SANTO ANTONIO, Brazil —

The wind blows in from the river, mingling with the scent of the day’s last meal in the kitchen. The smells of work and home for Valcione da Silva. He sits on a worn bench and watches children play on the floor, laughing. Somewhere outside, a siren begins, long and loud.

Da Silva reaches beneath his bench to retrieve two knives, double-edged like daggers. They’re not weapons, he says, clattering them together. They’re special fishing tools. “Only wood,” he says. He ignores the siren.

He pulls out what appears to be a string of plastic Coke bottles dangling from a belt. “Look,” he says, pressing into the side of a bottle. It flexes open along a slit in the plastic. When he lets go, it springs closed again. “Very simple. I can keep them alive in here.” His fish are delicate, he says.

A moment later a boom shakes the little home, and a concussion rolls the air like a wave on the river. Dirt dances on the floor. The nearly bare shelves rattle. Another boom, and outside in the yard, the leaves of da Silva’s mango tree flicker green and silver.

Da Silva walks to his doorway with his wooden daggers, and looks like a man standing at the edge of the world.

During the past year, the villagers around him have packed up and left. A few days ago the school closed, because all but da Silva’s children had left. His wife was the teacher, so she continues their lessons at home. Santo Antonio would look like a ghost town, except that bulldozers have leveled all the empty homes.

Da Silva watches the trucks as they rumble past, carrying countless tons of earth, blown with dynamite from the hillsides where he was born. “I want to stay and fish,” the 36-year-old says. But it’s early December, and he’ll have to leave soon; clever men with clipboards have outmaneuvered him.

In the morning, he says, he will do the only thing within his power. He’ll break the law.

Resisting progress

Progress and the past are colliding at da Silva’s doorway.

His small home sits at the foot of the Belo Monte dam site, where a consortium is building the third-largest dam in the world, almost four miles across the Xingu River, a $16 billion construction project in the heart of the Amazon basin.

Indigenous tribes and environmental groups have cried out against the dam for reasons local and global; the tribes depend on the mighty Xingu River — one of the Amazon’s largest tributaries — for transportation, and their livelihoods. Environmental groups say the dam will destroy rain forest that the world needs to breathe. The builders counter that millions of Brazilians need the electricity, and construction continues.

There had always been talk of a gigantic dam. During the dictatorships of the 1970s, important men had made speeches about the riches of the Amazon, waiting to be discovered.

In 1972, President Emilio Medici had shown up with a construction crew just outside Santo Antonio. The president cut down a Brazil nut tree — a symbol of the rain forest — and stood on its fresh stump to make a speech about bringing industry, roads and population to the Amazon. Part of the plan, starting in 1975, was to build a massive hydroelectric dam.

There’s a pattern, in Brazilian history, of industries focusing on one natural resource, stripping it, and moving on to another. When Portuguese colonials arrived, the Brazil nut tree was so plentiful the explorers named the country after it. Now the trees are endangered. Later prospectors found so much gold they named an entire state Minas Generais, or General Mines. The gold is dwindling too. The same happened with the rubber trees, and the diamonds.

The Amazon’s river system, though, seemed to resist progress for many years. The first bridge in the entire Amazon basin wasn’t built until 2010. The area was too difficult to reach. Too wild a riverbed. Populated by too wild a people.

The dictator’s workers symbolically paved the top of the stump where Medici stood to make his speech, and today it stands shrunken and cracked. Now an enormous concrete power pole looms over the stump. It’s one of an endless series of identical towers, marching electricity to the reawakened site of the dam called Belo Monte: the Beautiful Mountain.

Who gets the power?

Men came to Da Silva’s door a couple of years ago and knocked.

We are subcontractors to Norte Energia, the head man told him. We are building the dam.

They entered his home with a clipboard, writing a list of all his meager possessions. He followed them from one small room to another, as questions tumbled through his mind: What on earth is Norte Energia? And why do these men have a clipboard?

Life in Santo Antonio had stayed quiet for the past three decades, but elsewhere in Brazil a revolution had been under way: an industrial, financial and cultural revolution. The country had recently surpassed Britain to become the sixth-largest economy in the world. And the Brazilian machine needs electricity.

“Electricity is development,” said Joao Pimentel, director of institutional relations for Norte Energia, a consortium of private and state-held companies that plans to begin operating Belo Monte in 2015. “Without electricity we will go nowhere.”

“If all the electricity went to homes, the dam would provide power for 60 million people, Pimentel said.

It won’t do that, exactly. Seventy percent of the dam’s power will flow to public utilities, sold on the national grid for business and domestic consumption. The other 30 percent will be divided between shareholders. So how many Brazilian citizens will receive electricity once it trickles down? “It’s difficult to say,” Pimentel said.

“That’s a lie,” said professor Rodolfo Salm, who researches ecology at the federal university in Altamira, the largest town near the dam site. “This energy is not for homes, it is for mining.”

As Brazil expands its economic reach in the world, Salm said, it exports more goods. Aluminum, for instance. “It takes a lot of energy to produce aluminum,” he said. “In Japan, they need aluminum but have an energy shortage. So what we are really doing is exporting energy.”

A furtive fishing trip

Da Silva’s brother-in-law, Alessandro da Silva, joins him, and they sling their equipment in packs over their shoulders.

They climb onto da Silva’s off-road motorcycle. He fires it up, and the two scoot into the rumble of transfer trucks. Dust coats the men, and the tires of the other vehicles tower above them.

Gigantic machines scrape and gouge and dynamite rock and dirt and load it into the trucks, which haul it to other sites, where they unload and repeat. Da Silva and Alessandro weave through a landscape that stopped resembling the rain forest long ago; now it looks lunar.

Off a side road they pass the village’s empty church, and the demolished houses of their former neighbors. As they get closer to the Xingu River the signs start appearing: Do not enter, they say. This land is now protected by the law. Do not enter.

The two men drop on their motorbike over the riverbank, out of sight. Working quickly, they slide down the bank to their dugout canoe, crank its small motor and then navigate into the Xingu.

The Xingu is special, among all rivers in the Amazon system. Where the Amazon descends just 80 meters over its length of almost 4,000 miles, the Xingu drops 90 meters over a 60-mile segment here.

And it is special for another reason, da Silva says.

“Getting close now,” he says.

He putters past another sign, this one bobbing in the water: Do not enter.

Dam will be built in stages

The Belo Monte project itself was deemed illegal, briefly, by the Brazilian federal court. In mid-August, the court intervened to halt all construction.

Two weeks later, the Supreme Court reversed the decision. Civil rights and environmental groups cried out against the decision, claiming the courts had bowed to pressure from Brazilian President Dilma Rousseff, whose 2011 election was underwritten in part by the companies interested in building the dam.

The dam is a complex, multi-stage affair, but it will work like this: The Xingu flows downhill from Altamira to Santo Antonio — Valcione da Silva’s village — where the water will crank the dam’s turbines. Between those two points, though, the river swings through what locals call the Big Bend. It’s a wide loop where botanists, zoologists and anthropologists study life of all sorts; it’s also flat, so the river loses much of its valuable energy. So a support dam will shunt most of the Xingu directly from Altamira to the dam, through a man-made canal. It will cut out the Big Bend — and slowly lower the river there.

Beneath the surface

Valcione da Silva steers his dugout boat around a final bend.

He will take the settlement, he says. He has no choice. Norte Energia alone cannot cast him from his home, but the government can. He will have to take the money — about $20,000, he says — and move from his home. But he will hold out as long as possible.

He stops the boat at the center of the river, and Alessandro throws out the anchor. At the center of the boat, da Silva takes the cover off a funny old engine, which looks like something salvaged from a steam ship. It’s bright yellow, all gears and wheels and chains. It sputters to life.

“Air compressor,” Da Silva says. Two plastic tubes run from the engine, and the two men each place the free ends in their mouths. They pull on goggles, strap the Coke bottles around their waists, and tuck the wooden daggers into their belts.

They leap.

Slowly he finds them — the beautiful fish. Ornate, tiny fish. Rare fish. At the market in Altamira he can sell them for $2 or $3, although they will sell for a hundred times that much eventually. He doesn’t know the scientific names, or the ones they’ll have by the time they reach aquariums in Tokyo or New York. But here they’re called the zebra, the old black man, the tiger.

They resist, hiding under the river rocks. But his daggers eventually, inevitably, sweep them from their homes.