on other Northern Plains reservations, it reminded him of the smallpox epidemic that wiped out huge numbers of Indians in the early 1800s. "Diabetes is going to devastate the tribes," he recalls thinking. "It's going to be a long, painful death, not a quick one." He adds, "I'm even more concerned now. It hasn't improved. Rates have gotten worse."

To address the problem, Congress established the Indian Health Service Division of Diabetes in 1979. "By the late 1980s and 1990s, diabetes was a well-known epidemic among American Indians," says Charlene Avery, director of the IHS Office of Clinical and Preventive Services.

Virtually all of the people using tribal health facilities on Fort Berthold are Native American. They're either among the reservation's 4,556 Native residents or they live off the reservation and drive in for medical care. In 2008, the 18-74 year olds in this group had an obesity rate of just over 60 percent. In 2009, more than 13 percent of the people using the health system had diabetes, making it the single biggest diagnosis for the group and roughly twice the state average of 6.5 percent. Diabetes risk increases with age, and among people over 35, about 41 percent appear to be diabetic.

Almost all of the diabetes cases on Fort Berthold and beyond are Type 2, which usually develops in overweight adults who become resistant to their own insulin. Type 1 diabetes -- an autoimmune disease that typically begins in childhood and causes the body to produce insufficient insulin -- has stayed stable at about 5 percent nationwide, according to Brosseau. Insulin moves glucose, the body's basic fuel, from the bloodstream into cells so it can be used for energy. When sugar can't move into cells, it builds up in the blood, causing symptoms like weakness, impaired circulation and thirstiness. Its complications can include loss of vision or limbs, heart disease, diabetic coma, and kidney failure, which can be treated with dialysis.

Type 2 diabetes can be prevented or managed with regular activity and a low-fat diet with plenty of fruits and vegetables. "People don't get as much exercise as they used to," says Jared Eagle, 28, who grew up with a diabetic grandmother, grandfather and uncle and is the fitness director for the Fort Berthold diabetes program. "They don't ride bikes. Video games are huge. They do them at home, and there's an arcade at the casino. Kids get rides just down the block. Things like that really show."

Dialysis patients -- 95 percent of whom have diabetes -- have tripled in the last eight years, according to Stella Bergquist, an RN on Fort Berthold. Fourteen people are on the waiting list for the life-saving treatment. "We have 10 dialysis patients at a time, two shifts a day," says Bergquist. The tribe transports the extra patients off the reservation to Minot, 70 miles away, and beyond.